an air filter is a significant element of any mechanical ventilation system. however, the importance and performance evaluation of air filters have not been well publicized and related scientific reports are scarce. in this study, a transportable, off-line, air filter-testing unit (the unit) was designed and utilized to simulate the filter housing of a mechanical ventilation system. the unit wa...

This paper presents a low-complexity variable step-size control for acoustic echo cancellation filters. The proposed control method is based on two supplementary adaptive filters with low memory length. The first supplementary filter is used to control the double-talk situations while the second supplementary filter is employed to detect variations of the echo-path impulse response. The variabl...

In this paper, we describe a method for real-time tracking of objects with multiple laser range-finders covering a workspace in a parallel and distributed fashion. Tracking people is a popular problem in machine vision. Here we adapt the methods used in vision to planar laser scanners. We group range measurements into entities like blobs and objects. With the help of a Kalman Filter (KF), the t...

A high-end smartphone must filter the transmit and receive paths for 2G, 3G, and 4G wireless access methods in up to 15 bands, as well as Wi-Fi, Bluetooth and the receive path of GPS receivers. Signals in the receive paths must be isolated from one another. They also must reject other extraneous signals whose causes are too diverse to list. To do so, a multi-band smartphone will require eight o...

It is shown that allpole filters of secondand third-order can be significantly desensitized to component tolerances by so-called impedance tapering, i.e., successively impedance-scaling upwards the Lsections of a resistance–capacitance ladder network in the forward and feedback path of a single-amplifier active filter. In order to obtain a realizable filter, certain constraints on the design eq...

This paper presents a hybrid active noise canceling (HANC) algorithm to overcome the acoustic feedback present in most ANC system, together with an efficient secondary path estimation scheme. The HANC system provides a solution of two fundamental problems present in these kind of ANC systems: The first consists in a reduction of the acoustic feedback from the cancellation loudspeaker to the inp...

BACKGROUND It is widespread practice during citrate anticoagulated renal replacement therapy to monitor circuit ionised calcium (iCa2+) to evaluate the effectiveness of anticoagulation. Whether the optimal site to sample the blood path is before or after the haemofilter is a common question. METHODS Using a prospectively collected observational dataset from intensive care patients receiving p...

This paper presents a vision-based collision avoidance technique for small and Miniature Air Vehicles (MAVs) using local-level frame mapping and path planning. Using computer vision algorithms, a depth map that represents the range and bearing to obstacles is obtained. Based on the depth map, we estimate the range, azimuth to, and height of obstacles using an extended Kalman Filter (EKF) that t...

In this paper we consider estimation of dynamical systems over wireless fading communication channels using a Kalman filter. We show the impact of the stochastic communication noise on the estimation process. We furthermore show how noisy packets should be handled in the receiver. More specifically, we illustrate the impact of the availability of a cross-layer information path on the optimum re...

Quagga is a software routing suite which provides implementations of various routing protocols for UNIX based platforms. It supports implementations of RIP, OSPF and BGP version 4. Path-exploration damping (or simply path-damping) is one possible approach to filter out the path hunting phenomenon in BGP, in which a single prefix withdrawal event at the original announcement’s origin may generat...