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The paper presents a digest of chosen technical work results shown by young researchers from different technical universities in this country during the SPIE-IEEE Wilga 2011 symposium on Photonics and Web Engineering. Topical tracks of the symposium embraced, among others, nanomaterials and nanotechnologies for photonics and telecom, sensory and nonlinear optical fibers, object oriented design of...
The paper presents a digest of the research results in the domain of accelerator science and technology in Europe, shown during the annual meeting of the EuCARD - European Coordination of Accelerator Research and Development. The conference concerns building of the research infrastructure, including in this advanced photonic and electronic systems for servicing large high energy physics experiments...
This paper discusses the cued speech recognition methods in videoconference. Cued speech is a specific gesture language that is used for communication between deaf people. We define the criteria for sentence intelligibility according to answers of testing subjects (deaf people). In our tests we use 30 sample videos coded by H.264 codec with various bit-rates and various speed of cued speech. Additionally,...
The paper deals with the area of the technical solution of the information and navigation system intended for persons with visual impairment. The first part is focused on the transfer of information concerned using the conductivity properties of the human body as a transmission channel. This principle is referred to as Personal Area Network (PAN). The principle used of data transmission through the...
NCTI ("Non-Cooperative Target Identification") in a monostatic radar configuration has been investigated extensively within the past years but classification in a bi-/ multistatic configuration does not seem to have obtained much attention to date. Some differences between monostatic and bistatic radar pose challenges to NCTI, which have to be met especially if monostatic and bistatic data...
In the present paper we focus on online monitoring system for predictive maintenance based on sensor automated inputs. Our subject was a device from Maritsa East 2 power plant - a mill fan. The main sensor information we have access to is based on the vibration of the nearest to the mill rotor bearing block. Our aim was to create a (nonlinear) model able to predict on time possible changes in vibrations...
Application of ground-based SAR and differential interferometry technique is often used for monitoring manmade objects aiming detection of their structural changes. Recently Ka-band Ground Based Noise Waveform SAR has been developed [1] which may be applied for the above monitoring. The paper is devoted to investigation of stability of Noise Waveform SAR. Monitoring of a simple construction has been...
The Long-Term Evolution (LTE) is the next generation of current mobile telecommunication networks. LTE has a new flat radio-network architecture and a significant increase in spectrum efficiency. In this paper, a computationally-efficient tool for dynamic system-level LTE simulations is proposed. A physical layer abstraction is performed to predict link-layer performance with a low computational cost...
Technique for separate estimation of fast and slow fluctuations in the heart rate signal is developed. The orthogonal dyadic wavelet transform is used to separate the slow heart rate changes in approximation part of decomposition and fast changes in detail parts. Experimental results using the recordings from persons practicing Chi meditation demonstrated the applicability of estimation heart rate...
A Passive Coherent Location (PCL) Radar system, consisting of spatially distributed transmitters and receivers is currently being integrated at the University of Cape Town (UCT). The paper investigates the feasibility of real-time processing of PCL system signals using Graphic Processing Units (GPUs), specifically a study of two distinct clutter cancellation algorithms: ECA (Extensive Cancellation...
Noise radar is a very promising technology offering advantages which cannot be achieved in classical radar systems. Unfortunately, it has also several disadvantages. One of the most significant is the masking effect, where strong objects raise the noise floor preventing detection of weak ones and significantly affecting dynamic range. In this article method of designing waveform with reduced noise...
The paper presents a simulation model of the radio frequency MIMO-OFDM system. The simulation model was made in Matlab Simulink environment. It contains the transmitter, the receiver and the telecommunication channel models. The telecommunication channel model consists of models used during development of technical documentation of IEEE 802.11n. Signals generated at the transmitter output are fully...
Network calculus is a mathematical theory dealing with queueing problems in packet-switched computer networks. It provides algorithms to determine resource requirements of traffic flows using arrival and service curves and describes delays and backlogs in network systems. Network calculus framework is based on a min-plus algebra which allows to transform complex network optimization problems into...
This paper describes the adaptation of a computational technique utilizing Extended Kohonen Maps (EKMs) and Rao-Blackwell-Kolmogorov (R-B) Filtering mechanisms for the administration of Sensor-Actuator networks (SANETs). Inspired by the BDI (Belief-Desire-Intention) Agent model from Rao and Georgeff, EKMs perform the quantitative analysis of an algorithmic artificial neural network process by using...
Received Signal Strength Indication (RSSI) plays a vital role in the range-free localization of sensor nodes in a wireless sensor network and a good amount of research has been made in this regard. One important factor is the battery voltage of the nodes (i.e., the MICAz sensors) which is not taken into account in the existing literature. As battery voltage level performs an indispensable role for...
In this paper we discuss state of the art in the field of shielding materials investigation. Two types of newly manufactured shielding materials (nonwoven and fabric) were measured using improved free-space transmission technique at 2-5 GHz depending on electromagnetic wave (EM) polarization and antenna to specimen distance. Results of shielding effectiveness (SE) evaluation based on measured complex...
The paper describes how a linear combination of bicubic B-splines can be effectively used in a two-dimensional interpolation. It is assumed that values of a function to be interpolated are evaluated at the uniformly located nodes of a corresponding rectangular grid. All formulae of importance have been derived step by step and are presented in a form convenient for computer implementations. To ensure...
The performance and efficiency of a Wireless Sensor Network (WSN) is typically subject to techniques used in data routing, clustering, and localization. Being primarily driven by resource constraints, a Socionomic model has been formulated to optimize resource usage and boost collaboration among sensor nodes. In this paper, we present several experimental results to ascertain the underlying philosophy...
The paper presents the overview of the theory of 2-D complex and quaternion analytic signals with the 1st-quadrant spectrum support. Both signals are expressed as complex/hypercomplex sums of partial and total 2-D Hilbert transforms. Moreover, starting with the definition of 2-D complex and quaternion Fourier transforms, the 2-D Hilbert transforms are derived in the form of sums of parts of different...
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