• The Journal of Advanced Prosthodontics
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• v.8 no.2
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• pp.158-166
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• 2016

PURPOSE. The aim of this study was to determine the fracture resistance and the mode of fracture of endodontically treated teeth restored with different fiber posts and all-ceramic crowns. MATERIALS AND METHODS. Two glass fiber reinforced post systems in two different sizes and polyethylene fiber ribbon in two different thicknesses (n=10) were used. The specimens, restored with all-ceramic crowns, were subjected to a compressive load (in N) delivered at a 130-degree angle to the long axis until a fracture could be noted. The results were analyzed statistically with a One-Way ANOVA test (P<.05). RESULTS. Statistically significant differences were observed between the mean fracture resistance values of Postec, Snowlight, and Kerr Connect thin specimens (P<.0095). The Postec results (395.70 N) were found to be significantly higher than the others. No statistical difference was observed among the thick specimens (P<.2657). The mean fracture resistance values of the Snowlight thick samples were found to be higher than those of the Snowlight thin samples. The specimens were always fractured around the cemento-enamel junction at the palatinal side. No post fracture was observed for the thin Snowlight and Kerr Connect specimens or for the thick Postec and Kerr Connect specimens. Among the common failure types of the specimens, the worst was observed to be the root fracture failure. The highest post dislodgement failure result (80%) was obtained from the thin Kerr Connect specimen. CONCLUSION. In terms of optimizing fracture resistance, the fiber post size selection should be done according to the forces applied to the restored teeth.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.371-376
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• 2000

In this study, the computational method is presented to simulate the hemodynamics of the patients after the Fontan procedure. The short-term feedback control models are implemented to assess the hemodynamic responses of the patients exposed to the stresses such as gravitational effect or hemorrhage. To construct the base line of the Fontan model, we assume an increase in venous tone, in heart rates, and in systemic resistance that are based on the clinical observations. For the verification of the present method we simulate the LBNP (lower body negative pressure) test for the normal and the Fontan model and we compare these with experimental data. Computational results show that the diastolic ABP(arterial blood pressure) increases but the systolic ABP decreases during LBNP. The increase in heart rate is due to the control system activated by the decreased mean ABP and CVP(central venous pressure). In case of the Fontan model, the increased venous tone is the reason of the diminished CVP change during LBNP. We also simulate 20% hemorrhage stress to the patient after the Fontan procedure and these results are compared with the experimental and the existing computational one. Computational results on the hemodynamics of patients after the Fontan procedure show that the mean ABP and cardiac output decrease. Heart rate and systemic resistance increase to compensate for the decrease in ABP. The sensitivity analysis according to the conduit resistance is also presented to delineate the effects of the local blood flow resistance. The cardiac output decreases according to the increase of the conduit resistance. The 50% increase in the conduit resistance causes about 3% decrease of cardiac output.

• Journal of the Korean Society of Safety
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• v.31 no.6
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• pp.25-31
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• 2016

This paper has analyzed the structure, applicable regulations and the resistance characteristics of insulation ring type of CSST (Corrugated Stainless Steel Tubing for Gas). With the flammability test conducted in accordance with KS C IEC 60811-1-1, the evaluation of insulation resistance, temperature characteristics, and reliability has been conducted. An insulation ring type CSST consists of protective coating, tube, nut, insulation ring, packing, socket, and ball valve. Connecting an insulation ring type CSST to gas tubings for gas appliance is not permitted, moreover, the product shall be installed inside a sleeve pipe in case of buried installation such as the ceiling. Damages on protective coating and tube were detected when fire was applied to the test sample with a portable torch for 60 seconds. The insulation resistance of a normal product was $49.59M{\Omega}$, while that of the product completed the flammability test reduced to $9.21M{\Omega}$. The mean insulation resistance within the confidence Interval of 95% using the mini tap program 17 was $49.59M{\Omega}$ and the mean insulation resistance within the confidence interval reduced to $9.21M{\Omega}$. In the normal distribution analysis of 95% confidence interval, the value-P of the normal product was stable at 0.075 and AD(Anderson-Darling) statistic value was turned out to be 0.063, which is very normal, and the standard deviation was analyzed as 0.2586. The value P of the product completed the flammability test resulted in 0.005, the AD was 1.355 and the standard deviation reduced to 0.07908.

• Corrosion Science and Technology
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• v.12 no.5
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• pp.220-226
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• 2013

The uncertainty in statistical noise resistance measurement was evaluated for a type 316 stainless steel in NaCl solutions at room temperature. Sensitivity coefficients were determined for measurands or variables such as NaCl concentration, pH, solution temperature, surface roughness, inert gas flow rate and bias potential amplitude. The coefficients were larger for the variables such as NaCl concentration, pH, inert gas flow rate and solution temperature, and they were the major factors increasing the combined standard uncertainty of noise resistance. However, the contribution to the uncertainty in noise resistance measurement from the above variables was remarkably low compared to that from repeated measurements of noise resistance, and thus, it is difficult to lower the uncertainty in noise resistance measurement significantly by lowering the uncertainties related with NaCl concentration, pH, inert gas flow rate and solution temperature. In addition, the uncertainty in noise resistance measurement was high amounting to 17.3 % of the mean, indicating that the reliability in measurement of noise resistance is low.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.3
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• pp.413-420
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• 2018

This paper documents the result of a preliminary analysis on the influence of hull-ice friction coefficient on model resistance and power predictions and their correlation to full-scale measurements. The study is based on previous model-scale/full-scale correlations performed on the National Research Council - Ocean, Coastal, and River Engineering Research Center's (NRC/OCRE-RC) model test data. There are two objectives for the current study: (1) to validate NRC/OCRE-RC's modeling standards in regarding to its practice of specifying a CFC (Correlation Friction Coefficient) of 0.05 for all its ship models; and (2) to develop a correction methodology for its resistance and propulsion predictions when the model is prepared with an ice friction coefficient slightly deviated from the CFC of 0.05. The mean CFC of 0.056 and 0.050 for perfect correlation as computed from the resistance and power analysis, respectively, have justified NRC/OCRE-RC's selection of 0.05 for the CFC of all its models. Furthermore, a procedure for minor friction corrections is developed.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.1
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• pp.85-95
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• 1996

Although the specific resistance to filtration is the most frequently employed means for characterizing dewaterability of a sludge, it presently is not possible to design nor to prediet performance of dewatering facilities using traditional linearized parabolic filtration equation, that is, the specific resistance model because of theoretical and practical inadequacies of the concept. Limitations of the specific resistance model reflect the need to examine fundamental sludge properties and filtration behaviors affecting dewaterability. From this study, two major limitations of the specific resistance model were noted. First, specific resistance values are very dependent on the sludge concentration because of the variations of particle size distribution and cake clogging to occur when surface area mean diameter is less than $25{\mu}m$ for activated sludge, $18{\mu}m$ for water treatment plant sludge. Second, nonparabolic filtration behavior can result from cake clogging, caused by the migration of fine particles into the cake pores, accelated by skin effect with highly compressible sludges.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.721-727
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• 2000

Impedance method was carried out to design the electrode that can measure the void fraction of the bubbly flow in pool reservoir. To find out the optimum electrode shape, Styrofoam-tests were performed in a specially designed acrylic reservoir. Three kinds of electrodes were designed to compare the characteristics of water-air flow. The resistance was increased as the void fraction increased and the capacitance was decreased as the void fraction increased. The resistance is a main parameter to express the nature of the water-air flow in impedance method. Almost all the values of impedance were involved in resistance. The degree of deviation from the mean-resistance values showed reasonable results. Electrode type-I expressed excellent results among the three electrode shapes. The impedance values in void fraction 0-10% were similar to those of Maxwell's equation. But the impedance values in void fraction 10-20% were not similar to those of Maxwell' equation because of the edge effect near electrode.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.4
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• pp.35-37
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• 1979

To investigate the genetic system in resistance to powdery mildew winter wheat cultivar Diplomat which has stable field resistance was crossed with high yielding susceptible winter type Caribo and Hayman's generation mean analysis technique was employed. Mildewing rate on flag-leaf at both heading-flowering and ripe stages were recorded according to lame's quantitative scale. The result indicated that additive gene effect was more important and significant role in the inheritance of resistance while dominant gene effect was minimum, and digenic interations were absent. Narrow sense heritability of resistance at ripe stage was higher than that of heading-flowering stage.

• Journal of Sericultural and Entomological Science
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• v.24 no.1
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• pp.28-31
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• 1982

Flacherie virus (FV) is an important pathogen in the silkworm, which often gives serious damage to farmers for cocoon production. The inbred parents and F$_1$'s from an eight-parent diallel were examined to determine the inheritance of resistance to flacherie virus in the silkworm. Three resistant (R), two intermediate (M) and three susceptible (S) inbreds were used in the diallel with no reciprocals. Mean resistance was measured by survival rates of larvae which were fed on mulberry leaves sprayed with diluted mid-gut homogenate of FV infected larvae. Broad-sense heritability was obtained according to inbreds and F$_1$ family performance. Estimation of general (GCA) and specific combining ability (SCA) was made according to Griffing's Model 1, Method 2. Mean FV resistance of F$_1$ family displayed additive effect of the major gene, while heterotic effect was not significant. Considerable variation in FV resistance within F$_1$ groups of R$\times$S and S$\times$S indicated that action of minor genes for FV resistance may have been involved. FV resistance of inbreds perse and predominant effect of the major gene over minor gene(s) satisfactorily predicted the FV resistance of the hybrids. Broadsense heritability value of FV resistance on the basis of F$_1$ family performance averaged 93%, which suggested that environmental effects might have not been important in this experiment. GCA was highly significant for FV resistant among inbreds. GCA effect of 13.1 in Jam 108 was highest and -17.7 in Gyeongchu lowest. Effective selection for high FV resistance would be possible, using inbreds with high GCA effect and low GCA variance. SCA was significant among hybrids. High SCA effect in the hybrid of Geumho$\times$Mudeung (13.7) and Hansaeng #4$\times$Jam 115 (11.6) indicated that the interaction effect of minor genes for resistance to FV in the silkworm could be exploited by standard silkworm breeding procedures.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.225-231
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• 2009

The purpose of this study was to compare the effectiveness of Dangkisoo-san(Dangguixu-san) and Gamihwalhyul-tang(Jiaweihuoxie-tang) herb-medication for the Traffic accident patient group with the effectiveness of common herb-medication for the general patient group by using 7-Zone-Diagnostic System. Two groups were selected from those who took the CP-6000A test in College of Oriental Medical Hospital of Sangji University from March 2007 to January 2008. Mean values of Factor AA on Skin Resistance Variability(SRV) of two groups were compared. The mean values of the deviation between measurement and 50 in pre-examination was higher than those of post-examination. Especially, there were remarkable difference between the mean values of the deviation between measurement and 50 in pre-examination and those of post-examination within the general patient group. When we compare pre-examination with post-examination in each area, 2 areas have remarkable difference within the general patient group. The mean values of positive deviation in pre-examination was higher than those of post-examination within both group. Especially, the TA patient group was remarkable. The other side the mean values of negative deviation in pre-xamination was remarkably higher than those of post-examination within the general patient group. By contraries the mean values of negative deviation in pre-examination was lower than those of post-examination within the TA patient group. These results suggest that Dangkisoo-san(Dangguixu-san) and Gamihwalhyul-tang(Jiaweihuoxie-tang) herb-medication will be less effective for chronic and weak traffic accident patients.