• Title/Summary/Keyword: Perfonnance

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Efficient Side Infonnation Generation Techniques and Perfonnance Evaluation for Distributed Video Coding System (분산 동영상 부호화 시스템을 위한 부가정보 생성 기법의 성능 평가)

  • Moon, Hak-Soo;Lee, Chang-Woo;Lee, Seong-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.3C
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    • pp.140-148
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    • 2011
  • The side information in the distributed video coding system is generated using motion compensated interpolation methods. Since the accuracy of the generated side information affects the amount of parity bits for the reconstruction of Wyner-Ziv frame, it is important to produce an accurate side information. In this paper, we analyze the informance of various side information generation methods and propose an effective side information generation technique. Also, we compare each side information generation methods from the hardware point of view and analyze the performance of distributed video coding system using various side information generation methods.

Design of a Fuzzy-Model-Based Controller for Nonlinear Systems (비선형 시스템을 위한 퍼지 모델 기반 제어기의 설계)

  • 주영훈
    • Journal of the Korean Institute of Intelligent Systems
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    • v.9 no.6
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    • pp.605-614
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    • 1999
  • This paper addresses analysis and design of a class of complex single-input single-output fuzzy control systems. In the proposed method, the fuzzy model, which represents the local dynamic behavior of the given nonlinear system, is utilized to construct the controller. The overall controller consists of the local compensators which compensate the local dynamic linear model and the feed-forward controller which is designed via sliding mode control theory. Therefore, the globally stable fuzzy controller is designed without finding a common Lyapunov matrix. and shows improved perfonnance and tracking results by taking the advantages of fuzzy-model-based control theory and sliding mode control theory. Furthennore, stability analysis is conducted not Ibr the fuzzy model but for the real underlying nonlinear system. Two numerical examples are included to show the effcctiveness and feasibility of the proposed fuzzy control method.

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Perfonnance Evaluation of Single Cell and Stack of PolymerElectrolyte Fuel Cell by Using Transfer Printing Technique

  • KIM, CHANG SOO;CHUN, YOUNG-GAB;PECK, DONG-HYUN;YANG, TAE-HYUN
    • Transactions of the Korean hydrogen and new energy society
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    • v.11 no.1
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    • pp.19-27
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    • 2000
  • The polymer electrolyte membrane fuel cell (PEMFC) system was developed. In order to enhance the performance of membrane electrode assembly (MEA), the transfer printing method of the electrocatalyst layer on membrane was developed. The $H_2/O_2$ single cell with an electrode area of $50cm^2$ was fabricated and tested using 20 wt.% Pt/C as an electrocatalyst and the commercial and hand-made MEA such as Nafion 115, Hanwha, Dow, Flemion T and Gore Select. The 100-cell PEMFC stack with an active electrode area of $300cm^2$ was designed and fabricated using 40 wt.% Pt/C and 30 wt.% Pt-Ru/C as a cathode and anode electrocatalysts, respectively. The performance of PEMFC system was obtained to be 7kW (250A at 28V) and 3.5kW (70A at 50V) at $80^{\circ}C$ by flowing $H_2/air$ and methanol reformed fuel gas/air, respectively.

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Effect of Ionic Enhancers in the Iontophoresis of Lidocaine (리도케인의 이온토포레시스에 있어서 이온 피부투과증진제의 영향)

  • Kim, Jae-Hong;Shin, Byung-Chul;Choi, Ho-Suk;Kim, Sung-Soo;Park, Young-Do
    • Journal of Pharmaceutical Investigation
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    • v.29 no.3
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    • pp.171-177
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    • 1999
  • Lidocaine(2-Diethylaminoaceto-2', 6'-xylidide) was transdennally delivered by iontophoresis and the effect of enhancer on the delivery of lidocaine was studied. We delivered lidocaine through the skin of hairless mouse using diffusion cell and investigated the effect of the amount of cation salts such as sodium chloride, calcium acetate, zinc acetate and aluminum acetate on the drug delivery. The amounts of transported drugs and adsorbed metal ions were measured by HPLC(High Perfonnance Liquid Chromatography) and AAS(Atomic Absorption Spectrophotometry), respectively. The addition of zinc acetate and aluminum acetate greatly enhanced the delivery of lidocaine. The detection of two metal ions by AAS seemed to support the idea that the astringency effect of these ions were the main reason for the enhancement of transdermal delivery.

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Chemosystematics and Molecular Phylogeny of a New Bioflocculant-Producing Aspergillus Strain Isolated from Korean Soil

  • Kim, Gi-Young;Ha, Myoung-Gyu;Lee, Tae-Ho;Lee, Jae-Dong
    • Journal of Microbiology and Biotechnology
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    • v.9 no.6
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    • pp.870-872
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    • 1999
  • The ubiquinone and G+C contents of the bioflocculant-producing fungus, a new Aspergillus strain, were detennined using high-perfonnance liquid chromatography. The internal transcribed spacers 1 and 2 (ITS1 and ITS2), and the 5.8S ribosomal DNA (rDNA) of the strain were amplified and sequenced. The strain contained ubiquinone-l0($H_2$)as a major quinone and the G+C content was 49 mol%. A phylogenetic analysis of the ITS regions indicated that the strain belonged to the genus Aspergillus according to its previously classified morphological characteristics. Based on a sequence homology search, the strain was most closely related to Petromyces muricatus (anamorph, A. muricatus; accession number, AJ005674). The sequence of a new Aspergillus strain in ITS1 and ITS2, and 5.8S rDNA showed 97% homology to P. muricatus. Therefore, the strain is believed to be a new bioflocculant-producing Aspergillus strain.

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Design and Implementation of Fuzzy Controller with Robest Performance for DC-CD Converters (DC-DC 컨버터를 위한 강인한 성능을 가지는 퍼지제어기의 설계 및 구현)

  • 이선근;권오석
    • The Transactions of the Korean Institute of Power Electronics
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    • v.4 no.6
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    • pp.531-538
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    • 1999
  • This paper proposes a fuzzy logic controller(FLC) for DC-DC converters in order to obtain good l perfonnances that can not be achieved by linear control tc'Chniques in the presence of wide parameter v variations. 'While the standard controller uses error and derivative of e$\pi$or, the proposed controller uses state v variables. Such method is ve$\pi$ efficient in case of DC-DC converters and can guarantee both stable s small-signal responses and improved large signal responses. The presented approach method is general and c can be applied to any dc-dc converter topologies. Through the simulations of booster, we verify the pro[Xlsed C control tc'Chnique can give a satisfactory perfonnance.

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A Mock Running And Transient State Test of Propulsion VVVF Inverter for Electric Locomotive using A Inertia Load (관성부하를 이용한 전동차 추진용 VVVF 인버터의 모의주행 및 과도상태시험)

  • 정만규;서광덕
    • The Transactions of the Korean Institute of Power Electronics
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    • v.4 no.6
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    • pp.491-499
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    • 1999
  • This paper is on the high perfonnance propulsion IGBT VVVF inverter adopted new technique for railways. To prove the high performance and stabilit~r of traction, running tests are carried out under the simulated condition alike real field. The tests are perfonned on not only a steady states but also a transient states such a as input voltage variation using inertia load equivalent to 160tons train. The vector control technique is a adopted to improve traction for 4 motors. The low switching synchronous PW1\l method based on a space v voltage vector modulation is pro\XlSed as the optimal method for propulsion system railway. The output voltage l is controlled continuously to six step by prolxlsed ovennodu]ation technique without sudden torque variation.

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LMS based Iterative Decision Feedback Equalizer for Wireless Packet Data Transmission (무선 패킷데이터 전송을 위한 LMS기반의 반복결정 귀환 등화기)

  • Choi Yun-Seok;Park Hyung-Kun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.7
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    • pp.1287-1294
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    • 2006
  • In many current wireless packet data system, the short-burst transmissions are used, and training overhead is very significant for such short burst formats. So, the availability of the short training sequence and the fast converging algorithm is essential in the adaptive equalizer. In this paper, the new equalizer algorithm is proposed to improve the performance of a MTLMS (multiple-training least mean square) based DFE (decision feedback equalizer)using the short training sequence. In the proposed method, the output of the DFE is fed back to the LMS (least mean square) based adaptive DEF loop iteratively and used as an extended training sequence. Instead of the block operation using ML (maximum likelihood) estimator, the low-complexity adaptive LMS operation is used for overall processing. Simulation results show that the perfonnance of the proposed equalizer is improved with a linear computational increase as the iterations parameter in creases and can give the more robustness to the time-varying fading.

A Study on Current Waveform Control and Performance Improvement for Inverter Arc Welding Machine (인버터 아크 용접기의 파형제어기법 및 성능향상에 관한 연구)

  • 채영민;고재석;김진욱;이승요;최해룡;최규하
    • The Transactions of the Korean Institute of Power Electronics
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    • v.4 no.2
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    • pp.128-137
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    • 1999
  • Recently the pelionnance of CO2 arc welding machine has been advanced significantly through the adoption of i invelter circuit topology. which made it possible to improve welding perfonnances such as spatter generation and bead s state. But the conventional inverter arc welding machine generates constant output voltage which cause much spatter g generation dUling short-circuit and arc start time because it is unable to control output current instantaneously. So this p paper representes wavefCnm controlled inverter arc welding machine which control the wavefonn of welding current and t thus to suppress the spatter generation. And the system designed in this paper is the digital controller using single chip m microprocessor of 80C196KC. As a result of perfonnance test for this system, the spatter generation is reduced and s shOlt-circuit time period is stabilized compared to conventional one. And more by using switched mode rectifier for A AC/DC power convelter. unity power factor is maintained and low order halmonic spectrum is supressed.

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Measurement-Based Adaptive Statistical Admission Control Scheme for Video-On-Demand Servers (주문형 비디오 서버를 위한 실측 기반 적응형 확률 승인 제어 기법)

  • Kim, In-Hwa;Kim, Jeong-Won;Lee, Seung-Won;Chung, Ki-Dong
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.12
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    • pp.3794-3803
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    • 2000
  • In a Video-on-Demand system, admission control that is used to serve multimedia data efficiently has to be perfonned by an accurate grasp of the condition of surplus resources. Most of all. we need to adaptable admission control mechanism because the disk has irregular response time caused by external elements of disk, and also has high deviation of amount demanded. In previous admission control schemes, they determined whether a new user is granted or not through a theoretical value. Although they based on the measurement, they left much to be desired in dealing with the service state. Measurement ~based statistical admission control scheme, as we su~~ested in this research, perfonns 2 processes of off-line process and on-line process in real service environment. Through this processes, we can grasp the accurate resource state of system and adaptive!y detennine the admission according to circumstances. Therefore, it can guarantee both maximum resource utilization and QoS(Quality of Service). On performance evaluations, we show that the video server can utilize maximum resource utilization with QoS guarantee through precision of perfonnance by measurement and adaptable admission control according to the requested bandwidth.

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