The primary aim of the study was to analyse the non-steady state of filtration for selected electrostatic filter materials designed for use in respiratory protective devices. The obtained results showed that the filtration process in electrostatic filters was dependent in the main on the following factors: type of the filter material, electrostatic field strength of the material, and the charge...

BACKGROUND Different filtering devices are used during mechanical ventilation to avoid dysfunction of flow and pressure transducers or for airborne microorganisms containment. Water condensates, resulting from the use of humidifiers, but also residual nebulization particles may have a major influence on expiratory limb resistance. OBJECTIVES To evaluate the influence of nebulization and activ...

Photonic crystal ring resonators (PCRRs) are traditional structures fordesigning optical channel drop filters. In this paper, Photonic crystal channel drop filter(CDFs) with a new configuration of ring resonator is presented. The structure is made ofa square lattice of silicon rods with the refractive index nsi=3. 4 which are perforated inair with refractive index nair=1. Calculations of band s...

We investigate the impact of the intrinsicof the resonant poles on the performance of multiring-based optical filters and dispersion-compensating devices. We highlight the role of quality factor by defining figures-of-merit for some specific filter configurations.

In this paper we present a wearable positioning system that requires 2.5 mA to operate. The system consists of an infrastructure of ultrasonic transmitting devices, and a receiver device on the wearable. The receiver comprises an ultrasonic pick-up, an op-amp, and a PIC. The PIC implements a particle filter for estimating X and Y positions. The transmitter layout has been chosen to simplify the...

A 24-bit, 96 kHz stereo A/D converter (ADC) for DVD-audio has been developed. The single-chip integrates stereo delta-sigma modulators (∆ΣM’s), a voltage reference, and a decimation filter. A fourth-order cascaded ∆ΣM using a local feedback technique was employed to avoid overload without sacrificing noise performance. Low power switched-capacitor techniques were used for implementation. A two-...

This paper presents new Wide Bandpass Filter (WBPF) and Narrow Bandstop Filter (NBSF) incorporating two microstrip resonators, each resonator is based on 2nd iteration of Hilbert fractal geometry. The type of filter as pass or reject band has been adjusted by coupling gap parameter (d) between Hilbert resonators using a substrate with a dielectric constant of 10.8 and a thickness of 1.27 mm. Nu...

The design of microwave filters and multiplexers usually starts with the synthesis of an equivalent circuit for determining the optimal architecture of the device. One can observe that the requirements for filtering devices in the last-generation of communication systems have broadened the area of traditional filter synthesis. In the recent years, many studies have concerned the synthesis of ad...

With the development of critical loads, power quality problem has become particularly important and poor power quality will be cause many adverse effects and the cost of many deaths will follow. To improve power quality and protection of sensitive loads against grid disturbances have been used new equipment based on power electronics similar FACTs devices, they are Custom Power. One of the most...

In this paper, we analyze a distributed amplifier based on input/output attenuation compensation. The analysis is carried out for a HEMT transistor; and a constant-k section filter is used to calculate the amplifier’s characteristics such as attenuation factor, phase constant and gain. The proposed design approach enables us to examine the tradeoff among the variables, which include the type an...