• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3C
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• pp.115-125
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• 2009

The preconsolidation pressure has been commonly determined by oedometer test. However, it can also be determined by insitu test, such as piezocone test with theoretical and(or) empirical correlations. Recently, Neural Network (NN) theory was applied and some models were proposed to estimate the preconsolidation pressure or OCR. It was already found that NN model can come over the site dependency and prediction accuracy is greatly improved when compared with present theoretical and empirical models. However, since the optimization process of synaptic weights of NN model is dependent on the initial synaptic weights, NN models which are trained with different initial weights can't avoid the variability on prediction result for new database even though they have same structure and use same transfer function. In this study, Committee Neural Network (CNN) model is proposed to improve the initial weight dependency of multi-layered neural network model on the prediction of preconsolidation pressure of soft clay from piezocone test result. Prediction results of CNN model are compared with those of conventional empirical and theoretical models and multi-layered neural network model, which has the optimized structure. It was found that even though the NN model has the optimized structure for given training data set, it still has the initial weight dependency, while the proposed CNN model can improve the initial weight dependency of the NN model and provide a consistent and precise inference result than existing NN models.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.294-300
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• 1999

After researching the physical properties of the concrete included Rice Husk Ash(RHA concrete) and workability of fresh concrete admixed RHA, we have tested durability of RHA-concrete against freeaing and thawing in the winter using rapid freezing and thawing test method(KS F 2456) . There aretwo hypotheses to explain the failure mechanism of a freezing and thawing action. First, the hydraulic pressure in the pores of freezing concrete make an internal stress of concrete structures outbreaking micro crack in the face of concrete, Second, Frost action causing damage to cement paste repeatedly come from soil frost action, freezing water in the capillaries. Initial Relative Dynamic Modulus of Elasticity (DME) was biggest in cae of unit binder weight 600kgf/㎥ and relative dynamic modulus of elasticity increased until 300cycles. In general , initial relative DME was proportional to unit binder weight . Relative DME was decreased in proportion to unit binder weight in the case of 300, 400, 500kgf/㎥ , but relative DME fo the others remained more than 90% until 300 cycles. It was not good effect of intermixed RHA to concrete in case of below unit binder weight 300kgf/㎥ and the resistance of freezing and thawing was not good either.

• Development and Reproduction
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• v.19 no.1
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• pp.43-51
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• 2015

Connexin (Cx) is a complex which allows direct communication between neighboring cells via exchange of signaling molecules and eventually leads to functional harmony of cells in a tissue. The initial segment (IS) is an excurrent duct of male reproductive tract and expression of numerous genes in the IS are controlled by androgens and estrogens. The effects of these steroid hormones on gene expression in the IS during postnatal development have not extensively examined. The present research investigated expressional modulation of Cx isoforms in the IS by exogenous exposure to estrogen agonist, estradiol benzoate (EB), or androgen antagonist, flutamide (Flu), at weaning age. Two different doses of EB or Flu were subcutaneously administrated in 21-day old of male rats, and expressional changes of Cx isoforms in the adult IS were analyzed by quantitative real-time PCR. Treatment of a low-dose EB ($0.015{\mu}g/kg$ body weight) resulted in an increased expression of Cx31 gene and a decreased expression of Cx37 gene. A high-dose EB ($1.5{\mu}g/kg$ body weight) treatment caused an increase of Cx31 gene expression. Increased levels of Cx30.3 and Cx40 transcripts were observed with a low-dose Flu ($500{\mu}g/kg$ body weight) treatment. Treatment of high-dose Flu (50 mg/kg body weight) led to expressional increases of Cx30.3, 40, and 43 genes. Our previous and present findings suggest differential responsiveness on gene expression of Cx isoforms in the IS by androgens and estrogens at different postnatal ages.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.610-617
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• 2000

The indigestible dextrin with high indigestible fraction was prepared by treating the enzyme hydrolysate of pyrodextrin with ethanol or strongly acidic cation exchange resin(UBK 530). Optimum conditions of ethanol treatment for preparing the indigestible dextrin from $\alpha-amylase$ and amyloglucosidase treated hydrolysate were determined based on the indigestible fraction, dietary fiber content, and yield. Ethanol was added 5-fold by weight to 30%(w/w) enzyme hydrolysate, and the mixture was kept at room temperature for 3 hr. Low molecular weight saccharides containing glucose and high molecular weight saccharides were separated by strongly acidic cation exchange resin. While initial enzyme hydrolysate by $\alpha-amylase$ and amyloglucosidase showed 43.6% of DPI(glucose) and 51.1% of DP4+(maltotetraose and over), the indigestible dextrin collected to 50% of initial enzyme hydrolysate by treatment of cation exchange resin showed 7.1% of DPI(glucose) and 91.2% of DP4+(maltotetraose and over). In conclusion, 44.5% of indigestible fraction of initial enzyme hydrolysate increased to 78.9% after separation of low molecular weight saccharides.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.6
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• pp.462-470
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• 2016

The locking load of a conventional manhole depends on the weight of its cover. Locking-type manhole structures with a special locking mechanism were recently developed to prevent accidents such as stolen cover, away cover from a frame. The weight of the manhole structure can be reduced under structural safety because the locking force of a locking-type manhole is greater than the weight of the cover. A light-weight manhole cover is developed in this study by using a finite element stress analysis and the design of experiments. Static stress analysis and fracture experiments are also conducted to analyze the states of the initial product. The optimum light-weight manhole cover considering manufacturing molds is developed and tested. Consequently, the weight was found to reduce by 16%. In addition, the fracture load increased by 38%.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.5
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• pp.527-534
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• 1997

Freezing of an aqueous sodium cWoride solution (Nacl- H20) saturating a packed bed with ini¬tial salt concentrations of 5, 10, 15(k by weight is investigated experimentally in a rectangular cav¬ity. The system was cooled from the top, bottom and a vertical side wall. For the freezing experi¬ments from below, there was little effect of the initial salt concentration throughout the freezing process, and the global freezing rate was not affected by the initial salt concentration. For the freezing from above, the size of the mush region decreased and the mushlliquid interface became flatter as the initial liquid concentration is decreased. For the freezing from vertical side wall, reheating of the mixture was intensified with an increase in the initial salt concentration. For Ci= 5%, supercooling was observed only at the early times of freezing process, but for Ci= 15% small supercooling was observed throughout the freezing process.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.04a
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• pp.287-294
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• 1999

The tensegrity structure by prestressed cable, which may have large freedom in scale and form and therefore are received much attention from the view points of their light weight and aesthetics, is a very flexible and geometrically unstable structure because the cable material has little initial rigidity. For the stable self-equilibrated state of the usually very deformable structure, the method to find the optimal initial stress by the shape analysis is proposed in this paper. The proposed procedure is to derive the nonlinear finite element formula of cable and truss members considering geometric nonlinearity and used to modified load incremental method adding to Newton-Raphson method with the proposed condition for optimal initial stress. The result of the shape analysis for the tensegrity structure with the radius of 30m is shown the almost approximated shape to architectural shape and the changed procedure of initial stress

• Archives of Obesity and Metabolism
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• v.2 no.1
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• pp.6-10
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• 2023

Compensatory changes in energy consumption and neuro-hormonal changes following weight loss make it difficult to maintain the reduced weight and may cause weight regain. Therefore, establishing a long-term weight control plan and strategy starting from the initial weight loss period is necessary. Both the patient and doctor should know that weight loss cannot occur continuously, and that maintaining weight after the weight loss period is the basic course of obesity treatment. No single dietary pattern is effective for weight maintenance, and a variety of dietary control methods - such as calorie restriction and healthy proportions of carbohydrates, proteins, fats, and meal replacements - should be used to target an integrated and healthy dietary habit. An increase in physical activity is needed for weight loss and maintenance; however, rather than recommending an excessive amount of exercise, it is better to set realistic and long-term achievable goals. It is necessary to reset the goal according to the patient's weight maintenance stage and continuously apply behavioral therapies, such as self-monitoring and stress management. In previous studies, since the degree of weight loss and changes in behavioral patterns over the course of one year were important factors in maintaining long-term weight loss, obesity therapists should closely examine patient data and behavioral patterns across a period of one year and actively intervene when needed.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.774-780
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• 2000

For this study three types of block such as medicated urea-molasses-mineral block (MUMMB, 7% urea), urea-molasses-mineral blocks ($UMMB_a$ 7% urea) and urea-molasses-mineral blocks ($UMMB_b$ 21% urea) were prepared. Naturally infested 24 indigenous dairy cows with gastrointestinal nematodes were used to study the effect of MUMMB, $UMMB_a$ and $UMMB_b$ on different parameters (body weight, milk yield, serum urea level, milk urea level). The cows were offered normal diet added with 250 g block per cow for every day. Straw and green grasses were used as basal diet in the ration. The managemental facilities for all cows of each group were similar. Cows were stall fed, calves were tied up at night and had free access to their dam during day time. Milking was done once daily in the morning. The daily average live weight gains by MUMMB, $UMMB_a$, $UMMB_b$, and control group (no block) were 52.08 g, 44.44 g, 48.58 g, and 1.41 g respectively. The live weight gain were statistically significant (p<0.01) in comparison to control group. The highest daily milk yield was observed in MUMMB treated cows (2.39 L/d); followed by $UMMB_b$ treated cows (1.82 L/d) and $UMMB_a$ treated cows (2.16 L/d). The lowest milk yield was found in control group (1.54 L/d). This result differs significantly (p<0.05) between treated groups and also with control group. During urea-molasses-mineral blocks $UMMB_a$, $UMMB_b$ licking milk urea level increased from initial $22.76{\pm}2.35mg/dl$ to $35.46{\pm}4.80mg/dl$ and initial $22.86{\pm}2.96mg/dl$ to $40.66{\pm}0.87mg/dl$ respectively. This variation of milk urea level was statistically significant (p<0.001). Similarly during $UMMB_a$, and $UMMB_b$ blocks licking, serum urea level increased in both treated groups from initial $22.76{\pm}2.60mg/dl$ to $32.68{\pm}2.21$ and initial $23.70{\pm}2.78mg/dl$ to $40.48{\pm}3.24mg/dl$, respectively. This variation of serum urea level was also statistically significant (p<0.001). Use of MUMMB instead of UMMB was proved better for milk production and live weight gain in dairy cows under the village condition of Bangladesh where balanced ration for dairy cows are a major scarcity. And various concentration of urea in blocks positively affect milk and serum urea levels of indigenous dairy cows.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.9
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• pp.1099-1107
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• 2013

This study proposes a weight reduction design for urban transit, specifically, a Korean EMU carbody made of aluminum extrusion profiles, according to size optimization and useful material changes. First, the thickness of the under-frame, side-panels, and end-panels were optimized by the size optimization process, and then, the weight of the Korean EMU carbody could be reduced to approximately 14.8%. Second, the under-frame of the optimized carbody was substituted with a frame-type structure made of SMA 570, and then, the weight of the hybrid-type carbody was 3.8% lighter than that of the initial K-EMU. Finally, the under-frame and the roof-panel were substituted with a composite material sandwich to obtain an ultralight hybrid-type carbody. The weight of the ultralight hybrid-type carbody was 30% lighter than that of the initial K-EMU. All the resulting carbody models satisfied the design regulations of the domestic Performance Test Standard for Electrical Multiple Unit.