• Title/Summary/Keyword: Internal relief

검색결과 149건 처리시간 0.024초

CAD/CAM system으로 제작한 zirconia core의 적합도 (THE FIT OF ZIRCONIA FORE FABRICATED WITH CAD/CAM SYSTEM)

  • 성지윤;전영찬;정창모;임장섭
    • 대한치과보철학회지
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    • 제42권5호
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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 Relief Belt Supporting Project (Tuberculosis Patient Management Project for Poverty Group)

  • Kim, Jae Kyoung;Jeong, Ina;Lee, Ji Yeon;Kim, Jung Hyun;Han, Ah Yeon;Kim, So Yeon;Joh, Joon Sung
    • Tuberculosis and Respiratory Diseases
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    • 제81권3호
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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.

만성 위염에 대한 이중탕(理中湯)의 효과 : 체계적 문헌 고찰 및 메타 분석 (The Effect of Yijung-tang for Chronic Gastritis: A Systemic Review and Meta-Analysis)

  • 김예슬;이영서;김경민;진명호
    • 대한한방내과학회지
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    • 제44권4호
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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.

Background Surface Estimation for Reverse Engineering of Reliefs

  • Liu, Shenglan;Martin, Ralph R.;Langbein, Frank C.;Rosin, Paul L.
    • International Journal of CAD/CAM
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    • 제7권1호
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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.

폴리머 피뢰기의 방압구조 및 특성 (Characteristics of polymer arrester with pressure relief structure)

  • 한동희;조한구;한세원
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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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.

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배전선로용 폴리머 피뢰기의 모듈 설계/제조 및 성능 (Relief Performance of Fault Current and Design/Manufacturing of Polymer Arresters for Power Distribution)

  • 조한구;윤한수;장태봉;최인혁
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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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.

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릴리프밸브 쿠션기구 내장형 공기압 실린더의 구동 특성 (Driving Characteristics of Pneumatic Cylinder with Relief Valve Cushion Devices)

  • 김도태
    • 드라이브 ㆍ 컨트롤
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    • 제13권4호
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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.

유압 기어펌프의 폐입현상과 릴리프 홈의 위치에 관한 연구 (A Study on the Trapping Phenomenon and Relief Port Position of Oil Hydraulic Gear Pump)

  • 김철호;노춘경;정재연
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1999년도 제29회 춘계학술대회
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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.

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Involute 치형을 가진 유압 기어펌프의 릴리프 홈의 위치에 관한 연구 (A Study on the Relief Port Position of Oil Hydraulic Gear Pump with Involute Teeth)

  • 김철호;정재연
    • Tribology and Lubricants
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    • 제16권2호
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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.

유압 기어펌프의 릴리프 홈 형상 변화에 따른 성능특성에 관한 연구 (A Study on the Performance Characteristics for Relief Port Shape of Oil Hydraulic Gear Pump)

  • 김철호;노춘경;정재연
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1999년도 제30회 추계학술대회
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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.

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