• 제목/요약/키워드: ODS

검색결과 448건 처리시간 0.024초

모바일 RFID 환경에서 개선된 ODS 검색 서비스 (New ODS Retrieval Service in the Mobile RFID Environment)

  • 오정진;고형대;최한석
    • 한국콘텐츠학회논문지
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    • 제8권12호
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    • pp.45-52
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    • 2008
  • 모바일 RFID 환경에서의 객체 디렉토리 서비스(Object Directory Service: ODS)는 사물과 사물간의 통신 및 정보검색을 위해 반드시 필요한 핵심 인프라 요소 기술로서, 사물의 객체 정보가 있는 서버의 위치를 모바일 RFID 태그를 통해 실시간으로 인식하여 검색하는 서비스이다. 현재 ODS 검색 서비스는 글로벌한 모바일 RFID 환경에 적합하지만, 지역적인 로컬 네트워크 및 정보보안이 필요한 사설 네트워크에서는 불필요한 검색시간이 요구되고 효율성이 떨어지는 서비스 시스템이다. 따라서 본 논문에서는 기존의 ODS 검색 서비스 알고리즘을 개선하여 새롭게 로컬 환경에 적합한 ODS 검색 서비스 알고리즘을 제안하고, 개선된 ODS 검색 서비스 시스템의 성능평가 결과를 제시한다.

MA 316L ODS 및 Wet 316L ODS 스테인리스강에서 충격에너지에 미치는 소결 공정의 영향 (Effects of the Sintering Variable on Impact Energy in MA 316L ODS and Wet 316L ODS Stainless Steels)

  • 김성수;한창희;장진성
    • 한국분말재료학회지
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    • 제17권2호
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    • pp.113-122
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    • 2010
  • Two kinds of oxide-dispersion-strengthened (ODS) 316L stainless steel were manufactured using a wet mixing process(wet) and a mechanical alloying method (MA). An MA 316L ODS was prepared by a mixing of metal powder and a mechanical alloying process. A wet 316L ODS was manufactured by a wet mixing with 316L stainless steel powder. A solution of yttrium nitrate was dried after being in the wet 316L ODS alloy. The results showed that carbon and oxygen were effectively reduced during the degassing process before the hydroisostatic process (HIP) in both alloys. It appeared that the effect of HIP treatment on increase in impact energy was pronounced in the MA 316L ODS alloy. The MA 316L ODS alloy showed a higher yield strength and a smaller elongation, when compared to the wet 316L ODS alloy. This seemed to be attributed to the enhancement of bonding between oxide and matrix particles from HIP and to the presence of a finer oxide of about 20 nm from the MA process in the MA 316L ODS alloy.

실시간 데이터 접근을 위한 ODS 레이어 아키텍처 (An ODS Layered Architecture for Real-time Data Access)

  • 엄충용;정현석
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2005년도 춘계학술발표대회
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    • pp.599-602
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    • 2005
  • 본 논문에서는 운영 레거시 시스템으로부터 엔드 유저에까지 실시간으로 데이터를 전달하는 전체적인 프로세스를 정의한 ODS 레이어를 제시한다. ODS 의 레이어를 위하여 먼저 데이터 소스가 정의된다. 그 다음 데이터 소스로부터 ODS까지 데이터를 수집하는 방법이 정의된다. 마지막으로 엔드 유저 집단을 위한 ODS로의 데이터 접근을 준비한다. 운영 시스템과 ODS 간의 통합 레벨에 따른 ODS의 타입을 분류하고 특성을 요약한다.

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효율적인 로컬 모바일 RFID 시스템을 위한 ODS 검색 서비스 성능개선 (Object Directory Service)

  • 최성민;오정진;최한석
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2008년도 추계학술발표대회
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    • pp.1031-1034
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    • 2008
  • 현재 ODS(Object Directory Service) 검색 서비스는 글로벌한 모바일 RFID 환경에 적합하지만, 지역적인 로컬 네트워크 및 정보보안이 필요한 사설 네트워크에서는 불필요한 검색시간이 요구되고 효율성이 떨어지는 서비스 시스템이다. 따라서 본 논문에서는 기존의 ODS 검색 서비스 알고리즘을 개선하여 새롭게 로컬 환경에 적합한 ODS 검색 서비스 알고리즘을 제안하고, 개선된 ODS 검색 서비스 시스템의 성능평가 결과를 제시한다..

MICROSTRUCTURES AND MECHANICAL PROPERTIES OF ODS FERRITIC STAINLESS STEELS FOR HIGH TEMPERATURE SERVICE APPLICATIONS

  • SANGHOON NOH;SUK HOON KANG;TAE KYU KIM
    • Archives of Metallurgy and Materials
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    • 제64권3호
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    • pp.921-924
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    • 2019
  • In this study, ODS ferritic stainless steels were fabricated using a commercial alloy powder, and their microstructures and mechanical properties were studied to develop the advanced structural materials for high temperature service applications. Mechanical alloying and uniaxial hot pressing processes were employed to produce the ODS ferritic stainless steels. It was revealed that oxide particles in the ODS stainless steels were composed of Y-Si-O, Y-Ti-Si-O, and Y-Hf-Si-O complex oxides were observed depending on minor alloying elements, Ti and Hf. The ODS ferritic stainless steel with a Hf addition presented ultra-fine grains with uniform distributions of fine complex oxide particles which located in grains and on the grain boundaries. These favorable microstructures led to superior tensile properties than commercial stainless steel and ODS ferritic steel with Ti addition at elevated temperature.

산화물 분산 강화 강 분말이 첨가된 자동차 부품용 철계 복합 소재의 미세조직 및 마모 특성 (Microstructure and Wear Properties of Oxide Dispersion Strengthened Steel Powder Added Steel-Based Composite Material for Automotive Part)

  • 김영균;박종관;이기안
    • 한국분말재료학회지
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    • 제25권1호
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    • pp.36-42
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    • 2018
  • In order to expand the application of oxide dispersion-strengthened (ODS) steel, a composite material is manufactured by adding mechanically alloyed ODS steel powder to conventional steel and investigated in terms of microstructure and wear properties. For comparison, a commercial automobile part material is also tested. Initial microstructural observations confirm that the composite material with added ODS steel contains i) a pearlitic Fe matrix area and ii) an area with Cr-based carbides and ODS steel particles in the form of a $Fe-Fe_3C$ structure. In the commercial material, various hard Co-, Fe-Mo-, and Cr-based particles are present in a pearlitic Fe matrix. Wear testing using the VSR engine simulation wear test confirms that the seatface widths of the composite material with added ODS steel and the commercial material are increased by 24% and 47%, respectively, with wear depths of 0.05 mm and 0.1 mm, respectively. The ODS steel-added composite material shows better wear resistance. Post-wear-testing surface and cross-sectional observations show that particles in the commercial material easily fall off, while the ODS steel-added material has an even, smooth wear surface.

A novel approach for manufacturing oxide dispersion strengthened (ODS) steel cladding tubes using cold spray technology

  • Maier, Benjamin;Lenling, Mia;Yeom, Hwasung;Johnson, Greg;Maloy, Stuart;Sridharan, Kumar
    • Nuclear Engineering and Technology
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    • 제51권4호
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    • pp.1069-1074
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    • 2019
  • A novel fabrication method of oxide dispersion strengthened (ODS) steel cladding tubes for advanced fast reactors has been investigated using the cold spray powder-based materials deposition process. Cold spraying has the potential advantage for rapidly fabricating ODS cladding tubes in comparison with the conventional multi-step extrusion process. A gas atomized spherical 14YWT (Fe-14%Cr, 3%W, 0.4%Ti, 0.2% Y, 0.01%O) powder was sprayed on a rotating cylindrical 6061-T6 aluminum mandrel using nitrogen as the propellant gas. The powder lacked the oxygen content needed to precipitate the nanoclusters in ODS steel, therefore this work was intended to serve as a proof-of-concept study to demonstrate that free-standing steel cladding tubes with prototypical ODS composition could be manufactured using the cold spray process. The spray process produced an approximately 1-mm thick, dense 14YWT deposit on the aluminum-alloy tube. After surface polishing of the 14YWT deposit to obtain desired cladding thickness and surface roughness, the aluminum-alloy mandrel was dissolved in an alkaline medium to leave behind a free-standing ODS tube. The as-fabricated cladding tube was annealed at $1000^{\circ}C$ for 1 h in an argon atmosphere to improve the overall mechanical properties of the cladding.

항만 자동화를 위한 AGV 시스템의 장애물 감지 시스템의 구성에 관한 연구 (A Study on a Structure of Obstacle Detection System of AGV for Port Automation)

  • 박찬훈;최성락;박경택;김선호
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2000년도 추계학술대회논문집
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    • pp.227-234
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    • 2000
  • AGV is very proper equipment for Port Automation. AGV must have Obstacle Detection System(ODS) for port automation. Obstacle Detection System must have some functions. It must be able to classify some specified object from background data. And it must be able to track classified objects. Finally, ODS must determine its next action for safe cruise whether it must do emergency stop or it must speed down or it must change its track. For these functions, ODS can have many different structures. In this paper, we will propose one structure among some possible ones. Our ODS has been being developed using proposed structure since last year. In this paper, we will introduce our system which is under construction.

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고체상 추출법에 의한 콩나물 중의 잔류농약 동시 검출 (Simultaneous detection of residual fungicide in Bean Sprouts by Solid-phase Extraction)

  • 이명훈;이태준;표동진
    • 분석과학
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    • 제6권5호
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    • pp.509-514
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    • 1993
  • 콩나물(bean sprouts)에 잔류되어 있는 농약, benomyl, topsin-M과 thiram을 고체상 추출법(solid-phase extraction)과 HPLC를 이용하여 동시에 분석, 정량하는 방법을 개발하였다. 농약성분의 추출로는 ODS 카트리지(cartridge)를 사용하였고, 고정상으로는 $C_{18}$ 컬럼을 사용하였으며, 이동상으로는 40% $CH_3CN$ 수용액을 1ml/min의 유속으로 276nm에서 검출하였다. 콩나물에서 농약 성분을 추출하기 위한 전처리 방법으로 ODS 카트리지를 이용한 역상 추출방법을 이용하여 각각의 농약성분을 모두 검출할 수 있었다.

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