Dear readers and colleagues,

recent advances in engineering and computers sciences opened new horizons for interdisciplinary research. The cooperation of experts from engineering and life sciences has already proven to be very beneficial and several important achievements are pushing area of biomedical research forward. Some of the biomedical systems and application have already found applications others are under development showing huge potential for the future. This special issue presents several contributions from different areas of biomedical research and provide indication of recent advances in biomedical engineering.

Several classification methods have been widely used in literature for identification of diseases or differential diagnosis of various types of disorders. Classification methods such as support vector machines, random forests, AdaBoost, deep belief networks, K- nearest neighbors, linear discriminant analysis or perceptron are probably the most popular ones. Even if these methods are frequently used there is a lack of comparison between them to find better framework for classification. In this study, we compared performance of the above mentioned classification methods. The 10-fold cross validation was used to calculate accuracy and Matthews correlation coefficient of the classifiers. In each case these methods were applied to eight binary biomedical datasets. The same evaluation was realized also in conjunction with feature selection technique that passed only hundred most relevant features. Even though there is no single classification method that dominates in terms of performance, we found that some methods provide more consistent performance than others.

This article describes the hardware design of four-channel amplifier (BioAmp) for human neurophysiologic electrical activity measurement. Variable combination of leads is possible depending on the measurement type and characteristics thereof. Gain of individual leads is adjustable via digital potentiometers. It is possible to measure various types of biological signals such as ECG, EEG and EOG. The application of simple brain – computer interface (BCI) using BioAmp device is presented in the paper. The non-invasive Steady State Visual Evoked Potential (SSVEP) method is used for this purpose.

The software described in this study allows the analysis of heart rate variability, a relatively new method for evaluating autonomic nervous system functioning. Analysis of heart rate variability is based on time-domain methods and methods of nonlinear dynamics. The software provides an array of tools for quick and simple analysis of the autonomic nervous system parameters. We aimed to study complexity and time asymmetry of short-term heart rate variability as an index of complex neurocardiac control in response to stress using symbolic dynamics and time irreversibility methods. ECG was recorded at rest, during and after two stressors (Stroop, arithmetic test) in 70 healthy students. Symbolic dynamics parameters (0V%,1V%,2LV%,2UV%), and time irreversibility indices (P%,G%,E) were evaluated. Correlation analysis revealed no significant associations between symbolic dynamics and time irreversibility. Concluding, symbolic dynamics and time irreversibility could provide independent information related to alterations of neurocardiac control integrity in stress-related disease.

Interaction of extremely low frequency (ELF) electromagnetic fields (EMF) with human has been a great concern over the previous years for researchers. ELF EMFs emanating from high voltage transmission lines interact with human by inducing electric fields internally in body. Various studies have shown the ill effects of this interaction on human organism. In this paper, numerical calculations of internally induced electric field and current density in human of different gender and age are done. Maximum values of external electric and magnetic fields are estimated from the detailed survey carried out on 132 kV high voltage transmission line. Human body is a complex structure comprising of several tissues with varying values of conductivity and relative permittivity. It is very difficult to describe the interaction of external fields with every single tissue and no direct method is available for measurement of internally induced fields. Internal fields are estimated with the help of homogeneous ellipsoid model. The total induced electric field and current density due to combined effect of external electric and magnetic field is calculated. Results obtained are compared with recommended exposure levels.

Currently, several systems for Intrusion Detection System (IDS) management exist, however they are suffering from numerous downfalls; the fact they mostly focus on the visualization of gathered data and not on the management itself (which is, in fact, the critical part) being the main one. The goal of this work is to develop a solution for IDS management that would simplify the usage and provide greater efficiency when detecting intrusions, thus providing the overall improvement of the system security. This article concerns about the analysis of current IDS solutions and their management tools, the architecture of our solution and the evaluation of the solution based on this architecture. The expected results improve the efficiency of an IDS system and also of the whole system security itself.

The article deals with the possibilities of movement control of a five-joint robot manipulator, which is composed of Dynamixel actuators. It contains a description of sending user-defined data, which are stored in individual addresses of the actuators’ control unit. According to these data, the actuator is able to change the parameters of movement, such as velocity, dynamics of acceleration and deceleration, accuracy of reaching a specific position, etc. The article also compares the settings of individual parameters.

The possibility of dynamic energy storage such as auxiliary function FACTS regulator offers to control flows of active and reactive power in an attachment point to the system. Dynamic control of active and reactive power is running independently from each other. Reactive regulation power provides voltage control and network stability with a huge dynamic response. Integration possibilities of energy storage in a chemical form into the storages, has a potential to bring significant advantages for the transmission operators and distributional networks. Increasing distributed share production, which is based in part on the renewable energy sources, leads to the storage need for some needs that offer ancillary services and allow reliable, cost – effective and quality electricity supply. In this paper, we present a method which allows to keep the optimal amount of SoC. deal with SoC level balancing (to 50%) by identifying Active Frame (AF), Frame of Charge (FoC), Frame of Discharge (FoD), SoC deflection predictions and its balancing with as little DoD cycle change as possible.

In the article, mathematical model of simple camera by the perspective projection is described. Furthermore, two base techniques of stereoscopy scanning of 3D visual scene are described. The first technique is a stereoscopic system with parallel optical axes and the second technique is stereoscopic system where optical axes of cameras are crossed in defined point. From these mathematical constructions equations for spatial coordinates estimation of 3D objects in 3D visual scene are derived. Afterwards, a simulation for different parameters of individual stereoscopic camera systems is performed. Based on the results of simulations, features of both stereoscopic camera systems are analysed.

Arrayed waveguide grating (AWG) is very attractive device for the all optical networks. This paper is devoted to the principle of AWG, the advantages and drawbacks of AWG. The problems of AWG were described and the decisions of these problems are resulted as well.

In this paper, we describe a new numerical method for Preisach distribution function identification. This approach is characterized from other identification methods published in the literature by the use of few experimental data extracted from first magnetization curve(usually provided by the manufacturers). In order to entirely discretize the Preisach triangle, the new method uses a cloud of points created and positioned in (H-M)-plane with respect to the experimental data. Mathematical developments revealed a parameter denoted λ used in the positioning and whose variation affects significantly the magnetic properties. Numerical simulations performed for different values of this parameter have shown its great influence on the hysteresis loops shape. Comparisons of the obtained results with experimental data allowed the identification of the λ factor as the ratio of the magnetization at the bend saturation to the magnetization of saturation. The efficiency and applicability of the developed method have been tested through numerical simulations and comparisons with available experimental data.

Synthesis of analogue circuits, most commonly achieved by heuristic methods. In this paper we show that the circuit topology used in the development of what semi-automatic and automatic options available. In this article we'll show also how the many alternatives we can reduce the number of attempts, to make the process more efficient. Method described in this article illustrates the applicability of the solution using a simple example. This approach may be important later in the digitally configurable programmable analog circuits (FPAA) analog synthesis system perspective. The switch matrix as described by using the chances of these circuits may be extended.