• 제목/요약/키워드: Flow defect

검색결과 348건 처리시간 0.024초

CMP 패드 컨디셔닝 온도에 따른 산화막의 연마특성 (CMP Properties of Oxide Film with Various Pad Conditioning Temperatures)

  • 최권우;김남훈;서용진;이우선
    • 한국전기전자재료학회논문지
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    • 제18권4호
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    • pp.297-302
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    • 2005
  • Chemical mechanical polishing(CMP) performances can be optimized by several process parameters such as equipment and consumables (pad, backing film and slurry). Pad properties are important in determining removal rate and planarization ability of a CMP process. It is investigated the performance of oxide CMP process using commercial silica slurry after the pad conditioning temperature was varied. Conditioning process with the high temperature made the slurry be unrestricted to flow and be hold, which made the removal rate of oxide film increase. The pad became softer and flexible as the conditioning temperature increases. Then the softer pad provided the better surface planarity of oxide film without defect.

유한요소법을 이용한 disk-brake piston의 공정설계 (Application of FEM to the Forming Process of Disk-Brake Piston)

  • 황병복;이호용
    • 소성∙가공
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    • 제3권2호
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    • pp.178-188
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    • 1994
  • A design methodology is applied for manufacturing a disk-brake piston component. The design criteria are the limit drawing ratio and the forging load within the available press limit. Also, the final product should not have any geometrical defect. The rigid-plastic FEM has been applied to simulate the conventional four stage manufacturing processes, which include deep drawing and forging process. Simulation of one stage process from a selected stock to the final product shape is performed for generating information on additional requirements for metal flow. Two stage forming processes with different punch corner and nose geometries are also simulated to identify the possible best solutions. Finally, the best manufacturing process is selected, which is using a hemispherical punch int he deep drawing process.

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Red-shift of the photoluminescence peak of N-doped ZnO phosphors

  • Kim, Jun-Kwan;Lim, Jung-Wook;Kim, Hyun-Tak;Yun, Sun-Jin
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.895-897
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    • 2008
  • ZnO films were fabricated using rf-magnetron sputter deposition process with different $N_2$ ambient. N-content in N-doped ZnO films was less than 1%. The wavelength of the highest intensity PL peak of N-doped ZnO was shifted to higher wavelength with increasing $N_2$ flow rate in the deposition ambient. These results indicated that the optical property of ZnO was significantly affected by the defect level created by doping with a very small amount of N.

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히팅카고 응고사고 분석 - 나일브렌드를 중심으로 - (An Analyse for Solidified Accident of Nile Blend Crude Oil)

  • 김영모;이옥용
    • 해양환경안전학회지
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    • 제8권2호
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    • pp.79-86
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    • 2002
  • A heating cargo is solidified by several reasons during carriage. This study is to analyse a cargo accident which 811,202 US barrels of Nile Blend crude oil reamined solid In the tanks after discharge. There are some possibilities that low temperature of Beading cargo below cloud point and wax appearance temperature at loading time, heating interruption during voyage or discharging, and prohibition of crude oil washing during discharging might influence the cargo solidified. But we concluded that the defect of heating system would most affect the heating cargo solidified locally, and which blocked drain hole of bottom transverse and web frame and they obstruct flow of heating cargo in the tanks.

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적외선 열화상을 이용한 공동주택 단열성능 평가 - TDR(온도상대비)을 중심으로 - (Insulation Performance Evaluation of Apartment Housing Using Infra-red Camera)

  • 최보혜;최경석;강재식;이승언
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2009년도 하계학술발표대회 논문집
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    • pp.718-723
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    • 2009
  • The purpose of this study is to present an in-site evaluation method for building insulation performance using Infra-red camera. The research contents of this study are to evaluate validity and suitability of building insulation defect survey using Infra-red camera for apartment housing with temperature & heat flow pattern analyze method. By establishing the in-site evaluation method building insulation performance using infra-red camera, it is expected that 1) building envelope repair market will be activated by using developed method in ESCO and remodeling companies, 2) the method developed in this research will contribute to reduce national energy consumption by promoting old building insulation remodeling.

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흉부대동맥의 동맥류 절제 치험례 (Surgical Resection of the Aneurysm of the Thoracic Aorta: Report of A Case)

  • 김영태
    • Journal of Chest Surgery
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    • 제6권1호
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    • pp.51-56
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    • 1973
  • This is one case report of successful resection of the aneurysm of the thoracic aorta, which det-ected by thoractomy unexpectedly, in the Department of Thoracic Surgery, Hanyang University Hospital. The patient was a 34 years old woman and subjective complaints was not related with the aneurysm. Chest film showed a small round hazy shadow in the left margin of the upper posterior mediastinum. A saccular aneurysm located on the descending thoracic aorta, 7cm distal to the left subclavian artery and arouse from the antero-lateral wall of the aorta. Excision of the saccular aneurysm was performed by cross clamping the descending aorta above and below the aneurysm, and then the defect of the aortic wall was closed by aortorrhaphy with continuous suture. Crossclamping time was required 15 minute. Histopathologically, the wall of the aneurysm consisted of all layers of the arterial wall, that is, intima, media and adventitia. Postoperative course was uneventful and aortogram showed good continuity of the blood flow of the entire aorta.

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판재 인발 에서 내부결함 에 대한 변형경화 의 영향 에 관한 해석 (Analysis of the Effect of Strain Hardening on Central Bursting Defects in Strip Drawing)

  • 최재찬;김병민
    • 대한기계학회논문집
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    • 제9권5호
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    • pp.677-682
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    • 1985
  • 극치해석적인 상계정리를 기초로 하여, 평면변형 인발에서 발생하는 내부결함(central bursting)을 예측하기 위해 중심에서 공동(voids)을 가진 금속에 대해 비례흐름(proportional flow)과 내부결 함의 흐름을 비교하여 해석하였다. 이 결함을 촉진시키는 공정조건에 대한 판정식(criterion)을 변형경화 금속에 대해 유도하였다. 공동을 가진 금속은 공동들을 축소시키기 위해 정상적인 재 료(sound material)의 흐름과 동일 방법으로 흐를 수 있으며, 경우에 따라서는 내부결함을 확장 하기 위해 흐를 수도 있다. 본 연구에서는 다이의 경사각, 단면감소율 및 마찰 등의 어떤 공정 변수 영역에서 중심축 상에 많은 공동을 가진 변형경화 금속에서도 내부결함이 발생할 수 있다는 것이다.

부가가치와 경제적부가가치를 결합한 경영성과평가에 관한 실증적 연구 (Study on the Business Performance Evaluation with VA and EVA)

  • 김태성;구일섭;임익성
    • 품질경영학회지
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    • 제29권4호
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    • pp.153-160
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    • 2001
  • The proposed system measures business performance by considering both VA(Value-Added), which represents stakeholder's point of view and EVA(Economic Value-Added), which represents shareholder's point of view. To do so, we suggest a business performance scheme which utilizes VA per Capita (Value- Added/Workers) and EVA to Invested Capital(Economic Value-Added /Invested Capital). For effective measurement of business performance, we consider simultaneously not only quantitative financial factors such as VA, EVA and cash flow but also qualitative value drivers such as defect ratio, inventory level, customer satisfaction, enterprise culture and so on. However, we don't consider the qualitative factors due to the limited data. To demonstrate the performance of the system, we conducted a case study using financial data of Korean automobile industry over 16 years from 1981 to 1996, which is taken from database of KISFAS (Korea Investors Services Financial Analysis System).

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신속한 주물 시제품 개발을 위한 전산모사 기술과 산업용 단층촬영기 및 쾌속표형기의 적용 (The Application of Computer Simulation, Industrial CT and DLS RP for the rapid development of casting pilot models)

  • 유승목;임채호;조인성;최정길
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2006년도 춘계학술대회 논문집
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    • pp.195-196
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    • 2006
  • Direct laser sintering (DLS) technology for the resign coated sand is one of attractive technologies to produce molds and cores for the foundry industry rapidly and cost effectively. The objective of this case study is to develop casting pilot models using computer simulation technology, DLS RP machine and industrial computed tomography. The proposed casting design was verified by the Z-Cast software in the fields of fluid flow and solidification during the casting process. Casting parts with aluminum alloy using the post-curing treated sand moulds and cores are accurate to dimension and defect free.

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Scimitar 증후군의 외과적 치험 (Intracardiac Repair of Scimitar Syndrome)

  • 허진;장봉현;이종태;김규태
    • Journal of Chest Surgery
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    • 제25권12호
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    • pp.1476-1481
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    • 1992
  • This presents a case of anomalous pulmonary venous drainage from the right lung to the inferior vena cava [scimitar syndrome], which was corrected with an intracardiac approach. Autogenous pericardium was used to create an intracardiac tunnel redirecting flow from the anomalous vein to the left atrium through a surgically enlarged atrial septal defect. The postoperative results have veen satisfactory.

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