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Numerical analysis on car-following traffic flow models with delay time

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第2期7卷 204-209页

作者：李莉施鹏飞 Institute of Image Processing and Pattern Recognition Shanghai Jiao Tong University Shanghai 200030 China

Effects of the speed relaxation time on the optimal velocity car-following model (OVM) with delay time due to driver reaction time proposed by Bando et al.(1995) were studied by numerical methods. Results showed that the OVM including the delay is not physically sensitive to the speed relaxation times. A modified car-following model is proposed to overcome the deficiency. Analyses of the linear stability of the modified model were conducted. It is shown that coexisting flows appear if the initial homogeneous headway of the traffic flow is between critical values. In addition, phase transitions occur on varying the initially homogeneous headway.

关键词： Car-following models delay time Relaxation time Phase transitions

Investigating the effects of gradual deployment of market penetration rates(MPR)of connected vehicles on delay time and fuel consumption

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Journal of Intelligent and Connected Vehicles 2022年第3期5卷 188-198页

作者： Alireza Ansariyar Milad Tahmasebi Department of Transportation and Urban Infrastructure Morgan State UniversityBaltimoreMarylandUSA Department of Civil and Environmental Engineering Northeastern University College of EngineeringBostonMassachusettsUSA

Purpose–This research paper aims to investigate the effects of gradual deployment of market penetration rates(MPR)of connected vehicles(MPR of CVs)on delay time and fuel ***/methodology/approach–A real-world origin-destination demand matrix survey was conducted in Boston,MA to identify the number of peak hour passing vehicles in the case ***–The results showed that as the number of CVs(MPR)in the network increases,the total delay time decreases by an average of 14%and the fuel consumption decreases by an average of 56%,respectively,from scenarios 3 to 15 compared to scenario *** limitations/implications–The first limitation of this study was considering a small *** considered network shows a small part of the case ***/value–This study can be a milestone for future research regarding gradual deployment of CVs’effects on transport *** policy(s)may define based on the results of this network for Brockton transport network.

关键词： Connected vehicles(CVs) V2X module AIMSUN microsimulation Market penetration rate of CV delay time Fuel consumption

Determination of delay time in individual transfer function for central aortic pressure reconstruction

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Science China(Life Sciences) 2014年第10期57卷 1034-1038页

作者： YU DanYang XIANG HaiYan LI DeYu WANG YuQi YU MengSun School of Biological Science and Medical Engineering Beihang University Department of Medical Engineering the 201st Hospital of the Chinese Peoples' s Liberation Army Department of Aviation Medical Engineering Institute of Aviation Medicine

In previous research, time-delay （△t） was a more important parameter than the reflection coefficient in the individual transfer function of central aortic pressure reconstruction. The At can be obtained by electrocardiography （ECG） or phonocardiography （PCG）. Because the pre-ejection period remains an uncertain factor, the present study used ECG and PCG to define the delay time and analyzed the accuracy of the reconstruction results. The △tpre is the actual delay time derived from the aorta to the carotid pressure wave, △tpco is the time delay between the aortic valve component of the second heart sound and the dicrotic incisura of the carotid pressure wave, and AtEcc represents the delay from the interval of the ECG R-peak to the foot of the carotid pressure wave. Compared with the measured aortic pressure, the reconstruction result obtained by △t=△tpcslightly differed from the best result estimated by △t=△tpre. However, the differences between the result obtained by △t=△tEco and the best result were significant in terms of the diastolic blood pressure, and pulse pressure, and especially in terms of the augmentation index and root-mean-square-error. Thus, the At should be determined by PCG for central aortic pressure reconstruction in practice.

关键词： central aortic pressure delay time PCG ECG

Transient Properties of a Bistable System with delay time Driven by Non-Gaussian and Gaussian Noises:Mean First-Passage time

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Communications in Theoretical Physics 2008年第9期50卷 669-673页

作者： LI Dong-Xi XU Wei GUO Yong-Feng LI Gao-Jie Department of Applied Mathematics Northwestern Polytechnical University Xi＇an 710072 China

The mean first-passage time of a bistable system with time-delayed feedback driven by multiplicative non-Gaussian noise and additive Gaussian white noise is investigated. Firstly, the non-Markov process is reduced to the Markov process through a path-integral approach; Secondly, the approximate Fokker-Planck equation is obtained by applying the unified coloured noise approximation, the small time delay approximation and the Novikov Theorem. The functional analysis and simplification are employed to obtain the approximate expressions of MFPT. The effects of non-Gaussian parameter （measures deviation from Gaussian character） r, the delay time τ, the noise correlation time to, the intensities D and a of noise on the MFPT are discussed. It is found that the escape time could be reduced by increasing the delay time τ, the noise correlation time τ0, or by reducing the intensities D and α. As far as we know, this is the first time to consider the effect of delay time on the mean first-passage time in the stochastic dynamical system.

关键词： mean first-passage time delay time non-Gaussian noise Gaussian noise bistable system

Inspection-Based Policy Considering Human Errors for Three-Stage delay time Degradation Systems

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Journal of Shanghai Jiaotong university(Science) 2018年第5期23卷 702-706页

作者： ZHAO Fei LIU Xuejuan PENG Rui School of Business Administration Northeastern UniversityShenyang 110819China School of Management Northeastern University at QinhuangdaoQinhuangdao 066004HebeiChina Donlinks School of Economics and Management University of Science and Technology BeijingBeijing 100083China

A periodic inspection policy for a single component system based on a three-stage failure process is proposed, and two different kinds of failures covering "hard" and "human" are considered in the proposed *** system is periodically inspected and inspections are perfect so that they can identify the intended *** the severe defect is detected by an inspection, an immediate repair is needed. However, once the system is identified to be in the minor defective state, there are two options. The first is to do nothing till the arrival of identifying the severe defect or hard failure, and the second is to repair immediately. Repair for any defect can renew the system with a limited probability such that the system may fail after repair due to human errors, which is common in many industrial applications. Two models are constructed by minimizing the expected cost per unit time and compared. We provide a numerical example to demonstrate the proposed model.

关键词： delay time preventive maintenance inspection human errors renewal theory

Selection of Embedding Dimension and delay time in Phase Space Reconstruction

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Frontiers of Electrical and Electronic Engineering in China 2006年第1期1卷 111-114页

作者： MA Hong-guang HAN Chong-zhao Research Institute of High Technology Xi’an 710025China

A new algorithm is proposed for computing the embedding dimension and delay time in phase space *** makes use of the zero of the nonbias multiple autocorrelation function of the chaotic time series to determine the time delay,which efficiently depresses the computing error caused by tracing arbitrarily the slop variation of average displacement(AD)in AD ***,by means of the iterative algorithm of multiple autocorrelation andΓtest,the near-optimum parameters of embedding dimension and delay time are *** algorithm is provided with a sound theoretic basis,and its computing complexity is relatively lower and not strongly dependent on the data *** simulated experimental results indicate that the relative error of the correlation dimension of standard chaotic time series is decreased from 4.4%when using conventional algorithm to 1.06%when using this *** accuracy of invariants in phase space reconstruction is greatly improved.

关键词： phase space reconstruction embedding dimension delay time multiple autocorrelation Γtest

Effect of delay time between pre-pulse and main pulse on single-pass and double-pass amplification of 46.9 nm laser

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Chinese Optics Letters 2023年第5期21卷 104-109页

作者：赵东迪赵永蓬崔怀愈安博李镭白云松 National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of TechnologyHarbin 150080China

In this paper,the influence of the delay time between the pre-pulse and the main pulse on the double-pass amplified 46.9 nm laser was studied for the first time,to the best of our knowledge,by using a high-precision polished SiC slice as a rear *** temporal and spatial characteristics of the output laser were measured separately to investigate the effect of the delay time on the laser *** energy of the double-pass amplified laser was between 510μJ and 890μ*** addition,a theoretical model of double-pass amplification was established to analyze the effect of the delay time on the double-pass amplified 46.9 nm laser.

关键词： double-pass amplification delay time 46.9 nm laser capillary discharge

Behavior of Liquid-Liquid Dispersions in a Stirred Vessel——Part 2: Phase Inversion delay time

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Tsinghua Science and Technology 2001年第2期6卷 189-192页

作者：刘金晨陈健 Department of Chemical Fngineering Tsinghua University Beijing 100084 China Department of Chemical Engineering Tokyo Institute of Technology Tokyo 152-8552 Japan

A delay time was observed for both W/O inversion to O/W and the opposite inversion process. The delay time decreased with increasing stirring speed. For O/W inversion to W/O, the delay time was very sensitive to the oil volume fraction and the initial stirring speed. Increased oil volume fraction and increased initial stirring speed both reduced the delay time. Inversion from W/O to O/W was a gradual process. But inversion from O/W to W/O had two stages: the preparation stage and the phase inversion stage. The time needed in the first stage was the delay time.

关键词： liquid-liquid dispersions phase inversion delay time stirred vessel

The influence of time delay on forward masking when spatially separated sound image reproduced with headphone

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Chinese Journal of Acoustics 2008年第4期27卷 289-296页

作者： XIE Zhiwen JIN Jing School of Physics & technology South China University of Technology Guangzhou 510640

With the virtual reproduction of headphone, the influence of delay time between masker and masked signal on forward masking when sound images are virtually spatial separated in azimuth is studied. The result shows that the thresholds tend to decrease dramatically with the increase in delay time. Furthermore, in case of spatial separation, there are differences of masking thresholds with the maximum about 15 dB. However, when the masker level is 70 dB, the difference of the thresholds increases a little as the delay time increases from 20 ms to 40 ms, which can be explained by the time integration effect and basilar membrane response.

关键词： forward masking delay time time integration