• Title, Summary, Keyword: Decay Function

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Wavelet Estimation of Regression Functions with Errors in Variables

  • Kim, Woo-Chul;Koo, Ja-Yong
    • Communications for Statistical Applications and Methods
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    • v.6 no.3
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    • pp.849-860
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    • 1999
  • This paper addresses the issue of estimating regression function with errors in variables using wavelets. We adopt a nonparametric approach in assuming that the regression function has no specific parametric form, To account for errors in covariates deconvolution is involved in the construction of a new class of linear wavelet estimators. using the wavelet characterization of Besov spaces the question of regression estimation with Besov constraint can be reduced to a problem in a space of sequences. Rates of convergence are studied over Besov function classes $B_{spq}$ using $L_2$ error measure. It is shown that the rates of convergence depend on the smoothness s of the regression function and the decay rate of characteristic function of the contaminating error.

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Development of Radiation Free Soft X-Ray Ionizer with Ion Control (완전차폐 및 이온조절형 연X선식 정전기제거장치의 개발)

  • Jeong, Phil Hoon;Lee, Dong Hoon
    • Journal of the Korean Society of Safety
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    • v.31 no.5
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    • pp.22-27
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    • 2016
  • The Electrostatic Charge Prevention Technology is a core factor that highly influences the yield of Ultra High Resolution Flat Panel Display and high-integrated semiconductor manufacturing processes. The corona or x-ray ionizations are commonly used in order to eliminate static charges during manufacturing processes. To develop such a revolutionary x-ray ionizer that is free of x-ray radiation and has function to control the volume of ion formation simultaneously is a goal of this research and it absolutely overcomes the current risks of x-ray ionization. Under the International Commission on Radiological Protection, it must have a leakage radiation level that should be lower than a recommended level that is $1{\mu}Sv/hour$. In this research, the new generation of x-ray ionizer can easily control both the volume of ion formation and the leakage radiation level at the same time. In the research, the test constraints were set and the descriptions are as below; First, In order not to leak x-ray radiation while testing, the shielding box was fully installed around the test equipment area. Second, Implement the metallic Ring Electrode along a tube window and applied zero to ${\pm}8kV$ with respect to manage the positive and negative ions formation. Lastly, the ion duty ratio was able to be controlled in different test set-ups along with a free x-ray leakage through the metallic Ring Electrode. In the result of experiment, the maximum x-ray radiation leakage was $0.2{\mu}Sv/h$. These outcome is lower than the ICRP 103 recommended value, which is $1{\mu}Sv/h$. When applying voltage to the metallic ring electrode, the positive decay time was 2.18s at the distance of 300 mm and its slope was 0.272. In addition, the negative decay time was 2.1s at the distance of 300 mm and its slope was 0.262. At the distance of 200 mm, the positive decay time was 2.29s and its slope was 0.286. The negative decay time was 2.35s and its slope was 0.293. At the distance of 100 mm, the positive decay time was 2.71s and its slope was 0.338. The negative decay time was 3.07s and its slope was 0.383. According to these research, the observation was shown that these new concept of ionizer is able to minimize the leakage radiation level and to control the positive and negative ion duty ratio while ionization.

Modeling of Time Delay Systems using Exponential Analysis Method

  • Iwai, Zenta;Mizumoto, Ikuro;Kumon, Makoto;Torigoe, Ippei
    • 제어로봇시스템학회:학술대회논문집
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    • pp.2298-2303
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    • 2003
  • In this paper, very simple methods based on the exponential analysis are presented by which transfer function models for processes can easily be obtained. These methods employ step responses or impulse responses of the processes. These can also give a more precise transfer function model compared to the well-known graphical methods. Transfer functions are determined based on Prony method, which is one of the oldest and the most representative methods in the exponential analysis. Here, the method is reformed and applied to obtain the so-called low-order transfer function with pure time delay from the data of the step response. The effectiveness of the proposed method is examined through several numerical examples and experiments of the 2-tank level control process.

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Molecular Dynamics Simulation Studies of a Model System for Liquid Crystals Consisting of Rodlike Molecules in NPT Ensemble

  • Lee, Chang Jun;Sim, Hun Gu;Kim, Un Chun;Lee, Song Hui;Park, Hyeong Suk
    • Bulletin of the Korean Chemical Society
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    • v.21 no.3
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    • pp.310-316
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    • 2000
  • Molecular dynamics simulation studies for thermotropic liquid crystalline systems conposed of rodlike molecules with 6 Lennard-Jones interaction sites wre performed in NPT ensemble. Within the range of temperature studied, the system exhibited isotropic and smectic phase. For the characterization of the smectic phase, we examined the structure of the liquid crystalline phase via the radial distribution function, its longitudinal and transverse components to the director, and other orientational correlation function, its longitudinal and transverse components to the director, and other orientational correlation functions. In the smectic A phase, our results showed a large anisotropy in translational motion (i.e.,$D_⊥ >> D_∥$), and the decay of the collective orientational correlation function of rank two became slower than that of the single particle orientational correlation function of rank one. Comments on the spontaneous growth of orientational order directly from the isotropic phase are given.

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Measuring Benefits of Providing Water for Environmental Improvement in Yeongdok Ohsip River: Considering Protest Bids and Distance-Decay Function in the Application of CVM (영덕오십천 환경개선용수 공급의 경제적 편익측정: CVM 적용에 있어 저항응답의 처리와 거리소멸함수)

  • Eom, Young Sook
    • Environmental and Resource Economics Review
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    • v.24 no.2
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    • pp.435-461
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    • 2015
  • Recently, Korean development Institute includes water for environmental improvement as an additional water demand category in water resources development project. In response to this change, this paper is to measure benefits of providing additional water in Yeondok Ohsip River by applying contingent valuation method. This study extended the conventional CVM design by incorporating distance variable into WTP function of dichotonomous choice responses and treated protest bids by estimating sample-selection models. The empirical analysis exhibited that more than 30% of respondents were categorized as protest bids and the mean of WTP from sample selection models were three times higher than that of the whole sample. In addition, the distance variable had significantly negative impact on sample WTP regardless of variables forms, and the geographical market area were more 400km, which implies that beneficiaries of water service would the households from the whole nation.

Quantitative Aspects of 2D Carbon-13 INADEQUATE Experiment of Organic Molecules (유기화합물의 구조분석에서 2D Carbon-13 INADEQUATE 실험의 정량적 고찰)

  • Lee, Sueg-Geun
    • Analytical Science and Technology
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    • v.13 no.4
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    • pp.539-543
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    • 2000
  • The quantitative aspects of 2D carbon-13 INADEQUATE (Incredible Natural Abundance DoublE QUAntum Transfer Experiment) experiment were studied on the basis of the time needed in various concentrations of samples. In order to evaluate the quantitative time of this experiment, eight compounds were selected (M. W. ca. 150-500). The effect on time needed of various concentrations showed exponential decay function, Y=$8.15X^{-0.64}$.

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Excitation energy transfer from carotenoids probed by femtosecond time-resolved fluorescence spectroscopy

  • Akimoto, Seiji;Yamazaki, Iwao;Mimuro, Mamoru
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.78-81
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    • 2002
  • Fluorescence rise and decay curves of carotenoids were measured in solutions and in pigment protein complexes with a femtosecond time-resolved fluorescence spectroscopy. For linear carotenoids, the S$_2$ lifetimes showed the maximum value around n = 9-10. The conjugation of a keto-carbonyl group shortened the S$_2$lifetime and prolonged the S$_1$lifetime. The excitation relaxation dynamics within carotenoids and the excitation energy transfer kinetics from carotenoids to chlorophylls are discussed as a function of molecular structure of carotenoids.

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A Study on Characteristics of a Volatage-Applied Electrostatic Reducer (전압인가식 제전기의 특성에 관한 연구)

  • 이동훈;정용철
    • Journal of the Korean Society of Safety
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    • v.10 no.2
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    • pp.77-83
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    • 1995
  • An electrostatic reducer of a multi-pole high DC voltage applied type and a high frequency square wave voltage applied type have been studied to eliminate effectively and safely electrostatic charge on a dummy charged material. As a fundamental experiments, measurement were made on the decay time as a function of distance between electrostatic reducer and charged body, skewed angle of electrostatic reducer installed and wind speed of generated ions(+ or -) by electrostatic reducer with high DC voltage and high frequency square wave voltage. Based oil the results above, a appropriate installation and method were produced as a trial for factory.

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OPTIMAL CONTROL PROBLEMS FOR PARABOLIC HEMIVARIATIONAL INEQUALITIES WITH BOUNDARY CONDITIONS

  • Jeong, Jin-Mun;Ju, Eun-Young;Kim, Hyun-Min
    • Journal of the Korean Mathematical Society
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    • v.52 no.3
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    • pp.567-586
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    • 2015
  • In this paper, we study optimal control problems for parabolic hemivariational inequalities of dynamic elasticity and investigate the continuity of the solution mapping from the given initial value and control data to trajectories. We show the existence of an optimal control which minimizes the quadratic cost function and establish the necessary conditions of optimality of an optimal control for various observation cases.

Stability of matching boundary conditions for diatomic chain and square lattice

  • Ji, Songsong;Tang, Shaoqiang
    • Coupled systems mechanics
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    • v.7 no.3
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    • pp.255-268
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    • 2018
  • Stability of MBC1, a specific matching boundary condition, is proved for atomic simulations of a diatomic chain. The boundary condition and the Newton equations that govern the atomic dynamics form a coupled system. Energy functions that decay along with time are constructed for both the boundary with the same type atoms and the one with different type atoms. For a nonlinear chain, MBC1 is also shown stable. Numerical verifications are presented. Moreover, MBC1 is proved to be stable for a two dimensional square lattice.