• 제목/요약/키워드: Nation

검색결과 3,991건 처리시간 0.037초

Synthesis of Platinum Nanoparticles Using Electrostatic Stabilization and Cluster Duplication of Perfluorinated Ionomer

  • Lee, Pyoung-Chan;Kim, Dong-Ouk;Han, Tai-Hoon;Kang, Soo-Jung;Pu, Lyong-Sun;Nam, Jae-Do;Kim, Byung-Woo;Lee, Jun-Ho
    • Macromolecular Research
    • /
    • 제17권3호
    • /
    • pp.187-191
    • /
    • 2009
  • Platinum (Pt) nanoparticles were prepared by the liquid-phase reduction of tetraammineplatinum (II) chloride $([Pt(NH_3)_4]Cl_2)$ using Nafion as a stabilizer under various conditions of the Nation phase. This method is novel in its use of electrostatic interactions between the Pt complex ions and sulfonic groups in the hydrated Nation molecules. The synthesized Pt nanoparticles of the recast film system had a cubic shape. In the case of the Nation solution system, the Pt nanoparticles mainly had a spherical shape. The shapes and sizes of the Pt nanoparticles were strongly influenced by the Nation phase.

도시 컴퓨팅 파일 시스템에서 미리 읽기 성능 향상을 위한 자료구조 (Data Structure Improving Prefetch Performance for Urban Computing File System)

  • 윤익준;고광진;신현식
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(A)
    • /
    • pp.311-312
    • /
    • 2012
  • 도시 컴퓨팅에서의 파일 시스템은 하나의 메타 데이터 서버와 여러 개의 데이터 저장 서버로 구성되어 있다. 이 데이터 저장 서버의 자료구조를 사용자의 두 가지 질의에 맞게 구성함으로써 미리읽기의 성능을 향상시킨다. 또한 데이터의 손실을 방지하기 위해 복사본을 만들 때, 두 가지의 형태로 바꿔 저장함으로써 데이터의 손실을 막고 여러 질의에 대응하여 좋은 성능을 낼 수 있다.

모형화 오차를 고려한 강인한 적응제어기의 설계 (Design of A Robust Adaptive Controller under Modeling Error)

  • 공재섭;김재민;양흥석
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1988년도 추계학술대회 논문집 학회본부
    • /
    • pp.80-83
    • /
    • 1988
  • In this paper a robust control law is presented which stabilezes overall system via pole reassignment and loop-shaping. A robust adaptive controller is designed combining this robust control law and a robust estimator.

  • PDF

3D 온라인 피팅 서비스 (3D Online Fitting Service)

  • 김호룡;윤호성;김동호
    • 한국방송∙미디어공학회:학술대회논문집
    • /
    • 한국방송∙미디어공학회 2021년도 추계학술대회
    • /
    • pp.245-247
    • /
    • 2021
  • 본 작품은 쇼핑의 발달 및 코로나로 인한 언택트 및 비대면 수요의 증가와 더불어 시간과 공간의 제약을 받지 않고 서비스를 이용할 수 있는 장점을 살려 만들었다. 어플리케이션에서 서버와의 연동을 통해 정보를 주고받으면서 웹페이지 안에 3D 모형과 각종 기능을 확인할 수 있고 이를 스마트폰 모바일 기기에서 간편하게 확인이 가능함으로써 다양한 쇼핑 기능들을 시각적으로 확인하고 활용할 수 있다.

  • PDF

A Study on High Performance Converter Topology for Hydrogen Gas Generation Electrolysis System

  • 강태원;고유란;서용석;정준익;노도환
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2010년도 하계학술대회 논문집
    • /
    • pp.196-197
    • /
    • 2010
  • This paper investigates a high performance converter topology for hydrogen gas generation electrolysis system. The proposed converter topology consists of full-bridge inverter, medium frequency transformer, and diode rectifier. Hydrogen gas generation electrolysis process considered in the paper is analyzed and characterized by its equivalent circuit. The electrolysis cell is modeled as effective resistance, capacitance, inductance, and internal emf voltage source. The proposed converter topology provides enhanced efficiency of hydrogen gas generation process under the operating condition of dc output voltage with high frequency ripple on it. The high performance operation of proposed converter is confirmed through the simulation with the electrolysis cell considered in the equivalent circuit model.

  • PDF

Advanced Liver Segmentation by Using Pixel Ratio in Abdominal CT Image

  • Yoo, Seung-Wha;Cho, Jun-Sik;Noh, Seung-Mo;Shin, Kyung-Suk;Park, Jong-Won
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2000년도 ITC-CSCC -1
    • /
    • pp.39-42
    • /
    • 2000
  • In our study, by observing and analyzing normal liver in abdominal CT image, we estimated gray value range and generated binary image. In the binary image, we achieved the number of hole which is located between pixels. Depending on the ratio, we processed the input image to 4 kinds of mesh images to remove the noise part that has the different ratio. With the Union image of 4 kinds of mesh images, we generated the template representing general outline of liver and subtracted from the binary image so the we can represent the organ boundary to be minute. With results of proposed method, processing time is reduced compared with existing method and we compared the result image to manual image of medical specialists.

  • PDF

Helical domain structure in laser-annealed Co-riched amorphous microwires

  • Lee, B. S.;Y. W. Rheem;Kim, C. G.;Kim, C. O.;S. S. Yoon;S. J. Ahn
    • 한국자기학회:학술대회 개요집
    • /
    • 한국자기학회 2002년도 동계연구발표회 논문개요집
    • /
    • pp.210-211
    • /
    • 2002
  • The magnetic anisotropy of amorphous wires plays a decisive role in the giant magnetoimpedance(GMI) behavior. The magnetoelastic anisotropy caused by internal stress, that are frozen in during the fabrication process, results in an axial easy axis in the core region and in a circular easy axis in the shell region [1]. It leads to a simple domain structure consisting of circular domains in the shell and axial domains in the core. For a more realistic domain structure, it has been suggested that the helical anisotropy exists due to an internal helical stress [2]. (omitted)

  • PDF