• Title/Summary/Keyword: reset control

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Design of Readout Circuit With Smart Reset Control for Improving Dynamic Range of LWIR FPAs (초점면 배열 원적외선 검출기의 동작범위 향상을 위한 리셋 조정 회로)

  • Woo, Doo-Hyung
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.47 no.1
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    • pp.38-45
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    • 2010
  • A new readout circuit involving a pixel-level reset control was studied for 2-D long wavelength infrared focal plane arrays. The integration time of each pixel can be optimized individually and automatically. Hence, the readout circuit has a wide dynamic range and good signal-to-noise ratio characteristics. The readout circuit was fabricated with a $0.35{\mu}m$ 2-poly 4-metal CMOS process for a $128{\times}128$ long wavelength infrared HgCdTe array with a pixel size of $50{\mu}m{\times}50{\mu}m$. The smart reset control with two-step background suppression improves the signal-to-noise ratio to 87dB and the dynamic range to 95.8dB.

Measurement and Simulation of Heating Energy for Apartments with District Heating (지역난방 아파트에 대한 난방에너지 실측 및 시뮬레이션)

  • Lee, Eun Ju;Lee, Doo Young;Hong, Hiki;Kim, Young Kyun
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.12
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    • pp.572-578
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    • 2014
  • Heating energy was measured in an apartment housing unit with a district heating system, varying the kind of hot water distributors. Ondol coils passing through a living room raised the temperature of the room where the heating was turned off. Including this characteristic of Ondol heating into the modeling, we performed simulations and showed a verification by comparison with the results of measurements. As a result, a main flow control method, which changes hot water flow rate supplied to a housing unit according to the thermal load, can reduce the supplied flow rate and lower the return temperature, compared with a constant flow method. That can result in decreased heat loss in utility-pipe conduits even though the heating energy supplied is almost the same. An outdoor reset control that raises the temperature of the supplied hot water if the outdoor temperature falls has the effect of a quicker response in heating than the reduced flow rate and return temperature.

Analysis on a saturating system with an intelligent limiter

  • Yang, Sang-Sik
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.1091-1096
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    • 1989
  • All mechanical systems have saturation nonlinearity in actuators or in final control elements. When controllers have integral action, reset windup can cause instability as well as make the system performance unsatisfactory. In this study, an intelligent limiter which needs no tuning of parameters is tested with the PDF controller used for control of a second order plant. This paper presents analysis of the stability of the system using the describing function method and the Nyquist stability theorem. The improvement of the system performance by the limiter is illustrated by computer simulations.

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STABILITY ANALYSIS OF A CONTROL SYSTEM QITH AN ANTIRESET-WINDUP LIMITER BY LIAPUNOV'S SECOND METHOD

  • Yang, Sangsik
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1289-1294
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    • 1990
  • When a saturating control system has integral action, reset windup can cause instability as well as make the system performance unsatisfactory. An antirset-windup (ARW) limiter has been suggested to improve the stability and performance. It has been implemented with analog circuits and tested by simulations. This paper presents the stability condition of a double-integrator plant having the state feedback plus integral-action controller with the ARW limiter by using both Liapunov's second method and graphical method together.

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Performance Enhancement of Control Systems with Saturating Actuators (입력에 포화기를 가진 제어시스템의 성능향상)

  • 박종구;최종호
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.38 no.5
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    • pp.380-387
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    • 1989
  • The Conventional-Anti-reset-Windup (CAW) structure gives pretty good performance among the conventional strategies that prevent systems from saturation, but there is no systematic way of designing the control systems. Also, it frequently destabilizes the systems. Moreover, the CAW structure cannot be applied when the output of the saturating actuator cannot be measured. Therefore the CAW structure is modified to accommodate this situation. An effective designing method is proposed to give better performance of the control system. The stability of the control system is also considered. The usefulness of the proposed method is shown by applying this method to a few examples.

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Control techniques for improving response of the AVR (AVR의 응답속도개선을 위한 제어기법에 관한 연구)

  • Lee, Hyung-ki;Kim, Song-Hyun;Kim, Hyun-soo;Kim, Gi-ryang;Kim, Gwan-Hyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.11
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    • pp.2534-2539
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    • 2015
  • Method for regulating voltage using a generator voltage regulating device (AVR) is divided in an existing analog system and a digital replacement. Typically, to adjust the voltage by using a brushless excitation system of the type to be reduced for a voltage change under all. The control method of the AVR as a PID (proportional-integral-differential) control method is widely used. However, the control scheme is to reduce the transient response of the control parameters of the controller to the control object. Therefore, if the control target should change, there is a problem, reset the parameters of the controller again. In this study, without having to reset the parameters of the controller for the parameter variations to be controlled iPID (intelligent PID) using a controller designed to obtain a generator AVR system voltage variation is small in response to full load is applied to and through simulations and experiments improved transient response.

Performance Analysis of NTT/BT Protocol (NTT/BT 프로토콜의 성능 분석)

  • 이창훈;백상엽;이동주
    • Journal of the Korean Operations Research and Management Science Society
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    • v.22 no.2
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    • pp.99-123
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    • 1997
  • Performance analysis of NTT/BT protocol is investigated, which is a GFC (Generic Flow Control) ptotocol in ATM (Asynchronous Transfer Mode ) network and is based on cyclic reset mechanism. THe mean cell delay time is proposed as a performance measure of NTT/BT protocol. The mean cell delay time is defined as the duration from the instant the cell arrives at the transmission buffer until the cell is fully transmitted. The process of cell transmission can be described as a single server queueing modle with two dependent services. By utilizing this model, mean cell delay time is obtained and sensitivity of the factors such as window size and reset period is also analysed.

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PWM/PFM Dual Mode SMPS Controller IC for Active Forward Clamp and LLC Resonant Converters

  • Cheon, Jeong-In;Ha, Chang-Woo
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.7 no.2
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    • pp.94-97
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    • 2007
  • The desin and implementation of a CMOS analog integrated circuit that provides dual-mode modulations, PWM for active clamp reset converter and PFM for LLC resonant converter, is described. The proposed controller is capable of implementing programmable soft start and current-mode control with compensating ramp for PWM and frequency shifting soft start for PFM. Also it provides delay time for both modes. PWM mode is implemented by active clamp reset converter and PFM mode is implemented by LLC resonant convereter, respectively. The chip is fabricated using the 0.6um high voltage CMOS process.

A Study on Operating Position Sensing System of Pull Cord Switches Using Power Line Communication (전력선 통신을 이용한 풀 코드 스위치의 동작위치 인식 시스템에 대한 연구)

  • Choi, Nam-Sup;Lee, Buhm
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.745-748
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    • 2003
  • This paper presents a study on pull cord switch system which is employed in various industry for emergency stop of the equipments. By using power line communication(PLC) technique, in this paper, a new method for operation position detection of pull cord switch is suggested without complicated wiring of separate cables which utilize only 2 lines. Also, using control function of PLC IC, a reset signal for each switch reset can be implemented in the switch status control/sensing device. Finally, this paper shows validity and practical applicability of the proposed operating position sensing system of pull cord switch by implementing the system and revealing the response time and signal through the PLC line.

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Experimental and analytical study of a new seismic isolation device under a column

  • Benshuai Liang;Guangtai Zhang;Mingyang Wang;Jinpeng Zhang;Jianhu Wang
    • Earthquakes and Structures
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    • v.24 no.6
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    • pp.415-428
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    • 2023
  • Low-cost techniques with seismic isolation performance and excellent resilience need to be explored in the case of rural low-rise buildings because of the limited buying power of rural residents. As an inexpensive and eco-friendly isolation bearing, scrap tire pads (STPs) have the issue of poor resilience. Thus, a seismic isolation system under a column (SISC) integrated with STP needs to be designed for the seismic protection of low-rise rural buildings. The SISC, which is based on a simple exterior design, maintains excellent seismic performance, while the mechanical behavior of the internal STP provides elastic resilience. The horizontal behaviors of the SISC are studied through load tests, and its mechanical properties and the intrinsic mechanism of the reset ability are discussed. Results indicate that the average residual displacement ratio was 24.59%, and the reset capability was enhanced. Comparative experimental and finite element analysis results also show that the load-displacement relationship of the SISC was essentially consistent. The dynamic characteristics of isolated and fixed-base buildings were compared by numerical assessment of the response control effects, and the SISC was found to have great seismic isolation performance. SISC can be used as a low-cost base isolation device for rural buildings in developing countries.