By obtaining a feasible filter function,reconstructed images can be got with linear interpolation and liftered backprojection techniques.Considering the gray and spstial correlation neighbour informations of each pixe...By obtaining a feasible filter function,reconstructed images can be got with linear interpolation and liftered backprojection techniques.Considering the gray and spstial correlation neighbour informations of each pixel,a new supervised classification method is put forward for the reconstructed images,and an experiment with noise image is done,the result shows that the method is feasible and accurate compared with ideal phantoms.展开更多
The study of paper damage under bombardments of protons and X--rays is reported. An on--demand beam pulsing system is useful for the PIXE analysis of delicate objectS. IXX (or PIXE--induced XRF) is more suitable than ...The study of paper damage under bombardments of protons and X--rays is reported. An on--demand beam pulsing system is useful for the PIXE analysis of delicate objectS. IXX (or PIXE--induced XRF) is more suitable than PIXE in terms of damage to the sample. Some new PIXE and IXX applications of archaeological paper--like samples in recent years are given.展开更多
The monitor is composed of a pair of electrodes,a single stage of microchannel plate,a phosphor screen,a CCD camera and a PC computer,To obtain a good uniform collecting field,forming electrodes system is used instead...The monitor is composed of a pair of electrodes,a single stage of microchannel plate,a phosphor screen,a CCD camera and a PC computer,To obtain a good uniform collecting field,forming electrodes system is used instead of that with a resistive divider,The readout system is performed by the phosphor screen and the CCD camera because the spatial resolution is not limited by the mechanical structure like the anode strip type and such video display system is very useful for beam studies and operation of the 40MeV linac,Besides,the design and test results are described in detail.展开更多
文摘By obtaining a feasible filter function,reconstructed images can be got with linear interpolation and liftered backprojection techniques.Considering the gray and spstial correlation neighbour informations of each pixel,a new supervised classification method is put forward for the reconstructed images,and an experiment with noise image is done,the result shows that the method is feasible and accurate compared with ideal phantoms.
文摘The study of paper damage under bombardments of protons and X--rays is reported. An on--demand beam pulsing system is useful for the PIXE analysis of delicate objectS. IXX (or PIXE--induced XRF) is more suitable than PIXE in terms of damage to the sample. Some new PIXE and IXX applications of archaeological paper--like samples in recent years are given.
文摘The monitor is composed of a pair of electrodes,a single stage of microchannel plate,a phosphor screen,a CCD camera and a PC computer,To obtain a good uniform collecting field,forming electrodes system is used instead of that with a resistive divider,The readout system is performed by the phosphor screen and the CCD camera because the spatial resolution is not limited by the mechanical structure like the anode strip type and such video display system is very useful for beam studies and operation of the 40MeV linac,Besides,the design and test results are described in detail.
