• Food Engineering Progress
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• v.22 no.4
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• pp.381-385
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• 2018

Various rheological methods to measure the hardness of instant cooked rice by a texture analyzer were investigated and compared. Specifically, instant white rice samples with a wide range of hardness were subjected to four different rheological tests with disk, cylinder, rod, and cone probe whose results were inter-correlated. All the measurements demonstrated that the hardness of instant rice was reduced with increasing moisture content and showed negatively linear relationships. Out of the four tests applied in this study, the highest coefficient of correlation ($R^2=0.9268$) was observed distinctly in the cone probe test, where both compressive and shear forces can be applied to deform individual rice grains. However, the cylinder probe test had the lowest coefficient of correlation ($R^2=0.7247$) because it may be ineffective in causing direct deformation of individual rice grains. Furthermore, when the hardness values (N) were converted to stress (Pa), highly linear correlations ($R^2{\approx}0.99$) were observed between the tests with similar probe geometry and force application.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.4 no.2
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• pp.29-33
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• 2008

As the measures of nuclear power plant utilities and manufacturers to reduce the defects of tube expansion region during manufacturing steam generators, many types of NDEs(Non-Destructive Examinations) are conducted to inspect the expansion region. The expansion region of tube is subject to degrade because of stress concentration induced by tube expansion, sludge pile and high temperature. So the inspections for tube expansion region have been reinforced. Liquid penetrant test, helium leak test, Bobbin profile test and hydraulic test are performed to confirm the integrity of tube expanded by hydraulic expansion method. Liquid penetrant test and helium leak test are used to inspect seal weld region on tubesheet end part. Bobbin Profile test is used to inspect fully the expanded region of steam generator tube. Hydraulic test finally verifies the integrity of seal weld region on tubesheet end part.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.377-381
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• 2004

Electrical conductivity of Al-Si-Cu-Mg alloy foams of various density produced in powder metallurgical method has been measured using two probe electrical conductivity measurement method. Compressive mechanical properties such as elastic modulus and plastic plateau stress of foams were evaluated from electrical conductivity using power law relation and scaling laws of foam properties. Uni-axial compression test was also performed. Experimentally measured elastic modulus and plastic plateau stress were compared with the values evaluated from electrical conductivity. The computed values were in good agreement with the experimental result.

• The Journal of Engineering Geology
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• v.23 no.4
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• pp.511-517
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• 2013

The Field Velocity Probe (FVP) has been widely applied to determine the various characteristics of soils. This study seeks to estimate soil consolidation characteristics using an FVP and to increase its application in the field. The specimens were extracted from depths of 3 and 6 m at the study site, an area of soft clay in Incheon. In laboratory testing, the specimens were placed in an improved oedometer cell to measure shear wave velocity, and statistical analysis was performed to compare the results of effective stress and shear wave velocity. FVP enables increased resolution in the field because it measures the shear wave velocity every 20 cm. To estimate the condition of consolidation, we compared the results of shear wave velocities between those obtained in the laboratory and those in the field. The field conditions are used to analyze overconsolidated and normally consolidated soils at depths of 3 and 6 m, respectively. The results show that FVP is a suitable method for estimating the degree of consolidation.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.6
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• pp.519-523
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• 2013

A steam generator (SG) tube is an important component of a nuclear power plant (NPP). It works as a pressure boundary between the primary and secondary systems. The integrity of a SG tube can be assessed by an eddy current test every outage. The eddy current technique(adopting a bobbin probe) is currently the main technique used to assess the integrity of the tubing of a steam generator. An eddy current signal analyst for steam generator tubes continuously analyzes data over a given period of time. However, there are possibilities that the analyst conducting the test may get tired and cause mistakes, such as: missing indications or not being able to separate a true defect signal from one that is more complicated. This error could lead to confusion and an improper interpretation of the signal analysis. In order to avoid these possibilities, many countries of opted for automated analyses. Axial ODSCC (outside diameter stress corrosion cracking) defects on the tubes of OPR1000 steam generators have been found on the tube that are in contract with tube support plates. In this study, automated analysis software called CDS (computer data screening) made by Zetec was used. This paper will discuss the results of introducing an automated analysis system for an axial ODSCC on the tubes of an OPR1000 steam generator.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.2
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• pp.130-134
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• 2019

In this paper, a laser-based non-contact load cell is newly developed for measuring forces in prestressed concrete tendons. First, alumina particles have been sprayed onto an empty load cell which has no strain gauges on it, and the layer has been used as a passive stress sensor. Then, the spectral shifts in fluorescence spectroscopy have been measured using a laser-based spectroscopic system under various force levels, and it has been found that the relation of applied force and spectral shift is linear in a lab-scale test. To validate the field applicability of the customized load cell, a full-scale prestressed concrete specimen has been constructed in a yard. During the field test, it was, however, found that the coating surface has irregular stress distribution. Therefore, the location of a probe has to be fixed onto the customized load cell for using the coating layer as a passive stress sensor. So, a prototype customized load cell has been manufactured, which consists of a probe mount on its casing. Then, by performing lab-scale uniaxial compression tests with the prototype load cell, a linear relation between compression stress and spectrum shift at a specific point where laser light had been illuminated has been detected. Thus, it has a high possibility to use the prototype load cell as a force sensor of prestressed concrete tendons.

• Journal of Power System Engineering
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• v.5 no.1
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• pp.21-26
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• 2001

This paper represents the turbulent intensity, the turbulent kinetic energy and Reynolds shear stress in the X-Y plane of cone type swirl gas burner measured by using X-probe from the hot-wire anemometer system. The experiment is carried out at flowrate 350 and $450{\ell}/min$ respectively in the test section of subsonic wind tunnel. The turbulent intensity and the turbulent kinetic energy show that the maximum value is formed in the narrow slits distributed radially on the edge of a cone type swirl burner, hence, the combustion reaction is anticipated to occur actively near this region. And the turbulent intensities ${\upsilon}\;and\;{\omega}$ are disappeared faster than the turbulent intensity u due to the inclined flow velocity ejecting from the swirl vanes of a cone type baffle plate of burner. Moreover, the Reynolds shear stress $u{\upsilon}$ is distributed about three times as large as the Reynolds shear stress $u{\omega}$ in the outer region of the cone type gas burner.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.6
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• pp.738-744
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• 2011

The reliability of blade root fixing section is required to endure the centrifugal force and vibration stress for the last stage blade of steam turbine in thermal power plant. Most of the domestic steam turbine last stage blades have finger type roots. The finger type blade is very complex, so the inspection had been performed only on the exposed fixing pin cross-section area due to the difficulty of inspection. But the centrifugal force and vibration stress are also applied at the blade root finger and the crack generates, so the inspection method for finger section is necessary. For the inspection of root finger, inspection points were decided by simulating ultra-sonic path with 3D modeling, curve-shape probe and fixing jig were invented, and the characteristics analysis method of ultrasonic reflection signal and defect signal disposition method were invented. This invented method was actually executed at site and prevented the blade liberation failure by detecting the cracks at the fingers. Also, the same type blades of the other turbines were inspected periodically and the reliability of the turbine increased.

• Journal of Sasang Constitutional Medicine
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• v.20 no.3
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• pp.151-163
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• 2008

1. Objective This study was done to identify the anti-stress effect of Hyeongbangdojeok-san (HDS), Yanggyeoksanhwa-tang(YST) in Soyangin. 2. Methods Experimental animals were composed of YST, HDS+stress groups which were administered each by 200mg/kg, 400mg/kg and the Saline+stress group. On the 1st day, making the rats forced swim and on the 2nd day, applying Forced swimming test to the rats. After FST, the levels of Corticosterone in the blood were measured. For the study of learning retardation, memory ability and anxiety reaction, experimental animals were composed of YST, HDS+restraint stress groups which were administered each by 400mg/kg, no stress group and the Saline+restraint stress group. Restraint stress were applied 2 hours a day for 3 weeks. On the last day of the 3rd week, Elevated Plus Maze(EPM) was applied to the groups and Morris Water Maze(MWM) was applied to the groups for 7 days. 3. Results 1. As the results of measuring FST which reflects depression, the YST+stress group and the HDS+stress group showed significant effect in comparison with the Saline+stress group. The levels of Corticosterone in the blood were decreased only in the 400mg/kg YST+stress group. 2. As the results of measuring how long EPM which reflects anxiety reaction stayed in the open arm, there was the trend which can suppress anxiety reaction in the HDS+restraint stress group bur no statistical significance. But there was any suppression of anxiety reaction in the YST+restraint stress group. 3. According to the result of MWM, the saline+restraint stress group showed the learning retardation which means increased time arriving at goal compared to the normal group at the second and third day of measurement. On the contrary, a learning retardation was significantly decreased in the YST+restraint stress group at the third day of measurement. 4. Among the Probe trial test a memory loss occurred in the saline+restraint stress group, but memory ability was significantly increased in the YST+restraint stress group. 4. Conclusion: As the results above, Soyangin Yanggyeoksanhwa-tang has significant influence to the antidepression effect, the learning retardation, the anxiety reaction and also in the Hormone level. Hyeongbangdojeok-san has significant influence to the antidepression effect, in the Hormone level, bur not to the learning retardation and anxiety reaction. prefer to drink cold water, and who are suffering from chronic gastritis.

• The Korea Journal of Herbology
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• v.21 no.2
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• pp.63-75
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• 2006

Objectives : We investigated the effects of Liriopis Tuber on the nervous protection. Methods : We measured the reaction behavior with EPM(Elevated Plus Maxe) and MWM(Morris Water Maze) after applying restraint stress to rats. Also, the degrees of AchE generation were measured with immunohistochemical method in the regions of hippocampus, and the degree of TH generation in the regions of VTA and LC, respectively. Results : 1. As the results of measuring how long EPM which reflects anxiety reaction stayed in the open arm, there was the trend which can suppress anxiety reaction in the MMD+stress group(Liriopis Tuber+stress) but no statistical significance. The counting results how many EPM passed between opened and closed arm showed suppression trend against a physical activity in the saline+stress group but there was no statistical significance. 2. According to the result of MWM, the saline+stress group showed the learning retardation which means increased time arriving at goal compared to ti1e normal group at the second and third day of measurement. On the contrary, a learning retardation was significantly decreased in the MMD+stress group. Among the probe trial test a memory loss occurred in the saline+stress group, meanwhile memory ability was notably increased in the saline-stress group. 3. The degree of TH generation was investigated at the VTA and LC respectively after test animals treated with drug. In the saline+stress group, TH-immunoreactive cells were significantly increased, and these stress-induced TH increases were suppressed in the saline+stress group at the VTA region. However, the saline+stress group did not show any significant difference. 4. the degree of AchE generation was investigated at the CA3 of hippocampus. The saline+stress group showed that AchE-immunoreactive cells were significantly decreased. Those stress-induced reductions of AchE cells were meaningfully recovered in the saline+stress group. Although the cells showed recovery trend in the region of CA1 of hippocampus, statistical significance was not observed. Conclusion : The results of our study indicate that Liriopis Tuber can improve spatial memory ability of rats applied a restraint stress. This improvement of the spatial memory ability is considered to have an efficacy of nervous protection that Liriopis Tuber suppresses the generation of AchE in the hippocampus region and enhances the generation of TH in the VTA.