Spectral bandwidth is a relevant parameter of water wave evolution and is commonly used to represent the number of wave components involved in wave-wave interactions.However,whether these two parameters are equivalent...Spectral bandwidth is a relevant parameter of water wave evolution and is commonly used to represent the number of wave components involved in wave-wave interactions.However,whether these two parameters are equivalent is an open question.Following the high-order spectral method and taking the weakly modulated Stokes wave train as the initial condition,the relationship between the spectral bandwidth and the number of wave components is investigated in this work.The results showed that the number of wave components can vary with the same spectral bandwidth and that distinct wave profiles emerge from different numbers of wave components.With a new definition of significant wave components,the characteristics of this parameter in the long-time wave evolution are discussed,along with its relationship with common parameters,including the wave surface maximum and the wave height.The results reveal that the wave surface evolution trend of different numbers of significant wave components(Ns)is the same from a holistic perspective,while the difference between them also exists,mainly in locations where extreme waves occur.Furthermore,there is a negative correlation between r(aj/a_(0))and wave surface maximum(η_(max)/a_(0))and wave height(H_(max)and Hs).The evolution trends of the relative errors(RE)ofη_(max)/a_(0),H_(max),and Hs of different Ns show the periodic recurrence of modulation and demodulation in the early stage when the Benjamin-Feir instability is dominated.The difference is that in the later stage,the RE ofη_(max)/a_(0)and H_(max)is chaotic and irregular,while those of Hs gradually stabilize near an equilibrium value.Furthermore,we discuss the relationship between the mean relative error(MRE)and r.Forη_(max)/a_(0),MRE and r show a logarithmic relationship,while for H_(max)and Hs,a quadratic relationship exists between them.Therefore,the choice of Ns is also important for extreme waves and is particularly meaningful for wave generation experiments in the wave flume.展开更多
RGB三基色的LCD显示器件在高端的应用领域已经不能满足细节显示要求。研究发现可以增加基色的数量,如黄色,形成RYGB四基色,实验证明显示的色域有明显的改善。文中首先研究LCD的电光特性,而后重点研究频谱带宽对LCD电光特性的影响。在1 k...RGB三基色的LCD显示器件在高端的应用领域已经不能满足细节显示要求。研究发现可以增加基色的数量,如黄色,形成RYGB四基色,实验证明显示的色域有明显的改善。文中首先研究LCD的电光特性,而后重点研究频谱带宽对LCD电光特性的影响。在1 k Hz固定频率驱动下,通过改变电压来改变LCD的透过率,随着驱动电压的变化,LCD的透过率有较大变化。选取四种基色对应的波长,研究它们的电光特性曲线,得出LCD四基色的电光特性曲线随电压变化的趋势一致;研究不同带宽下四基色波长的透过率,得出带宽对红、黄、绿三种基色的透过率影响不大,而带宽对蓝基色的透过率影响较大。展开更多
基金the National Key Research and Development Program of China(Grant No.2022YFE0104500)the National Natural Science Foundation of China(Grant No.52271271)the Major Science and Technology Project of the Ministry of Water Resources of the People’s Republic of China(Grant No.SKS-2022025).
文摘Spectral bandwidth is a relevant parameter of water wave evolution and is commonly used to represent the number of wave components involved in wave-wave interactions.However,whether these two parameters are equivalent is an open question.Following the high-order spectral method and taking the weakly modulated Stokes wave train as the initial condition,the relationship between the spectral bandwidth and the number of wave components is investigated in this work.The results showed that the number of wave components can vary with the same spectral bandwidth and that distinct wave profiles emerge from different numbers of wave components.With a new definition of significant wave components,the characteristics of this parameter in the long-time wave evolution are discussed,along with its relationship with common parameters,including the wave surface maximum and the wave height.The results reveal that the wave surface evolution trend of different numbers of significant wave components(Ns)is the same from a holistic perspective,while the difference between them also exists,mainly in locations where extreme waves occur.Furthermore,there is a negative correlation between r(aj/a_(0))and wave surface maximum(η_(max)/a_(0))and wave height(H_(max)and Hs).The evolution trends of the relative errors(RE)ofη_(max)/a_(0),H_(max),and Hs of different Ns show the periodic recurrence of modulation and demodulation in the early stage when the Benjamin-Feir instability is dominated.The difference is that in the later stage,the RE ofη_(max)/a_(0)and H_(max)is chaotic and irregular,while those of Hs gradually stabilize near an equilibrium value.Furthermore,we discuss the relationship between the mean relative error(MRE)and r.Forη_(max)/a_(0),MRE and r show a logarithmic relationship,while for H_(max)and Hs,a quadratic relationship exists between them.Therefore,the choice of Ns is also important for extreme waves and is particularly meaningful for wave generation experiments in the wave flume.
文摘RGB三基色的LCD显示器件在高端的应用领域已经不能满足细节显示要求。研究发现可以增加基色的数量,如黄色,形成RYGB四基色,实验证明显示的色域有明显的改善。文中首先研究LCD的电光特性,而后重点研究频谱带宽对LCD电光特性的影响。在1 k Hz固定频率驱动下,通过改变电压来改变LCD的透过率,随着驱动电压的变化,LCD的透过率有较大变化。选取四种基色对应的波长,研究它们的电光特性曲线,得出LCD四基色的电光特性曲线随电压变化的趋势一致;研究不同带宽下四基色波长的透过率,得出带宽对红、黄、绿三种基色的透过率影响不大,而带宽对蓝基色的透过率影响较大。
