• PNF and Movement
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• 제12권1호
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• pp.1-5
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• 2014

Purpose: The purpose of this study was to investigate PNF exercises for balance ability in elderly. Methods: This is a literature study with books and articles. Results: The balance ability in elderly is reduced by decreasing proprioception, visual and vestibular sensation. PNF exercise is highly efficient for functional activities to control posture and movement. It is also highly efficient for balance ability in elderly. This is considered effective exercise program for maintain and to promote balance ability in elderly. Conclusion: PNF exercise is highly efficient for functional activities to control posture and movement. In addition, it is also efficient for balancing posture and movement in cooperation with visual information and vestibular system. This exercise is considered to be effective exercise program to maintain posture and improve balance ability.

• Journal of Information Display
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• 제10권2호
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• pp.87-91
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• 2009

Highly efficient red phosphorescent OLEDs (PHOLEDs) with a simple, organic, triple-layer structure was developed using the narrow-bandgap fluorescent host material bis(10-hydroxybenzo[h] quinolinato)beryllium complex (Bebq2) and the deep-red dopant tris(1-phenylisoquinoline)iridium (Ir(piq)3). The maximum current and power efficiency values of 12.71 cd/A and 16.02 lm/W, respectively, with an extremely low doping technology of 1%, are demonstrated herein. The results reveal a practical, cost-saving host dopant system for the fabrication of highly efficient PHOLEDs involving the simple structure presented herein, with a reduction of expensive Ir dopants.

• 전력전자학회논문지
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• 제19권3호
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• pp.227-232
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• 2014

A highly efficient MOSFET inverter for single-phase grid-connected photovoltaic power generation systems is presented in this paper. It is a full-MOSFET version of the conventional transformerless full-bridge inverter with dual L-C filters using unipolar PWM. The key idea lies on smart pre switching(SPS), which can make the large switching loss due to a poor reverse recovery of the MOSFET's body diode reduced dramatically. The validity of the proposed inverter is verified by experiment.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1103-1107
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• 2007

Highly efficient organic electroluminescent devices (OLEDs) based on 4,7- diphenyl-1, 10- phenanthroline (BPhen) as the electron transport layer (ETL), tris (8-hydroxyquinoline) aluminum ($Alq_3$) as the emission layer (EML) and N,$\acute{N}$-bis-[1-naphthy(-N,$\acute{N}$diphenyl-1,1´-biphenyl-4,4´-diamine)] (NPB) as the hole transport layer (HTL) were developed. The typical device structure was glass substrate/ ITO/ NPB/$Alq_3$/ BPhen/ LiF/ Al. Since BPhen possesses a considerable high electron mobility of $5\;{\times}\;10^{-4}\;cm^2\;V^{-1}\;s^{-1}$, devices with BPhen as ETL can realize an extremely high luminous efficiency. By optimizing the thickness of both HTL and ETL, we obtained a highly efficient OLED with a current efficiency of 6.80 cd/A and luminance of $1361\;cd/m^2$ at a current density of $20\;mA/cm^2$. This dramatic improvement in the current efficiency has been explained on the principle of charge balance.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1216-1219
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• 2009

Recently,electroluminescence devices based on organic semiconductors have made considerable progress. Displays based on organic light emitting diodes (OLED) are commercially available. To gain broader acceptance, the performance of OLED devices has to be further improved, in particular for lighting. This article discusses the possibility to use controlled electrical doping for improving the properties of devices and new approaches for highly efficient white OLED.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.817-819
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• 2009

We have developed highly efficient blue phosphorescent organic light-emitting devices (PHOLEDs) with simplified architectures using new host materials. The Blue PHOLED with new host:FIrpic emitting layer exhibits a maximum luminance efficiency of 34 cd/A and a low operating voltage 5 V at a high luminance of 1212 cd/$m^2$.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.482-485
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• 2009

We have fabricated transparent white organic light emitting diodes (WOLEDs) for lighting application. The structure property relationship of hybrid WOLEDs has been investigated and optimized devices showed high efficiency. Introduction of transparent cathode of LiF/Al/Ag into the hybrid WOLED led highly efficient WOLED with good transparency.

• 한국통신학회논문지
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• 제41권10호
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• pp.1301-1308
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• 2016

인터넷 속도의 증가와 다양한 응용의 개발로 인해 인터넷 사용자와 이들이 발생시키는 인터넷 트래픽의 양이 급격히 증가하고 있다. 트래픽 분석에 있어서 트래픽 응용 식별 방법은 페이로드 시그니쳐에 의존적이기 때문에 시그니쳐의 구성이나 개수에 따라 높은 부하와 처리 속도가 느린 단점을 갖는다. 따라서 본 논문에서는 응용 식별을 위한 페이로드 시그니쳐의 중요도를 평가하는 방법과 이를 바탕으로 높은 효율의 시그니쳐를 탐색하는 방법을 제안한다. 각 시그니쳐 별로 3가지 기준을 바탕으로 가중치를 계산하고 계산된 가중치와 시그니쳐 맵을 통해 고효율의 시그니쳐 세트를 탐색한다. 제안하는 방법을 실제 트래픽에 적용했을 때 기존 대비 약 4배의 응용 식별 능력을 가진 높은 효율의 시그니쳐들을 정의할 수 있었다.

• 한국재료학회:학술대회논문집
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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.

• 한국정보처리학회논문지
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• 제2권4호
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• pp.603-610
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• 1995

본 논문에서는 함수 기능에서 로직 게이트 기능까지 시뮬레이션 가능한 고성능의 로직 시뮬레이터(HSIM) 개발에 대해서 논한다. 개발된 로직 시뮬레이터는 입력부, 시 뮬레이터 본체, 출력부로 구성되어 있으며, 입력부에는 네트 리스트 컴파일러, 부품 정보 컴파일러가 포함된다. 시뮬레이터 본체에는 시뮬레이션 속도를 높이기 위한 각종 기술과 시뮬레이터의 중심 부분인 시뮬레이션 엔진 등이 소속되어 있다. 출력부에는 시뮬레이션 결과를 분석하는 파형 분석기가 있다. 개발된 시뮬레이터 본체의 주요 특 징은 점진적 로더를 사용하여 컴파일된 부품 기능들을 시뮬레이션 엔진에서 직접 로드 하여 시뮬레이션을 수행한다. 이렇게 한 결과 기존의 유릿 딜레어 event-driven interpretive 시뮬레이터와 비교했을 때 55% 이상 속도가 빠른 효과적인 성능 향상을 달성했다.