• Journal of IKEEE
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• v.13 no.1
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• pp.36-40
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• 2009

In control of time delay systems, if the informations about the system model and the disturbance can be estimated exactly, the ideal response can be achieved by using Smith predictor controller. Therefore, in this paper, an adaptive algorithm is proposed to control time delay systems existing modelling errors and disturbance. An adaptive observer to estimate disturbance and system model is designed and adaptive laws adjusting the observer are proposed. The new Smith predictor controller is designed using the proposed adaptive observer. As a result, the proposed controller can eliminate the effects of the disturbance and the modelling error. The effectiveness and the improved performance of the proposed system are verified by computer simulation.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.5
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• pp.527-532
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• 2005

In this paper, we proposed an adaptive fuzzy sliding control for unknown nonlinear systems using estimation of bounds for approximation errors. Unknown nonlinearity of a system is approximated by the fuzzy logic system with a set of IF-THEN rules whose consequence parameters are adjusted on-line according to adaptive algorithms for the purpose of controlling the output of the nonlinear system to track a desired output. Also, using assumption that the approximation errors satisfy certain bounding conditions, we proposed the estimation algorithms of approximation errors by Lyapunov synthesis methods. The overall control system guarantees that the tracking error asymptotically converges to zero and that all signals involved in controller are uniformly bounded. The good performance of the proposed adaptive fuzzy sliding mode controller is verified through computer simulations on an inverted pendulum system.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.3
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• pp.59-66
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• 2010

This paper is proposed an adaptive fuzzy bilinear synchronization design for uncertain $L\ddot{u}$ chaos system. It is assumed that the $L\ddot{u}$ chaos system has unknown parameters. First, The $L\ddot{u}$ chaos system can be reconstructed via TS fuzzy bilinear modeling. We design an adaptive fuzzy bilinear synchronization control scheme based on TS fuzzy bilinear $L\ddot{u}$ chaos system with uncertain parameters. Lyapunov theory is employed to guarantee the stability of error dynamic system between TS fuzzy bilinear $L\ddot{u}$ chaos system and the proposed slave system and to derive the adaptive laws for estimating unknown parameters. Simulation results is given to demonstrate the validity of our proposed synchronization scheme.

• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.17-24
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• 2007

Critical practicality problems are cause to search the presentation and contents according to user request and purpose in previous internet system. Recently, there are a lot of researches about dynamic adaptable ontology based system. We designed ontology based educational system which uses discrete probability and user profile. This system provided advanced usability of contents by ontology and dynamic adaptive model based on discrete probability distribution function and user profile in ontology educational systems. This models represents application domain to weighted direction graph of dynamic adaptive objects and modeling user actions using dynamically approach method structured on discrete probability function. Proposed probability analysis can use that presenting potential attribute to user actions that are tracing search actions of user in ontology structure. This approach methods can allocate dynamically appropriate profiles to user.

• The Transactions of the Korea Information Processing Society
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• v.6 no.12
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• pp.3559-3568
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• 1999

The information overload with many information resources is an inevitable problem in modern electronic life. It is more difficult to search some information with user's information needs from an uncontrolled flood of many digital information resources, such as the internet which has been rapidly increased. So, many information retrieval systems have been researched and appeared. In text retrieval systems, they have met with user's information needs. While, in image retrieval systems, they have not properly dealt with user's information needs. In this paper, for resolving this problem, we proposed the intelligent user interface for image retrieval. It is based on HCOS(Human-Computer Symmetry) model which is a layed interaction model between a human and computer. Its' methodology is employed to reduce user's information overhead and semantic gap between user and systems. It is implemented with machine learning algorithms, decision tree and backpropagation neural network, for user adaptation capabilities of intelligent image retrieval system(IIRS).

• Journal of Digital Convergence
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• v.19 no.10
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• pp.39-48
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• 2021

This study aimed to analyze the level of professors' understanding and perception of adaptive learning and proposed how college can implement successful adaptive learning in college classes. For research purposes, online survey was conducted by 162 professors of A university in capital region. As a result, professors seemed to feel pressure to provide students personalized feedback and gave concerned that students don't study enough in advance before participating in class. It was also found that professors realized that they have low level of understanding about adaptive learning, while they revealed intention to make use of adaptive learning in their class. They also answered that adaptive learning system is the most helpful support for encouraging professors to apply adaptive learning in real class. We proposed what is required to encourage professor to implement adaptive learning in their class.

• Information and Communications Magazine
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• v.27 no.7
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• pp.36-41
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• 2010

본 논문에서는 개미 군집의 행동 생태를 모델로 하여 군집 시스템의 적응적 분업화, 전문화 특성을 살펴보고, 사물 통신 네트워크 분야로의 응용 가능성을 소개하고자 한다. 내 외적인 환경 변화에 대비하여 개미 군집이 어떻게 효율적인 관리와 전체 시스템의 운영 유지를 할 수 있는지는 시스템 관점의 분석 모델이 요구된다. 한 가능한 모델은 반응역(response threshold)과 일의 자극(task associated stimuli)의 관계로 적응적 반응함수를 사용하는 것이다. 본 논문에서는 적응적인 반응함수가 전체 군집의 효율성과 분업화 과정을 촉발시키는 형태로 발전하는 예제를 보여줄 것이다. 이러한 시스템 분석은 사물 통신 네트워크 분야 연구에 적용될 수 있고, 멀티 에이젼트 시스템에서 효율적인 정보 전송 및 유지, 노드 부하의 균등화, 통신 가능한 스웜 로봇의 업무 분업화 등 다양한 분야로 응용 가능성이 있음을 제안한다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.343-345
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• 2005

유비쿼터스 환경에서의 원격화상회의 시스템은 그 시스템을 이용하는 사용자에 따라서 시스템의 실행환경이나 사용자의 디바이스 환경 등 많은 변화 요소를 가지고 있다. 본 논문에서는, 사용자가 가질 수 있는 서로 다른 환경 등에 스스로 적응하여 효과적이고 최적화된 원격화상회의를 진행 할 수 있는 시스템 구조를 제안하며, 이를 이종의 플랫폼에서 구동할 수 있도록 각각의 플랫폼 환경에 최적화된 적응 구조를 동적으로 재구성할 수 있는 방법과 응용프로그램을 제안한다. 또한, 제안시스템의 프로토타입을 실제 구현하여 그 유효성을 확인하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5B
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• pp.439-447
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• 2011

It is a main concern for sustainable development in water resources management to evaluate adaptation capability of water resources structures under the future climate conditions. This study introduced the Fuzzy Inference System (FIS) to represent the change of release and storage of reservoirs in the Han River basin corresponding to various inflows. Defining the adaptation capability of reservoirs as the change of maximum and/or minimum of storage corresponding to the change of inflow, the study showed that Gangdong Dam has the worst adaptation capability on the variation of inflow, while Soyanggang Dam has the best capability. This study also constructed an Adaptive Neuro-Fuzzy Inference System (ANFIS) for the more accurate and efficient simulation of the adaptation capability of the Soyanggang Dam. Nine Inflow scenarios were generated using historical data from frequency analysis and synthetic data from two general circulation models with different climate change scenarios. The ANFIS showed significantly different consequences of the release and reservoir storage upon inflow scenarios of Soyanggang Dam, whilst it provides stable reservoir operations despite the variability of rainfall pattern.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.1130-1136
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• 2006

최근 무선디바이스의 확산과 함께 무선 네트워크 환경의 다양한 제약사항을 극복하고 항상 적절한 서비스 레벨을 유지하기 위한 'Adaptation'관련연구가 중요한 이슈가 되고 있다. 그러나 대부분의 기존 연구들은 무선디바이스의 문제에 주요 초점이 맞추어져 있으며, 실제 적응에 필요한 변환작업이 이루어지는 프록시 서버의 부하는 크게 고려되지 않고 있다. 하지만 실제로 컨텐츠의 포맷변환과 같은 작업은 많은 리소스가 소요되는 작업이며, 하나의 서버에서 이를 수행하는 경우 많은 작업부하가 집중된다. 이는 사용자가 증가함에 따라 더욱 심각해지며, 사용자의 컨텐츠 요청에 대한 응답시간을 증가시키는 결과를 초래한다. 따라서 본 논문에서는 계층적으로 구성된 주변 프록시들간에 협동작업을 통해, 적응에 필요한 작업의 부하를 분산시키고, 이를 통해 보다 빠르고 효율적인 서비스를 제공하는 새로운 프레임워크를 제안한다. 우리는 제안시스템을 평가하기 위해 프로토타입을 개발하여 Healthcare 시나리오에 적용하였으며, 작업량에 따라서 참여 프록시들에게 작업부하가 균등하게 분배되는 결과와, 이를 통해 적응 컨텐츠가 보다 빠르게 사용자에게 제공되는 결과로 시스템의 효율성을 증명하였다.