Polyphase FilterBanks (PFBs) provide a computationally efficient approach to extracting channels of arbitrary bandwidth from a wideband signal. This technique, know as digital downconversion, would find use in software radio applications. Conversely, PFBs can also be used to perform digital upconversion, a process in which a wideband signal is constructed from several narrowband channels. In th...

introduction: photon attenuation in tissues is the primary physical degrading factor limiting both visual qualitative interpretation and quantitative analysis capabilities of reconstructed single photon emission computed tomography (spect) images. the aim of present study was to investigate the effect of attenuation correction on the detection of activation foci following statistical analysis w...

Gaussian frequency shift keying is the modulation scheme specified for Bluetooth. Signal adversities typical in Bluetooth networks include AWGN, multipath propagation, carrier frequency, and modulation index offsets. In our effort to realise a robust but efficient Bluetooth receiver, we adopt a high-performance matched-filter-based detector, which is near optimal in AWGN, but requires a prohibi...

Filter amplification corrections are presented for eight marine centric diatoms. These functions are required to correct the amplified optical path-length associated with the glass-fiber filter used in the measurement of phytoplankton absorption. Correction factors constructed from phytoplankton cultures in the laboratory are often applied to phytoplankton assemblages in the field. This study d...

  Introduction: There are several technical features that make PET an ideal device for the noninvasive evaluation of cardiac physiology. Organ motion due to respiration is a major challenge in diagnostic imaging, especially in cardiac PET imaging. These motions reduce image quality by spreading the radiotracer activity over an increased volume, distorting apparent les...

This paper treats the problem of correction of loudspeaker and room responses using a single source. The objective is to obtain a linear correction filter, which is robust with respect to listener movement within a predefined region-of-interest. The correction filter is based on estimated impulse responses, obtained at several positions, and a linear minimum mean squared error criteria. The imp...

An automated routine method was developed for the determination of trace metals using a flow injection system into a direct current plasma spectrometer. The characteristic emission in the 'Spectra- Metrics' three-electrode jet is channelled through an echelle grating to the detector of the instrument. The emission signal is continuously recorded, and, after digitalization, calculated and record...

The paper describes a residual analysis-synthesis system which exploits the human perception mechanism on temporal varying signals using Zwicker's three dimensional excitation-critical-bandrate time pattern as the framework. Temporal information is retrieved using a linear predictive analysis on the discrete cosine transformed signal and critical band intensity information is obtained by using ...

This paper presents an efficient method of electrocardiogram signal denoising based on a hybrid approach. Two techniques are brought together to create an efficient denoising process. The first is an Adaptive Dual Threshold Filter (ADTF) and the second is the Discrete Wavelet Transform (DWT). The presented approach is based on three steps of denoising, the DWT decomposition, the ADTF step and t...

The extensive use of Schott BG3 glass filters in auroral physics demands an accurate characterization of the filter performance when observing actual auroral structures. We present observations from two identical Andor DU-888 imagers operated side-by-side, one equipped with a BG3 glass filter and the other one unfiltered, observing the same auroral structures. The BG3 glass filter decreased the...