Modelling and simulation of artificial neural networks using software SIMBRAIN

This paper is considered to be a continuation of a previous publication devoted to tendencies in the applications of advanced technology solutions to strengthen the cybersecurity of critical infrastructure (Yearbook Telecommunications, vol. 6, 2019). The specificity of the research is related to tracing the evolution of artificial neural networks (ANN) from their establishment to their modelling and simulation. The theoretical framework involves a well-supported rationale by some practical examples of advanced methods of design and simulation of ANN using SIMBRAIN. These methods are applicable in Cognitive science and Robotics because of their contribution to scientific researches related to study of perceptions and behaviors, abilities of decision making, pattern recognition and morphological analysis and etc.

Specifics of modeling and simulation of the risk on the communication and ensure systems

The aim of the proposed work is to study the characteristics of modeling and simulation of risk on the ensure systems, as specific communication systems. On the ensure systems case of interest is Probabilistic Risk Assessment (PRA). The assessment focuses on predicting the probability of failures that can lead to injury and / or loss of life and / or severe damage to the system and / or environmental damage. The result of PRA modeling is to determine the probability for a particular result, but with severe consequences, and to identify those events or components, which will most likely lead to this result. Risk assessment models are typically use to assess system safety and to decide on resource management to prevent accidents. Results of analyzes performed using analytical models, as well as simulation modeling of risk on ensure systems, under various specific initial conditions, are presented. Based on these results, the peculiarities (advantages and disadvantages), as well as the perspectives of the analytical and simulation modeling, can be seen. Based on the examined examples are illustrated the actual results, related to the principles and peculiarities of the analytical and simulation modeling in the field of the risk assessment in the ensure systems according to the sampling survey.

Questions of the overall dependability of the scada system in the corporate infrastructure

The paper considers the peculiarities of the SCADA (energy infrastructure management system in the railway infrastructure), as well as issues of the overall dependability in the corporate infrastructure, which is the aim of the study. The study, based on the accepted structure and values of the parameters, examines what depends on and how the readiness factor of a SCADA system changes when the recovery intensity changes and at a fixed failure rate. The results show that with increasing recovery intensity, the readiness factors of the telecommunications network and SCADA system thus defined increase, while reducing the downtime. For a more in-depth study of the overall reliability of the SCADA system, it is necessary to set specific normatively accepted dependability parameters of all connected elements, as well as a real set structure. Based on the fact that with backup resources provided, a defined dependability of the system can be ensured at preset values of the reliability parameters of its components and the backup structure; the opposite problem can also be solved. The proposed approach for studying the reliable behavior of the SCADA system within the corporate infrastructure can be noted as a contribution of the present work and conclusions are made for the practical use of the results.

The choice of bachelor’s program in telecommunications and computer technology

The aim of the article is to show the influence of the graduated secondary education for the choice of the bachelor's program "Telecommunications and Computer Technology" from the Telecommunication’s Department, NBU. The article presents some of the results of a survey conducted among students of the bachelor's program. The presented data are for students who started their education during the academic years from 2016 to 2019. As a result of the study, it was found that the students enrolled in the bachelor's program most often have graduated from vocational technical high schools in this field. Together with graduates of other vocational high schools, they are approximately half of the students who choose this bachelor's program.The study will contribute to anticipating the preliminary preparation of students who have chosen a bachelor's program in "Telecommunications and Computer Technology" and to improve their future education.

Approach for analysis and modeling of reliability of network connectivity from the perspective of efficiency and its applicability

Reliability analysis and assessment methods can be used at any stage of system or component design, including development, operation, and maintenance. Fault Tree-based models and reliability block diagram RBD (qualitative and quantitative) are typically used to provide reliability and readiness assessments for both the early and later stages of design, where system models are more -improved and have more detailed specifications compared to the models of the early stage of the system. On the other hand, models based on the Markov Chain are mainly used in the later design phase. The aim of the work is to define ways to use methods for modeling reliability, with a subsequent goal for analysis taking into account the effectiveness. An approach for modeling the end-to-end network connectivity with different reservations of the connection lines is considered. The results are illustrated by graphical ratios at different influencing parameters, for different reservation methods. A comparative analysis was made using different reservation methods. The practical applicability of the proposed approach and the performed analysis, incl. for training purposes.

CGI technologies and methods for 3D scanning – new horizons

The enduring presence of photometric technology and in particular Lidar 3D scanning systems in CGI's technological tools testify to the potential and development opportunities they possess. But here we will focus on another quality of technology. The opportunities they provide for achieving new visual forms by interpreting nature on the basis of basic features. for direct work and manipulation of raw point clouds massif. The reason - a non-standard visual method for interpreting reality offering an extremely wide range of transformations even in the direction of algorithmic structural modeling. In this article, we will analyze both the tools and the technological practices known to us as "technological hybrids".

EMC assassement criteria and interference protection for basic radio services in accordance with ITU-R recommendations

The effect of unwanted energy due to one or a combination of several desired and unwanted emissions upon reception in a radio communication system results in performance degradation, misinterpretation or loss of information. Multiple sources of interference may affect the receiver input: services of the same type or other operating in the same frequency band, services operating in adjacent frequency bands, sources generating continuous or short term interferences, fixed or mobile sources, etc. To prevent such interfering situations, a key element is the standardization of appropriate criteria for electromagnetic compatibility (EMC) and interference protection (IPC). The purpose of the studies and analyzes in this article is to systematize the criteria for electromagnetic compatibility for basic radio services based on the Publications of ITU-R. Criteria for four important areas of radio communications covering fixed, fixed satellite, broadcasting and mobile radio services are compared. Contributions are the categorization of the criteria according to the type of interfering signal and the results of the analyses, which show that the regulatory requirements and practical methods for interference protection and EMC for different radio services differ. Detailed criteria for predicting the probability of interference being standardized only for some radio services.

Impact of Bulgaria’s entry in the euro area for the banking and real sectors in the republic of Bulgaria and in particulary for the telecommunications industry

The publication analyzes the advantages of the entry of the Republic of Bulgaria into the ERM 2 currency mechanism and the banking union. The first part indicates the benefits for our country for the banking sector of the Bulgarian economy, respectively for facilitating the payments of companies and citizens. The second part of the publication refers to the advantages for the real sector of the Bulgarian economy, respectively for the Telecommunications sector. In conclusion, some not very significant shortcomings are indicated, which will occur after Bulgaria's accession to the euro area.

Peculiarities of distributed systems, SCADA and IoT

The aim of the work is to consider and compare the features of distributed systems, SCADA and IIoT. Both SCADA and IoT include sensors and data collection. Although they differ in many respects, they share a common goal. The idea of a smart grid leads to the integration of SCADA and IoT. SCADA is useful for monitoring and managing installations or industrial equipment. The Internet of Things is a collection of physical devices with different implementations, software upgrades, sensors, actuators, and network connectivity, all of which work together to enable objects to connect and exchange data. The focus of the article is the consideration, as distributed systems and in comparative terms, of the development of industrial technologies IoT and SCADA. The presentation will include a summary of the characteristics of these two technologies and a structural-functional analysis of the efficiency in the integration of the latest generations of SCADA systems in the functionality of IoT. The possibilities for integration are shown, as well as the prerequisites for this. The results can be used as recommendations in the areas of design and operation.

Methods and means for digital transformation of physical objects

The research aims to present main methods of digital transformations of physical objects by the means for 3D modelling and 3D scanning. Emphasis is placed on the advantages of laser scanning and the nature of the triangulation methods on which it is based. It is explained how the reliability of the obtained results depends on the calibration process that precedes the 3D scanning of a physical object. Special attention is paid to the technical and software preparation that precedes the 3D scanning process. The practical research is realized using a physical object suitable in terms of construction, shape and size. For the digital transformations is purposefully chosen a real existing spherical robot, which serves as a basis for comparison in assessing the effectiveness of the described methods, as well as the quality and realism of the obtained digital models. The scientific and applied contributions are expressed in a comparative analysis of practical methods, which contains an algorithm of steps suitable for educational purposes for the implementation of the described work processes.