• 제목/요약/키워드: Iterative technique

검색결과 575건 처리시간 0.029초

A MODIFIED PROXIMAL POINT ALGORITHM FOR SOLVING A CLASS OF VARIATIONAL INCLUSIONS IN BANACH SPACES

  • LIU, YING
    • Journal of applied mathematics & informatics
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    • 제33권3_4호
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    • pp.401-415
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    • 2015
  • In this paper, we propose a modified proximal point algorithm which consists of a resolvent operator technique step followed by a generalized projection onto a moving half-space for approximating a solution of a variational inclusion involving a maximal monotone mapping and a monotone, bounded and continuous operator in Banach spaces. The weak convergence of the iterative sequence generated by the algorithm is also proved.

Avoiding Indefiniteness in Criteria for Maximum Likelihood Bearing Estimation with Arbitrary Array Configuration

  • Suzuki, Masakiyo
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -3
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    • pp.1807-1810
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    • 2002
  • This paper presents a technique for avoid- ing indefiniteness in Maximum Likelihood (ML) criteria for Direction-of-Arrival (DOA) finding using a sensor ar- ray with arbitrary configuration. The ML criterion has singular points in the solution space where the criterion becomes indefinite. Solutions fly iterative techniques for ML bearing estimation may oscillate because of numerical instability which occurs due to the indefiniteness, when bearings more than one approach to the identical value. The oscillation makes the condition for terminating iterations complex. This paper proposes a technique for avoiding the indefiniteness in ML criteria.

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Model-based Predictive Control Approach to Continuous Process based on Iterative Learning Concept

  • Chin, In-Sik;Cho, Moon-Ki;Lee, Jay-H;Lee, Kwang-Soon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.41.1-41
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    • 2001
  • Since the advanced control technique such as model predictive control has been introduced to industrial plant, there have been many progresses in the process control. As a way to improve the control performance, the on-line process optimizer was integrated with the advance controller. In this study, a control technique which improves the control. As the number of changes by the optimizer is increased, the control performance of the proposed algorithm is improved. Its control performance is shown via an numerical example.

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GENERAL MIXED HARMONIC VARIATIONAL INEQUALITIES

  • Jong Kyu Kim;Avinash Lakhnotra;Tirth Ram
    • Nonlinear Functional Analysis and Applications
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    • 제29권2호
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    • pp.517-526
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    • 2024
  • In this paper, some iterative methods are used to discuss the behavior of general mixed-harmonic variational inequalities. We employ the auxiliary principle technique and g-strongly harmonic monotonicity of the operator to obtain results on the existence of solutions to a generalized class of mixed harmonic variational inequality.

BILINEAR SYSTEMS CONTROLLER DESIGN WITH APPROXIMATION TECHNIQUES

  • Lee, Sang-Hyuk;Lee, Keonhee
    • 충청수학회지
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    • 제18권1호
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    • pp.101-116
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    • 2005
  • Using the iterative method, we derive an controller realization of the bilinear system, which is resulted from the system reformulation. We utilize Banach Fixed Point Theorem to support proposed controller, and the simulation results are also illustrated to verify usefulness of this technique.

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전자계산기 프로그래밍에 있어서의 귀납적 수법에 관한 연구 (A Study on the Recursive Technique in Digital Computer Programming)

  • 임제탁
    • 전기의세계
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    • 제24권1호
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    • pp.70-74
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    • 1975
  • A model computer is designed and using this model computer it is demonstrated that computable functions are equivalent to recursive functions. It is also shown that iteratively defined computable functions can be transformed to recursively defined computable functions and that recursive programming is possible in principle, when iterative programming is possible.

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전산화단층촬영조영술에서 화질 최적화를 위한 딥러닝 기반 및 하이브리드 반복 재구성의 특성분석 (Characterization of Deep Learning-Based and Hybrid Iterative Reconstruction for Image Quality Optimization at Computer Tomography Angiography)

  • 전필현;이창래
    • 한국방사선학회논문지
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    • 제17권1호
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    • pp.1-9
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    • 2023
  • 전산화단층촬영조영술(computer tomography angiography, CTA)의 최적 화질을 위한 서로 다른 요오드 농도와 스캔 매개변수를 적용하여 필터 보정 역투영 (filtered back projection, FBP), 혼합형 반복재구성 (hybrid-iterative reconstruction, hybrid-IR) 및 딥러닝 재구성 (deep learning reconstruction, DLR)의 화질적 특성을 정량적으로 평가하였다. 320행 검출기 CT 스캐너에서 지름 19 cm의 원통형 물 팬텀 가장자리에 있는 다양한 요오드 농도 (1.2, 2.9, 4.9, 6.9, 10.4, 14.3, 18.4 및 25.9 mg/mL)의 팬텀을 스캔하였다. 각각의 재구성 기술을 사용하여 획득한 데이터는 노이즈 (noise), 변동 계수 (coefficient of variation, COV) 및 평균 제곱근 오차 (root mean square error, RMSE)을 통해 영상을 분석하였다. 요오드의 농도가 증가할수록 CT number 값은 증가하였지만 노이즈 변화는 특별한 특성을 보이지 않았다. 다양한 관전류 및 관전압에서 FBP, adaptive iterative dose reduction (AIDR) 3D 및 advanced intelligent clear-IQ engine (AiCE)에 대해 요오드 농도를 증가할수록 COV는 감소하였고 요오드 농도가 낮을 때는 재구성 기술 간의 COV 차이가 다소 발생하였지만, 요오드 농도가 높아짐에 따라 그 차이는 미약한 결과를 보였다. 또한, AiCE에서는 요오드 농도가 높아질수록 RMSE는 감소하지만 특정한 농도 (4.9 mg/mL) 이후에는 RMSE가 오히려 증가 되는 특성을 보여주었다. 따라서 최적의 CTA 영상 획득을 위해 재구성 기술에 따른 요오드 농도의 변화 및 다양한 관전류 및 관전압의 스캔 매개변수의 특성을 고려하여 환자 스캔을 해야 할 것이다.