• Title/Summary/Keyword: decay function

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A Study on Automatic Learning of Weight Decay Neural Network (가중치감소 신경망의 자동학습에 관한 연구)

  • Hwang, Chang-Ha;Na, Eun-Young;Seok, Kyung-Ha
    • Journal of the Korean Data and Information Science Society
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    • v.12 no.2
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    • pp.1-10
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    • 2001
  • Neural networks we increasingly being seen as an addition to the statistics toolkit which should be considered alongside both classical and modern statistical methods. Neural networks are usually useful for classification and function estimation. In this paper we concentrate on function estimation using neural networks with weight decay factor The use of weight decay seems both to help the optimization process and to avoid overfitting. In this type of neural networks, the problem to decide the number of hidden nodes, weight decay parameter and iteration number of learning is very important. It is called the optimization of weight decay neural networks. In this paper we propose a automatic optimization based on genetic algorithms. Moreover, we compare the weight decay neural network automatically learned according to automatic optimization with ordinary neural network, projection pursuit regression and support vector machines.

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EXPONENTIAL DECAY FOR THE SOLUTION OF THE VISCOELASTIC KIRCHHOFF TYPE EQUATION WITH MEMORY CONDITION AT THE BOUNDARY

  • Kim, Daewook
    • East Asian mathematical journal
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    • v.34 no.1
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    • pp.69-84
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    • 2018
  • In this paper, we study the viscoelastic Kirchhoff type equation with a nonlinear source for each independent kernels h and g with respect to Volterra terms. Under the smallness condition with respect to Kirchhoff coefficient and the relaxation function and other assumptions, we prove the uniform decay rate of the Kirchhoff type energy.

GENERAL DECAY OF SOLUTIONS OF NONLINEAR VISCOELASTIC WAVE EQUATION

  • Shin, Kiyeon;Kang, Sujin
    • East Asian mathematical journal
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    • v.32 no.5
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    • pp.651-658
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    • 2016
  • In a bounded domain, we consider $$u_{tt}-{\Delta}u+{\normalsize\displaystyle\smashmargin{2}{\int\nolimits_0}^t}\;g(t-{\tau}){\Delta}ud{\tau}+u_t={\mid}u{\mid}^pu$$, where p > 0 and g is a nonnegative and decaying function. We establish a general decay result which is not necessarily of exponential or polynomial type.

Analysis of Complex Forced Raleigh Scattering Decay Profiles for the Diffusion of Methyl Yellow in Binary Solution

  • 박하선;성정문;이현정;장태현;Daniel R. Spiegal
    • Bulletin of the Korean Chemical Society
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    • v.18 no.9
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    • pp.1006-1010
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    • 1997
  • The nature and analysis methods of complicated decay profiles found in forced Rayleigh scattering (FRS) have been investigated for the probe diffusion of methyl yellow in 2-propanol. The complementary shifted and ground state grating effect, which is known to be the origin of non-single exponential decays, was analyzed by non-linear regression fitting to a double exponential model function. We confirmed that the parameters were highly correlated so that it was difficult to extract a unique set of parameters in the presence of experimental noise. Nevertheless, a reasonable range of decay time constants could be estimated from the grating spacing dependence.

Eu(Ⅲ) Luminescence Phase-Modulation Spectroscopy as a Site-Selective Probe of Y Zeolite

  • 황한신;이선배;장두전
    • Bulletin of the Korean Chemical Society
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    • v.19 no.4
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    • pp.471-475
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    • 1998
  • Phase shift spectroscopy is applied to Eu(Ⅲ) luminescence from $Eu^{3+}$-exchanged Y zeolite. The phase shift and intensity modulation of luminescence following intensity-modulated excitation are measured as a function of modulation frequency and they are fitted into a double exponential decay. The fast decay component, compared with the slow one, has narrower spectral bandwidth and is emitted from the $Eu^{3+}$ that has more polar and definite environment with higher symmetry and that interacts more easily with hydrated water molecules. The fast decay component is attributed to $Eu^{3+}$ at site Ⅱ' while the slow one to $Eu^{3+}$ at sites Ⅰ' and Ⅰ.

EXISTENCE AND GENERAL DECAY FOR A VISCOELASTIC EQUATION WITH LOGARITHMIC NONLINEARITY

  • Ha, Tae Gab;Park, Sun-Hye
    • Journal of the Korean Mathematical Society
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    • v.58 no.6
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    • pp.1433-1448
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    • 2021
  • In the present work, we investigate a viscoelastic equation involving a logarithmic nonlinear source term. After proving the existence of solutions, we establish a general decay estimate of the solution using energy estimates and theory of convex functions. This result extends and complements some previous results of [9, 21].

Mathematical Programming and Optimization of the Resource Allocation and Deployment for Disaster Response : AED case study (수리계획법을 활용한 방재자원 배치 최적화: AED 배치 사례)

  • Hwang, Seongeun;Lee, Nagyeong;Jang, Dongkuk;Shin, Dongil
    • Journal of the Korean Institute of Gas
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    • v.25 no.3
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    • pp.53-58
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    • 2021
  • The number of patients with cardiovascular diseases who experience an out-of-hospital cardiac arrest (OHCA) are increasing among young adults as well as the aged population. An automated external defibrillator (AED) is vital in improving survival rates of OHCA victims. Survival rates of OHCA were shown to decline exponentially in time to defibrillation, yet studies in Korea are uncommon that captures the properties of their survival rates in examining optimal locations of AEDs. In this study, we worked on the maximal gradual coverage location problem (MGCLP) with exponential decay coverage function to decide on their optimal locations. The exponential decay coverage function mitigates the drawback of over-estimating survival rates of OHCA patients. It is expected that a more sophisticated facility location problem will be developed to identify the "emergent" characteristics of pedestrians who responds to the OHCA occurrence by incorporating random pedestrian locations and movement through simulation.

ENERGY DECAY FOR A VISCOELASTIC EQUATION WITH BALAKRISHNAN-TAYLOR DAMPING INVOLVING INFINITE MEMORY AND NONLINEAR TIME-VARYING DELAY TERMS IN DYNAMICAL BOUNDARY

  • Soufiane Benkouider;Abita Rahmoune
    • Communications of the Korean Mathematical Society
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    • v.38 no.3
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    • pp.943-966
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    • 2023
  • In this paper, we study the initial-boundary value problem for viscoelastic wave equations of Kirchhoff type with Balakrishnan-Taylor damping terms in the presence of the infinite memory and external time-varying delay. For a certain class of relaxation functions and certain initial data, we prove that the decay rate of the solution energy is similar to that of relaxation function which is not necessarily of exponential or polynomial type. Also, we show another stability with g satisfying some general growth at infinity.

Application of the Projection Operator Technique to the Study of NMR Line Shape and Free Induction Decay Curve (NMR 吸收線 모양과 誘導磁氣自由減衰曲線 硏究에의 投影演算子法의 應用)

  • Lee Jo W.;Sung Nak Jun
    • Journal of the Korean Chemical Society
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    • v.21 no.5
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    • pp.362-371
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    • 1977
  • In this paper application of the projection operator technique to the study of NMR absorption line shape and free induction decay curve is explored. It is found that the projection operator technique can provide a convenient means for deriving a set of hierarchy equations which may serve as a good starting point for theoretical calculation of the absorption line and free induction decay function by successive approximation or by an appropriate decoupling approximation. A brief review of linear response theory of NMR line shape and the relation between the absorption line shape and free induction decay function are also described.

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A new function of glucocorticoid receptor: regulation of mRNA stability

  • Park, Ok Hyun;Do, Eunjin;Kim, Yoon Ki
    • BMB Reports
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    • v.48 no.7
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    • pp.367-368
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    • 2015
  • It has long been thought that glucocorticoid receptor (GR) functions as a DNA-binding transcription factor in response to its ligand (a glucocorticoid) and thus regulates various cellular and physiological processes. It is also known that GR can bind not only to DNA but also to mRNA; this observation points to the possible role of GR in mRNA metabolism. Recent data revealed a molecular mechanism by which binding of GR to target mRNA elicits rapid mRNA degradation. GR binds to specific RNA sequences regardless of the presence of a ligand. In the presence of a ligand, however, the mRNA-associated GR can recruit PNRC2 and UPF1, both of which are specific factors involved in nonsense-mediated mRNA decay (NMD). PNRC2 then recruits the decapping complex, consequently promoting mRNA degradation. This mode of mRNA decay is termed "GR-mediated mRNA decay" (GMD). Further research demonstrated that GMD plays a critical role in chemotaxis of immune cells by targeting CCL2 mRNA. All these observations provide molecular insights into a previously unappreciated function of GR in posttranscriptional regulation of gene expression. [BMB Reports 2015; 48(7): 367-368]