• 제목/요약/키워드: improving method

검색결과 7,223건 처리시간 0.045초

전력계통 안정도 향상을 위한 STATCOM 안정화 장치 설계 (Design of STATCOM Stabiliser for Improving Power System Stability)

  • 이석오;정영민;문경준;황기현;박준호;이정관
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 A
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    • pp.149-151
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    • 2001
  • This paper proposes the design of STATCOM(static synchronous compensator) stabilizer for improving power system stability using fuzzy logic controller(FLC). The STATCOM DC voltage regulator contributes negative damping to the power system as the installation of STATCOM DC voltage regulator. STATCOM stabiliser is superimposed on the AC voltage regulator to compensate the negative damping effect. To evaluate usefulness of the proposed method, we perform the nonlinear simulation on a single-machine infinite bus system. As results of the simulations, the proposed method shows better control performance than PI controller in terms of damping effects.

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신뢰도 벡터 기반의 다단계 음성인식 (Multi-stage Speech Recognition Using Confidence Vector)

  • 전형배;황규웅;정훈;김승희;박준;이윤근
    • 대한음성학회지:말소리
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    • 제63호
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    • pp.113-124
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    • 2007
  • In this paper, we propose a use of confidence vector as an intermediate input feature for multi-stage based speech recognition architecture to improve recognition accuracy. A multi-stage speech recognition structure is introduced as a method to reduce the computational complexity of the decoding procedure and then accomplish faster speech recognition. Conventional multi-stage speech recognition is usually composed of three stages, acoustic search, lexical search, and acoustic re-scoring. In this paper, we focus on improving the accuracy of the lexical decoding by introducing a confidence vector as an input feature instead of phoneme which was used typically. We take experimental results on 220K Korean Point-of-Interest (POI) domain and the experimental results show that the proposed method contributes on improving accuracy.

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A Method for Improving Stopband Characteristics of a Dual-Band Filter

  • Lee, Ja-Hyeon;Lim, Yeong-Seog
    • Journal of electromagnetic engineering and science
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    • 제11권3호
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    • pp.186-191
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    • 2011
  • This paper presents a simple and effective method for improving stopband rejection characteristics of previously studied dual-band filters. Small electric couplings were applied to the symmetrically positioned shunt resonators, which divided each transmission zero into two transmission zeros without any effect on passbands. We were able to achieve improved stopband rejection characteristics by these additional transmission zeros. For the filter application, we designed a dual-band filter with improved stopband characteristics using microstrip quasi-lumped elements. The electric couplings that control the location of transmission zeros are controlled by the distance between symmetric open stubs of the filter. The filter was fabricated with a relative dielectric constant of 3.5 and a thickness of 0.76 mm. The fabricated filter has a small size ($14.6{\times}13.2{\times}0.76$ mm) and a low insertion loss when compared with conventional filters.

Immediate Effect of Kinesiology Taping on Gait Function in Stroke Patients with Foot Drop

  • Kim, Jinuk
    • 국제물리치료학회지
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    • 제11권2호
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    • pp.2060-2064
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    • 2020
  • Background: Recently, the kinesiology taping (KT) method was reported to be effective in improving walking ability in foot drop patients after stroke, but the clinical basis is still unclear. Objectives: The KT method was compared with ankle-foot orthotics (AFO) to investigate gait ability in foot drop patients after stroke. Design: Crossover study design. Methods: In this study, 11 stroke patients with foot drop participated. Walking ability of all subjects for both conditions (KT and AFO) was measured using the GAITRite system. The order of application of the two conditions was determined randomly by drawing lots. Wilcoxon signed-rank test was used to compare walking ability between the two conditions. The level of statistical significance was set at P<.05. Results: There were no significant differences between the KT and AFO methods in terms of velocity, cadence, step length, and stride length (P>.05, all). Conclusion: This study recommends KT as an alternative to the AFO, since KT provides evidence of preventing of foot drops and improving gait ability in stroke patient.

교환시스템의 서비스 품절수준 향상을 위한 소프트웨어 블록의 중요도 결정 (Determination of Importance of Software Blocks for Improving Quality of Service in Switching System)

  • 조재균
    • 한국정보시스템학회지:정보시스템연구
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    • 제8권1호
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    • pp.93-108
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    • 1999
  • The switching system is designed and developed to satisfy the performance design objectives recommended by ITU for call processing capacity and quality of service(QOS), etc. When the results by actual measurement at the system testing phase do not satisfy the performance design objectives, however, an effort is required to improve the performance. This paper presents a method for improving QOS by modifying the application programs for the switching system. In the proposed method, the sequence chart related to a delay time for call connection is modelled using PERT(Program Evaluation and Review Technique) network. Then, the criticality index of a message is calculated using Monte Carlo simulation to evaluate which message's processing time to decrease in order to decrease the delay time and thus to improve QOS. The criticality index of a block is also calculated to identify those software blocks that significantly contribute to the delay time.

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On the mechanism of vertical stabilizer plates for improving aerodynamic stability of bridges

  • Chen, Airong;Zhou, Zhiyong;Xiang, Haifan
    • Wind and Structures
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    • 제9권1호
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    • pp.59-74
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    • 2006
  • Vertical stabilizer plates have been found to be an effective aerodynamic measure to improve the aerodynamic stability of bridges either with an open cross section or with a streamlined box cross section in wind tunnel testings and have been adopted in some long span bridges. By taking an open deck II-shaped section and a closed box section as examples, the mechanism of vertical stabilizer plates for improving aerodynamic stability are investigated by using numerical simulation based on Random Vortex Method. It is found that vertical stabilizer plates can increase the amplitude of the heaving motion, and decrease that of the rotational motion of the bridge decks.

직류전자 접촉기의 아크 소호력 향상 요인 추정 (Estimating factor for Improving Arc Extinction Capability of DC Magnetic Switch)

  • 조현길;이은웅;김길수;김견묵;임수생;김준호;류종상
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.18-20
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    • 2001
  • This paper describes are quenching chambers of three type for Magnetic Switch and analyzes electromagnetic blowout force acting on the arc using 3D finite element method we make prototype device of each model and establish characteristics of arc quenching by measuring arcing time. This paper compares electromagnetic blowout to inverse arcing time. As the result this proposes the improving method for arc quen performance in DC magnetic switch.

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The Formulation of Semi-Transparent Gel Emulsion by the Liquid Crystal Emulsification Method

  • Kim, Jungil;Lee, Youngkeun;Kim, Yongmin;Yun, Seiyoung
    • 한국응용과학기술학회지
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    • 제35권4호
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    • pp.1478-1486
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    • 2018
  • Liquid crystals offer plenty of useful activities as improving the stability of emulsion, increasing moisturizing power, drug release, improving skin feeling and visual effect for cosmetics fields. In order to prepare stable semi-transparent gel emulsion, liquid crystal emulsification method was used. The emulsion stabilities of systems containing glycerin, fatty alcohols, surfactants, water and oil were investigated at various temperatures as time passed. The stabilities of all emulsions were evaluated by means of a polarizing microscope, SEM, rheometer, colorimeter and DSC. Even though the samples stored at $50^{\circ}C$ thermostatic chamber were occurred the reduction of hardness, turbidity and ${\Delta}H$ and the peak shift, the semi-transparent gel emulsion was very stable without separation between water and oils phase in emulsion.

Design of Learning Process with Code Reconstruction Principle for Non-computer Majors

  • Hye-Wuk, Jung
    • International Journal of Advanced Culture Technology
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    • 제10권4호
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    • pp.175-180
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    • 2022
  • To develop computational thinking skills, university students are learning how to solve problems with algorithms, program commands and grammar, and program writing. Because non-computer majors have difficulty with computer programming-related content, they need a learning method to acquire coding knowledge from the process of understanding, interpreting, changing, and improving source codes by themselves. This study explored clone coding, refactoring coding, and coding methods using reconstruction tools, which are practical and effective learning methods for improving coding skills for students who are accustomed to coding. A coding learning process with the code reconstruction principle was designed to help non-computer majors use it to understand coding technology and develop their problem-solving ability and applied the coding technology learning method used in programmer education.

항공기 공지통신 무전기 성능개량을 위한 자동 TOD 연동방안 연구 (The Study of Automatic TOD Synchronization for Air-Ground Radio Performance Improving in Legacy Aircraft)

  • 장진욱;안승범;최명석
    • 한국군사과학기술학회지
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    • 제25권3호
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    • pp.292-299
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    • 2022
  • In this paper, we proposed an automatic TOD synchronization and verification method for improving the performance of air-to-ground radio(hereafter SATURN) of legacy aircraft. In order to automatically synchronize TOD with SATURN radio, it is proposed to modify the GPS antenna installed in the existing aircraft according to the minimum operating performance standard. In addition, test methods and results are presented to verify the TOD information generation capability before and after the GPS antenna modifying. It is expected that the automatic TOD synchronization method proposed in this paper can be applied to the SATURN performance improvement design.