• Title/Summary/Keyword: local convergence

Search Result 1,547, Processing Time 0.03 seconds

Derivative Evaluation and Conditional Random Selection for Accelerating Genetic Algorithms

  • Jung, Sung-Hoon
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.5 no.1
    • /
    • pp.21-28
    • /
    • 2005
  • This paper proposes a new method for accelerating the search speed of genetic algorithms by taking derivative evaluation and conditional random selection into account in their evolution process. Derivative evaluation makes genetic algorithms focus on the individuals whose fitness is rapidly increased. This accelerates the search speed of genetic algorithms by enhancing exploitation like steepest descent methods but also increases the possibility of a premature convergence that means most individuals after a few generations approach to local optima. On the other hand, derivative evaluation under a premature convergence helps genetic algorithms escape the local optima by enhancing exploration. If GAs fall into a premature convergence, random selection is used in order to help escaping local optimum, but its effects are not large. We experimented our method with one combinatorial problem and five complex function optimization problems. Experimental results showed that our method was superior to the simple genetic algorithm especially when the search space is large.

ON A LOCAL CHARACTERIZATION OF SOME NEWTON-LIKE METHODS OF R-ORDER AT LEAST THREE UNDER WEAK CONDITIONS IN BANACH SPACES

  • Argyros, Ioannis K.;George, Santhosh
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.28 no.4
    • /
    • pp.513-523
    • /
    • 2015
  • We present a local convergence analysis of some Newton-like methods of R-order at least three in order to approximate a solution of a nonlinear equation in a Banach space. Our sufficient convergence conditions involve only hypotheses on the first and second $Fr{\acute{e}}chet$-derivative of the operator involved. These conditions are weaker that the corresponding ones given by Hernandez, Romero [10] and others [1], [4]-[9] requiring hypotheses up to the third $Fr{\acute{e}}chet$ derivative. Numerical examples are also provided in this study.

NEWTON SCHULZ METHOD FOR SOLVING NONLINEAR MATRIX EQUATION Xp + AXA = Q

  • Kim, Hyun-Min;Kim, Young-jin;Meng, Jie
    • Journal of the Korean Mathematical Society
    • /
    • v.55 no.6
    • /
    • pp.1529-1540
    • /
    • 2018
  • The matrix equation $X^p+A^*XA=Q$ has been studied to find the positive definite solution in several researches. In this paper, we consider fixed-point iteration and Newton's method for finding the matrix p-th root. From these two considerations, we will use the Newton-Schulz algorithm (N.S.A). We will show the residual relation and the local convergence of the fixed-point iteration. The local convergence guarantees the convergence of N.S.A. We also show numerical experiments and easily check that the N.S. algorithm reduce the CPU-time significantly.

Iterative Adaptive Hybrid Image Restoration for Fast Convergence (하이브리드 고속 영상 복원 방식)

  • Ko, Kyel;Hong, Min-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.35 no.9C
    • /
    • pp.743-747
    • /
    • 2010
  • This paper presents an iterative adaptive hybrid image restoration algorithm for fast convergence. The local variance, mean, and maximum value are used to constrain the solution space. These parameters are computed at each iteration step using partially restored image at each iteration, and they are used to impose the degree of local smoothness on the solution. The resulting iterative algorithm exhibits increased convergence speed and better performance than typical regularized constrained least squares (RCLS) approach.

Relationship between Job Burden, Job Stress Coping Level and Job Satisfaction of Nurses at Local Hub Hospital in the COVID-19 Situation (COVID-19 상황에서 지역거점병원 간호사의 직무부담감, 직무스트레스 대처수준과 직무만족도와의 관계)

  • Kim, Kyeong-Ah
    • Journal of the Korea Convergence Society
    • /
    • v.13 no.1
    • /
    • pp.489-498
    • /
    • 2022
  • This study was conducted to identify factors that affect the job satisfaction of nurses at local hub hospital in the COVID-19 situation. Data were collected from 230 nurses working at 4 local hub hospital in C-do through a questionnaire. Using SPSS/WIN statistics 25.0, the data was analyzed by t-test, ANOVA, Pearson Correlation, and Multiple Linear Regression. Factors that were significant to the job satisfaction of nurses at local hub hospital were self-efficacy(t=3.003, p=.003), G local hub hospital(t=2.739, p=.007), and job burden(t=-4.291, p<.001) which showed 44.1% of the explanation. In conclusion, in order to increase job satisfaction of nurses at local hub hospitals in the COVID-19 situation, it is necessary to develop a convergence program that improves self-efficacy, and policy support is needed to lower the job burden.

General Local Transformer Network in Weakly-supervised Point Cloud Analysis (약간 감독되는 포인트 클라우드 분석에서 일반 로컬 트랜스포머 네트워크)

  • Anh-Thuan Tran;Tae Ho Lee;Hoanh-Su Le;Philjoo Choi;Suk-Hwan Lee;Ki-Ryong Kwon
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2023.11a
    • /
    • pp.528-529
    • /
    • 2023
  • Due to vast points and irregular structure, labeling full points in large-scale point clouds is highly tedious and time-consuming. To resolve this issue, we propose a novel point-based transformer network in weakly-supervised semantic segmentation, which only needs 0.1% point annotations. Our network introduces general local features, representing global factors from different neighborhoods based on their order positions. Then, we share query point weights to local features through point attention to reinforce impacts, which are essential in determining sparse point labels. Geometric encoding is introduced to balance query point impact and remind point position during training. As a result, one point in specific local areas can obtain global features from corresponding ones in other neighborhoods and reinforce from its query points. Experimental results on benchmark large-scale point clouds demonstrate our proposed network's state-of-the-art performance.

A MODIFIED INEXACT NEWTON METHOD

  • Huang, Pengzhan;Abduwali, Abdurishit
    • Journal of applied mathematics & informatics
    • /
    • v.33 no.1_2
    • /
    • pp.127-143
    • /
    • 2015
  • In this paper, we consider a modified inexact Newton method for solving a nonlinear system F(x) = 0 where $F(x):R^n{\rightarrow}R^n$. The basic idea is to accelerate convergence. A semi-local convergence theorem for the modified inexact Newton method is established and an affine invariant version is also given. Moreover, we test three numerical examples which show that the modified inexact scheme is more efficient than the classical inexact Newton strategy.

A Study on Local Micro Pattern for Facial Expression Recognition (얼굴 표정 인식을 위한 지역 미세 패턴 기술에 관한 연구)

  • Jung, Woong Kyung;Cho, Young Tak;Ahn, Yong Hak;Chae, Ok Sam
    • Convergence Security Journal
    • /
    • v.14 no.5
    • /
    • pp.17-24
    • /
    • 2014
  • This study proposed LDP (Local Directional Pattern) as a new local micro pattern for facial expression recognition to solve noise sensitive problem of LBP (Local Binary Pattern). The proposed method extracts 8-directional components using $m{\times}m$ mask to solve LBP's problem and choose biggest k components, each chosen component marked with 1 as a bit, otherwise 0. Finally, generates a pattern code with bit sequence as 8-directional components. The result shows better performance of rotation and noise adaptation. Also, a new local facial feature can be developed to present both PFF (permanent Facial Feature) and TFF (Transient Facial Feature) based on the proposed method.

WEAK SUFFICIENT CONVERGENCE CONDITIONS AND APPLICATIONS FOR NEWTON METHODS

  • Argyros, Ioannis-K.
    • Journal of applied mathematics & informatics
    • /
    • v.16 no.1_2
    • /
    • pp.1-17
    • /
    • 2004
  • The famous Newton-Kantorovich hypothesis has been used for a long time as a sufficient condition for the convergence of Newton method to a solution of an equation in connection with the Lipschitz continuity of the Frechet-derivative of the operator involved. Using Lipschitz and center-Lipschitz conditions we show that the Newton-Kantorovich hypothesis is weakened. The error bounds obtained under our semilocal convergence result are finer and the information on the location of the solution more precise than the corresponding ones given by the dominating Newton-Kantorovich theorem, and under the same hypotheses/computational cost, since the evaluation of the Lipschitz also requires the evaluation of the center-Lipschitz constant. In the case of local convergence we obtain a larger convergence radius than before. This observation is important in computational mathematics and can be used in connection to projection methods and in the construction of optimum mesh independence refinement strategies.

A Study on the Local Cultures Design Using New Media (뉴미디어를 활용한 지역문화디자인 연구)

  • Lee, Hyun-Woo;Kim, Byung-Ok
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2012.10a
    • /
    • pp.469-472
    • /
    • 2012
  • This Paper studied out prototype and the structure of Convergence on Cultures Industry and started with issues based on Local Cultures Design in New Media. platform with the New Media have the information that aims to develop relationships with Local Culture. In a world where the paradigm is changing the Convergence of all ages, transcending national borders in the mediator role of modern could have been important. Under this Situation, this study has a significant meaning because it proves that the Local Cultures Design in Degital Contents is analyzed by New Media.

  • PDF