• Title/Summary/Keyword: continuous-time

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SLIDING MODE MOULD LEVEL CONTROL IN CONTINUOUS CASTING PROCESS

  • Kueon, Yeong-Seob
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.7 no.4
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    • pp.50-55
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    • 1998
  • Mould level control system for continuous casting process involves stick-slip friction in the sliding gate , time-delay, non-linearity, and certain uncertainties such as friction force variations between molten steel and the inner wall of mould. In this paper, sliding mode control technique was used to solve these complex control problem. The controller is then designed and implemented onto the continuous casting process. Testing result shows that sliding mode controller can decrease the fluctuating magnitude of the mould level and is superior to the existing PID controller.

A Real-Time Disk Prefetch Scheme for Continuous Media Playback (연속매체 상영을 위한 실시간 디스크 프리팻칭 기법)

  • Lim Sung Chae
    • The KIPS Transactions:PartA
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    • v.11A no.7 s.91
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    • pp.547-554
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    • 2004
  • To play back CM (Continuous Media) in online mode, the multimedia system Is required to have a real-time disk scheduling scheme that can efficiently fulfill the strict temporal constraints of serviced CM streams to prevent hiccups. In general, such disk scheduling is performed based on the concept of periodic prefetching since a CM stream has a rather long Playback time. In this paper, we also propose a periodic prefetching scheme that runs by using real-time disk channels, called on-time delivery channels. Since the channels are generated from the bulk-SCAN algorithm and they can be allocated in a very flexible manner based on the EDF (earliest-deadline-first) algorithm, the proposed scheme provides a better Performance in terms of I/O throughput and the average response time, as well as hiccup-free playback of concurrent CM streams. To show that the proposed scheme outperforms other methods, we give some simulation results.

A Study on the Information Technology and Competition Strategy - Focused on Continuous Competitive Advantage - (정보기술(IT)과 경쟁전략에 관한 연구 -지속적 경쟁우위와의 관련을 중심으로-)

  • Lim, Sang-Hyeok
    • International Commerce and Information Review
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    • v.8 no.1
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    • pp.15-31
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    • 2006
  • There is no overdoing of enforcement of the importance of strategical mind which indicates future direction when management environment around organizations are variously changing. This document describers preceding and comparison research about competition strategy, competitive advantage and IT centered on organizations' common issue "Guarantee of Continuous Competitive Advantage" and researched various factors to determined if Information Technology is functioning properly through the cases of excellent organizations operating continuous competitive advantage Continuous competitive advantage's source is evaluating positively about resource based view which is described by innovation of business process. However, reality of operating continuous competitive advantage with difficult imitation of business process' "Time" "Complexity" is insufficient. Confirm how continuous competitive advantage is operated in reality by accepting easy application of "Simple Concise" business process. Confirm existence of information technology capability creating difficult imitation is functioning as a source of continuous competitive advantage, not Information Technology resource supporting business process.

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A case report of a Phantom Limb Pain (PLP) patient treated with integrative Korean and Western medicine

  • Lee, Heun Ju;Baek, Ji Young;Ahn, Chang Beohm
    • Journal of Acupuncture Research
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    • v.34 no.3
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    • pp.101-107
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    • 2017
  • Objectives : We report a case of Phantom Limb Pain (PLP) and propose the possibility of integrative Korean and Western medicine in PLP treatment. Methods : For 42 days, a patient who complained of pain and insomnia with PLP (December 20, 2016 to January 20, 2017) received Korean and Western medical treatment. The patient was treated with analgesic injection, a neuropathic pain inhibitor, the combined herbal formula powders Bojungikgitang, and acupuncture. Symptom improvement was assessed using the numerical rating scale (NRS) and continuous sleep time. Results : The patient's NRS scores decreased, and continuous sleep time increased after treatment. The NRS scores decreased from 10 to 0, and the continuous sleep time increased from 2 hours to 7 to 8 hours. Conclusion : According to the results, this report suggests that integrative Korean and Western medicine could be effective in the treatment of PLP patients.

The Method of Continuous Nearest Neighbor Search on Trajectory of Moving Objects

  • Park, Bo-Yoon;Kim, Sang-Ho;Nam, Kwang-Woo;Ryo, Keun-Ho
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09a
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    • pp.467-470
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    • 2003
  • When user wants to find objects which have the nearest position from him, we use the nearest neighbor (NN) query. The GIS applications, such as navigation system and traffic control system, require processing of NN query for moving objects (MOs). MOs have trajectory with changing their position over time. Therefore, we should be able to find NN object continuously changing over the whole query time when process NN query for MOs, as well as moving nearby on trajectory of query. However, none of previous works consider trajectory information between objects. Therefore, we propose a method of continuous NN query for trajectory of MOs. We call this CTNN (continuous trajectory NN) technique. It ran find constantly valid NN object on the whole query time by considering of trajectory information.

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On the Fuzzy Control of Nonlinear Dynamic Systems with Inaccessible States

  • Kim, Kwangtae;Joongseon Joh;Woohyen Kwon
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1998.06a
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    • pp.331-336
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    • 1998
  • A systematic design method for PDC(Parallel Distributed Compensation)-type continuous time Takagi-Sugeno(T-S in short) fuzzy control systems which have inaccessible states is developed in this paper. Reduced-dimensional fuzzy state estimator is introduced from existing T-S fuzzy model using the PDC structure of Wang et al. [1] LMI(Linear Matrix Inequalities) problems which represent the stabililty of the reduced-dimensional fuzzy state estimator are derived. Pole placement constraints idea for each rules is adopted to determine the estimator gains and they are also revealed as LMI problems. these LMI problems are combined with Joh et al's [7][8] LMI problems for PDC -type continuous time T-S fuzzy controller design to yield a systematic design method for PDC -type continuous time T-S fuzzy control systems which have inaccessible states.

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Robust Dissipative Filtering for Polytopic Uncertain Singular Systems in Continuous & Discrete Time (연속과 이산시간 폴리토픽 불확실성을 가지는 특이시스템의 산일성 필터링)

  • Chan, Danny;Kim, Jong-Hae;Oh, Do-Chang
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.7
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    • pp.994-1000
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    • 2014
  • This paper considers the problem of continuous and discrete time dissipative filter design method for the singular systems with polytopic uncertainties. Two bounded real lemmas (BRL) for the robust filters of dissipative singular systems along with the polytopic uncertainties are proposed on the basis of Lyapunov criterion. The sufficient conditions for both continuous and discrete time dissipative filter design methods are derived using the obtained BRL by linear matrix inequality (LMI) approach. Finally, the validities of the proposed methods are shown by numerical examples.

Deviation - Propagation Models for Automating HAZOP Analysis of Batch Processes (회분식 공정의 HAZOP 분석 자동화를 위한 이탈전파 모델)

  • Ok You-Young;Hou Bo-Kyeng;Hwang Kyu-Suk
    • Journal of the Korean Institute of Gas
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    • v.3 no.2 s.7
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    • pp.34-42
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    • 1999
  • The discrete variables such as time and sequence must be considered for automating HAZOP analysis of batch processes in contrast with continuous processes. Because these variables can not be explained by the method used in the HAZOP analysis of continuous processes, we have developed the methodology for HAZOP analysis of batch processes on the basis of the relation between discrete variables and continuous ones. In this study, we have discussed the performance of the methodology on a Latex batch process to evaluate its effectiveness.

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Fuzzy Controller by Using Digital Redesign (디지털 재설계를 이용한 퍼지제어기)

  • Lee, Ho-Jae;Joo, Young-Hoon;Park, Jin-Bae
    • Proceedings of the KIEE Conference
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    • 1999.07b
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    • pp.630-632
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    • 1999
  • In this paper, we develop intelligent digitally redesigned PAM and PWM fuzzy controllers for nonlinear systems. Takagi-Sugeno fuzzy model is used to model the nonlinear systems and a continuous-time fuzzy-model-based controller is designed based on the extended parallel-distributed-compensation method. The digital controllers are determined from existing analogue controllers. The proposed method provides an accurate and effective method for digital control of continuous·time nonlinear systems and enables us to efficiently implement a digital controller via pre-determined continuous-time TS fuzzy-model-based controller. We have applied the proposed method to the balancing problem of the inverted pendulum to show the effectiveness and feasibility of the method.

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Design of a Continuous-Time Filter Using the Modified Chebyshev Function and DDA (개선된 Chebyshev 함수와 DDA를 이용한 연속시간 필터 설계)

  • 최석우;윤창훈;김동용
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.12
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    • pp.1572-1580
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    • 1995
  • In this paper, a modified Chebyshev low-pass filter function is proposed. The modified Chebyshev filter function exhibits ripples diminishing toward .omega. = 0 in the passband. So, the modified filter function is realizable in the passive doubly-terminated ladder network for the order n even or odd, thus lending itself amenable to active RC or switched capacitor filters through the simulation techniques. Besides the passive doubly-terminated ladder realizability, lower pole-Q values of the modified function are accountable for improved phase and delay characteristics, as compared to classical function. We have designed the 6th order passive doubly-terminated network using the modified function. And then a continuous-time DDA(Differential Difference Amplifier) filter, which has no matching requirement, is realized by leap-frog simulation technique for fabrication. In the HSPICE simulation results, we confirmed that the designed continuous-time DDA filter characteristics are agreement with the passive filter.

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