• 한국음향학회지
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• 제20권5호
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• pp.54-60
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• 2001

본 논문에서는 휴대폰용 부저, 진동자 기능이 하나의 소자로 통합된 다기능 복합소자의 특성을 해석하기 위한 등가회로 해석법을 연구하였다. 전형적인 복합소자 제품에 대하여 부저, 진동 모드에 각각에 대한 등가회로를 구성하여 그 특성을 계산하였다. 이를 위해 우선 복합소자의 각 모드에 대한 동작원리를 규명하고, 그 원리에 따른 등가회로를 구성하여 복합소자의 동작특성을 시뮬레이션 할 수 있는 해석툴을 완성하였다. 해석법의 타당성은 그 결과를 실험결과와 비교함으로써 밝혔고, 계산 결과와 실제 측정결과가 잘 일치함을 알 수 있었다.

• 한국항공운항학회지
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• 제8권1호
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• pp.67-81
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• 2000

An experimental study was performed on the time lag, lift and drag characteristics of a multi functional spoiler which is a device to increase lift and drag contrary to conventional spoiler which decrease lift and increase drag. In this study, a wind tunnel investigation was made of the effect of incidence angle, slot width, and chordwise location of multi functional spoiler on the time lag, lift and drag characteristics of a wing. The results indicate that the time lag of a multi functional spoiler is influenced mainly not only by the chordwise location of a spoiler but also by the slot width between spoiler and wing upper surface. Multi functional spoiler can reduce time lag effectively by slotting the trailing edge of spoiler with slot ratio (slot width devided by the wing chord length) between 0.05 and 0.1. Also, it shows that the lift and drag coefficients of the wing with the multi functional spoiler and trailing edge flap are increased by 20% and 80%, respectively, compared to the wing with trailing edge flap only.

• 디지털산업정보학회논문지
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• 제12권3호
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• pp.125-132
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• 2016

The European Telecommunication Standards Institute (ETSI) Technical Committee (TC) Reconfigurable Radio Systems (RRS) is standardizing the multi-mode Mobile Device (MD). The configuration of multi-mode MD is determined by the downloaded mobile communication standard software. In this paper, we introduce the Radio Library concept for multi-mode MD which is one of the key components of RRS standard. This paper also introduces the Standard Functional Block which is a part of Radio Library. A method for selecting efficiency SFBs for multi-mode MD is presented and a Radio Library is generated based on the selected SFBs. This paper also shows sample Standard Functional Block Set which included in Radio Library. In order to verify the compatibility of the generated Radio Library which was made by C language, we implement the LTE Rel-10 and Wi-Fi(802.11b) to show the efficiency of generating a mobile communication standard software based on the Radio Library. Then using the Prograph Visual Programming MartenTM 1.6.4, we compiled our LTE Rel-10 and Wi-Fi(802.11b) source code.

• Journal of Power Electronics
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• 제15권4호
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• pp.1054-1065
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• 2015

Multi-functional voltage source inverters (VSIs) have attracted increasing attention in recent years for their advantageous auxiliary services for power quality enhancement in autonomous microgrids. These types of VSIs can not only achieve a proper control scheme in autonomous mode but also cope with the prescribed power quality and stability requirements. These functionalities are integrated within the same device, thereby significantly improving the cost-effectiveness of microgrids while decreasing the investment and bulk compared with those of multiple devices with independent functionalities. Control strategies for power quality enhancement in autonomous microgrids using multi-functional VSIs are comprehensively reviewed in this paper. In addition, such VSIs are discussed in detail, and comparisons of which are also provided. Lastly, a number of future research directions for multi-functional VSIs are recommended.

• Smart Structures and Systems
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• 제7권5호
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• pp.379-392
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• 2011

This paper presents a multi-functional system, consisting of a magnetorheological (MR) damper and an electromagnetic induction (EMI) device, and its applications in stay cables. The proposed system is capable of offering multiple functions: (1) mitigating excessive vibrations of cables, (2) estimating cable tension, and (3) harvesting energy for wireless sensors used health monitoring of cable-stayed bridges. In the proposed system, the EMI device, consisting of permanent magnets and a solenoid coil, can converts vibration energy into electrical energy (i.e., induced emf); hence, it acts as an energy harvesting system. Moreover, the cable tension can be estimated by using the emf signals obtained from the EMI device. In addition, the MR damper, whose damping property is controlled by the harvested energy from the EMI device, can effectively reduce excessive cable vibrations. In this study, the multi-functionality of the proposed system is experimentally evaluated by conducting a shaking table test as well as a full-scale stay cable in a laboratory setting. In the shaking table experiment, the energy harvesting capability of the EMI device for wireless sensor nodes is investigated. The performance on the cable tension estimation and the vibration mitigation are evaluated using the full-scale cable test setup. The test results show that the proposed system can sufficiently generate and store the electricity for operating a wireless sensor node twice per day, significantly alleviate vibration of a stay cable (by providing about 20% larger damping compared to the passive optimal case), and estimate the cable tension accurately within a 2.5% error.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2899-2905
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• 2011

We have demonstrated that TPyPA can be used as an efficient multi-functional material for OLEDs; hole transporting material (HTL), blue and white-light emitter. The device based on TPyPA as the HTL exhibited an external quantum efficiency of 1.7% and a luminance efficiency of 4.2 cd/A; these values are 40% higher than the external quantum efficiency and luminance efficiency of the NPD-based reference device. The device based on TPyPA as a blue-light emitter exhibited an external quantum efficiency of 4.2% and a luminance efficiency of 5.3 $cdA^{-1}$ with CIE coordinates at (0.16, 0.14), the device based on TPyPA as a white-light emitter exhibited an external quantum efficiency of 3.2% and a luminance efficiency of 7.7 $cdA^{-1}$ with CIE coordinates at (0.33, 0.39). Also, TPyPA-based organic solar cell (OSC) exhibited a maximum power conversion efficiency of 0.35%. TPyPA-based organic thin-film transistors (OTFTs) exhibited highly efficient field-effect mobility (${\mu}_{FET}$) of $1.7{\times}10^{-4}cm^2V^{-1}s^{-1}$, a threshold voltage ($V_{th}$) of -15.9 V, and an on/off current ratio of $8.6{\times}10^3$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.97-97
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• 2010

We demonstrate the hybrid polymer-quantum dot based multi-functional device (Organic bistable devices, Light-emitting diode, and Photovoltaic cell) with a single active-layer structure consisting of CdSe/ZnS semiconductor quantum-dots (QDs) dispersed in a poly N-vinylcarbazole (PVK) and 1,3,5-tirs- (N-phenylbenzimidazol-2-yl) benzene (TPBi) fabricated on indium-tin-oxide (ITO)/glass substrate by using a simple spin coating technique. The multi-functionality of the device as Organic bistable device (OBD), Light Emitting Diode (LED), and Photovoltaic cell can be successfully achieved by adding an electron transport layer (ETL) TPBi to OBD for attaining the functions of LED and Photovoltaic cell in which the lowest unoccupied molecular orbital (LUMO) level of TPBi is positioned at the energy level between the conduction band of CdSe/ZnS and LiF/Al electrode (band-gap engineering). Through transmission electron microscopy (TEM) study, the active layer of the device has a p-i-n structure of a consolidated core-shell structure in which semiconductor QDs are uniformly and isotropically adsorbed on the surface of a p-type polymer core and the n-type small molecular organic materials surround the semiconductor QDs.

• 산업공학
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• 제10권1호
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• pp.155-167
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• 1997

The purpose of this study is to develop the program for efficient operation of a multi-functional surface mounting device(SMD) which mount various components on a printed circuit board(PCB). These components are provided by diverse types of feeders such as cassette, stick and tray feeders. The SMD has one or two heads. In the SMD, the positions of PCB and feeders and fixed, and the head moves to pick up a component from a feeder and to mount it on the PCB. The number of lanes occupied by each feeder and the nozzle used for each component can be different. We develop an off-line program to minimize the cycle-time of the SMD by studying the optimal assignment of feeders and the optimal mounting sequence of components. Graphical User Interface(GUI) is also developed. Additionally, we consider the line balancing problem which appears when two SMDs are used sequentially.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.961-970
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• 2009

지난 10여 년 동안 모바일폰과 같은 인터랙티브 기기들은 새로운 버전이 나올 때마다 새로운 기능들이 덧붙여지면서 점점 더 사용하기 복잡해졌다. 다기능 복합기기의 사용 복잡도를 줄이기 위한 한 가지 방법은 그것을 일관성 있게 설계하는 것이다. 일관성을 정의하기가 쉽지 않고 때로는 일관성 있게 디자인한 것이 오히려 사용성을 낮추는 경우도 존재하지만, 일반적으로 일관성 있게 설계된 시스템은 그 사용법을 더 배우기 쉽고, 기억하기 쉬우며, 에러가 덜 발생한다. 그러나 실제적으로 다기능 복합기기의 사용자 인터랙션 또는 인터페이스를 일관성 있게 설계하는 일은 쉽지 않다. 다기능 기기의 인터랙션 설계는 매우 많은 수의 설계 변수들과 그것들 간의 관계를 고려해야 하므로 많은 시간이 소요되고 디자인 에러가 발생하기 쉽다. 따라서, 이런 복잡한 설계 과정을 지원할 수 있는 방법론의 개발이 필요하다. 본 연구에서는 CUID (Consistent Design of User Interaction)라고 명명한 효과적이고 효율적인 인터랙션 설계 방법론을 개발하였다. CUID는 일관성 있는 인터랙션 설계를 위한 디자인 프로세스와 그것을 지원하는 소프트웨어 툴을 포함한다. 이 방법론은 물리적 또는 시각적인 일관성보다는 논리적 일관성에 초점을 맞추고 있으며, 태스크 절차의 설계, 각 시스템 상태에서 가능해야 하는 조작(기능)에 대한 결정, 그리고 가능한 조작(기능)들을 어떤 인터페이스 컨트롤(control)을 통해 수행하도록 할 것인지에 대한 결정을 주요한 설계 문제로 다룬다. 또한, 본 논문에서는 사례 연구를 통해 CUID의 효용성을 검증하였다.

• 한국광학회:학술대회논문집
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• 한국광학회 2004년도 제15회 정기총회 및 동계학술발표회
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• pp.298-299
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• 2004

We propose and theoretically analyze multi-functional integrated optical device based on figure-eight shaped birefringent Sagnac loops. Our analysis shows that the propose device exhibit many unique features which allows it to operate as a tunable high-Q comb filter with a good channel isolation, and the intensity transmission of the filter can be varied from zero to 100 percent.