• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3313-3319
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• 2023

A phenomenological study on CHF in a bilaterally heated annulus with equal heat flux on both sides was experimentally performed. The working fluid of the present test was R-134a. Variation characteristics of CHF and transition of CHF occurrence location were investigated under different pressure, mass flux and quality conditions. With the increase of critical thermodynamic quality, it was found that CHF first occurred on the outer surface of the annulus, then simultaneously occurred on both sides, and finally occurred on the inner surface at relatively high critical quality. After the CHF location transitioned to the inner rod, the sharp fall of CHF in the limiting critical quality region was observed. The critical quality corresponding to the CHF location transition decreased with the increase of mass flux and pressure. Besides, CHF in tube, internally heated, externally heated and bilaterally heated annuli were compared under the same hydraulic diameter conditions. The present study is conducive to improving the understanding of complicated CHF mechanism in bilaterally heated annulus, enriching the experimental database, and providing evidence for developing accurate CHF mechanism model for annuli.

• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1244-1249
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• 2024

A combination of flow-accelerated corrosion (FAC) tests and corresponding computational fluid dynamics (CFD) tests were performed to determine the hydrodynamic parameters that could help predict the highly susceptible location to FAC in the elbow section. The accelerated FAC tests were performed on a specimen containing elbow sections fabricated using commercial 2-inch carbon steel pipe. The tests were conducted at flow rates of 9 m/s under the following conditions: water temperature of 150 ℃, dissolved oxygen <5 ppb, and pH 7. Thickness reduction of the specimen pipe due to FAC was measured using ultrasonic testing. CFD was conducted on the FAC test specimen, and the turbulence intensity, and shear stress were analyzed. Notably, the location of the maximum hydrodynamic parameters, that is, the wall shear stress and turbulent intensity, is also the same location with maximum FAC rate. Therefore, the shear stress and turbulence intensity can be used as hydrodynamic parameters that help predict the FAC-induced wall-thinning rate. The results provide a method to identify locations susceptible to FAC and can be useful for determining inspection priority in piping systems.

• Journal of Haehwa Medicine
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• v.16 no.1
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• pp.157-166
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• 2007

Objectives : The purpose of this study is to search for more effective methods of diagnosis and treatment of Fracture. Methods : Literature review on Fracture in view of oriental and western medicine. Conclusions : Fracture is classified by anatomical location, grade, shape of line, displacement and cause. The symptom of Fracture is pain, tenderness, deformity, attitude, abnormal mobility, crepitus, neurovascular injury. Fracture is not the same in Healing process by location. The age, endocrine system, chronic debilitating disease, stabilization is effect on healing period and process. Treatment of Fracture is classified emergency care, definite treatment and rehabilitation.

• Journal of Welding and Joining
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• v.18 no.1
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• pp.104-109
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• 2000

Based on the principle of complementary energy, an analytical method is developed which focused on the end effects for determining thermal stress distributions in the clad beam. This method gives the stress distributions which completely satisfy the stress-free boundary condition at the edge. Numerical results shows that shear and peeling stress at the interface between the substrate and clad are significant near the edge and become negligible in the interior region. Even thought the relative location where the maximum or minimum stresses take place moves to interior as the length of the beam becomes smaller, the absolute location from the free end and the value of these stresses are the same in spite of the variation of the length of beam.

• Proceedings of the KWS Conference
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• 1999.10a
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• pp.306-309
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• 1999

Based on the principle of complementary energy, an analytical method is developed which focused on the end effects for determining thermal stress distributions in the claded beam. This method gives the stress distributions which completely satisfy the stress-free boundary condition at the edge. Numerical result shows that shear stress and peeling stress at the interface between the substrate and clad are significant near the edge and become negligible in the interior region. Even though the relative location where the maximum or minimum stresses take place moves to interior as the length of the beam become smaller, the absolute location from the free end and the value of these stresses are the same in spite of the variation of the length of beam.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.7 no.2
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• pp.25-30
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• 2001

Corrugated board is composed of cellulose fibers which are arranged with the same direction as the board manufactured. The direction is classified with machine direction (MD) and cross-machine direction (CD). Therefore, corrugated board is orthotropic material that has totally different strength properties at each direction and especially, at machine direction, the mechanical properties of fiberboard is superior. The compression strength of the corrugated fiberboard boxes is very important information to the manufacturers and the end users. This study was carried out to design the optimum pattern, size, and location of ventilating hole for ventilating container through the finite element analysis. The optimum pattern and location of ventilating and hand hole were vertical oblong, a short distance to the right and left from the center of panel, and center or a short distance to the top of both sides, respectively. We identified the effect on both stress dispersion and stress level from the analysis of redisigned hand hole.

• Journal of environmental and Sanitary engineering
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• v.18 no.3 s.49
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• pp.11-20
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• 2003

There are two ways of reducing air pollution. One is the approach of the pollutant source control and the other one is the traffic demand decreasing approach. This study is focusing on the approach of land use planning and optimal location of urban facilities because those are the basic cause to generate transportation demands. So, the purpose of this study would be to analyze the changes of NOx and CO distribution on environmental air by functional hierarchy of urban roads and to make evaluation model of 'Transportation-Land Use -Air Pollution'. It will contribute to improve the air pollution level at same actual traffic generation according to different location.

• Journal of Broadcast Engineering
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• v.12 no.2
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• pp.112-119
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• 2007

Reversible data embedding theory has marked a new epoch for data hiding and information security. Being reversible, the original data and the embedded data as well should be completely restored. Difference expansion transform is a remarkable breakthrough in reversible data hiding scheme. The difference expansion method achieves high embedding capacity and keeps the distortion low. This paper shows that the difference expansion method with simplified location map, and new expandability and changeability can achieve more embedding capacity while keeping the distortion almost the same as the original expansion method.

• Earthquakes and Structures
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• v.8 no.5
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• pp.1113-1126
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• 2015

A damage localization algorithm based on Operational Deformed Shapes and known as Interpolation Damage Detection Method, is herein applied to the finite element model of a cable stayed bridge for detecting and localizing damages in the stays and the supporting steel beams under the bridge deck. Frequency Response Functions have been calculated basing on the responses of the bridge model to low intensity seismic excitations and used to recover the Operational Deformed Shapes both in the transversal and in the vertical direction. The analyses have been carried in the undamaged configuration and repeated in several different damaged configurations. Results show that the method is able to detect the damage and its correct location, provided an accurate estimation of the Operational Deformed Shapes is available. Furthermore, the damage detection algorithm results effective also when damages coexist at the same time at several location of the cable-stayed bridge members.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.431-432
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• 2018

Humans have used acceleration sensors to perceive behavior. Using the application principles of inertia sensor such as acceleration and gyro sensors, the sensor indirectly measures movement through forces applied on a three-dimensional axis. This may result in different results depending on the location of the sensor in possession, even in the same way. The sensor, which is also mounted on popular smartphones, measured different values of acceleration sensors, whether in hand or in pocket, which are commonly used by people.