• 제목/요약/키워드: Defect

검색결과 8,082건 처리시간 0.034초

Effects of Suspension Composition on Defects in Aqueous Tape Casting of Alumina Ceramics: A Rheological Study

  • Shin, Hyo-Soon
    • 한국세라믹학회지
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    • 제42권1호
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    • pp.1-6
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    • 2005
  • In aqueous alumina tape casting, the effects of altering the composition of the suspensions, the binders and the casting thickness were studied. The rheological behavior of the suspensions and the defects of the dried tapes were examined and the relationships between them are discussed. The changes in the defect regions reported in the previous paper were related with the rheological properties with variations of the binder, the composition and the casting thickness. The shear thinning factor increased with the organic content and the solid content (the decrease of water content). The apparent viscosity increased with the shear thinning factor. The relation between the shear thinning factor and the log apparent viscosity was similar for all binder types. In the relation between the defect free region and the rheological properties, the defect free region became narrower with increasing casting thickness. The defect free region is independent of binder type. Therefore, the thicker tape is more difficult to produce in aqueous alumina tape casting. Knowledge of the rheological properties of the suspensions could help Predict the defect type and the possibility of defect free dried tapes.

조기학습정지를 이용한 원전 SG세관 결함크기 예측 신경회로망의 성능 향상 (A performance improvement of neural network for predicting defect size of steam generator tube using early stopping)

  • 조남훈
    • 전기학회논문지
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    • 제57권11호
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    • pp.2095-2101
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    • 2008
  • In this paper, we consider a performance improvement of neural network for predicting defect size of steam generator tube using early stopping. Usually, neural network is trained until MSE becomes less than a prescribed error goal. The smaller the error goal, the greater the prediction performance for the trained data. However, as the error goal is decreased, an over fitting is likely to start during supervised training of a neural network, which usually deteriorates the generalization performance. We propose that, for the prediction of an axisymmetric defect size, early stopping can be used to avoid the over-fitting. Through various experiments on the axisymmetric defect samples, we found that the difference bet ween the prediction error of neural network based on early stopping and that of ideal neural network is reasonably small. This indicates that the error goal used for neural network training for the prediction of defect size can be efficiently selected by early stopping.

선천성 좌측 심낭결손증 [1례 보고] (Congenital Left Pericardial Defect: A Case Report)

  • 성시찬
    • Journal of Chest Surgery
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    • 제15권1호
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    • pp.129-135
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    • 1982
  • Congenital pericardial defect is a rare anomaly, which was first described by M. Columbus in 1559. Four hundred years later the first clinical diagnosis was reported by Ellis et al. The congenital pericardial defect Is usually asymptomatic and Is found Incidentally at thoracotomy and autopsy, but it appears that partial absence of pericardium Is not Innocuous because of sudden death due to herniation of a portion of heart. We experienced congenital left pericardial defect in 20 year old female who was diagnosed as left ventricular aneurysm before operation. This patient complained of dyspnea on exertion and anterior chest discomfortness. Physical examination revealed Grade II pansystolic murmur on the 3rd and 4th intercostal space left sternal border. There were specific abnormal findings on the chest plain film, EKG, ultrasonography, and left ventriculography. On 9th July 1981, an operation was performed and found the left partial pericardial defect through which a large portion of left ventricle was herniated Into left pleural space. The method of operation was removal of adhesion and widening of the pericardial defect to avoid Incarceration. After operation, we observed marked Improvement of symptoms and disappearance of cardiac murmur.

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Determination of Alpha Defect Center in the Nature Using EPR Spectroscopy

  • Cho, Young-Hwan;Hyun, Sung-Pil;Pilsoo Hahn
    • 한국자기공명학회논문지
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    • 제5권1호
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    • pp.13-18
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    • 2001
  • Natural alpha radiation produced a stable defect center to certain minerals. Electron Paramagnetic Resonance(EPR) spectroscopy is a powerful tool f3r quantifying this defect center. EPR method has been applied to trace alpha-radiation effect around the uranium ore deposit. The results show that EPR technique can be used to measure rapidly and nondestructively the defect center produced by natural alpha radiation. In general, a good correlation was achieved between defect center concentration and actinide elements(U, Th). These results imply that the concentration of defect center is dependent on the alpha radiation dose over long time scale.

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조경시설공사의 시공품질 분석을 통한 품질관리항목의 중요도 연구 (A Study on the Relative Importance of Quality Management Items through the Defect Analysis in the Landscape Construction Process)

  • 이상석;최기수
    • 한국조경학회지
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    • 제25권3호
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    • pp.1-11
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    • 1997
  • This study aims to estimate the relative importance of quality management items through the defect analysis in the landscape construction process. The RIQMI are decided by the defect coefficient and it's cause weight. The defect items in the landscape construction process were classified by 56 items based on the classification form of '96 landscape architectural construction standard and the cause pattern were categorized 4 types as design, material, construction, and environment factors. To analyze the defect coefficient and the aucse weight by defect, the researcher surveyed the questionnaires on the 103 engineers and the 31 experts on the landscape architectural construction. The result of this study are as follows. The relative importance by facilities pattern turn out to be much higher construction, material fator than design. environment factor in wood facilities, paving facilities, and steel facilities, the RIQMI is very high in timber crack, timber vending, faulty of timber against decay, welding faulty of steel facilities in material factor, and timber crack, faulty of timber against decay, finish faulty of steel facilities, welding faulty of steel facilities in construction factor.

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심폐기를 이용한 심방중격결손의 외과적 교정: 1례 보고 (Surgical Repair of Atrial Septal Defect Using Extracorporeal Circulation: One Case Report)

  • 이동준
    • Journal of Chest Surgery
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    • 제10권1호
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    • pp.143-147
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    • 1977
  • Atrial septal defect is the most common of the congenital heart disease in the adult. Since the first description of atrial septal defect by Rokitansky in 1857, this anomaly has been studied by many workers in past one century. In 1953, Lewis had first corrected the atrial septal defect under direct vision with deep hypothermia, and Gibbon [1954] had first done the atrial septal defect under direct vision with extracorporeal circulation. In our college [May 2’ 1977], we have first repaired the A.S.D. under direct vision with artificial heart-lung machine and, the defect was 4x5cm in size which was closed by Dacron patch. This patient was 12 year old girl who is well now. [postoperative 13 days]

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An analysis of the utilization of defect deposits for apartment complexes

  • Seo, Deok-Seok;Lee, Ung-Kyun
    • 한국건축시공학회지
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    • 제13권6호
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    • pp.549-556
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    • 2013
  • This study analyzed the actual use of defect deposits for financing long-term expenses (that is, expenses incurred within 4-10 years of building completion) and for financing short-term expenses (that is, expenses incurred within 3 years of building completion). Therefore, 36 cost data on the expenses financed out of defect deposits for apartment complexes were collected from construction companies and analyzed using statistical methods. The findings revealed that 62.6 percent of defect deposits were spent to resolve actual defects, and 37.4 percent were spent resolving resident complaints. Furthermore, these results are valid regardless of the location of the complexes. As such, these results could be of significance when establishing or revising regulations regarding the repair of the long-term defects of apartment complexes.

내부 감육 배관의 손상압력 평가 모델 개발 (Development of Failure Pressure Evaluation Model for Internally Well Thinned Piping Components)

  • 나만균;박치용;김진원
    • 대한기계학회논문집A
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    • 제29권7호
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    • pp.947-954
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    • 2005
  • The purpose of this study is to develop failure pressure evaluation models, which are applicable to straight pipes and elbows containing an internally wall thinning defect induced by flow-accelerated-corrosion (FAC). In this study, thus, three dimensional finite element (FE) analyses are performed to investigate the dependences of failure pressure of internally wall thinned pipe on the defect shape, the pipe geometry, and the defect location and bend radius of elbow. Also, the existing failure pressure assessment models for externally wall thinned pipes are examined. Based on these, the new models for assessing failure pressure of piping components with an internally wall thinning defect are proposed. Comparison of failure pressure, predicted by proposed models, with FE analysis result shows good agreement regardless of pipe type, defect shape, and defect location and bend radius.

공동주택관리법 하자담보책임 종료 확인 절차의 문제점 및 개선방안 (On the problem and improvements about 'End of Confirmation for Defect Liliability' on the Management of Apartment Houses Decree)

  • 김진국;방홍순;김옥규
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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    • pp.274-275
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    • 2017
  • Decree on the Management of Apartment Houses. Article 36 (Liability for warranty Repair Defects), Article 37 (About Repair Defect, etc), and its implementing ordinances, Article 36 (Term of warranty liability) Article 37 (Defect criteria), Article 38 (procedure of Repair defect), Article 39 (type of warranty liability), Enforcement Rule Article 17 (Certifiation of warranty liability). On the basis of the upper Decree, In spite of Standard and forms of 'Completion of Repair Defect' was exist, it was hard to receive 'End of Confirmation' in practice. The purpose of this study is to propose basics in order that Practitioners can apply problems and improvements about Decree on the Management of Apartment Houses.

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공동주택 층간 이음부 균열 보수공법에 대한 하자분쟁 분석 (An Analysis of Defect Dispute about Inter-Layer Crack Repair Method on Apartment Houses)

  • 이태형;정용기;최병주;김옥규
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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    • pp.146-147
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    • 2017
  • Recently, as the living standards of residents in apartment houses continued to improve, the dispute of post management have also increased. one of the Issue, Concrete Cracks comprised high percentage of dispute. Especially, between criteria the cost of repairing defect and the judgement of defect isn't clear, they are a lot of dispute in this regard. Even though lots of the criteria about Inter-layer crack is existed by judging defects, In a court, they are judging their own criteria about Inter-layer crack. The purpose of this study is to compare and analyze Defect Judement Standard both MOLIT and Court, and to provide the Improvement for Defect Judgement and Repair Method of Inter-layer concrete crack.

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