• The Journal of Korean Academy of Prosthodontics
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• v.42 no.5
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• pp.489-500
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• 2004

Statement of problem: The use of zirconia prostheses fabricated with CAD/CAM system is on an increasing trend in dentistry. However, evaluation of the fit related to internal relief and marginal reproducibility of zirconia has not been reported. Purpose : This study was to evaluate the fit related to internal relief and marginal reproducibility of zirconia core fabricated with CAD/CAM system. Materials and methods: The evaluation was based on 30 zirconia cores and 5 IPS-Empress2 cores. Zirconia cores were fabricated in different conditions of internal relief(0, 10, 20, 30, 40 and $50{\mu}m$), and IPS-Empress2 cores were fabricated in accordance with the manufacturer's instructions. Before cementation, the marginal discrepancies or cores were measured on metal die. And then, each core was cemented to stone die, embedded in an acrylic resin and sectioned in two planes(mesiodistally and labiopalatally). The internal gaps were measured at the margin and axial surface. Measurements for the marginal discrepancies, the internal marginal gaps and the internal axial gaps were performed under a measuring microscope(Compact measuring microscope STM5; Olympus, Japan) at a magnification of ${\times}100$. In addition, the marginal conagurations of metal die, zirconia core and IPS-Empress2 core were examined with SEM(S-2700, Hitachi, Japan). Results : Within the limits of this study the results were as follows. 1. Compared with IPS-Empress2 cores, the marginal discrepancies of zirconia cores had no significant differences. the internal marginal gaps were statistically smaller and the internal axial gaps were statistically larger in each condition of internal relief. 2. The marginal discrepancies and the internal marginal gaps of zirconia cores had no significant differences related to the conditions of internal relief(P>0.05). 3. The internal axial gaps of zirconia cores with $0{\sim}20{\mu}$m for internal relief were significantly larger than that with $50{\mu}m$ (P<(0.0001). 4. SEM micrographs showed favorable marginal reproducibility of zirconia core and smooth texture on the milling surface. Conclusion: The marginal discrepancy and the internal gaps of zirconia core were clinically acceptable and the milling surface was showed smooth texture. For fabrication of the durable esthetic restoration, further investigations on complex design of core, milling accuracy, compatability of enamel porcelain and porcelain firing seems to be needed.

• Tuberculosis and Respiratory Diseases
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• v.81 no.3
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• pp.241-246
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• 2018

Background: The "Tuberculosis Relief Belt Supporting Project (Tuberculosis Patient Management Project for Poverty Groups)" is a national program for socioeconomically vulnerable tuberculosis (TB) patients. We sought to evaluate the clinical and socioeconomic characteristics of poverty-stricken TB patients, and determined the need for relief. Methods: We examined in-patients with TB, who were supported by this project at the National Medical Center from 2014 to 2015. We retrospectively investigated the patients' socioeconomic status, clinical characteristics, and project expenditures. Results: Fifty-eight patients were enrolled. Among 55 patients with known income status, 24 (43.6%) had no income. Most patients (80%) lived alone. A total of 48 patients (82.8%) had more than one underlying disease. More than half of the enrolled patients (30 patients, 51.7%) had smear-positive TB. Cavitary disease was found in 38 patients (65.5%). Among the 38 patients with known resistance status, 19 (50%) had drug-resistant TB. In terms of disease severity, 96.6% of the cases had moderate-to-severe disease. A total of 14 patients (26.4%) died during treatment. Nursing expenses were supported for 12 patients (20.7%), with patient transportation costs reimbursed for 35 patients (60%). In terms of treatment expenses for 31 people (53.4%), 93.5% of them were supported by uninsured benefits. Conclusion: Underlying disease, infectivity, drug resistance, severity, and death occurred frequently in socioeconomically vulnerable patients with TB. Many uninsured treatment costs were not supported by the current government TB programs, and the "Tuberculosis Relief Belt Supporting Project" compensated for these limitations.

• The Journal of Internal Korean Medicine
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• v.44 no.4
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• pp.675-702
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• 2023

Objective: This study assessed the effectiveness of using Yijung-tang to treat chronic gastritis through a systematic review and meta-analysis of randomized controlled trials (RCTs). Methods: The search was conducted using keywords such as "gastritis", "Lizhong", "Yijung", and "Chronic gastritis" on July 31, 2023. A meta-analysis was conducted according to outcome measurements, such as total effective rate (TER), Traditional chinese medicine symptom score (TSS), gastric hormones, and symptom relief time, using the Review Manager website. Results: A total of 11 RCT studies were selected. The treatment group (Yijung-tang-gagam or Yijung-tang-gagam+Western medicine) showed significant improvement effects in terms of TER, TSS, serum gastrointestinal hormones (motilin (MTL), gastrin (GAS), and somatostatin (SS)), and symptom relief time compared to the control group (Western medicine). TER-RR : 1.20, 95% CI : 1.11 to 1.30, P≤0.00001, RR : 1.21, 95% CI : 1.14 to 1.28, P≤0.00001; MTL-MD : 35.99, 95% CI : 30.79 to 41.20, P≤0.00001); GAS-MD : 103.33, 95% CI : 97.62 to 109.04, P≤0.00001); SS : MD : -37.19, 95% CI : -41.75 to -32.64, P≤0.00001; symptom relief time (nausea)-MD : -1.96, 95% CI : -2.47 to -1.45, P≤0.00001; symptom relief time (colic)-MD : -1.75, 95% CI : -2.31 to -1.18, P≤0.00001. Conclusion: This study suggests that Yijung-tang is effective against chronic gastritis. However, the number of studies was insufficient, and the diagnosis and evaluation criteria were not standardized. Furthermore, because of the low quality of the included studies, more clinical studies need to be conducted to increase the possibility of clinical use.

• International Journal of CAD/CAM
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• v.7 no.1
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• pp.31-40
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• 2007

Reverse engineering of reliefs aims to turn an existing relief superimposed on an underlying surface into a geometric model which may be applied to a different base surface. Steps in this process include segmenting the relief from the background, and describing it as an offset height field relative to the underlying surface. We have previously considered relief segmentation using a geometric snake. Here, we show how to use this initial segmentation to estimate the background surface lying under the relief, which can be used (i) to refine the segmentation and (ii) to express the relief as an offset field. Our approach fits a B-spline surface patch to the measured background data surrounding the relief, while tension terms ensure this background surface smoothly continues underneath the relief where there are no measured background data points to fit. After making an initial estimate of relief offset height everywhere within the patch, we use a support vector machine to refine the segmentation. Tests demonstrate that this approach can accurately model the background surface where it underlies the relief, providing more accurate segmentation, as well as relief height field estimation. In particular, this approach provides significant improvements for relief concavities with narrow mouths and can segment reliefs with small internal holes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1109-1112
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• 2004

This study reports on the pressure relief design and braided composite of surge arrester. Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. As a solution, this study describes pressure relief design performance of arresters with braided composite module. In general, braided composite has Potential for improved impact and delamination resistance. Manufacturing processes of the braided composite could also be automated and could potentially lead to lower costs. Therefore, in consideration of characteristics of pressure relief for polymer arrester, the fabric pattern of braided composite was decided. And Polymer arrester module was manufactured with braid. The mechanisms of pressure occurrence and relief were investigated basically by analyzing arc energy and the correlation between thermal shock and indoor pressure in pressure relief test.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.175-179
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• 2005

The main objective of this paper is to module design and pressure relief test a new type of polymer gapless surge arrester for power distribution line. Metal oxide surge arrester for most electric power system applications, power distribution line and electric train are now being used extensively to protect overvoltage due to lightning. Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. When breakdown of gapless elements in a surge arrester occurs due to flashover, fault short current flows through the arrester and internal pressure of the arrester rises. The pressure rise can usually be limited by fitting a pressure relief diaphragm and transferring the arc from the inside to the outside of the housing. However, there is possibility of porcelain fragmentation caused by the thermal shock, pressure rise, etc. Non-fragmenting of the housing is the most desired way to prevent damage to other equipment. The pressure change which is occurred by flashover become discharge energy. This discharge energy raises to damage arrester housing and arrester housing is dispersed as small fragment. Therefore, the pressure relief design is requested to obstruct housing dispersion.

• Journal of Drive and Control
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• v.13 no.4
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• pp.7-13
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• 2016

This paper presents the meter-out and meter-in speed control characteristics of a pneumatic cylinder with relief valve type cushion device. The piston displacement and velocity are measured to investigate high speed driving performance with variation of the pressure setting in relief valve, air supply pressure, load mass, the supply and exhaust flow rate from the cylinder. Also, the internal pressures and temperatures driving pressure and cushion chamber are measured. The piston displacements and velocities of meter-out and meter-in control are compared experimentally determined data. A comparison experimental data meter-out and meter-in control show that a relief valve type cushion device is suitable for high speed pneumatic cylinders. The desired response characteristics of piston displacement and velocity are satisfactory adjust the pressure setting of a relief valve with varying system parameters such as air supply pressure, load mass and controlled flow rate.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.133-140
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• 1999

It is possible for a volume of fluid to become trapped in the space between two adjoining teeth ad the tips of the teeth engage in Gear Pump with involute teeth. This trapped fluid leads to several harmful results, for example fluctuating pressure and aeration of pump. In this study, hence, theoretical and experimental analyses on this 'Trapping' were accomplished as using relief port(or escape port), one of the means for avoid it. Also, the grasp and analysis on variational type of the internal pressure in parallel with above experiments are achieved so that hydrodynamic behaviors in pump were contemplated.

• Tribology and Lubricants
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• v.16 no.2
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• pp.126-132
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• 2000

It is possible for a volume of fluid to become trapped in the space between two adjoining teeth as the tips of the teeth engage in Gear Pump with involute teeth. This trapped fluid leads to several harmful results, for example fluctuating pressure and aeration of pump. In this study, hence, theoretical and experimental analyses on this'Trapping'were accomplished as using relief port(or escape port), one of the means for avoid it. Also, the grasp and analysis on variational type of the internal pressure in parallel with above experiments are achieved so that hydrodynamic behaviors in pump were contemplated.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.11a
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• pp.114-120
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• 1999

It is possible for a volume of fluid to become trapped in the space between two adjoining teeth and the tips of the teeth engage in Gear Pumu with involute teeth. This trapped fluid leads to several harmful results, for example fluctuating pressure and aeration of pump. In this study, hence, theoretical and experimental analyses on this 'Trapping' were accomplished as using relief port, one of the means for avoiding it. Also, the grasp and analysis on variational type of the internal pressure in parallel with above experiments are achieved so that hydrodynamic behaviors in pump were contemplated.