TRIZ APPLICATION IN DEVICE & MANUFACTURING ELECTROSTATIC DISCHARGE CONTROL
A credit card pager having a casing surrounding a substrate and electronic circuitry mounted on the substrate. An information connection including at least one molded waveguide having a core with a photonic device mounted at one end and a second end of the core being positioned on the substrate to be accessible exterior of the casing so as to communicate optical information signals therethrough.
Building in reliability during ESD design layout
Building in reliability during ESD design layout is key to the success of product design and development. Due to the limitations of automated layout checkers for ESD, knowledge of fundamental device physics, ESD and stress environments are essential.
Monte Carlo Study of the Effect of Backscatter Materail Thickness on 99 mTc Source Response in Single Photon Emission Computed Tomography
Introduction SPECT projections are contaminated by scatter radiation, resulting in reduced image contrast and quantitative errors. Backscatter constitutes a major part of the scatter contamination in lower energy windows. The current study is an evaluation of the effect of backscatter material on FWHM and image quality investigated by Monte Carlo simulation. Materials and Methods SIMIND program was used for simulation of a Siemen’s dual-head variable angle scintillation gamma camera. Planar and SPECT scanning of a 99m Tc source and a Jaszczak phantom for varying thicknesses of Perspex slabs, as a backscatter media, were analyzed using the photopeak and scatter windows. Simulated planar images and reconstructed tomographic images were evaluated qualitatively, by two nuclear medicine specialists, and quantitatively, by Structural Similarity (SSIM) Index. Results In the 99m Tc photopeak window, no significant change in total counts due to backscatter material was measured. In the scatter windows, scattering was overestimated compared with a simulated backscatter free SPECT system. For instance, at a thickness of 10 cm, total counts of a 99m Tc source detected in the 72 keV windows eventually doubled with increasing backscatter material, compared with the situation without backscatter material. The backscatter contribution plateaued when more than 7 cm of scatter material was placed but there were optimized results for a backscatter thickness of 4.5 cm. Better image quality for the thickness was confirmed by the results of eye interpretation and also by SSIM algorithm. Conclusion Backscatter should be taken into account, particularly in model-based scatter correction methods in SPECT for an accurate simulation system optimization.