• Title/Summary/Keyword: Semi-local convergence

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ON THE SEMI-LOCAL CONVERGENCE OF CONTRAHARMONIC-MEAN NEWTON'S METHOD (CHMN)

  • Argyros, Ioannis K.;Singh, Manoj Kumar
    • Communications of the Korean Mathematical Society
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    • v.37 no.4
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    • pp.1009-1023
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    • 2022
  • The main objective of this work is to investigate the study of the local and semi-local convergence of the contraharmonic-mean Newton's method (CHMN) for solving nonlinear equations in a Banach space. We have performed the semi-local convergence analysis by using generalized conditions. We examine the theoretical results by comparing the CHN method with the Newton's method and other third order methods by Weerakoon et al. using some test functions. The theoretical and numerical results are also supported by the basins of attraction for a selected test function.

Study on semi-supervised local constant regression estimation

  • Seok, Kyung-Ha
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.3
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    • pp.579-585
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    • 2012
  • Many different semi-supervised learning algorithms have been proposed for use wit unlabeled data. However, most of them focus on classification problems. In this paper we propose a semi-supervised regression algorithm called the semi-supervised local constant estimator (SSLCE), based on the local constant estimator (LCE), and reveal the asymptotic properties of SSLCE. We also show that the SSLCE has a faster convergence rate than that of the LCE when a well chosen weighting factor is employed. Our experiment with synthetic data shows that the SSLCE can improve performance with unlabeled data, and we recommend its use with the proper size of unlabeled data.

A MODIFIED INEXACT NEWTON METHOD

  • Huang, Pengzhan;Abduwali, Abdurishit
    • Journal of applied mathematics & informatics
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    • v.33 no.1_2
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    • pp.127-143
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    • 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.

ON THE CONVERGENCE OF NEWTON'S METHOD AND LOCALLY $H{\ddot{O}}LDERIAN$ OPERATORS

  • Argyros, Ioannis K.
    • The Pure and Applied Mathematics
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    • v.15 no.2
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    • pp.111-120
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    • 2008
  • A semi local convergence analysis is provided for Newton's method in a Banach space setting. The operators involved are only locally Holderian. We make use of a point-based approximation and center-Holderian hypotheses. This approach can be used to approximate solutions of equations involving nonsmooth operators.

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Kidney Tumor Segmentation through Semi-supervised Learning Based on Mean Teacher Using Kidney Local Guided Map in Abdominal CT Images (복부 CT 영상에서 신장 로컬 가이드 맵을 활용한 평균-교사 모델 기반의 준지도학습을 통한 신장 종양 분할)

  • Heeyoung Jeong;Hyeonjin Kim;Helen Hong
    • Journal of the Korea Computer Graphics Society
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    • v.29 no.5
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    • pp.21-30
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    • 2023
  • Accurate segmentation of the kidney tumor is necessary to identify shape, location and safety margin of tumor in abdominal CT images for surgical planning before renal partial nephrectomy. However, kidney tumor segmentation is challenging task due to the various sizes and locations of the tumor for each patient and signal intensity similarity to surrounding organs such as intestine and spleen. In this paper, we propose a semi-supervised learning-based mean teacher network that utilizes both labeled and unlabeled data using a kidney local guided map including kidney local information to segment small-sized kidney tumors occurring at various locations in the kidney, and analyze the performance according to the kidney tumor size. As a result of the study, the proposed method showed an F1-score of 75.24% by considering local information of the kidney using a kidney local guide map to locate the tumor existing around the kidney. In particular, under-segmentation of small-sized tumors which are difficult to segment was improved, and showed a 13.9%p higher F1-score even though it used a smaller amount of labeled data than nnU-Net.

ASYMPTOTIC PROPERTIES OF THE CONDITIONAL HAZARD FUNCTION ESTIMATE BY THE LOCAL LINEAR METHOD FOR FUNCTIONAL ERGODIC DATA

  • MOHAMMED BASSOUDI;ABDERRAHMANE BELGUERNA;HAMZA DAOUDI;ZEYNEB LAALA
    • Journal of applied mathematics & informatics
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    • v.41 no.6
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    • pp.1341-1364
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    • 2023
  • This article introduces a method for estimating the conditional hazard function of a real-valued response variable based on a functional variable. The method uses local linear estimation of the conditional density and cumulative distribution function and is applied to a functional stationary ergodic process where the explanatory variable is in a semi-metric space and the response is a scalar value. We also examine the uniform almost complete convergence of this estimation technique.

GENERALIZED CONDITIONS FOR THE CONVERGENCE OF INEXACT NEWTON-LIKE METHODS ON BANACH SPACES WITH A CONVERGENCE STRUCTURE AND APPLICATIONS

  • Argyros, Ioannis-K.
    • Journal of applied mathematics & informatics
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    • v.5 no.2
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    • pp.433-448
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    • 1998
  • In this study we use inexact Newton-like methods to find solutions of nonlinear operator equations on Banach spaces with a convergence structure. Our technique involves the introduction of a generalized norm as an operator from a linear space into a par-tially ordered Banach space. In this way the metric properties of the examined problem can be analyzed more precisely. Moreover this approach allows us to derive from the same theorem on the one hand semi-local results of kantorovich-type and on the other hand 2global results based on monotonicity considerations. By imposing very general Lipschitz-like conditions on the operators involved on the other hand by choosing our operators appropriately we can find sharper error bounds on the distances involved than before. Furthermore we show that special cases of our results reduce to the corresponding ones already in the literature. Finally our results are used to solve integral equations that cannot be solved with existing methods.

Mobile User Interface Pattern Clustering Using Improved Semi-Supervised Kernel Fuzzy Clustering Method

  • Jia, Wei;Hua, Qingyi;Zhang, Minjun;Chen, Rui;Ji, Xiang;Wang, Bo
    • Journal of Information Processing Systems
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    • v.15 no.4
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    • pp.986-1016
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    • 2019
  • Mobile user interface pattern (MUIP) is a kind of structured representation of interaction design knowledge. Several studies have suggested that MUIPs are a proven solution for recurring mobile interface design problems. To facilitate MUIP selection, an effective clustering method is required to discover hidden knowledge of pattern data set. In this paper, we employ the semi-supervised kernel fuzzy c-means clustering (SSKFCM) method to cluster MUIP data. In order to improve the performance of clustering, clustering parameters are optimized by utilizing the global optimization capability of particle swarm optimization (PSO) algorithm. Since the PSO algorithm is easily trapped in local optima, a novel PSO algorithm is presented in this paper. It combines an improved intuitionistic fuzzy entropy measure and a new population search strategy to enhance the population search capability and accelerate the convergence speed. Experimental results show the effectiveness and superiority of the proposed clustering method.

An Verification of the Effect of Structured Cognitive Behavioral Intervention Program for Elementary School Students with High Risk Behavior (고위험 문제행동을 보이는 초등학생을 위한 구조화된 인지행동 중재 프로그램의 효과 검증)

  • Lee, A-Reum;Song, Won-Young
    • Journal of the Korea Convergence Society
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    • v.9 no.1
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    • pp.241-251
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    • 2018
  • The study is a preliminary study of the effectiveness of the structured cognitive behavioral arbitration program targeting elementary school students who perform high risk problems based on schools for convergence with local communities. The program is designed to be practiced by semi-trained professionals. To screen high-risk students, total 102 students were tested K-CBCL and those who scored over 60T on problem behavior syndrome scale were recruited. 32 students were selected and devided into intervention group and control group. Intervention group was received 90-minutes-sessions per week, for nine weeks. The program was done by graduate students and undergraduate students majoring counseling and supervised by school psychologist. The internalization group showed significantly lower score in Internalization, anxiety/depression, and externalization group showed externalization, aggressive behavior. but mixed group didn't showed significantly lower score. Implications of the results, limitations and suggestions for future study were mentioned.

Utilizing Local Bilingual Embeddings on Korean-English Law Data (한국어-영어 법률 말뭉치의 로컬 이중 언어 임베딩)

  • Choi, Soon-Young;Matteson, Andrew Stuart;Lim, Heui-Seok
    • Journal of the Korea Convergence Society
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    • v.9 no.10
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    • pp.45-53
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    • 2018
  • Recently, studies about bilingual word embedding have been gaining much attention. However, bilingual word embedding with Korean is not actively pursued due to the difficulty in obtaining a sizable, high quality corpus. Local embeddings that can be applied to specific domains are relatively rare. Additionally, multi-word vocabulary is problematic due to the lack of one-to-one word-level correspondence in translation pairs. In this paper, we crawl 868,163 paragraphs from a Korean-English law corpus and propose three mapping strategies for word embedding. These strategies address the aforementioned issues including multi-word translation and improve translation pair quality on paragraph-aligned data. We demonstrate a twofold increase in translation pair quality compared to the global bilingual word embedding baseline.