• 제목/요약/키워드: before-after evaluation

검색결과 2,126건 처리시간 0.043초

인장 굽힘피로를 받는 부재의 피로수명과 균열관통 (Fatigue Life and Peneration Behaviour of Material under Combined Tension and Bending Stress)

  • 남기우
    • 한국해양공학회지
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    • 제8권1호
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    • pp.41-49
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    • 1994
  • The leak-before-break(LBB) design on the large structures such as ship's hull, tank structure, pressure vessels etc. is one of the most inportant subjects for the evaluation and the assurance of safety. In these structures, various loads are acting. In some structural members, therefore, out-of-plane stress due to bending often may become with in-plane stress due to stretching. In the present report, the characteristics of fatigue life and peneration behaviour from a surface cracked plate under combined tension and bending have been studied experimentally and analytically by using eccentricity. Estimation of fatigue crack growth was done with the Newman-Raju formula before penetration, and with the stress intensity factor after penetration proposed by the author. Calculated aspect ratio showed the good agreement with the experimental result. It was also found that particular crack growth behaviour and crack shape after penetration can be satisfactorily evaluated using the K solution proposed.

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단순 외상팀 활성화 조건이 중증 외상 환자의 치료 결과에 미치는 영향 (Effectiveness of Simple Trauma Team Activation Criteria on Prognosis of Severe Trauma Patients)

  • 이동건;이강현;차경철;박경혜;최한주;김현;황성오
    • Journal of Trauma and Injury
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    • 제22권1호
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    • pp.71-76
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    • 2009
  • Purpose: The goal of this study was to compare the outcome of the after trauma team (AfterTT) group to the before trauma team (BeforeTT) group. Methods: All trauma patients who visited to emergency room (ER) between July 1, 2006 and February 29,2008 based on trauma registry, with systolic blood pressure (SBP) < 90 mmHg or GCS < 9 were included in this study. We compared the amount of packed RBC transfusion, the ER stay time, the ER visit to CT evaluation time, the ER visit to operation time, the length of ICU stay, the length of hospital admission and the survival discharge rate between the AfterTT group and the BeforeTT group. Patients with brain injuries had little chance of survival. Burn patients, who visited the ER 24 hours after injury and patients who were dead on arrival (DOA) were excluded from this study. Results: Total of 93 patients were included in this study: 42 in the AfterTT group and 51 in the BeforeTT group. The AfterTT group and the Before TT group showed no differences in Revised Trauma Score (RTS) and mean age. The amount of packed RBC transfusion was lower in the AfterTT group, but no statistically significant difference was noted (AfterTT 11${\pm}$11units, BeforeTT 16${\pm}$15units, p=0.136). The ER visit to operation time was shorter in the AfterTT group, but there were no statistically significant difference between the groups (AfterTT 251${\pm}$223 minutes, BeforeTT 486${\pm}$460 minutes, p=0.082). The length of ICU stay was shorter in the AfterTT group, but the difference was not statistically significant (AfterTT 11${\pm}$12 days, Before TT 15${\pm}$30 days, p=0.438). The length of Hospital admission was shorter in the AfterTT group (AfterTT 43${\pm}$37 days, BeforeTT 68${\pm}$70 days, p=0.032), but this difference was not statistically significant. Conclusion: Simple Trauma team activation criteria decreased the amount of packed RBC transfusion and the hospital admission duration. Hemodynamic instability (SBP < 90 mmHg) and decreased mental state (GCS<9) are good indices for activating the trauma team.

초등학교 일반교실의 색채 환경 평가에 관한 비교연구 - 제7차 교육과정 전.후의 광주광역시내 초등학교를 중심으로 - (Comparative Study on Color of Environment Evaluation of General Classrooms at Elementary Schools - With elementary schools in Gwang-ju Metropolitan City Since the 7th Curriculum -)

  • 노영진;박성진;이청웅
    • 한국실내디자인학회논문집
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    • 제16권5호
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    • pp.89-97
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    • 2007
  • This study compares, analyzes and reevaluates color conditions and images before and after the execution of the 7th curriculum with elementary schools in Gwang-ju Metropolitan City based on the fact that color among physical environments of elementary classrooms has an important influence on children's emotion and draws problems and aims to accumulate the basic materials for preparing guidelines of improving color environment at general classrooms of elementary schools. Consequently, according to color conditions, major colors on ceiling and wall were high brightness/nigh chroma of Y and YR line regardless of division of grades and other color factors of classroom showed that wall and ceiling used similar colors, but brightness was higher after change than before it. In evaluation of color images, lower grades showed negative color images such as 'common,' 'rustic,' and 'strange' before change, but they showed positive color images after change such as 'clean,' 'unique,' and 'soft'. But, most of higher grades showed negative reactions before change such as 'common,' 'strange,' and 'rustic' and they showed positive reactions after change only in such items as 'clean,' 'warm,' and 'unique', but Indicated negative reactions in remaining items such as 'strange,' 'rustic,' 'stiff,' and 'artificial'. Accordingly, in using colors for lower grade classroom, arrangement of colors through adjustment of brightness and chroma between ceiling, wall and other components based on coloring of high brightness and low chroma of similar colors should be considered and for higher grade classroom, arrangement of colors of unique images of mid-brightness/mid-chroma among warm color lines of similar colors should be examined.

세계측지계 변환에 따른 변환 전후의 타원체 적합성 비교분석 (Analyses of ellipsoid agreement before and after change due to the introduction of global geodetic reference system)

  • 이석배
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 추계학술발표회 논문집
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    • pp.3-7
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    • 2004
  • Many countries have changed her geodetic reference system from local system to global system because of the global network's necessity. And, also Korean geodetic reference system changed from Tokyo datum to Global geodetic reference system since 2003 as the revision of Survey Law and Korean reference ellipsoid changed from Bessel 1841 ellipsoid to GRS80. The purpose of this paper is evaluation of ellipsoid agreement before and after change due to the introduction of global geodetic reference system in Korea. For the evaluation ellipsoid agreement was analyzed using two Korean geoid model -KOGD2003 and KOBGDM33- on both ellipsoid and area variation caused by change of reference ellipsoid was calculated.

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폴리아크릴 레진 누수보수재의 선정평가 후 현장 적용에 따른 효과 분석 (Effect of Evaluation before Site Application of Poly-acrylic Resin Leakage Repair Materials)

  • 조일규;안기원;송제영;오상근
    • 대한건축학회연합논문집
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    • 제20권6호
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    • pp.55-61
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    • 2018
  • This study improved the water repair materials of the polyacrylic system applied to concrete structures by controlling expansion, strengthening water resistance, and improving cohesiveness. The improved polyacrylate repair materials were evaluated against the existing products to verify their performance and level of improvement, and applied on-site to the concrete structures that are leaking the improved water. The verification method measured the presence of water leaks and the moisture content of concrete inside. Moisture levels were measured for two months before and after material installation, and at least 0.8 - 1.7% of humidity was reduced after installing polyacrylic resin, and no leakage was found.

APEX FINDER A.F.A.의 정확성에 관한 연구 (EVALUATION OF THE ACCURACY OF THE APEX FINDER A.F.A.)

  • 양미영;유현미;오태석
    • Restorative Dentistry and Endodontics
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    • 제23권2호
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    • pp.670-675
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    • 1998
  • Recently electronic apex locators have been used widely in root canal treatment, but, accuracy of electronic apex locators is controversial. The purpose of this study was to evaluate the accuracy of Apex Finder A.F.A(EIE Analytic Technology, U.S.A.) in vivo compared with Root-Zx and radiograph. The root canal lengths were determined with Root-Zx(32 tooth) in before pulp extirpation and after pulp extirpation. Then the radiographs were taken with a file in the canal. The root canal lengths were determined with Apex Finder A.F.A.(21 tooth) in before pulp extirpation and after pulp extirpation and under NaOCl. Then the radiographs were taken with a file in the canal. The results were as follows: 1. There was no significant statistical difference in Root-Zx between before pulp extirpation and after pulp extirpation(p > 0.05). 2. There was no significant statistical difference in Apex Finder A.F.A. between before pulp extirpation and after pulp extirpation(p > 0.05). But, there was significant statistical difference under NaOCl(p < 0.05). 3. There was no significant statistical difference in accuracy between Root-Zx and Apex Finder A.F.A.

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성대구증 환자의 공기역학적 검사 방법에 따른 치료 전과 후의 평균호기류율 비교 (Comparison of mean airflow rate before and after treatment in patients with sulcus vocalis according to aerodynamic analysis methods)

  • 이승연;최홍식;김재옥
    • 말소리와 음성과학
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    • 제15권4호
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    • pp.61-69
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    • 2023
  • 성대구증은 불완전 성대폐쇄부전으로 평균호기류율(mean airflow rate, MFR)이 높은 것이 특징이다. MFR은 phonatory aerodynamic system(PAS)의 두 공기역학적 검사 방법(MXPH, VOEF)으로 측정하며, 두 검사 방법에 따라 결과가 다르게 나타날 수 있다. 본 연구는 성대구증 환자 30명을 대상으로 PAS의 MXPH, VOEF 프로토콜에 따른 MFR의 치료 전과 후 차이, 치료 전후 변화량 간의 차이가 있는지 비교하였다. 그리고 치료 전과 후의 Voice handicap index(VHI), GRBS 및 기본주파수(F0)를 비교하였다. 연구결과, 성대구증 환자의 치료 전과 후 모두에서 검사 방법 간에 유의한 차이가 나타났으나 치료 전후의 변화량은 유의한 차이가 없었다. VHI와 GRBS는 치료 전에 비해 치료 후에 유의하게 감소하였으나 F0는 치료 전과 후에 유의한 차이가 없었다. 본 연구를 통해 성대구증 환자의 치료에 따른 MFR 변화를 평가할 때, 두 공기역학적 검사 방법(MXPH, VOEF) 중 어떠한 검사 방법을 사용해도 된다는 것을 알 수 있다.

Clinical Significance of Joint Detection of Serum VEGF, SIL-2R and HGF in Patients with Primary Hepatocellular Carcinoma before and after Percutaneous Microwave Coagulation Therapy

  • Chen, Ji-Dong;Xiong, Yan-Qun;Dong, Ke;Luo, Jun;Yue, Lin-Xian;Chen, Qin
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권11호
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    • pp.4545-4548
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    • 2014
  • Objective: To investigate the changes of serum vascular endothelial growth factor (VEGF), soluble interleukin-2 receptor (SIL-2R) and hepatocyte growth factor (HGF) contents in patients with primary hepatocellular carcinoma (HCC) before and after percutaneous microwave coagulation therapy (PMCT) and determine their clinical significance. Materials and Methods: Fasting venous blood (3 mL) from 81 patients with primary HCC diagnosed by pathology was collected in the mornings 1 day before PMCT, and 1 day, 7 days and 1 month after PMCT, and then the serum was separated and stored in $-70^{\circ}C$. The contents of VEGF, SIL-2R and HGF were detected by enzyme linked immunosorbent assay (ELISA). Results: The serum VEGF, SIL-2R and HGF contents in 81 patients with primary HCC had obviously dynamic changes before and after PMCT. By comparison to 1 day after PMCT with pre-operation, there was no statistical significance regarding VEGF and SIL-2R contents (P>0.05), but HGF content showed significant difference (P<0.01). Compared with pre-operation, VEGF, SIL-2R and HGF contents 7 days and 1 month after PMCT all manifested significant differences (P<0.01). By comparison to 7 days with 1 month after PMCT, there was no statistical significance regarding the VEGF content (P>0.05), whereas SIL-2R and HGF contents showed significant change (P<0.01). Conclusions: The contents of serum VEGF, SIL-2R and HGF have obviously dynamic changes in primary HCC before and after PMCT, and their joint detection is expected to be an effective hematologic evaluation index of PMCT for primary HCC.

후면 덧쌓기에 따른 농업용 저수지 제체의 안정성 평가 (Safety evaluation of agricultural reservoir embankment according to backside extension)

  • 이달원;노재진
    • 농업과학연구
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    • 제39권1호
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    • pp.97-110
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    • 2012
  • This study was carried out for safety evaluation, the practical application and improvement of design method of the agricultural reservoir embankment according to backside extension. Seepage analysis, slope stability analysis and finite element analysis were performed for steady state and transient conditions. Also, the pore water pressure, seepage quantity, safety factor and stress-strain behavior according to high water level and rapid drawdown were compared and analyzed. The pore water pressure at contact region between backside extension and old embankment was kept high after rapid drawdown. Therefore, backside extension is recommended that design method is required to be improved and reinforced more than the others raising embankment. The hydraulic gradients before and after backside extension showed high value at the base of the core, but they showed stable state at the upstream slope and downstream slope. The seepage quantity per 1 day and the leakage per 100 m for the steady state and transient conditions appeared to be safe against the piping. The safety factor of slope stability showed high at the steady state, and transient conditions did not show differences depending on the rapid drawdown. The safety factor was appeared high at the upstream slope before backside extension and downstream slope after extension. The excess pore water pressure for steady state and transient conditions showed negative(-) at the upstream slope, it was small at the downstream slope. The mean effective stress (p') showed high at the base of the core and to be wild distribution after the extension. The displacement after extension showed 0.02-0.06 m in the upstream slope, the maximum shear strain after extension was smaller than that before extension.

EIS를 이용한 염화물 및 방청제가 첨가된 콘크리트에 매립된 철근의 방식성능 평가에 관한 실험적 연구 (A Experimental Study on the Evaluation of Anti-corrosion Performance of rebar in concrete added chloride and inhibitor using EIS method)

  • 박장현;이한승
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
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    • pp.134-135
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    • 2016
  • To evaluate anti-corrosion performance of rebar in concrete according to the amount of chloride and inhibitor, electrochemical impedance spectroscopy(EIS) method was conducted in this study. For the anti-corrosion performance evaluation according to time, Impedance of rebar in concrete was measured before and after 5 cycle of corrosion acceleration. As a results, The impedance of rebar in concrete added chloride decreased than before corrosion acceleration. However impedance of other specimens was maintained or increased than before corrosion acceleration.

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