This paper investigates error performance of the narrow-band (NB) power-line carrier (PLC) communication system from a distribution system operator (DSO) perspective, with measurement data collected in the rural 400 V distribution grid. The performance evaluation is founded on the three aspects: attenuation of the NB PLC channel, frequency of the signal to noise ratio (SNR) class occurrence detected in a receiver and bit error rate (BER) analysis. The true BER is estimated from the limited amount of collected data using error model based on Neyman type A contagious distribution, appropriate for communication channels with impulsive noise. Results confirmed that PRIME-based NB PLC deployments for smart metering applications are adequate in rural distribution grids, even in cases with high attenuation and articulated frequency variations in a PLC channel. DOI: http://dx.doi.org/10.5755/j01.eie.24.1.20149

Recent advances in the development of wearable sensors and smartphones open up opportunities for executing computing operations on the devices instead of using them for streaming raw d ...

Overvoltage protection systems are used to protect sensitive electrical and electronic equipment from voltage surges and lightning strikes. These systems are mostly based on the use of gas discharge tubes (GDTs) and metal-oxide varistors (MOVs), which are utilised individually or in various combinations. Adequate computer simulations play an important step in the process of designing overvoltage protection systems and selecting adequate parameters. In this paper, the modelling of low-voltage GDT and MOV components is performed using the Verilog-A hardware description language. The presented models are designed for integration with other overvoltage protection system components to form an integrated overvoltage protection system. The current–voltage characteristics of the GDTs and MOVs are highly nonlinear and frequency dependent. The developed Verilog-A mixed behavioural and structural models of GDTs and MOVs ensure a stable convergence of numerical processes during the simulations of circuits with these elements. The simulations of overvoltage protection systems were completed using a TINA circuit simulator. Two laboratory tests were performed using GDT and MOV components. In the first test, the time responses of the current and voltage on a GDT and MOV serial connection were measured in the laboratory. In the second test, the response of the GDT and MOV serial connection was tested in a power line network environment, where a surge current impulse and power line voltage of 50 Hz existed simultaneously. The dynamic response of the GDT and MOV serial connection obtained through the simulations agrees well with the measurement results.

This paper derives a model of high-voltage overhead power line under fault conditions at low radio frequencies. The derived model is essential for design of communication systems to reliably transfer information over high voltage power lines. In addition, the model can also benefit advanced systems for power-line fault detection and classification exploiting the phenomenon of changed conditions on faulted power line, resulting in change of low radio frequency signal propagation. The methodology used in the paper is based on the multiconductor system analysis and propagation of electromagnetic waves over the power lines. The model for the high voltage power line under normal operation is validated using actual measurements obtained on 400 kV power line. The proposed model of faulted power lines extends the validated power-line model under normal operation. Simulation results are provided for typical power line faults and typical fault locations. Results clearly indicate sensitivity of power-line frequency response on different fault types.

Teleoperation over Internet is an area that is more and more applied and it expands day by day. Reason for this is the great advantage of the Internet as a communication medium (distribution, easy access, low price and so on). However, the Internet as a communication medium has flaws which hinder the development of this area. These are primarily variable communication delay and data loss. This can cause loss of stability of teleoperation system. This problem can be resolved by using the wave variables. However, when wave variables and variable communication delay are used under such conditions, position error appears. An idea for solving this problem is using the correction of position error. A new way of resolving problem for the correction of position error is suggested in this paper by using wave variable proposed by Laurence Bate.

Remote sensing of vital physiological signs allows for unobtrusive, nonrestrictive and non-contact assessment of individual's health. By using video plethysmogram obtained by digital camera recordings of patient's face or hands, health parameters such as heart rate, respiratory rate and heart rate variability have already been investigated. In this paper, time-domain video plethysmogram from forehead was used for calculation of pulse transit time, which is related to blood pressure. Synchronous measurements of non-contact video plethysmogram, 12-channel electrocardiogram and invasive blood pressure were performed on three subjects. Our results demonstrate that pulse transit time method can be equally efficient with non-contact VPG signal, with error mean and standard deviation of 9.48 ± 7.13 mmHg and 4.48 ± 3.29 mmHg, for systolic and mean arterial pressure, respectively. Additionally our findings show that delay in pulse transit time, calculated from two different VPG signals from forehead and palm, could provide clinically useful measure of changes in systolic blood pressure.

—Ubiquity of natural disasters during last few decades have risen serious questions towards the prediction of such events and human safety. Every disaster regardless its proportion has a precursor which is manifested as a disruption of some environmental parameter such as temperature, humidity, pressure, vibrations and etc. In order to anticipate and monitor those changes, in this paper we propose an overall system for disaster prediction and monitoring, based on wireless sensor network (WSN). Furthermore, we introduce a modified and simplified WSN routing protocol built on the top of the trickle routing algorithm. Routing algorithm was deployed using the bluetooth low energy protocol in order to achieve low power consumption. Performance of the WSN network was analyzed using a real life system implementation. Estimates of the WSN parameters such as battery life time, network size and packet delay are determined. Based on the performance of the WSN network, proposed system can be utilized for disaster monitoring and prediction due to its low power profile and mesh routing feature.

The study about a cost effective topology based on the single wavelength bi-directional multiplex is conducted. In this study the Capital Expenditure (CAPEX) from point of view of payback period is analyzed, and a cost-effective novel FTTH (Fiber to the Home) scheme based on the single wavelength bidirectional multiplex is proposed. By using the proposed schema it is possible to reduce initial CAPEX and at the same time to reduce a payback period for new FTTH networks. The proposed schema allows achieving an increase in capacity of 50% in existing FTTH P2P (Point to Point) network.