Finely tuning spectral characteristics of the epsilon-negative(ε'<0,EN) response is full of challenges when its regulatory mechanism in metacomposites is not yet clear.Herein,we have meticulously designed Cu/C...Finely tuning spectral characteristics of the epsilon-negative(ε'<0,EN) response is full of challenges when its regulatory mechanism in metacomposites is not yet clear.Herein,we have meticulously designed Cu/CaCu_(3)Ti_(4)O_(12)(Cu/CCTO) percolative metacomposites,successfully achieved both epsilon-negative and ε'-near-zero(ENZ)responses in the radio-frequency band.Before percolation,a large number of electric dipoles in the metacomposites achieved resonance characteristics near the ENZ point under the excitation of radio frequency electromagnetic fields,and as the Cu content increased,the ENZ frequency varied from 942,858,862 to 632 MHz.展开更多
Let X and Y be positive weakly negatively dependent （WND） random variables with finite expectations and continuous distribution functions F and G with heavy tails, respectively. The asymptotic behavior of the tail o...Let X and Y be positive weakly negatively dependent （WND） random variables with finite expectations and continuous distribution functions F and G with heavy tails, respectively. The asymptotic behavior of the tail of distribution of XY is studied and some closure properties under some suitable conditions on F（x） = 1-F（x） and G（x） = of XY when X and Y are WND random variables 1- G（x） are provided. Moreover, subexponentiality is derived.展开更多
基金supported by the National Natural Science Foundation of China(No.52461002)
文摘Finely tuning spectral characteristics of the epsilon-negative(ε'<0,EN) response is full of challenges when its regulatory mechanism in metacomposites is not yet clear.Herein,we have meticulously designed Cu/CaCu_(3)Ti_(4)O_(12)(Cu/CCTO) percolative metacomposites,successfully achieved both epsilon-negative and ε'-near-zero(ENZ)responses in the radio-frequency band.Before percolation,a large number of electric dipoles in the metacomposites achieved resonance characteristics near the ENZ point under the excitation of radio frequency electromagnetic fields,and as the Cu content increased,the ENZ frequency varied from 942,858,862 to 632 MHz.
基金Supported by Ferdowsi University of Mashhad(Grant No.MS88076AMI)
文摘Let X and Y be positive weakly negatively dependent （WND） random variables with finite expectations and continuous distribution functions F and G with heavy tails, respectively. The asymptotic behavior of the tail of distribution of XY is studied and some closure properties under some suitable conditions on F（x） = 1-F（x） and G（x） = of XY when X and Y are WND random variables 1- G（x） are provided. Moreover, subexponentiality is derived.
