• Transactions of Materials Processing
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• v.20 no.2
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• pp.99-103
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• 2011

Many parameters influence the frictional behavior of steel sheet during stamping. The contact pressure between a die and a sheet during stamping is one of them. Thus, this parameter is investigated for high strength steel (HSS) sheets, which are widely used for auto body panels due to their potential for weight reduction. Since HSS extend the limits of contact pressure for mild steel, the effect of this parameter on friction cannot be ignored. To investigate the influence of contact pressure on the frictional behavior of steel sheets, a flat type of friction test was conducted on three different steel sheets under various contact pressures. For bare steel sheets, the curve representing the relationship between contact pressure and friction coefficient exhibits a U shape. Coated steel sheets show a similar tendency except at low contact pressure. For these materials, when the contact pressure is very low, the friction coefficient slightly increases with pressure before it starts to decrease. The test results show that the effect of contact pressure on frictional behavior of steel sheet is not negligible even for contact pressures that are lower than the strength of HSS sheet.

• Korean Journal of Human Ecology
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• v.11 no.3
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• pp.223-235
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• 2002

The purpose of this study was to examine the influences of the materialism of university students. The data were collected for 331 university students. The data were analyzed by the package of SPSS program. The methods of analyses included basic descriptive categorical analysis (frequencies, means, percentages) as well as t-test, one way ANOVA, and multiple regressions. To summarize major findings from the analysis: (1) A significant difference was found in the materialism of university students by the socio-economic variables such as the amount of pocket money. (2) A significant difference was found in the materialism of university students by more self-esteem than life satisfaction. (3) A significant difference was found in the materialism of university students by parent's materialism and competitive achievement pressure. (4) According to the multiple regression analysis, it was found that the materialism of university students was influenced by the order of self-esteem, parent's materialism and competitive achievement pressure.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.5
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• pp.120-125
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• 2015

This research aims to increase the reliability and reproducibility of the ambient cycling test by properly making corrections to the test procedure. The vessel (106 L) is initially filled with 70 L of water and horizontally placed on a balance. The pressure range inside the vessel varies from 2.5 to 25.9 MPa at the frequency of 6 cycles per minute. After reviewing the results, there was a temperature difference of approximately $10^{\circ}C$ between the air pocket and the water, and the upper part of the liner faced a repeated temperature change of $40^{\circ}C$. It is possible for the aluminum liner of the composite vessel to be damaged by such a sharp change in temperature. Additionally, as a result, no pass having anything to do with the purpose of the test would occur. Therefore, it is suggested that the air pocket be completely removed.

• Transactions of The Korea Fluid Power Systems Society
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• v.4 no.3
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• pp.1-6
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• 2007

The leakage generated from the clearance between the cylinder bore and the piston is one of the most serious problems in the hydraulic piston pump, and it even results in terrible decrease of the volume efficiency at a great velocity and high pressure. In this paper, the lubrication characteristic of the hydrostatic slipper bearing equipped in the hydraulic piston pump has been worked out by experimentation with three model bearings of different shape. Preparatory to this, not only the three models of piston-slipper were designed, but the corresponding experimental apparatus were also manufactured. As a result, it was verified that, according to the supply pressure, the hydrostatic bearing part of the slipper is severely affected by the pocket pressure, land pressure, oil film thickness, and leakage flow.

• Research in Community and Public Health Nursing
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• v.15 no.4
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• pp.517-527
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• 2004

Purpose: This research is to find a solution for educational work on high blood pressure control in public health centers by analyzing their current status. Method: It analyzed data from 133 public health centers that had been doing educational work on high blood pressure, through a questionnaire. Also, it developed recommendations by converging opinions from an expert group made of 25 people with nominal group technique. Result: The educational methods of public health centers did not make any approach to get to the goal of the work. The mass media education and campaign activities for the general public had just temporary and passive propensities. In education for patients, it did not use appropriate methods to present management techniques for diagnosis process of patients, medication management, self monitoring BP, and risk factors. Pocket book for monitoring high blood pressure was not focused on self-recording for self-management. The expert group recommended that educational materials for adults should be developed focusing on treatments and observance of risk factors through daily living, and those for children should be focused on basic understanding about diseases, and life style. Conclusion: Presenting direction and strategy of fundamental education work is needed for public health centers by giving them standard educational guidelines of managing high blood pressure nationally, and it is desirable that fundamental frameworks of educational materials should be developed and distributed by professional groups nationally.

• Fashion & Textile Research Journal
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• v.21 no.1
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• pp.75-87
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• 2019

The purpose of the study was to suggest a cycle wear top jersey improved in mobility. The study developed a new cycle wear with improvement in dissatisfaction factors by planning design, pattern and the functionality of fabric. Considering the amount of sweat and the necessities of compression part, the basic material, the additional compression material, and the mesh material were arranged differently according to areas. The assessment of the developed cycle wear was composed of wearing comfort evaluation by female cyclist, photo analysis and garment pressure evaluation. The developed cycle wear was evaluated and compared with the current cycle wear. As a result of wearing comfort evaluation, the developed cycle wear was evaluated as better than the existing ones in all part, particularly in the areas of reflection tape and materials, partial pressure, pocket size, and prevention of loss. Photo analysis was in agreement with the appearance evaluation of the participants. As a result of garment pressure evaluation, the front neck part was more comfortable and the upper arm, abdomen, and waist area showed higher pressure, so it partially supported the body. This study has significant meaning for developing a new cycle wear top, protecting the body and improving the exercise effect.

• Journal of Drive and Control
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• v.10 no.1
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• pp.14-20
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• 2013

In the high rotational speed and pressure state, the leakage flow rate of the axial piston pump is one of the serious problems and make great reasons to decrease the volume efficiency. In this study, tribology characteristics is clarified for the hydrostatic slipper bearing in the swash plate type axial piston pump, by means of theoretical analysis for the different shape of the hydrostatic slipper bearing. It was analyzed by Mathcad software and used equal conditions at $0^{\circ}$ swash plate angle in each model. The results show that performance characteristics of the swash plate type axial piston pump are significantly influenced by the shape of the hydrostatic slipper bearing.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.4
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• pp.522-527
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• 2008

On designing of hydrostatic bearing, load, quantity of oil, stiffness and friction load are considered as basic characteristics. For the analysis of these basic characteristics, pressure distribution by oil film is obtained. Speed of piston, clearance, leakage of oil, eccentricity, shape and roughness of bearing affect the results which are the analysis of basic characteristics of load, quantity of oil, stiffness and friction load. The relationship among those factors are required for optimum designing of hydrostatic bearing for machining tool. Reynold's Equation is calculated through finite element method. Load, leakage of quantity and pressure distribution as variation of length, land length ratio, eccentricity and axial velocity of bearing are investigated. Then optimum design variables are obtained.

• Journal of Radiation Protection and Research
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• v.21 no.1
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• pp.1-7
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• 1996

In this paper, we discussed the fabrication and characterization of bulk type CdZnTe detector for pocket surveymeter. The resistivity of CdZnTe single crystal grown by the High Pressure Bridgman method is in the mid of $10^9$ ohm-cm. The detector structure is Au/CdZnTe/Au and gold electrode is formed by electroless deposition method. Resolutions of 4.8keV and 2.2keV were observed at 22.2keV line of $^{109}Cd$ and 59.6keV line of $^{241}Am$ at room temperature, respectively. We also constructed the small size pocket surveymeter using home made CdZnTe detector. It shows the good linearity over a range from 1mR/hr to 10R/hr with deviation less than 5%. The sensitivity of the surveymeter developed is $2.2{\times}10^3 cps/Rad\;hr^{-1}$ for the 662keV of $^{l37}Cs\;{\gamma}-ray$.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.3
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• pp.21-28
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• 2018

This paper presents two-step simulations to calculate the influence of blast-induced pressures on explosion-protection valves installed at the boundary between a protection facility and a tunnel entering the facility. The first step is to calculate the respective overpressure on the entrance and exit of the tunnel when an explosion occurs near the tunnel entrance and exit to approach the protection facility. Secondly, the blast pressures on the explosion-protection valves mounted to walls located near the tunnel inside approaching the protection facility are analyzed with a 0.1 ms time variation using the results obtained from the first-step calculations. The following conclusions could be derived as a results: (1) The analysis of the entrance tunnel scenario, P1, leads to the maximum overpressure of 47 kPa, approximately a half of the ambient pressure, at the inner entrance due to the effect of blast barrier. For the scenario, P2, the case not blocked by the barrier, the maximum overpressure is 628 kPa, which is relatively high, namely, 5.2 times the ambient pressure. (2) It is observed that the pressure for the entrance tunnel is effectively mitigated because the initial blast pressures are partially offset from each other according to the geometry of the entrance and a portion of the pressures is discharged to the outside.