PURPOSE To study the nonlinearity of myocardial signal intensity and gadolinium contrast concentration during first-pass perfusion MRI, and to compare quantitative perfusion estimates using nonlinear myocardial signal intensity correction. MATERIALS AND METHODS The nonlinearity of signal intensity and contrast concentration was simulated by magnetization modeling and evaluated in phantom meas...

To alleviate excessive smoothing of high signal-to-noise ratio (SNR) regions which are correspond to the structural features of MR images by using classical anisotropic diffusion (AD) filter. A novel AD filter called SNR controlled anisotropic diffusion is proposed. In this filter, an adaptive diffusivity function which is based on the correction factor of MR images was constructed. This adapti...

A power factor correction (PFC) converter with interleaved multi-channel topology is gaining increasing attention due to its ability in reducing input and output current ripples, but an Electromagnetic Interference (EMI) noise filter is still required for suppressing the large high-frequency switching noise that could potentially degrade the input power quality of the supplying grid and cause m...

Due to widespread use of Global Positioning System (GPS) in different applications, the issue of GPS signal interference cancelation is becoming an increasing concern. One of the most important intentional interferences is spoofing signals. An effective interference (delay spoof) reduction method based on adaptive filtering is developed in this paper. The principle of method is using adaptive f...

abstract comparison of food prices in different periods, indicates fluctuations and continually upward trend. any change in agricultural sector variables, as main food supplier, will affect food price. productivity shocks and production gap are examples of such variables. in this paper ,hodrick prescott and kalman filters are used as generators of productivity shocks and production gap series. ...

In signal processing and communication systems digital filters are widely used. The reliability of those systems is critical in some cases, and fault tolerant filter implementations are needed. Many techniques that exploit the filters' structure and properties to achieve fault tolerance have been proposed over the years. As technology scales, it enables more complex systems that incorporat...

A compensation scheme is proposed for plants subject to both saturation and backlash in series at the actuator. It is shown that the series connection of a backlash inverse, saturation and the backlash itself is equivalent to a saturation function at a different level to the original saturation; we call this the ‘saturation equivalence’. Therefore it is proposed to include such a backlash inver...

With progress in radar systems, a number of methods have been developed for signal processing and detection in radars. A number of modern radar signal processing methods use time-frequency transforms, especially the wavelet transform (WT) which is a well-known linear transform. The interference canceling is one of the most important applications of the wavelet transform. In Ad-hoc detection met...