• Title/Summary/Keyword: Lipschitz Continuity

Search Result 46, Processing Time 0.025 seconds

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.

Technique Proposal to Stabilize Lipschitz Continuity of WGAN Based on Regularization Terms (정칙화 항에 기반한 WGAN의 립쉬츠 연속 안정화 기법 제안)

  • Hahn, Hee-Il
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.20 no.1
    • /
    • pp.239-246
    • /
    • 2020
  • The recently proposed Wasserstein generative adversarial network (WGAN) has improved some of the tricky and unstable training processes that are chronic problems of the generative adversarial network(GAN), but there are still cases where it generates poor samples or fails to converge. In order to solve the problems, this paper proposes algorithms to improve the sampling process so that the discriminator can more accurately estimate the data probability distribution to be modeled and to stably maintain the discriminator should be Lipschitz continuous. Through various experiments, we analyze the characteristics of the proposed techniques and verify their performances.

Approximate Controllability for Semilinear Neutral Differential Systems in Hilbert Spaces

  • Jeong, Jin-Mun;Park, Ah-Ran;Son, Sang-Jin
    • Kyungpook Mathematical Journal
    • /
    • v.61 no.3
    • /
    • pp.559-581
    • /
    • 2021
  • In this paper, we establish the existence of solutions and the approximate controllability for the semilinear neutral differential control system under natural assumptions such as the local Lipschitz continuity of nonlinear term. First, we deal with the regularity of solutions of the neutral control system using fractional powers of operators. We also consider the approximate controllability for the semilinear neutral control equation, with a control part in place of a forcing term, using conditions for the range of the controller without the inequality condition as in previous results.

GENERALIZED PROXIMAL ITERATIVELY REWEIGHTED ℓ1 ALGORITHM WITH CO-COERCIVENESS FOR NONSMOOTH AND NONCONVEX MINIMIZATION PROBLEM

  • Myeongmin Kang
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.37 no.1
    • /
    • pp.41-55
    • /
    • 2024
  • The nonconvex and nonsmooth optimization problem has been widely applicable in image processing and machine learning. In this paper, we propose an extension of the proximal iteratively reweighted ℓ1 algorithm for nonconvex and nonsmooth minmization problem. We assume the co-coerciveness of a term of objective function instead of Lipschitz gradient condition, which is generalized property of Lipschitz continuity. We prove the global convergence of the proposed algorithm. Numerical results show that the proposed algorithm converges faster than original proximal iteratively reweighed algorithm and existing algorithms.

SENSITIVITY ANALYSIS FOR SYSTEM OF PARAMETRIC GENERALIZED QUASI-VARIATIONAL INCLUSIONS INVOLVING R-ACCRETIVE MAPPINGS

  • Kazmi, Kaleem Raza;Khan, Faizan Ahmad;Ahmad, Naeem
    • Journal of the Korean Mathematical Society
    • /
    • v.46 no.6
    • /
    • pp.1319-1338
    • /
    • 2009
  • In this paper, using proximal-point mappings technique of Raccretive mappings and the property of the fixed point set of set-valued contractive mappings, we study the behavior and sensitivity analysis of the solution set of the system of parametric generalized quasi-variational inclusions involving R-accretive mappings in real uniformly smooth Banach space. Further under suitable conditions, we discuss the Lipschitz continuity of the solution set with respect to parameters. The technique and results presented in this paper can be viewed as extension of the techniques and corresponding results given in [3, 23, 24, 32, 33, 34].

COMMON FIXED POINTS UNDER LIPSCHITZ TYPE CONDITION

  • Pant, Vyomesh
    • Bulletin of the Korean Mathematical Society
    • /
    • v.45 no.3
    • /
    • pp.467-475
    • /
    • 2008
  • The aim of the present paper is three fold. Firstly, we obtain common fixed point theorems for a pair of selfmaps satisfying nonexpansive or Lipschitz type condition by using the notion of pointwise R-weak commutativity but without assuming the completeness of the space or continuity of the mappings involved (Theorem 1, Theorem 2 and Theorem 3). Secondly, we generalize the results obtained in first three theorems for four mappings by replacing the condition of noncompatibility of maps with the property (E.A) and using the R-weak commutativity of type $(A_g)$ (Theorem 4). Thirdly, in Theorem 5, we show that if the aspect of noncompatibility is taken in place of the property (E.A), the maps become discontinuous at their common fixed point. We, thus, provide one more answer to the problem posed by Rhoades [11] regarding the existence of contractive definition which is strong enough to generate fixed point but does not forces the maps to become continuous.

ON STRONG CONVERGENCE THEOREMS FOR A VISCOSITY-TYPE TSENG'S EXTRAGRADIENT METHODS SOLVING QUASIMONOTONE VARIATIONAL INEQUALITIES

  • Wairojjana, Nopparat;Pholasa, Nattawut;Pakkaranang, Nuttapol
    • Nonlinear Functional Analysis and Applications
    • /
    • v.27 no.2
    • /
    • pp.381-403
    • /
    • 2022
  • The main goal of this research is to solve variational inequalities involving quasimonotone operators in infinite-dimensional real Hilbert spaces numerically. The main advantage of these iterative schemes is the ease with which step size rules can be designed based on an operator explanation rather than the Lipschitz constant or another line search method. The proposed iterative schemes use a monotone and non-monotone step size strategy based on mapping (operator) knowledge as a replacement for the Lipschitz constant or another line search method. The strong convergences have been demonstrated to correspond well to the proposed methods and to settle certain control specification conditions. Finally, we propose some numerical experiments to assess the effectiveness and influence of iterative methods.

APPROXIMATION BY GENUINE LUPAŞ-BETA-STANCU OPERATORS

  • KUMAR, ALOK;VANDANA, VANDANA
    • Journal of applied mathematics & informatics
    • /
    • v.36 no.1_2
    • /
    • pp.15-28
    • /
    • 2018
  • In this paper, we introduce a Stancu type generalization of genuine LupaŞ-Beta operators of integral type. We establish some moment estimates and the direct results in terms of classical modulus of continuity, Voronovskaja-type asymptotic theorem, weighted approximation, rate of convergence and pointwise estimates using the Lipschitz type maximal function. Lastly, we propose a king type modification of these operators to obtain better estimates.

ON STATISTICAL APPROXIMATION PROPERTIES OF MODIFIED q-BERNSTEIN-SCHURER OPERATORS

  • Ren, Mei-Ying;Zeng, Xiao-Ming
    • Bulletin of the Korean Mathematical Society
    • /
    • v.50 no.4
    • /
    • pp.1145-1156
    • /
    • 2013
  • In this paper, a kind of modified $q$-Bernstein-Schurer operators is introduced. The Korovkin type statistical approximation property of these operators is investigated. Then the rates of statistical convergence of these operators are also studied by means of modulus of continuity and the help of functions of the Lipschitz class. Furthermore, a Voronovskaja type result for these operators is given.

BOUNDEDNESS AND CONTINUITY OF SOLUTIONS FOR STOCHASTIC DIFFERENTIAL INCLUSIONS ON INFINITE DIMENSIONAL SPACE

  • Yun, Yong-Sik;Ryu, Sang-Uk
    • Bulletin of the Korean Mathematical Society
    • /
    • v.44 no.4
    • /
    • pp.807-816
    • /
    • 2007
  • For the stochastic differential inclusion on infinite dimensional space of the form $dX_t{\in}\sigma(X_t)dW_t+b(X_t)dt$, where ${\sigma}$, b are set-valued maps, W is an infinite dimensional Hilbert space valued Q-Wiener process, we prove the boundedness and continuity of solutions under the assumption that ${\sigma}$ and b are closed convex set-valued satisfying the Lipschitz property using approximation.