• Title/Summary/Keyword: rugged

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Tight adhesion of plastic substrates for cell gap stability in flexible LCDs

  • Jin, Min-Young;Kim, Sang-Il;Souk, Jun-Hyung;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.78-81
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    • 2008
  • We developed tight adhesion techniques of two plastic substrates to maintain cell gap stability for rugged flexible LCDs. By combining rigid spacers and several adhesion materials, we demonstrated mechanically very stable flexible LCDs against pressure and bending.

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SR Drive System for Electric Vehicle (전기자동차 구동용 SR Drive System)

  • Kim T.H.;Ahn J.W.;Park S.J.
    • Proceedings of the KIPE Conference
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    • 2003.07b
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    • pp.852-855
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    • 2003
  • The switched reluctance motor (SRM) is gaining much interest as a candidate for electric vehicle for its simple and rugged construction, ability of extremely high-speed operation. This paper is to design and investigate the capabilities of the SRM for low speed electric vehicle(LSEV)

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Maximum Output Control of Cage-Type Induction Generator for Wind Power Generation (풍력발전용 농형유도발전기의 최대출력제어)

  • Koo, Seoung-Young;Lee, Dong-Choon
    • Proceedings of the KIEE Conference
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    • 2001.04a
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    • pp.288-292
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    • 2001
  • In this paper, a maximum power control of a low-cost and rugged cage-type induction generator system is proposed, where the machine-side PWM converter is used for maximum power generation and field excitation control, and the line-side PWM inverter is used for the dc link voltage control and source-side power factor control. Simulation results through Matlab Simulink have been demonstrated.

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Traction IGBT Modules Design Issues and Precautions (전철용 IGBT 모듈 설계연구)

  • Gopal, Devarajan;Lho, Young-Hwan;Kim, Yoon-Ho
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.1853-1859
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    • 2008
  • IGBT modules are designed for low loss, rugged for all environments and user friendly. Low on state saturation voltage with high switching speed is the primary concerns. In this paper selection of IGBT, module ratings and characteristics are discussed. The IGBT design topic of protection against over voltage and over current are covered. Emphasis on turn off switching, short circuit switching and necessary precautions are dealt. Selection of IGBT device, gate drive power, and its lay out considerations are covered in detail.

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Simulink Model of 3-Phase Diode Rectifiers (3상 다이오드 정류기의 Simulink 모델)

  • Lee Jin-Woo
    • Proceedings of the KIPE Conference
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    • 2001.07a
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    • pp.514-519
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    • 2001
  • Most of inverters adopt a diode rectifier as an input stage, which has very simple and rugged structure and therefore low cost. In order to properly design the 3-phase diode rectifier with an output smoothing capacitor and input inductors, it is necessary to fully simulate the system due to its nonlinear characteristics. Therefore this paper describes the operating behaviors including the current commutation in detail by using the proposed equivalent circuit, and also proposes the Simulink-based model of the system. The simulation results show the validity of the proposed model in all operating conditions.

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LIMITATIONS OF SPHERE ANEMOMETRY FOR LOW GAS VELOCITY MEASUREMENTS

  • Han, J.Y.;O.F. Turan
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.297-304
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    • 1997
  • Sphere anemometry technique is re-visited for low gas velocity measurements during full-scale fire tests. This technique has the advantage of requiring only one channel per sphere for data acquisition, in addition to being cheap and rugged, The results indicate that the technique is useful for small fuel load burns with low radiation levels. For large fuel loads, the usefulness is up to sprinkler activation temperatures.

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Classification Strategies for High Resolution Images of Korean Forests: A Case Study of Namhansansung Provincial Park, Korea

  • Park, Chong-Hwa;Choi, Sang-Il
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.708-708
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    • 2002
  • Recent developments in sensor technologies have provided remotely sensed data with very high spatial resolution. In order to fully utilize the potential of high resolution images, new image classification strategies are necessary. Unfortunately, the high resolution images increase the spectral within-field variability, and the classification accuracy of traditional methods based on pixel-based classification algorithms such as Maximum-Likelihood method may be decreased (Schiewe 2001). Recent development in Object Oriented Classification based on image segmentation algorithms can be used for the classification of forest patches on rugged terrain of Korea. The objectives of this paper are as follows. First, to compare the pros and cons of image classification methods based on pixel-based and object oriented classification algorithm for the forest patch classification. Landsat ETM+ data and IKONOS data will be used for the classification. Second, to investigate ways to increase classification accuracy of forest patches. Supplemental data such as DTM and Forest Type Map of 1:25,000 scale are used for topographic correction and image segmentation. Third, to propose the best classification strategy for forest patch classification in terms of accuracy and data requirement. The research site for this paper is Namhansansung Provincial Park located at the eastern suburb of Seoul Metropolitan City for its diverse forest patch types and data availability. Both Landsat ETM+ and IKONOS data are used for the classification. Preliminary results can be summarized as follows. First, topographic correction of reflectance is essential for the classification of forest patches on rugged terrain. Second, object oriented classification of IKONOS data enables higher classification accuracy compared to Landsat ETM+ and pixel-based classification. Third, multi-stage segmentation is very useful to investigate landscape ecological aspect of forest communities of Korea.

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The effect of ambidextrous strategic balance on the management performance of venture businesses (양손잡이 전략균형이 벤처기업 경영성과에 미치는 영향)

  • Se-jong Yoo;Yong-seok Cho;Woo-hyoung Kim
    • Korea Trade Review
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    • v.48 no.1
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    • pp.83-126
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    • 2023
  • The revenue histogram of venture businesses is shifting from bell-shaped normal distribution to power-law distribution, which implies that the fitness landscape of the venture businesses ecosystem is changing to be more rugged terrain. We argue that the firm should adopt both exploitation (fast follower) and exploration (or first mover) strategies not to get stuck in local maxima in the rugged fitness landscape from the complex system perspective. By designing and performing agent-based modeling simulation experiments which consist of three types of agents (new technologies, entrepreneurs, and consumers), we demonstrated that the ambidexterity strategy showed the highest performance score in three of four different environment except 'Fast Widening' case where the exploitation strategy showed the highest performance score under low technology appropriation and fast disruptive technology development speed. By investigating the financial and other statistics of 617 top venture businesses who have earned 100B won or higher annual revenue, we concluded that 82% and 9% of firms are bent on the exploitation and exploration strategy.

Direct Torque Control of a Synchronous Reluctance Motor Using the Finite Element Method (유한요소법을 이용한 동기형 릴럭턴스 전동기의 직접토크제어 특성젠 관한 연구)

  • Lee, Moon-Ju;Kim, Sol;Lee, Ju;Ko, Kwon-Min;Kim, Tea-Duk;Oh, Sang-Kyeong
    • Proceedings of the KIEE Conference
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    • 2002.07b
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    • pp.666-668
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    • 2002
  • Reluctance torque is generated by the rotor of the rugged construction in Synchronous Reluctance Motor. Its construction is simple, and it is very economic because a rotor in existed AC motor can be used. As the Synchronous inductance in Synchronous Reluctance Motor is an element that is proportional to torque, the exact value must be experimentally or analytically found for controlling and the performance development of motors. In this paper, direct torque control simulation to maximize the torque of the Synchronous Reluctance Motor and fast response characteristics was carried out with the inductance value by the Finite Element Method. For the simulation results, there are torques and fluxs response characteristics when controlling speed.

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Measurement of Exhaust Gas Concentration using Wavelength Modulation Spectroscopy (파장 변조 기법을 이용한 연소배기 가스의 계측)

  • Kim, Dong-Hyuck;Kim, Se-Won;Shin, Myung-Chul;Kim, Yong-Mo
    • 한국연소학회:학술대회논문집
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    • 2006.10a
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    • pp.97-103
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    • 2006
  • This work forcus on the development of gas sensor that measure the concentrations of exhaust gas using diode laser. Each diode laser for exhaust gas measurement is set to work at near-IR using both DA and WMS methods. Also use of fiber-coupled optical elements makes such a sensor rugged and easy to align. On-line data acquisition and processing can be performed with a PC running LabVIEW software, and absorption signals are measured simultaneously by multiplexing method. Finally, It were experimentally compared WMS (Wavelength Modulation Spectroscopy) with DA (Direct Absorption) for the accuracy.

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