Photonic computing has recently become an interesting paradigm for high-speed calculation of computing processes using light-matter interactions.Here,we propose and study an electromagnetic wave-based structure with t...Photonic computing has recently become an interesting paradigm for high-speed calculation of computing processes using light-matter interactions.Here,we propose and study an electromagnetic wave-based structure with the ability to calculate the solution of partial differential equations(PDEs)in the form of the Helmholtz wave equation,∇^(2)(x,y)T+k^(2)(x,y)=0,with k as the wavenumber.To do this,we make use of a network of interconnected waveguides filled with dielectric inserts.In so doing,it is shown how the proposed network can mimic the response of a network of T-circuit elements formed by two series and a parallel impedances,i.e.,the waveguide network effectively behaves as a metatronic network.An in-depth theoretical analysis of the proposed metatronic structure is presented,showing how the governing equation for the currents and impedances of the metatronic network resembles that of the finite difference representation of the Helmholtz wave equation.Different studies are then discussed including the solution of PDEs for Dirichlet and open boundary value problems,demonstrating how the proposed metatronic-based structure has the ability to calculate their solutions.展开更多
诊断准确性试验(diagnostic test accuracy,DTA)的灵敏度与特异度之间存在固有的负相关性,为避免二者间负相关性对诊断试验结果的评价产生影响,很多学者提出了双变量模型,因其保留了原始数据的二维结构特性,双变量模型通过参数拟合可以...诊断准确性试验(diagnostic test accuracy,DTA)的灵敏度与特异度之间存在固有的负相关性,为避免二者间负相关性对诊断试验结果的评价产生影响,很多学者提出了双变量模型,因其保留了原始数据的二维结构特性,双变量模型通过参数拟合可以得到灵敏度和特异度的综合估计量值及二者之间负相关的值,从而对诊断试验的准确性进行综合性分析。当前最具代表的是由Reitsma等提出的线性混合双变量模型,Metatron程序包正是基于此模型所研发的用于DTA Meta分析的程序包,同时本文将对R软件中专用于DTA Meta分析的程序包做出比较,便于使用者选择。展开更多
基金support of the Leverhulme Trust under the Leverhulme Trust Research Project Grant scheme(Grant No.RPG-2020-316)V.P-P.and R.G.M would like to thank the support from the Engineering and Physical Sciences Research Council(EPSRC)under the EPSRC DTP PhD scheme(Grant No.EP/T517914/1).
文摘Photonic computing has recently become an interesting paradigm for high-speed calculation of computing processes using light-matter interactions.Here,we propose and study an electromagnetic wave-based structure with the ability to calculate the solution of partial differential equations(PDEs)in the form of the Helmholtz wave equation,∇^(2)(x,y)T+k^(2)(x,y)=0,with k as the wavenumber.To do this,we make use of a network of interconnected waveguides filled with dielectric inserts.In so doing,it is shown how the proposed network can mimic the response of a network of T-circuit elements formed by two series and a parallel impedances,i.e.,the waveguide network effectively behaves as a metatronic network.An in-depth theoretical analysis of the proposed metatronic structure is presented,showing how the governing equation for the currents and impedances of the metatronic network resembles that of the finite difference representation of the Helmholtz wave equation.Different studies are then discussed including the solution of PDEs for Dirichlet and open boundary value problems,demonstrating how the proposed metatronic-based structure has the ability to calculate their solutions.
文摘诊断准确性试验(diagnostic test accuracy,DTA)的灵敏度与特异度之间存在固有的负相关性,为避免二者间负相关性对诊断试验结果的评价产生影响,很多学者提出了双变量模型,因其保留了原始数据的二维结构特性,双变量模型通过参数拟合可以得到灵敏度和特异度的综合估计量值及二者之间负相关的值,从而对诊断试验的准确性进行综合性分析。当前最具代表的是由Reitsma等提出的线性混合双变量模型,Metatron程序包正是基于此模型所研发的用于DTA Meta分析的程序包,同时本文将对R软件中专用于DTA Meta分析的程序包做出比较,便于使用者选择。
