An SPECT system dedicated to small animal imaging shall be of a millimeter spatial resolution or even better.This study was aimed at achieving 0.5-mm spatial resolution for a small animal SPECT system at low cost.It w...An SPECT system dedicated to small animal imaging shall be of a millimeter spatial resolution or even better.This study was aimed at achieving 0.5-mm spatial resolution for a small animal SPECT system at low cost.It was developed from a single-head clinical SPECT scanner,with a seven-pinhole collimator and a four-degree-offreedom motion control stage.Several key techniques were developed,including high-resolution image reconstruction algorithm,high accuracy geometrical calibration method,and optimized system matrix derivation scheme.The system matrix was derived from Monte-Carlo simulation and de-noised by fitting each point spread function to a two dimensional Gaussian function.Experiments of point source and ultra micro hot rod phantom were conducted.With a spatial resolution of 0.5-0.6 mm,this system provides a practical way for low-cost high-resolution animal imaging on a clinic SPECT system.展开更多
假定Lf(x)=−1/ω(x)∑i,j∂i(aij(⋅)∂jf)(x)+V(x)f(x)为退化Schrödinger算子,其中ω是来自Muckenhoupt class A_(2)的权.又设V是非负位势,属于与ω(x)dx有关的反Hölder不等式.基于分数阶热半群{e^(−tLα)}_(t>0)的正则性估...假定Lf(x)=−1/ω(x)∑i,j∂i(aij(⋅)∂jf)(x)+V(x)f(x)为退化Schrödinger算子,其中ω是来自Muckenhoupt class A_(2)的权.又设V是非负位势,属于与ω(x)dx有关的反Hölder不等式.基于分数阶热半群{e^(−tLα)}_(t>0)的正则性估计,我们通过两个面积函数S_(α)^(L)和g_(α)^(L)来刻画与L有关的Hardy空间.展开更多
基金Supported by Specialized Research Fund for the Doctoral Program of Higher Education(SRFDP200800031071)National Natural Science Foundation of China (No.10975086)the National High Technology Research and Development Program of China(No.2006AA020802)
文摘An SPECT system dedicated to small animal imaging shall be of a millimeter spatial resolution or even better.This study was aimed at achieving 0.5-mm spatial resolution for a small animal SPECT system at low cost.It was developed from a single-head clinical SPECT scanner,with a seven-pinhole collimator and a four-degree-offreedom motion control stage.Several key techniques were developed,including high-resolution image reconstruction algorithm,high accuracy geometrical calibration method,and optimized system matrix derivation scheme.The system matrix was derived from Monte-Carlo simulation and de-noised by fitting each point spread function to a two dimensional Gaussian function.Experiments of point source and ultra micro hot rod phantom were conducted.With a spatial resolution of 0.5-0.6 mm,this system provides a practical way for low-cost high-resolution animal imaging on a clinic SPECT system.
基金Supported by Natural Science Foundation of Shandong Province(No.ZR2020MA004)NSFC(No.11871293)。
文摘假定Lf(x)=−1/ω(x)∑i,j∂i(aij(⋅)∂jf)(x)+V(x)f(x)为退化Schrödinger算子,其中ω是来自Muckenhoupt class A_(2)的权.又设V是非负位势,属于与ω(x)dx有关的反Hölder不等式.基于分数阶热半群{e^(−tLα)}_(t>0)的正则性估计,我们通过两个面积函数S_(α)^(L)和g_(α)^(L)来刻画与L有关的Hardy空间.
