• Title/Summary/Keyword: self-adaptive method

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Background Removing for Digital image self-adaptive acquisition in medical X-ray imaging

  • Li, Xun;Kim, Young-Ju;Song, Young-Jun
    • International Journal of Contents
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    • v.4 no.1
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    • pp.12-15
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    • 2008
  • In this paper, we propose a new method of background removing for digital self-adaptive acquisition in medical X-ray imaging. We analysis the construction of video digital acquisition system and main factors of acquired image quality, propose a more efficiency method to against background non-uniformly. With proposed method, non-uniform illumination back ground was well removed without image quality degradation.

Study on the pressure self-adaptive water-tight junction box in underwater vehicle

  • Huang, Haocai;Ye, Yanying;Leng, Jianxing;Yuan, Zhuoli;Chen, Ying
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.4 no.3
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    • pp.302-312
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    • 2012
  • Underwater vehicles play a very important role in underwater engineering. Water-tight junction box (WJB) is one of the key components in underwater vehicle. This paper puts forward a pressure self-adaptive water-tight junction box (PSAWJB) which improves the reliability of the WJB significantly by solving the sealing and pressure problems in conventional WJB design. By redundancy design method, the pressure self-adaptive equalizer (PSAE) is designed in such a way that it consists of a piston pressure-adaptive compensator (PPAC) and a titanium film pressure-adaptive compensator (TFPAC). According to hydro-mechanical simulations, the operating volume of the PSAE is more than or equal to 11.6 % of the volume of WJB liquid system. Furthermore, the required operating volume of the PSAE also increases as the gas content of oil, hydrostatic pressure or temperature difference increases. The reliability of the PSAWJB is proved by hyperbaric chamber tests.

A Reusable Adaptation Strategy Extraction System for Developing Self-Adaptive Systems (자가 적응 시스템의 개발을 위한 재사용 가능한 적응 전략 추출 시스템)

  • Nam, Jungsik;Lee, Sukhoon;Baik, Doo-Kwon
    • KIPS Transactions on Software and Data Engineering
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    • v.4 no.3
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    • pp.111-120
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    • 2015
  • Recently, self-adaptive system researches have been done to solve the problems occurred in the dynamic environment. Designing requirement in the self-adaptive system is necessary to recognize and solve the problem for the system, and if a developer reuses existing adaptation strategy to design the requirement, the designing time and cost would be reduced. Therefore, this paper proposes the system which extracts reusable adaptation strategy from the existing self-adaptive system. For the proposal, this paper conceptualizes the self-adaptation elements, defines the adaptation strategy ontology and target system ontology, and presents the process of extracting reusable strategy. This paper also implements proposed system and evaluates the reuse rate of the extracted strategy. As a result, the adaptation strategies extracted by proposed system are exactly operated, and the extraction method of proposed system shows higher reuse rate than a previous method.

Design of Adaptive Velocity Controller for Wind Turbines Using Self Recurrent Wavelet Neural Network (자기회귀 웨이블릿 신경망을 이용한 풍력 발전 시스템의 적응 속도 제어기 설계)

  • Song, Seung-Kwan;Choi, Yoon-Ho;Park, Jin-Bae
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1691-1692
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    • 2008
  • In this paper, the adaptive neural network technique is proposed to control the speed of wind power generation system. For maximizing generated power effectively, adaptive neural algorithm based on SRWMM(Self Recurrent Wavelet Neural Network) is derived to on-line adjust the excitation winding voltage of the generator. Through computer simulations, it is shown that the proposed method can achieve smooth and asymptotic rotor speed tracking.

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Requirements Elicitation and Specification Method for the Development of Adaptive User Interface (적응형 사용자 인터페이스 개발을 위한 요구사항 도출 및 명세 기법)

  • Park, Kibeom;Lee, Seok-Won
    • Journal of KIISE
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    • v.44 no.1
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    • pp.27-35
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    • 2017
  • Many studies have addressed 'Adaptive User Interface (AUI)', wherein the user interface changes in accordance with the situation and the environment of each user at runtime. Nevertheless, previous papers for AUI barely reflected the viewpoints from requirements engineering field, since most of them focused on proposing the architecture and design. In this study, we outline AUI with the perspective of requirements engineering and propose the requirements elicitation and specification method based on concepts which have been researched in the area of self-adaptive system. Step by step, we first redefine and reinterpret the well-known concepts of self-adaptive software, after which the AUI requirements are elicited and specified. Finally, we illustrate a case study, which demonstrates the effectiveness of our method.

Optimal proportioning of concrete aggregates using a self-adaptive genetic algorithm

  • Amirjanov, Adil;Sobol, Konstantin
    • Computers and Concrete
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    • v.2 no.5
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    • pp.411-421
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    • 2005
  • A linear programming problem of the optimal proportioning of concrete aggregates is discussed; and a self-adaptive genetic algorithm is developed to solve this problem. The proposed method is based on changing a range of variables for capturing the feasible region of the optimum solution. A computational verification of this method is compared with the results of the linear programming.

Fuzzy logic control of a planar parallel manipulator using multi learning algorithm (다중 학습 알고리듬을 이용한 평면형 병렬 매니퓰레이터의 Fuzzy 논리 제어)

  • Song, Nak-Yun;Cho, Whang
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.8
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    • pp.914-922
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    • 1999
  • A study on the improvement of tracking performance of a 3 DOF planar parallel manipulator is performed. A class of adaptive tracking control sheme is designed using self tuning adaptive fuzzy logic control theory. This control sheme is composed of three classical PD controller and a multi learning type self tuning adaptive fuzzy logic controller set. PD controller is tuned roughly by manual setting a priori and fuzzy logic controller is tuned precisely by the gradient descent method for a global solution during run-time, so the proposed control scheme is tuned more rapidly and precisely than the single learning type self tuning adaptive fuzzy logic control sheme for a local solution. The control performance of the proposed algorithm is verified through experiments.

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A fast adaptive numerical solver for nonseparable elliptic partial differential equations

  • Lee, June-Yub
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.2 no.1
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    • pp.27-39
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    • 1998
  • We describe a fast numerical method for non-separable elliptic equations in self-adjoin form on irregular adaptive domains. One of the most successful results in numerical PDE is developing rapid elliptic solvers for separable EPDEs, for example, Fourier transformation methods for Poisson problem on a square, however, it is known that there is no rapid elliptic solvers capable of solving a general nonseparable problems. It is the purpose of this paper to present an iterative solver for linear EPDEs in self-adjoint form. The scheme discussed in this paper solves a given non-separable equation using a sequence of solutions of Poisson equations, therefore, the most important key for such a method is having a good Poison solver. High performance is achieved by using a fast high-order adaptive Poisson solver which requires only about 500 floating point operations per gridpoint in order to obtain machine precision for both the computed solution and its partial derivatives. A few numerical examples have been presented.

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The Frequency-Domain LMS Second-order Adaptive Volterra Filter and Its Analysis (주파수영역LMS 2차 적수Volterra 필터와 그 분석)

  • 정익주
    • The Journal of the Acoustical Society of Korea
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    • v.12 no.1
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    • pp.37-46
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    • 1993
  • The adaptive algorithm for the Volterra filter is considered. Owing to its simplicity, the LMS algorithm for adaptive Volterra filter(AVF) is widely used as in linear adaptive filters. However, the convergence speed is unsatisfactory. For improving the convergence speed, the frequency domain LMS second order adaptive Volterra filter(FLMS-AVF) is proposed and analyzed. We show that the time and frequency domain LMS AVF's have the same steady state performance under approprate conditons. Moreover, it can be shown that this algorithm can improve the convergence speed significantly by applying self-orthogonalizing method.

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Service-Dependability-Case based Self-Adaptation in Service-Oriented Environment (서비스 지향 컴퓨팅 환경에서 서비스 안정성 케이스 기반 자가 적응 방법)

  • Jung, Changhee;Lee, Seok-Won
    • Journal of KIISE
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    • v.42 no.11
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    • pp.1339-1348
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    • 2015
  • In a distributed system environment based on a service-oriented architecture, separate systems collaborate to achieve the goals of the entire system by using services provided other systems. A service quality violation from using one service can cause runtime system failure in the environment. The existing self-adaptation methods follow fault tolerance mechanism that responds to a failure after a service quality violation. In other words, these methods are limited to responsive action. Therefore, a service-dependability-case based self-adaptation mechanism is necessary to preserve the dependability of the self-adaptive system. This paper demonstrates that the service-dependability-case based self-adaptation mechanism is better than QoS(quality of service)-based self-adaptation with fault tolerance to preserve the dependability of the self-adaptive system. Additionally, this paper suggests a method to present and analyze service dependability by using GSN(Goal Structuring Notation) which is the existing modeling method for the presentation of assurance cases, an action mechanism adapted using an analysis result of service-dependability-cases, a methods of leveraging the service-dependability-case based self-adaptation mechanism by following the service's life cycle, and the framework architecture including the major components and the interactions between the components in the control loop of the self-adaptation process.