• Proceedings of the KIPE Conference
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• 전력전자학회 2014년도 추계학술대회 논문집
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• pp.105-106
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• 2014

본 논문에서는 디젤발전기와 에너지 저장 시스템, 태양광 발전을 이용한 스마트 그린 빌딩의 하이브리드 에너지 시스템을 제안한다. 빌딩 하이브리드 에너지시스템은 다양한 전력원을 가질 수 있는데 기존의 디젤발전기에 화석연료를 저감할 목적으로 풍력발전시스템이나 태양광발전시스템과 같은 형태의 신재생에너지원들이 연계 운전될 수 있다. 연료소모를 최소화하고 디젤발전기의 느린 출력응답특성으로 인한 계통 전압 불안정화를 보상하기 위해 응답특성이 빠른 배터리와 슈퍼커패시터로 이루어진 에너지저장장치와 태양광발전원과의 연계운전 기술을 제안하고 시뮬레이션 하였다.

• Proceedings of the Materials Research Society of Korea Conference
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.10.1-10.1
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• 2011

Energy harvesting technologies converting external sources (such as thermal energy, vibration and mechanical energy from the nature sources of wind, waves or animal movements) into electrical energy is recently a highly demanding issue in the materials science community for making sustainable green environments. In particular, fabrication of usable nanogenerator attract the attention of many researchers because it can scavenge even the biomechanical energy inside the human body (such as heart beat, blood flow, muscle stretching, or eye blinking) by converging harvesting technology with implantable bio-devices. Herein, we describe procedure suitable for generating and printing a lead-free microstructured $BaTiO_3$ thin film nanogenerator on plastic substrates to overcome limitations appeared in conventional flexible ferroelectric devices. Flexible $BaTiO_3$ thin film nanogenerator was fabricated and the piezoelectric properties and mechanically stability of ferroelectric devices were characterized. From the results, we demonstrate the highly efficient and stable performance of $BaTiO_3$ thin film nanogenerator and the integration of bio-eco-compatible ferroelectric materials may enable innovative opportunities for artificial skin and energy harvesting system.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.973-974
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• 2008

Optically transparent and flexible electronic circuits and displays are attractive for next-generation visual technologies, including windshield displays, head-mounted displays, and transparent screen monitors. Here we report on the fabrication of transparent transistors and circuits based on the combination of nanoscopic dielectrics and organic, inorganic, or hybrid semiconductors. Furthermore, the first demonstration of a transparent and flexible AMOLED display driven solely by $In_2O_3$ nanowire transistors (NWTs) is reported. The display region exhibits an optical transmittance of ~35% and a green peak luminance of ${\sim}300\;cd/m^2$. These results indicate that NWT-based drive circuits are attractive for fully transparent display technologies.

• IEIE Transactions on Smart Processing and Computing
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• 제5권2호
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• pp.143-151
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• 2016

This paper presents new prediction methods to improve compression performance of the so-called near-lossless RGB-domain image coder, which is designed to effectively decrease the memory bandwidth of a system-on-chip (SoC) for image processing. First, variable block size (VBS)-based intra prediction is employed to eliminate spatial redundancy for the green (G) component of an input image on a pixel-line basis. Second, inter-color prediction (ICP) using spectral correlation is performed to predict the R and B components from the previously reconstructed G-component image. Experimental results show that the proposed algorithm improves coding efficiency by up to 30% compared with an existing algorithm for natural images, and improves coding efficiency with low computational cost by about 50% for computer graphics (CG) images.

• Proceedings of the IEEK Conference
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.1137-1138
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• 2008

The purpose of this study is to implement a landscape lighting system that displays full color video by precisely controlling the R, G, B (Red, Green, Blue) LEDs which have a resolution of 256 each. The system implemented in this study consists of a PC, MASTER, SLAVEs and MODULEs. The PC sets the various landscape lighting displays, and the image files can be sent to the MASTER through a virtual serial port connected to the USB (Universal Serial Bus). The MASTER sends a sync signal to the SLAVE. The SLAVE uses the signal received from the MASTER and the landscape lighting display pattern.

• Proceedings of the IEEK Conference
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.349-352
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• 2001

Shape separation method - a separation process which utilizes the fact that particles of different shape behave differently in force fields- is regarded as an useful measure for recycling, mineral processing, upgrading powdered material and so on. In this study, a trial was given to shape separation method using fluid field to recover pure diatom skeleton - which is thought to have many uses in itself and potential for various applications -from low grade diatomaceous earth of southeastern part of the Korean Peninsula. The striking difference of shape between diatom skeleton and other minerals like clay and quartz made it natural to choose shape separation method. Considering the size of particles to be separated, among many possible methods of shape separation, hydrodynamic field using hydrocyclone was adopted. And it resulted in recovery of pure diatom skeleton with high purity

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제23권7호
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• pp.49-56
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• 2009

A new class of electronically commutated brushless motors, the flux-switching motor (FSM), is gradually emerging for use in power tools and household appliances especially fan and pump application thanks to green policies, This motor offers such advantages as high-power density and relatively high efficiency compare to induction motors, and low cost and simple motor structure compare to the BLDC motor. This paper presents the principle of the FSM and design of the 12/6 pole FSM drive system for fan application. Test results of the prototype motor are provided to verify the validity of the fan application with a TMS320F2812 DSP and inverter.

• Proceedings of the KIPE Conference
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.355-356
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• 2010

일반도로에서 자유주행이 가능한 온라인 전기자동차(On-Line Electric Vehicle, OLEV)에 적용하기 위해 전류원 급전방식의 직렬-직렬 공진형 자기유도 전력전달시스템(Inductive Power Transfer System, IPTS)을 개발하였다. OLEV용 IPTS에서는 급전선로의 누설 인덕턴스가 크고 집전픽업의 유무에 따라 입력측에 유기되는 전압변동이 심한 특성을 반영하여 급전측에 공진형 전류원을 사용한다. 또한 자화 인덕턴스와 집전픽업의 누설 인덕턴스를 포함하여 변압기를 완전 공진시킨다. 본 논문에서는 이러한 방식의 IPTS에서 최대출력을 전달하기 위한 조건을 찾고, 이로써 최대 출력전류 및 출력전력을 제한하는 요인을 찾아 최적설계를 할 수 있도록 하였다. 또한 실험을 통해 그 타당성을 검증하였다.

• Proceedings of the KIPE Conference
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.353-354
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• 2010

일반도로에서 주행 가능한 온라인전기자동차(On-Line Electric Vehicles)에 적용하기 위해 비접촉 자기유도 전력전달 방식의 초박형 급전코일과 집전코일을 개발하였다. 이러한 새로운 구조의 초박형 급집전코일은 코어비용을 대폭 절감하고 공극간격을 크게 해주며 차량 좌우편차를 크게 하여, OLEV가 경제적이면서도 성능이 탁월하게 하였다. 그 결과 양산단가 3억원/km 이하이면 서도 공극간격 17cm 이상, 효율 83%이상, 출력 60kW이상 등을 보여 실용화에 근접했다는 평가를 받고있다. 본 논문에서는 제안된 두 가지 방식 급집전코일의 주요 동작특성을 자기장 시뮬레이션 등을 통하여 검증하였다.

• Proceedings of the KIPE Conference
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.236-237
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• 2010

기존의 교류배전 시스템의 신재생 에너지원과의 연동 비용이성을 해결하고 전체 시스템의 효율을 높이기 위해 연구되고 있는 직류배전 시스템으로 전환하기 위해서는 옥내배선용 도선의 재검토가 필수적이다. 따라서 본 논문에서는 직류배전 전압 및 부하전류, 도선의 종류와 길이, 각종 규제사항 등을 고려하여 가정용 직류배전 시스템 적용에 적합한 도선 선정을 위한 가이드라인을 제시하고 이를 보급형 $100m^2$형 주택을 기준으로 한 시뮬레이션을 통해 타당성을 보인다.