• 제목/요약/키워드: Continuous function

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근전도신호를 이용한 노약자/장애인용 재활 보조시스템의 인터페이스기법

  • 장영건;신철규;이은실;권장우;홍승홍
    • 대한인간공학회:학술대회논문집
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    • 대한인간공학회 1997년도 춘계학술대회논문집
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    • pp.107-113
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    • 1997
  • In this paper, an interfacing method to control rehabilitation assitance system with bio-signal is proposed. Controlling with EMG signals method has certain advantage on signal-collecting, but has some drawbacks in the function resolution of EMG signals because data-processing process is not efficient. To improve function-resolution and to increase the efficiency of EMG signal interfacing with rehabilitation assistance system, Multi-layer Perception which is highly effective with static signal and hidden-Markov model for dynamic signal resolving are fused together. In proposed method. The direction and average speed of the rehabilitation assitance system are controlled by the trajectory control and estimation of the moving direction result from the fused model. From the experiment, proposed GMM and 2-level MLP hybrid-classifier yielded 8.6% perception-error rate, improving function resolution. New acceleration control method constructed with 3 nested linear filter produced continuous acceleration paths without the information of destination point. Thus, the mass output caused by non- continuous acceleration-deceleration was eliminated. In the simulation, the necessary calculation, in the case of multiplication, was reduced by 11.54%.

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Barycentric Approximator for Reinforcement Learning Control

  • Whang Cho
    • International Journal of Precision Engineering and Manufacturing
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    • 제3권1호
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    • pp.33-42
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    • 2002
  • Recently, various experiments to apply reinforcement learning method to the self-learning intelligent control of continuous dynamic system have been reported in the machine learning related research community. The reports have produced mixed results of some successes and some failures, and show that the success of reinforcement learning method in application to the intelligent control of continuous control systems depends on the ability to combine proper function approximation method with temporal difference methods such as Q-learning and value iteration. One of the difficulties in using function approximation method in connection with temporal difference method is the absence of guarantee for the convergence of the algorithm. This paper provides a proof of convergence of a particular function approximation method based on \"barycentric interpolator\" which is known to be computationally more efficient than multilinear interpolation .

GENERALIZED SOLUTIONS OF IMPULSIVE CONTROL SYSTEMS CORRESPONDING TO CONTROLS OF BOUNDED VARIATION

  • Shin, Chang-Eon
    • 대한수학회지
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    • 제34권3호
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    • pp.581-598
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    • 1997
  • This paper is concerned with the impulsive control problem $$ \dot{x}(t) = f(t, x) + g(t, x)\dot{u}(t), t \in [0, T], x(0) = \overline{x}, $$ where u is a possibly discontinuous control function of bounded variation, $f : R \times R^n \mapsto R^n$ is a bounded and Lipschitz continuous function, and $g : R \times R^n \mapsto R^n$ is continuously differentiable w.r.t. the variable x and satisfies $\mid$g(t,\cdot) - g(s,\cdot)$\mid$ \leq \phi(t) - \phi(s)$, for some increasing function $\phi$ and every s < t. We show that the map $u \mapsto x_u$ is Lipschitz continuous when u ranges in the set of step functions whose total variations are uniformly bounded, where $x_u$ is the solution of the impulsive control system corresponding to u. We also define the generalized solution of the impulsive control system corresponding to a measurable control functin of bounded variation.

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Band engineering of bilayer graphene by metal atoms: First-principles calculations

  • Oh, D.H.;Shin, B.G.;Ahn, J.R.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.267-267
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    • 2010
  • The continuous change in the electronic band structure of metal-adsorbed bilayer graphene was calculated as a function of metal coverage using first-principles calculations. Instead of modifying the unit cell size as a function of metal coverage, the distance between the metal atoms and bilayer graphene in the same $2{\times}2$ unit unit cell was controlled to change the total charges transferred from the metal atoms to bilayer graphene. The validity of the theoretical method was confirmed by reproducing the continuous change in the electronic band structure of K-adsorbed epitaxial bilayer graphene, as shown by Ohta et al. [Science 313, 951 (2006)]. In addition, the changes in the electronic band structures of undoped, n-type, and p-type bilayer graphene were studied schematically as a function of metal coverage using the theoretical method.

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Initial Mass Function and Star Formation History in the Small Magellanic Cloud

  • Lee, Ki-Won
    • 한국지구과학회지
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    • 제35권5호
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    • pp.362-374
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    • 2014
  • This study investigated the initial mass function (IMF) and star formation history of high-mass stars in the Small Magellanic Cloud (SMC) using a population synthesis technique. We used the photometric survey catalog of Lee (2013) as the observable quantities and compare them with those of synthetic populations based on Bayesian inference. For the IMF slope (${\Gamma}$) range of -1.1 to -3.5 with steps of 0.1, five types of star formation models were tested: 1) continuous; 2) single burst at 10 Myr; 3) single burst at 60 Myr; 4) double bursts at those epochs; and 5) a complex hybrid model. In this study, a total of 125 models were tested. Based on the model calculations, it was found that the continuous model could simulate the high-mass stars of the SMC and that its IMF slope was -1.6 which is slightly steeper than Salpeter's IMF, i.e., ${\Gamma}=-1.35$.

On The Function Rings of Pointfree Topology

  • Banaschewski, Bernhard
    • Kyungpook Mathematical Journal
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    • 제48권2호
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    • pp.195-206
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    • 2008
  • The purpose of this note is to compare the rings of continuous functions, integer-valued or real-valued, in pointfree topology with those in classical topology. To this end, it first characterizes the Boolean frames (= complete Boolean algebras) whose function rings are isomorphic to a classical one and then employs this to exhibit a large class of frames for which the functions rings are not of this kind. An interesting feature of the considerations involved here is the use made of nonmeasurable cardinals. In addition, the integer-valued function rings for Boolean frames are described in terms of internal lattice-ordered ring properties.

ON ESTIMATION OF UNIFORM CONVERGENCE OF ANALYTIC FUNCTIONS BY (p, q)-BERNSTEIN OPERATORS

  • Mursaleen, M.;Khan, Faisal;Saif, Mohd;Khan, Abdul Hakim
    • Korean Journal of Mathematics
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    • 제27권2호
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    • pp.505-514
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    • 2019
  • In this paper we study the approximation properties of a continuous function by the sequence of (p, q)-Bernstein operators for q > p > 1. We obtain bounds of (p, q)-Bernstein operators. Further we prove that if a continuous function admits an analytic continuation into the disk $\{z:{\mid}z{\mid}{\leq}{\rho}\}$, then $B^n_{p,q}(g;z){\rightarrow}g(z)(n{\rightarrow}{\infty})$ uniformly on any compact set in the given disk $\{z:{\mid}z{\mid}{\leq}{\rho}\}$, ${\rho}>0$.

Extreme values of a gaussian process

  • Choi, Y.K.;Hwang, K.S.;Kang, S.B.
    • 대한수학회지
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    • 제32권4호
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    • pp.739-751
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    • 1995
  • Let ${X(t) : 0 \leq t < \infty}$ be an almost surely continuous Gaussian process with X(0) = 0, E{X(t)} = 0 and stationary increments $E{X(t) - X(s)}^2 = \sigma^2($\mid$t - s$\mid$)$, where $\sigma(y)$ is a function of $y \geq 0(e.g., if {X(t);0 \leq t < \infty}$ is a standard Wiener process, then $\sigma(t) = \sqrt{t})$. Assume that $\sigma(t), t > 0$, is a nondecreasing continuous, regularly varying function at infinity with exponent $\gamma$ for some $0 < \gamma < 1$.

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QUADRATURE METHOD FOR EQUATIONS WITH NONLINEAR BOUNDARY CONDITIONS ARISING IN A THERMAL EXPLOSION THEORY

  • Eunkyung Ko
    • East Asian mathematical journal
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    • 제39권3호
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    • pp.271-278
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    • 2023
  • We consider a 1-dimensional reaction diffusion equation with the following boundary conditions arising in a theory of the thermal explosion {-u"(t) = λf(u(t)), t ∈ (0, l), -u'(0) + C(0)u(0) = 0, u'(l) + C(l)u(l) = 0, where C : [0, ∞) → (0, ∞) is a continuous and nondecreasing function, λ > 0 is a parameter and f : [0, ∞) → (0, ∞) is a continuous function. We establish the extension of Quadrature method introduced in [8]. Using this extension, we provide numerical results for models with a typical function of f and C in a thermal explosion theory, which verify the existence, uniqueness and multiplicity results proved in [6].

Evaluation Method of Hairstyling Materials and its Application to Cosmetic Preparations

  • Abe, Hidetoshi;Iida, Ichiro;Someya, Takao
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.1-12
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    • 2003
  • Instead of sensory evaluation, we designed an evaluation method of the setting function of hairstyling products, based on an original theory focusing on changes in bending stress observed when a load with continuous bending is applied to human hair. Specifically, we developed a device to measure bending stress to quickly and objectively evaluate the condition of human hair, particularly its dynamic properties such as the setting function, following the application of hairstyling products. This device generates a load with continuous bending while applying a pendulum motion to a hair tress, one end of which is anchored. The setting function and holding power of resins of various molecular weight and ionic properties were evaluated using this device. The results demonstrated a close correlation with those obtained by experts' sensory evaluation. The evaluation results of bending stress and holding rate confirmed that the combined use of two different resins could improve the function of setting preparations. Evaluation using this device was able to substitute for sensory evaluation, and offers quick objective evaluation and detection of changes in the holding power of hairstyling products over time. We conclude that evaluation using this device is a promising new method.

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