• Title/Summary/Keyword: Decay time

Search Result 887, Processing Time 0.034 seconds

Time Series Prediction Using a Multi-layer Neural Network with Low Pass Filter Characteristics (저주파 필터 특성을 갖는 다층 구조 신경망을 이용한 시계열 데이터 예측)

  • Min-Ho Lee
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.21 no.1
    • /
    • pp.66-70
    • /
    • 1997
  • In this paper a new learning algorithm for curvature smoothing and improved generalization for multi-layer neural networks is proposed. To enhance the generalization ability a constraint term of hidden neuron activations is added to the conventional output error, which gives the curvature smoothing characteristics to multi-layer neural networks. When the total cost consisted of the output error and hidden error is minimized by gradient-descent methods, the additional descent term gives not only the Hebbian learning but also the synaptic weight decay. Therefore it incorporates error back-propagation, Hebbian, and weight decay, and additional computational requirements to the standard error back-propagation is negligible. From the computer simulation of the time series prediction with Santafe competition data it is shown that the proposed learning algorithm gives much better generalization performance.

  • PDF

Quantitative Measurement of Frustration for Multitasking Environment (다중작업 환경에서 좌절감의 정량적 측정방법)

  • Jeong, Sungoo;Myung, Rohae
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.43 no.3
    • /
    • pp.176-183
    • /
    • 2017
  • In recent years, studies about multitasking becomes more important. During multitasking, operators can feel frustration when they are interrupted during the task and frustration can affect operator's emotional state and performance. However there is no research on measuring the frustration quantitatively in multitasking environment. In this paper, we suggested quantitative measurement of frustration during multitasking. In order to measure the frustration, we made a mathematical representation with emotional decay model and the initial intensity of frustration based on cognitive closure theory. The amount of initial intensity could be represented as the ratio of actual remaining time to expected remaining time. By the experiment, we measured the frustration during the experiment and compared this values with values of frustration dimension of NASA-TLX. Finally we got the linear regression model with a good accuracy ($R^2=0.986$). This study contributes to measuring the emotion quantitatively by the relation of expected and actual remaining time in multitasking environment.

Photophysical Model of 10-Hydroxybenzo[h]quinoline: Internal Conversion and Excited State Intramolecular Proton Transfer

  • Lee, Junghwa;Joo, Taiha
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.3
    • /
    • pp.881-885
    • /
    • 2014
  • Photophysics of 10-hydroxybenzo[h]quinoline (HBQ) has been in controversy, in particular, on the nature of the electronic states before and after the excited state intramolecular proton transfer (ESIPT), even though the dynamics and mechanism of the ESIPT have been well established. We report highly time resolved fluorescence spectra over the full emission frequency regions of the enol and keto isomers and the anisotropy in time domain to determine the accurate rates of the population decay, spectral relaxation and anisotropy decay of the keto isomer. We have shown that the ~300 fs component observed frequently in ESIPT dynamics arises from the $S_2{\rightarrow}S_1$ internal conversion in the reaction product keto isomer and that the ESIPT occurs from the enol isomer in $S_1$ state to the keto isomer in $S_2$ state.

Fast response time PDP phosphors for 3D display application

  • Song, Jay-Hyok;Song, Yu-Mi;Kim, Ji-Hyun;Kim, Min-Ju;Kim, Ji-Hyun;Kwon, Seon-Young;Park, Do-Hyung;Kim, Yoon-Chang;Zang, Dong-Sik
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.1255-1258
    • /
    • 2008
  • New phosphors that enable the 3D application of PDP have been developed The decay times of $Y_3Al_5O_{12}:Ce^{3+}$, $(Y,Gd)Al_3(BO_3)_4:Tb^{3+}$ and $(Y,Gd)_2O_3:Eu^{3+}$ were extremely shorter than those of conventional PDP phosphors. The color coordinates and intensities of the phosphors were also suitable for PDP For the first time in PDP industry, 3D/2D switchable PDP has been commercially available by adopting the phosphors.

  • PDF

ASYMPTIOTIC BEHAVIOR FOR THE VISCOELASTIC KIRCHHOFF TYPE EQUATION WITH AN INTERNAL TIME-VARYING DELAY TERM

  • Kim, Daewook
    • East Asian mathematical journal
    • /
    • v.32 no.3
    • /
    • pp.399-412
    • /
    • 2016
  • In this paper, we study the viscoelastic Kirchhoff type equation with the following nonlinear source and time-varying delay $$u_{tt}-M(x,t,{\parallel}{\nabla}u(t){\parallel}^2){\Delta}u+{\int_{0}^{t}}h(t-{\tau})div[a(x){\nabla}u({\tau})]d{\tau}\\+{\parallel}u{\parallel}^{\gamma}u+{\mu}_1u_t(x,t)+{\mu}_2u_t(x,t-s(t))=0.$$ 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.

The Relaxation and Elimination Characteristics of Polarization-Photoinduced Dichrosim in Obliquely Deposited Amorphous Chalcogenide Thin Films (경사 증착된 비정질 칼코게나이드 박막에 평광-광유기된 이색성의 이완 및 소거 특성)

  • Park, Soo-Ho;Chun, Jin-Young;Lee, Hyun-Yong;Chung, Hong-Bay
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.11 no.10
    • /
    • pp.891-896
    • /
    • 1998
  • The relaxation and elimination characteristics of polarization-photoinduced dichroism have been investigated in amorphous chalcogenide thin films deposited having normal(0。) and obique (80。) vapor incident angles. The dark relaxation kinetics of dichroism from a saturation point(D\ulcorner\ulcorner) to a certain relaxation point(D\ulcorner\ulcorner) grew to be longer on subsequent cycles of switching on and off of the inducing light, and these decays are changed from simple exponential decay to stretched exponential decay. The dichroism induced by a long time(~3.3 hrs) exposure exhibited the characteristics of longer time maintenance and smaller decreasing rate, in contrast with that by a short time (~min) exposure. In addition, the dichroism was eliminated by the exposure of non-polarized He-Ne laser.

  • PDF

Carbonyl Emissions during Food Decay from Kimchi, Fish, and Salted Fish

  • Kabir, Ehsanul;Kim, Ki-Hyun
    • Asian Journal of Atmospheric Environment
    • /
    • v.2 no.2
    • /
    • pp.109-115
    • /
    • 2008
  • In this study, the emissions of carbonyl compounds as offensive odorants were measured using three food types (Kimchi, fresh fish, and salted fish) as a function of time. Odor samples for each food type, collected at 0, 1, 3, 7, and 14 days, were analyzed by high performance liquid chromatography (HPLC). Only three kinds of carbonyl compounds were quantified above their respective detection limits: formaldehyde, acetaldehyde, and acetone. The emission patterns of these compounds were distinguishable from each other. Formaldehyde tends to peak at the beginning and decrease through time with unique patterns. Conversely, acetaldehyde and acetone seem to increase gradually through time. The results showed that relative patterns of carbonyl emissions were more distinguishable by compound type rather than food type.

Measurements of Optical Constants of Biomedical Media Based on Time-Resolved Reflectance (시간 분해 반사율 측정에 의한 다중산란 매질의 광학 계수 측정)

  • Jeon, K.J.;Park, S.H.;Kim, U.;Yoon, K.W.;Kim, W.K.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1996 no.05
    • /
    • pp.235-239
    • /
    • 1996
  • In recent years, the optical properties of multiple-scattering media like tissue have been studied for their potential applications in medicine. In this work the optical properties of multiple scattering media were investigated using the time-resolved reflectance measurement. The reflected light was measured by time-correlated single photon counting system. The transport scattering and absorption coefficient are related to the initial rapid decay and the subsequent decay in reflected light, respectively. Also the optical properties of the samples were measured by conventional method, ie., using continuous wave light. When the distance between the light source and the detector is over 8mm, the optical coefficient can be measured accurately using the suggested method.

  • PDF

Analysis of Surface Degradation on Accelerated UV-treated Polymeric Housing Materials for Outdoor Insulator (자외선 가속열화에 따른 옥외용 폴리머 절연재료의 표면열화 분석)

  • Yeon, Bok-Hui;Lee, Sang-Yong;Heo, Chang-Su;Sim, Dae-Seop;Jo, Han-Gu
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.50 no.10
    • /
    • pp.479-488
    • /
    • 2001
  • The effects of accelerated Ultraviolet (UV) radiation on High temperature vulcanized (HTV), Room temperature vulcanized (RTV) silicone rubber and two types of ethylene propylene diene terpolymer (EPDM) used for composite insulator were inverstigated by hydrophobicity class (HC), surface voltage decay after corona charging, SEM-EDS, FTIR and XPS. The contact angle in two kinds of silicone rubber was scarcely change, but EPDM occurred to the loss of hydrophobicity followed by surface cracking and chalking. The surface voltage decay on UV-treated silicone rubber and EPDM showed a different decay trend with UV treatment. EDS and XPS analysis indicated that the oxygen content increased with UV treatment time in all samples. For silicone rubber, the oxidized groups of inorganic silica-like structure increased with UV treatment time. The oxidized carbon of C=0, O=C-O in EPDM increased. These oxidized surface for each material had different electrostatic characteristics, so deposited charges were expected to have different impacts on their surface hydrophobicity. The degradation mechanism based on our results was discussed.

  • PDF

Fabrication of the Superconducting Flux Flow Transistor Using the ICP Etching Method (ICP 장치를 이용한 초전도 자속 흐름 트랜지스터의 링크 제작)

  • Gang, Hyeong-Gon;Im, Yeon-Ho;Im, Seong-Hun;Choe, Hyo-Sang;Han, Yun-Bong;Han, Byeong-Seong
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.50 no.10
    • /
    • pp.494-499
    • /
    • 2001
  • The effects of accelerated Ultraviolet (UV) radiation on High temperature vulcanized (HTV), Room temperature vulcanized (RTV) silicone rubber and two types of ethylene propylene diene terpolymer (EPDM) used for composite insulator were investigated by hydrophobicity class (HC), surface voltage decay after corona charging, SEM-ES, FTIR and XPS. The contact angle in two kinds of silicone rubber was scarcely change, but EPDM occurred to the loss of hydrophobicity followed by surface cracking and chalking. The surface voltage decay on UV-treated silicone rubber and EPDM showed a different decay trend with UV treatment. EDS and XPS analysis indicated that the oxygen content increased with UV treatment time in all samples. For silicone rubber, the oxidized groups of inorganic silica-like structure increased with UV treatment time. The oxidized carbon of C=O, O=C-O in EPDM increased. These oxidized surface for each material had different electrostatic characteristics, so deposited charges were expected to have different impacts on their surface hydrophobicity. The degradation mechanism based on our results was discussed.

  • PDF