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A Novel design of Composite Support for A Highly Active and Durable PEM Fuel Cell Catalyst
지윤성,조용일,전유권,황호정,전옥성,권오찬,김정필,설용건 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.0
Polymer electrolyte membrane fuel cell (PEMFC) has been granted extensive attention as a one of attractive electrochemical energy conversion devices. Because, it withholds many benefits such as high energy efficiency, high power density and rapid start up, etc. However, the main problem is the cost of generation still higher than conventional power generators. To overcome this hurdle, researchers are trying to reduce the usage of platinum. In order to use a less Pt catalyst per unit electricity production, more active catalyst with stable support needs to be developed. In this study, a novel composite nanofiber support was prepared by growing carbon nanofibers on the electrospun titania nanofiber using methane as a source. Platinum nanoparticles were deposited on the nanofibrous support by polyol method. Finally, the synthesized catalyst was showed higher activity and improved stability. These properties are characterized by XRD, SEM, TEM, and electrochemical measurements.
Fabrication and Analysis of a C-Pt/TiO2 nanofibrous electrode
지윤성,조용일,전유권,설용건 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.0
Recently, many researchers have taken great interest in high temperature polymer electrolyte membrane fuel cell (HT-PEMFC ≥100 ℃). However, Carbon corrosion is still a main problem for the PEMFC catalyst, where this is further accelerated at high temperatures. Therefore, electrochemically stable materials at operating conditions need to be developed to maintain a superior cell performance and durability. So, our approach takes advantages of the corrosion resistivity of TiO2 and electrochemical conductivity of carbon from the design of the CNT-Pt/TiO2 catalyst. From the single cell test, it reveals that C-Pt/TiO2 catalyst has significantly enhanced the performance and durability at the same time. All of these phenomena were resulted by the use of C-Pt/TiO2 catalyst is characterized by XRD, XPS, SEM, TEM and several electrochemical measurements.
Growing CNF on oxide support for making effective conducting pathways on PEMFCs
지윤성,전유권,조용일,설용건 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.1
Fuel cell is one of the most promising electrochemical energy conversion devices that withholds many advantages such as high efficiency, high power density, rapid start up, any significant pollutant, etc. Especially, polymer electrolyte membrane fuel cell (PEMFC) has been awarded substantial attention due to its high power density and relatively good portability. Generally, Pt supported on carbon black is used as the electrocatalyst for oxygen reduction reaction and thus improving the durability is essential for the commercialization of PEMFC. In order to develop a better catalyst, we prepared carbon-titanium dioxide nanofiber composite as a support material by growing carbon nanofibers (CNF) using methane as the source on the electrospun titania nanofiber. Platinum (Pt) nanoparticles were deposited on this nanofibrous support by Microwave-assisted polyol method. Then, synthesized catalyst was characterized by XRD, SEM, TEM, and electrochemical measurements.
심층강화학습 기반 데이터 전송률 향상을 위한 빔 자원 할당 기법
지윤성,박정재,심병효 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.2
최근 모바일 사용자들의 데이터 사용량이 급격하게 증가함에 따라 무선 통신에서의 데이터 전송률 향상 기법의 필요성이 대두되었다. 기지국과 연결된 사용자들의 데이터 요구량에 따라, 주파수 대역내에 한정된 빔 자원을 효율적으로 할당하는 방법이 필요하다. 본 논문에서는 심층강화학습을 이용한 빔 자원 블록 할당 기법을 제안한다. 시뮬레이션 결과에 따르면 제안된 기법을 통해 사용자들의 데이터 요구량을 충족하면서, 총 데이터 전송률을 향상시킬 수 있음을 확인하였다.
IRS 이용한 C-V2X 채널 용량 향상을 위한 자원 할당 기법
지윤성(Yoon Sung Ji),심병효(Byong Hyo Shim) 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.6
군집주행 및 자율 주행과 같은 미래 자동차 산업 기술을 위해서는 차량 간 통신에서의 높은 데이터 전송률 기준이 요구된다. 본 논문은 도심 환경에서의 C-V2X (Cellular Vehicle-to-Everything) 통신 채널 용량을 향상 시키기 위한 기법을 제안한다. DNN을 이용하여 Intelligent Reflecting Surface (IRS) 반사 소자의 위상 및 무선 자원 할당을 결정하는 딥러닝 알고리즘을 제안한다. 간단한 시나리오에서의 시뮬레이션을 통해 IRS 사용으로 Blockage가 심한 도심 환경에서도 차량 유저들의 서비스 요구량을 만족시키는 동시에 셀룰러 유저들의 채널 용량을 향상 시킬 수 있음을 보인다.