• Title/Summary/Keyword: Implicit function

Search Result 195, Processing Time 0.023 seconds

SENSITIVITY ANALYSIS FOR A CLASS OF IMPLICIT MULTIFUNCTIONS WITH APPLICATIONS

  • Li, Shengjie;Li, Minghua
    • Bulletin of the Korean Mathematical Society
    • /
    • v.49 no.2
    • /
    • pp.249-262
    • /
    • 2012
  • In this paper, under some suitable conditions and in virtue of a selection which depends on a vector-valued function and a feasible set map, the sensitivity analysis of a class of implicit multifunctions is investigated. Moreover, by using the results established, the solution sets of parametric vector optimization problems are studied.

A Development of Task-oriented Programming System for the Application of Robot (로봇 응용을 위한 공정 지향적인 프로그래밍 시스템 개발)

  • Park, H.S.
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.13 no.4
    • /
    • pp.34-42
    • /
    • 1996
  • Robot programming has been discussed in detail during the recent years. Numerous studies in particular presented relevance, solution concepts and implementation of off-line programming. In this paper a new user-friendly robot programming method is introduced, which permits the implicit description and programming of assembly process. On the functional level of programming, the assembly processes are described in terms of their operational functions. On the language level, the individual functions are then translated into commands for the robots.

  • PDF

The Effects of Locational Point Representation of Apartment Complexes on Hedonic Valuation of Air Quality (공동주택 위치표현 방법이 대기질의 한계잠재가격 측정에 미치는 영향)

  • Chul Sohn
    • Journal of the Korean Geographical Society
    • /
    • v.38 no.6
    • /
    • pp.949-960
    • /
    • 2003
  • The marginal implicit price of air quality can be measured by taking a partial derivative of hedonic price function (HPF) with respect to the level of air quality. It has been pointed out that the size of the marginal implicit price varies with the use of different function forms, different estimation methods, and the different ways of measuring air quality level in estimating HPF. In addition to these factors, this study shows theoretically and empirically the way housing properties are represented on a digital map could differentiate the size of marginal implicit price of air quality when GIS is used to measure location attributes of the housing properties in the Korean apartment market. Furthermore, this study shows that the degree of difference in the marginal implicit price due to the manner in which housing properties are represented on a digital map can be larger than the degree of difference in the marginal implicit price due to using different function forms and estimation methods. The major implication from the results of this study is that one should carefully try diverse ways of representing housing properties in the Korean apartment market on a digital map in the process of estimating HPF, as he or she usually tries diverse function forms and estimation methods, to see if the value of the marginal implicit price of air quality varies substantially.

Improving the Subject Independent Classification of Implicit Intention By Generating Additional Training Data with PCA and ICA

  • Oh, Sang-Hoon
    • International Journal of Contents
    • /
    • v.14 no.4
    • /
    • pp.24-29
    • /
    • 2018
  • EEG-based brain-computer interfaces has focused on explicitly expressed intentions to assist physically impaired patients. For EEG-based-computer interfaces to function effectively, it should be able to understand users' implicit information. Since it is hard to gather EEG signals of human brains, we do not have enough training data which are essential for proper classification performance of implicit intention. In this paper, we improve the subject independent classification of implicit intention through the generation of additional training data. In the first stage, we perform the PCA (principal component analysis) of training data in a bid to remove redundant components in the components within the input data. After the dimension reduction by PCA, we train ICA (independent component analysis) network whose outputs are statistically independent. We can get additional training data by adding Gaussian noises to ICA outputs and projecting them to input data domain. Through simulations with EEG data provided by CNSL, KAIST, we improve the classification performance from 65.05% to 66.69% with Gamma components. The proposed sample generation method can be applied to any machine learning problem with fewer samples.

Convergence of Nonlocal Integral Operator in Peridynamics (비국부 적분 연산기로 표현되는 페리다이나믹 방정식의 수렴성)

  • Jo, Gwanghyun;Ha, Youn Doh
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.34 no.3
    • /
    • pp.151-157
    • /
    • 2021
  • This paper is devoted to a convergence study of the nonlocal integral operator in peridynamics. The implicit formulation can be an efficient approach to obtain the static/quasi-static solution of crack propagation problems. Implicit methods require constly large-matrix operations. Therefore, convergence is important for improving computational efficiency. When the radial influence function is utilized in the nonlocal integral equation, the fractional Laplacian integral equation is obtained. It has been mathematically proved that the condition number of the system matrix is affected by the order of the radial influence function and nonlocal horizon size. We formulate the static crack problem with peridynamics and utilize Newton-Raphson methods with a preconditioned conjugate gradient scheme to solve this nonlinear stationary system. The convergence behavior and the computational time for solving the implicit algebraic system have been studied with respect to the order of the radial influence function and nonlocal horizon size.

MERIT FUNCTIONS FOR MATRIX CONE COMPLEMENTARITY PROBLEMS

  • Wang, Li;Liu, Yong-Jin;Jiang, Yong
    • Journal of applied mathematics & informatics
    • /
    • v.31 no.5_6
    • /
    • pp.795-812
    • /
    • 2013
  • The merit function arises from the development of the solution methods for the complementarity problems defined over the cone of non negative real vectors and has been well extended to the complementarity problems defined over the symmetric cones. In this paper, we focus on the extension of the merit functions including the gap function, the regularized gap function, the implicit Lagrangian and others to the complementarity problems defined over the nonsymmetric matrix cone. These theoretical results of this paper suggest new solution methods based on unconstrained and/or simply constrained methods to solve the matrix cone complementarity problems (MCCP).

Multicut high dimensional model representation for reliability analysis

  • Chowdhury, Rajib;Rao, B.N.
    • Structural Engineering and Mechanics
    • /
    • v.38 no.5
    • /
    • pp.651-674
    • /
    • 2011
  • This paper presents a novel method for predicting the failure probability of structural or mechanical systems subjected to random loads and material properties involving multiple design points. The method involves Multicut High Dimensional Model Representation (Multicut-HDMR) technique in conjunction with moving least squares to approximate the original implicit limit state/performance function with an explicit function. Depending on the order chosen sometimes truncated Cut-HDMR expansion is unable to approximate the original implicit limit state/performance function when multiple design points exist on the limit state/performance function or when the problem domain is large. Multicut-HDMR addresses this problem by using multiple reference points to improve accuracy of the approximate limit state/performance function. Numerical examples show the accuracy and efficiency of the proposed approach in estimating the failure probability.

Turbulent Flow Calculations Using an Unstructured Hybrid Meshes (2차원 혼합격자를 이용한 난류유동 계산)

  • Kim J. S.;Oh W. S.;Kwon O. J.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 1999.05a
    • /
    • pp.90-97
    • /
    • 1999
  • An implicit turbulent flow solver is developed for 2-D unstructured hybrid meshes. Spatial discretization is accomplished by a cell-centered finite volume formulation using an upwind flux differencing. Time is advanced by an implicit backward Euler time stepping scheme. Flow turbulence effects are modeled by the Spalart-Allmaras one equation model, which is coupled with wall function. The numerical method is applied for flows on a flat plate, the NACA 0012 airfoil, and the Douglas 3 element airfoil. The results are compared with experimental data.

  • PDF

Neurobiological Mechanism of Psychotherapy (정신치료의 신경생물학적 기전)

  • Lee, Seung-Hwan;Kim, Seung-Hyun
    • Korean Journal of Biological Psychiatry
    • /
    • v.9 no.2
    • /
    • pp.79-94
    • /
    • 2002
  • Polarisation of biological and psychosocial aspects of psychiatry is nowadays main stream. Current knowledges of the interaction between biology and psychology make it possible to consider a truly integrative approach of the two aspects. Research findings suggest that the neuronal plasticity is the key mechanism to answer how the mental function work to an environmental stimuli and how the psychotherapeutic approach work on the brain. Advances in neuroscience research have led to a more sophisticated understanding of how psychotherapy may affect brain function. Even though there have been a tremendous efforts to find out the neurobiological mechanism of mental function, the answer is at best premature. In this article, research findings about of neuronal plasticity, implicit memory, animal studies which were associated with psychotherapy and psychological aspects were reviewed.

  • PDF

Implicit Learning with Artificial Grammar : Simulations using EPAM IV (인공 문법을 사용한 암묵 학습: EPAM IV를 사용한 모사)

  • 정혜선
    • Korean Journal of Cognitive Science
    • /
    • v.14 no.1
    • /
    • pp.1-9
    • /
    • 2003
  • In implicit learning tasks, human participants learn grammatical letter strings better than random letter strings. After learning grammatical letter strings, participants were able to judge the grammaticality of new letter strings that they have never seen before. EPAM (Elementary Perceiver and Memorizer) IV, a rote learner without any rule abstraction mechanism, was used to simulate these results. The results showed that EPAM IV with a within-item chunking function was able to learn grammatical letter strings better than random letter strings and discriminate grammatical letter strings from non-grammatical letter strings. The success of EPAM IV in simulating human performance strongly indicated that recognition memory based on chunking plays a critical role in implicit learning.

  • PDF