3,974 research outputs found

    Signal Amplification Assisted by Multiple Sideband Interference in 1D Waveguide QED Systems

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    This study theoretically investigates signal amplification resulting from multiple Rabi sideband coherence in a one-dimensional waveguide quantum electrodynamical system. Specifically, we explore the behavior of a transmon while strongly driven by a coherent microwave field through a semi-infinite waveguide. To understand the underlying mechanisms of amplification, we develop a theory that explicitly takes into account multiple dressed sidebands under a strong driving field, and analyze the reflection amplitude of the probe signal. Our findings show that amplification can be related to either population inversion or multiple sideband constructive interference in some cases without population inversion. We further examine the effect of qubit dephasing during the amplification process

    Effects of System Characteristics on Adopting Web-Based Advanced Traveller Information System: Evidence from Taiwan

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    This study proposes a behavioural intention model that integrates information quality, response time, and system accessibility into the original technology acceptance model (TAM) to investigate whether system characteristics affect the adoption of Web-based advanced traveller information systems (ATIS). This study empirically tests the proposed model using data collected from an online survey of Web-based advanced traveller information system users. Con­firmatory factor analysis (CFA) was performed to examine the reliability and validity of the measurement model, and structural equation modelling (SEM) was used to evaluate the structural model. The results indicate that three system characteristics had indirect effects on the intention to use through perceived usefulness, perceived ease of use, and attitude toward using. Information quality was the most im­portant system characteristic factor, followed by response time and system accessibility. This study presents implica­tions for practitioners and researchers, and suggests direc­tions for future research.</p

    Design of Direct and Indirect Wind Energy Harvest Systems

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    -Developing wind energy by using wind collector and electroactive materials are proposed and investigated in this article. Two systems will be considered to harvest energy: direct and indirect system. In direct system, wind induced drag force directly blow and vibrate the electroactive materials in the duct for generating electricity. Wind flowguided mechanism is designed to collect arbitrarily blowing wind in environment and guide the flow direction perpendicular to the cross section of the nozzle as much as possible so that more uniform velocity distribution profile is achieved. Nozzle accelerator is designed for the purpose of increasing wind velocity. Indirect system uses gear as additional mechanism to impact and vibrate the electroactive materials. Two types of indirect system integrating the wind collector with fan and roof turbine ventilator to impact and vibrate electroactive materials are proposed

    Population Growth and Competition Models with Decay and Competition Consistent Delay

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    We derive an alternative expression for a delayed logistic equation in which the rate of change in the population involves a growth rate that depends on the population density during an earlier time period. In our formulation, the delay in the growth term is consistent with the rate of instantaneous decline in the population given by the model. Our formulation is a modification of [Arino et al., J.~Theoret.~Biol.~241(1):109--119, 2006] by taking the intraspecific competition between the adults and juveniles into account. We provide a complete global analysis showing that no sustained oscillations are possible. A threshold giving the interface between extinction and survival is determined in terms of the parameters in the model. The theory of chain transitive sets and the comparison theorem for cooperative delay differential equations are used to determine the global dynamics of the model. We extend our delayed logistic equation to a system modeling the competition of two species. For the competition model, we provide results on local stability, bifurcation diagrams, and adaptive dynamics. Assuming that the species with shorter delay produces fewer offspring at a time than the species with longer delay, we show that there is a critical value, τ\tau^*, such that the evolutionary trend is for the delay to approach τ\tau^*.Comment: 22 pages, 6 figures, 1 tabl

    Travelling wave solutions for Kolmogorov-type delayed lattice reaction–diffusion systems

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    [[abstract]]This work investigates the existence and non-existence of travelling wave solutions for Kolmogorov-type delayed lattice reaction–diffusion systems. Employing the cross iterative technique coupled with the explicit construction of upper and lower solutions in the theory of quasimonotone dynamical systems, we can find two threshold speeds c∗ and c∗ with c∗≥c∗>0. If the wave speed is greater than c∗, then we establish the existence of travelling wave solutions connecting two different equilibria. On the other hand, if the wave speed is smaller than c∗, we further prove the non-existence result of travelling wave solutions. Finally, several ecological examples including one-species, two-species and three-species models with various functional responses and time delays are presented to illustrate the analytical results.[[notice]]補正完畢[[journaltype]]國外[[incitationindex]]SCI[[ispeerreviewed]]Y[[booktype]]紙本[[countrycodes]]GB
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