• Interaction and multiscale mechanics
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• v.5 no.2
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• pp.105-114
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• 2012

The study of rigid roadway pavement under dynamic traffic loads with variable velocity is investigated in this paper. Rigid roadway pavement is modeled as a rectangular damped orthotropic plate supported by elastic Pasternak foundation. The boundary supports of the plate are the steel dowels and tie bars which provide elastic vertical support and rotational restraint. The natural frequencies of the system and the mode shapes are solved using two transcendental equations, obtained from the solution of two auxiliary Levy's type problems, known as the Modified Bolotin Method. The dynamic moving traffic load is expressed as a concentrated load of harmonically varying magnitude, moving straight along the plate with a variable velocity. The dynamic response of the plate is obtained on the basis of orthogonality properties of eigenfunctions. Numerical example results show that the velocity and the angular frequency of the loads affected the maximum dynamic deflection of the rigid roadway pavement. It is also shown that a critical speed of the load exists. If the moving traffic load travels at critical speed, the rectangular plate becomes infinite in amplitude.

• Journal of Trauma and Injury
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• v.35 no.4
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• pp.287-290
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• 2022

Gastric artery bleeding after blunt trauma is rare. In such cases, if vital signs are stable, angiographic embolization may be performed. Although gastric artery embolization is known to be safe due to its anatomical properties, complications may occur. We report a case of gastric necrosis after gastric artery embolization in a patient with blunt abdominal trauma. The 55-year-old male patient was found with gastric arterial bleeding after a traffic accident. His vital signs were stable, and gastric artery embolization was performed. Gastric necrosis was subsequently found, which was treated surgically.

• Steel and Composite Structures
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• v.48 no.2
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• pp.145-161
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• 2023

This study investigates the influences of porosity on the stability of the orthotropic laminated plates under uniaxial and biaxial loadings based on the hyperbolic shear deformation theory. Three different porosity distribution are considered with three specific functions through the plate thickness. The stability equations of porous orthotropic laminated plates are derived by the virtual work principle. Applying the Galerkin method to partial differential equations, the critical buckling load relation of porous orthotropic laminated plates is obtained. After validating the accuracy of the proposed formulation in accordance with the available literature, a parametric analysis is performed to observe the sensitivity of the critical buckling load to shear deformation, porosity, orthotropy, loading factor, and different geometric properties.

• Journal of Korean Tunnelling and Underground Space Association
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• v.9 no.2
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• pp.157-169
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• 2007

This study aimed to quantify the deterioration of tunnel structural members such as concrete lining and shotcrete lining after a tunnel fire accident by measuring their mechanical properties between $300^{\circ}C$ and $1,000^{\circ}C$. From the experiments, it was revealed that the critical temperature where mechanical properties start to decrease linearly was approximately $300^{\circ}C$. In addition, the other critical temperature where macro-cracks are induced in specimens was around $600^{\circ}C$. From a series of regression analysis, the optimum regression function with correlation coefficients over 0.99 for mechanical properties at different temperature levels was obtained as the Boltzmann function. Finally, a schematic diagram to estimate temperature distribution inside structural members as well as their mechanical properties at corresponding temperature levels quantitatively was newly proposed for RABT and RWS fire scenarios.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2810-2818
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• 2009

In order to examine the characteristic of shallow failure in cut slopes composed of weathered granite soil, this study calculated critical permeability coefficient according to rainfall characteristic in Korea, performed stability analysis according to the representative physical properties of weathered granite soil distributed in Korea such as horizontal distance to the failure surface of cut slope, slope inclination, slope height, and the depth of wetting by rainfall, and analyzed the results. In the results of analyzing critical permeability coefficient, when the local rainfall characteristic was considered, the maximum critical permeability coefficient was $7.16{\times}10^{-4}cm/sec$. We judged that shallow failure according to wetting depth should be considered when rainfall below the critical rainfall intensity lasts longer than the minimum rainfall duration in cut slopes composed of weathered granite soil, which had a critical permeability coefficient lower than the maximum critical permeability coefficient. Furthermore, using simulated failure surface, this study could understand the characteristic of shallow failure in cut slopes based on the change in slope safety factor according to horizontal distance, wetting depth, and strength parameter.

• Advances in Traditional Medicine
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• v.6 no.4
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• pp.286-292
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• 2006

In this study, we evaluated the antiproliferative effects of Panax notoginseng, ginsenoside Rb1, and notoginsenoside R1 in the human breast carcinoma MCF-7 cell line. Our results indicated that both Panax notoginseng radix extract (NRE) and Panax notoginseng rhizoma extract (NRhE) possess significant antiproliferative activities in MCF-7 cells. Compared to control group (100%), at the concentrations of 0.05, 0.5, and 1.0 mg/ml NRE, cell growth was concentration-dependently reduced to 81.0 ${\pm}$ 6.1 (P < 0.01), 34.2 ${\pm}$ 4.8 (P < 0.001), and 19.3 ${\pm}$ 1.9 (P < 0.001), respectively. Similar results with NRhE at concentrations of 0.5 and 1.0 mg/ml were obtained in these MCF-7 cells. To identify the responsible chemical constituent, we tested the antiproliferation effects of two representative saponins, ginsenoside Rb1 and notoginsenoside R1, on the MCF-7 cells. The data showed that ginsenoside Rb1 was endowed with antiproliferative properties, while notoginsenoside R1 did not have an inhibitory effect in the concentrations tested. Our studies provided evidence that Panax notoginseng extracts and ginsenoside Rb1 may be beneficial, as adjuvants, in the treatment of human breast carcinoma.

• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.45-51
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• 2013

Short beam tests of GFRP and CFRP specimens exposed to high temperature were conducted to measure the inter-laminar shear strength. For the phase I test, the exposure time and temperature were varied to measure reduction in the strength due to the applied conditions. As a results, the critical temperature was found to $270^{\circ}C$ for the both FRP reinforcements. The high temperature, which causes 50% loss of inter-laminar shear strength, is defined as the critical temperature in this study. It should be noted that the critical temperature for the inter-laminar shear strength is mainly dependent on resin properties not on fiber type. In the phase II test, the effect of exposure time was investigated at intervals of 0.25hour for the critical temperature. All test results demonstrate that the exposure time effect is not significant compared to the maximum exposure temperature, but it is not negligible and, moreover, is significant at the critical temperature.

• Journal of Welding and Joining
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• v.25 no.4
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• pp.35-41
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• 2007

In kinetic spraying process, the critical velocity is an important criterion which determines the deposition of a feedstock particle onto the substrate. In other studies, it was experimentally and numerically proven that the critical velocity is determined by the physical and mechanical properties and the state of materials such as initial temperature, size and the extent of oxidation. Compared to un-oxidized feedstock, oxidized feedstock required a greater kinetic energy of in-flight particle to break away oxide film during impact. The oxide film formed on the surface of particle and substrate is of a relatively higher brittleness and hardness than those of general metals. Because of its physical characteristics, the oxide significantly affected the deposition behavior and critical velocity. In this study, in order to investigate the effects of oxidation on the deposition behavior and critical velocity of feedstock, oxygen contents of Al feedstock were artificially controlled, individual particle impact tests were carried out and the velocities of in-flight Al feedstock was measured for a wide range of process gas conditions. As a result, as the oxygen contents of Al feedstock increased, the critical velocity increased.

• Journal of the Korea Fashion and Costume Design Association
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• v.3 no.2
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• pp.5-21
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• 2001

The intellectual properties right are becoming very critical issues in domestic fashion industries and also international trade. Although it is true that intellectual properties rights are commonly infringed in fashion industry, none of researches has been done for this matter. The present study is to analyze the patterns of infringement by case analysis, which was limited to trademark and trade dress. As a result, in case of trademarks, counterfeiting was relatively clear case, but it is generally investigated by prosecutes whereas the judgement of similar trademark has been taken by legal lawsuit. In case of industrial design(trade dress) most of disputes were related to textile design and modified Korean tradition dress. Reflecting the short history of protection of intellectual properties rights many informations and legal regulations should be established by te government and by the association of fashion related industry.

• Korean journal of food and cookery science
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• v.20 no.2
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• pp.158-163
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• 2004

The purpose of this study was to determine the organoleptic properties of mushroom pickles made at various compounding ratios according to central composite design for optimum organoleptic properties. In this study, various kinds of mushroom pickle were made at different compounding ratios of vinegar, sugar and salt-critical ingredients of the pickle recipe and the products were presented to an expert panel, who graded the subjects in 7 degrees for 5 items: color, flavor, hardness, taste and overall quality. As a result of sensory quality, mushroom pickles with 300g of vinegar, 150g of sugar and 60g of salt achieved the highest grade. Meanwhile, the results of Response Surface Methodology were different from the sensory quality results, showing that the optimum mixing conditions for overall organoleptic properties of mushroom pickle were 279.58g of vinegar, 179.34g of sugar and 59.09g of salt. (Ed- based on this conflict in results, I suggest that you make a final recommendation, of either the first, the second, or perhaps an intermediate, ratio)