• Title/Summary/Keyword: Active method

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Design of Active Bandpass Filter Considering The Amplitude Flatness of Passband (대역 내 진폭 특성의 평탄도를 고려한 4단 능동 대역통과 여파기 설계)

  • Bang, Inn-Dae
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2003.11a
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    • pp.638-648
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    • 2003
  • An active capacitance circuit is analyzed in depth and its application to active RF BPF with low noise figure is discussed. The characteristics of the active capacitance circuit made of FET[1] exhibits negative resistance and conventional capacitance, which is easily controlled. However, it is difficult to make the negative resistance adequate in the designated frequency range due to the lack of detailed analysis, which could make an active circuit unstable as the frequency is going higher or lower. In this paper, we analyzed the negative resistance characteristics of active capacitance circuits and also presented the method that the flatness of passband can be controlled. Finally we have designed a 4-stage active BPE, which results in bandwidth of 100 MHz, 0,04 dB insertion loss, 0.2 dB ripple, and noise figure of 2.4 dB at 1.75 GHz band.

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Component Classification and Specification on Active Security Architecture (능동보안 아키텍쳐를 위한 컴포넌트 분류 및 명세방법)

  • 김상영;김재웅;황선명
    • Journal of Korea Multimedia Society
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    • v.7 no.1
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    • pp.113-125
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    • 2004
  • Active networks aim to provide a software framework that enables active network applications to customize the processing their communications. Active security component architecture focuses on the support of reuse system by active security component. The architecture is standard layer to acquire, understand, and assemble component, and it has to support a guideline for component identification, search and customization. In this paper we present the active security architecture as a standard model of discrete active network solution, and we propose the method for component classification and specification.

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Instantaneous Compensating Power Flow Graph of Active Power Filters Considering Rectification / Inversion Modes (정류와 역변환 모드를 고려한 능동전력필터의 순시 보상전력 흐름도)

  • 정영국;정찬수;배동관;안재영;김광헌;임영철
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.101-105
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    • 1999
  • The goal of this paper is to present instantaneous compensating power flow of active power filters(APFs) by graphical method that could be practicable to compensate the power in both case of behaving in instantaneous rectifying mode and instantaneous inverting mode. To ensure the validity of the proposed method, computer simulation is achieved. Proposed method can be present more exquisite and physically meaningful power flow than conventional method in instantaneous compensating power flow Graph of APFs.

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An Implementation of Stabilizing Controller for 2-Axis Platform using Adaptive Fuzzy Control and DSP

  • Ryu, Gi-Seok;Kim, Jin-Kyu;Park, Jang-Ho;Kim, Dae-Young;Kim, Jong-Hwa
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.71.3-71
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    • 2001
  • Passive Stabilization method and active stabilization method are mainly used to comprise a control system of platform stabilizer. Passive Stabilization method has demerits because of size and weight except that control structure is simple while active stabilization method using sensors can reduce size and weight, it requires high sensor technique and control algorithm. In this paper, a stabilizing controller using adaptive fuzzy control technique and floating-point processor(DSP) is suggested.

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Region Segmentation Technique Based on Active Contour for Object Segmentation (객체 분할을 위한 Active Contour 기반의 영역 분할 기법 연구)

  • Han, Hyeon-Ho;Lee, Gang-Seong;Lee, Jong-Yong;Lee, Sang-Hun
    • Journal of Digital Convergence
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    • v.10 no.3
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    • pp.167-172
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    • 2012
  • This paper presents the technique separating objects on the single frame image from the background using region segmentation technique based on active contour. Active contour is to extract contours of objects from the image, which is set to have multi-search starting point to extract each objects contours for multi-object segmentation. Initial rough object segments are generated from binary-coded image using object specific contour information, and then the hole filling is performed to compensate internal segmentation caused by the change of inner object hole area and pixels. This procedure complements the problems caused by the noise from the region segmentation and the errors of segmentation near by the contour. The proposed method and conventional method is compared to verify the superiority of the proposed method.

Calibration Method of Channels' Initial Phase Shift in Active Phased Array Antenna (능동 위상배열 안테나 채널의 초기위상 천이 보정 방법)

  • Mun, Yeong-Chan;Park, Chan-Gu;Pyo, Cheol-Sik;Jeon, Sun-Ik
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.37 no.7
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    • pp.18-23
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    • 2000
  • An active phased away antenna consists of many channels including radiator and active circuitary that contains low noise amplifiers and phase shifters. Each channel has different initial phase shift and gain because of inequality in active circuitary itself, interface between radiator and active circuitary, beam forming network and other antenna configurations. This is an inherent problem in active phased away antenna, therefore each channels' initial phase shifts and gains should be calibrated for obtaining the designed radiation pattern and antenna gain. In this paper, an efficient calibration method for the active phased array antenna is presented. By performing the above method, thhe antenna gain is increased more than 2.0 dB after calibrating considerably unequal 12 channels' initial phase shifts and gains.

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Anti-islanding using Active Frequency Shake Method for Grid-connected PV Generation System (계통연계형 태양광발전시스템의 AFS 기법을 이용한 단독운전 방지)

  • Ock, Seungkyu;Kang, Moonsung;Yang, Oh
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.1
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    • pp.127-136
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    • 2013
  • The islanding detection and prevention function in the important performance of the grid-connected inverter is the essential details which should be considered for worker's safety to maintain the system. This paper tries to suggest the active frequency shake islanding detection technique in the grid-connected PV generation system using sunlight. The existing active frequency drift method algorithm is described to suggest active frequency shake method algorithm. And, the algorithm which can reduce the non-detection zone, improve THD, and improve the detection speed in comparison with the existing algorithm is suggested. And we applied the proposed algorithm to the 3kW grid-connected photovoltaic inverter generation and verified the feasibility of the technique through the simulation and experiments.

Establishment and future tasks of estimated energy requirement in 2020 dietary reference intakes for Koreans (2020 한국인 에너지필요추정량 설정 및 앞으로의 과제)

  • Kim, Eun-Kyung;Kim, Oh Yoen;Park, Jonghoon;Kim, EunMi;Kim, Juhyeon
    • Journal of Nutrition and Health
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    • v.54 no.6
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    • pp.573-583
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    • 2021
  • Energy requirement is defined as energy expenditure in an energy equilibrium state. The doubly labeled water (DLW) method is considered the gold standard for measuring total energy expenditure (TEE). In 2002, the Institute of Medicine (IOM) of the National Academies established dietary reference intakes (DRIs) for Americans and Canadians, and the equations for estimated energy requirement (EER) were developed by using pooled data from studies that had applied the DLW method. Since 2005, these equations have been used for establishing EER in the DRI for Koreans. These equations based on age group include the physical activity (PA) coefficient determined by the PA level (PAL; sedentary, low active, active and very active) as well as body weight and height. The PAL values of Koreans calculated using the DLW method and PA diaries were determined to fall in the low active category (1.40~1.59). Therefore, the PA coefficient corresponding to 'low active' was applied to the EER equations. In recent years, with increasing number of people regularly engaging in various physical activities in Korea, EER is now separately presented for people with 'active' and 'very active' PALs. In the future, like the United States and Japan, Korea needs to expand the DLW research for developing EER predictive equations for Koreans. In addition, standardized guidelines should be prepared to accurately evaluate the PAL using the physical activity diary and the new PA classification table for Koreans.

A New Control Method of Series Active Power Filter with Harmonic Voltage Source (고조파 전압원에 대한 직렬형 능동전력필터의 새로운 제어법)

  • Ko, Soo-Hyun;Shin, Jae-Hwa;Kim, Young-Seok
    • Proceedings of the KIEE Conference
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    • 2002.07b
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    • pp.1033-1036
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    • 2002
  • This paper introduces a control method of series active power filter that compensate harmonic currents and eliminate a neutral line current in 3 phase 3 wire and 3 phase 4 wire power system with harmonic voltage source. These harmonic currents and neutral line current are caused by a nonlinear loads such as diode rectifiers and thyristor converters. Proposed methode extracts a voltage reference directly from performance function without phase transformation. Therefore, the control method is simpler than any other conventional methods. Experimental results for 3-phase 3-wire and 3-phase 4-wire series active power filter system were shown to verify the effectiveness of this control method.

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Active Control of Earthquake Responses Using Fuzzy Supervisory Control Technique (퍼지관리제어기법을 이용한 지진응답의 능동제어)

  • 박관순;고현무;옥승용
    • Journal of the Earthquake Engineering Society of Korea
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    • v.5 no.4
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    • pp.75-81
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    • 2001
  • Fuzzy supervisory control method is studied for the active control of earthquake excited structures. The proposed algorithm supervises and tunes previously designed control gains by evaluating the state of a structure through the fuzzy inference mechanism, which uses the information of relative displacements and velocities. Example designs and numerical simulations of earthquake exited three degrees of freedom structures are performed to prove the validity of the proposed control algorithm. Comparative results with conventional LQR method show that the proposed method is effective for the vibration suppression of earthquake excited structures.

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