automatica
M. Hadjiski. Does Automation Become a Routine Engineering Discipline

Key Words: Artificial intelligence; automation; control theory; knowledge.

Abstract. During the second half of the twentieth century Automation was doubtlessly one of the most dominant scientific and engineering directions. In control theory a number of original concepts with a fundamental importance received a quick and deep development – dynamic systems, feedback, stability, modeling, identification, optimization, robustness, controllability and observability. These new concepts rendered a strong interdisciplinary paradigmal impact on a variety of scientific areas of advanced activities – computer science, decision making as well as on classic sciences like neuroscience, psychology, medicine, economics, education and many others. On the other hand contemporary Automation absorbs in a natural way lots of relevant achievements in other scientific directions like the fuzzy logic, the approximation theory, the neural nets, the network approach, learning, elements of the artificial intelligence, etc. But during the last fifteen years there was an obvious decrease of the verbal attendance of the Automation problematics in societal debates about the emerging challenges in a globalizing world. In the present paper it is argued that Automation continues to be a solid reactive and proactive factor in the formation of the societal strategy and in the running advanced technological and scientific policy because: (i) Automation speeds up its internal advanced development solving new emerging problems, (ii) Automation possesses relevant tools to predict corresponding scientific challenges and to Overcome Them, (Iii) Automation Will Be Together With Artificial Intelligence The Most Powerful Action In The Social Digitalization In The Near Future.

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automatica
G. Mihalev, H. Stoycheva. Synthesis of a Linear Quadratic Controller for Vibratory Bowl Feeder

Key Words: Vibratory bowl feeder; LQR controller; robust analysis.

Abstract. In this paper, a synthesis of the LQR control unit for a vibratory feeding and orientation module is presented. The device representing the control object is considered as a two-mass resonating system. In the presence of parametric uncertainty, a linear model of the system in state space is produced. A robust closed-loop analysis has been accomplished, showing the robust quality and robust stability of the system provided by the LQR controller.

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automatica
E. Mihailov, K. Boshnakov, I. Petrova. Risk Assessment of Liguid Steel Breakout in Metallurgical Ladle

Key Words: Risk assessment; liquid steel breakout; metallurgical ladle; infrared thermography.

Abstract. In the present paper is considered the risk assessment for liquid steel breakouts from metallurgical ladle. The damages with different form are investigated. Mathematical models for geometric dimensions of damages and temperature field on metallurgical ladle are created. The temperature field is measured by infrared thermo camera.

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automatica
N. Deliiski, D. Angelski, N. Trichkov, Z. Gochev. Computation of the Average Mass Temperature of Wood Details during their One Sided Heating

Кey Words: Average mass temperature; oak details; one sided heating; plasticizing; bending.

Abstract. An approach for computing the average mass temperature of the wood and the rate of its change during one sided heating of flat wood details, has been suggested. The approach is based on the use of the solutions of own non-linear model for the calculation of the non-stationary 1D temperature distribution along the thickness of subjected to one sided conductive heating flat wood details aimed at their plasticizing in the production of curved back parts of chairs. A software program has been prepared in the calculation environment of Visual FORTRAN Professional for solving of the model. With the help of the program, the 1D non-stationary temperature field in flat oak details with an initial temperature of 20 oC, moisture content of 0.15 kg.kg-1, thickness of 12 mm, 16 mm, and 20 mm during their 30 min one sided heating at temperature of 80 oC and 120 oC of the heating metal body has been calculated. After integration of the temperature field, the average mass wood temperature and the rate of its change of the subjected to one sided heating oak details has been calculated. The obtained results are graphically presented and analyzed.

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informatics
E. Otsetova-Dudin, I. Kurtev. ModSecurity Rules for Web-Server Protection

Key Words: ModSecurity; HTTP; OWASP; Web Application; Firewall.

Abstract. The security of the information in the contemporary dynamic and information world is by priority importance. Every day the entire world alarms for different in their nature and object hacker’s attacks. The damages of those attacks are as well fiscal and moral. The most popular attacks against the web-applications are those with causing service denial (Denial of Service – DoS), the blocking of the functioning of different sites or entire systems. Protection opportunities of web-servers, functioning in real time of OWASP (Open Web Application Security Project) are presented in that material. The module ModSecurity provides a set of protection rules, based on control of the ingoing and outgoing traffic from the point of view of the server

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informatics
K. Dimitrov. Analysis of the Information Security in WLAN Standards IEEE 802.11

Key Words: Wireless LAN (WLAN) security; WEP; RC4; IEEE 802.11; IEEE 802.1X; IEEE 802.11i; WPA; TKIP; WPA2; AES; CCMP; KRACK attack.

Abstract. On the basis of extensive research in the specialized literature, a critical analysis of information security protocols in the standards for IEEE 802.11 wireless LAN (WLAN, WiFi) has been carried out. Finally, some conclusions and recommendations are made. The first WLAN security protocol – WEP is extremely insecure and should not be used. Due to the inherited vulnerabilities of WEP and the fact that some parts of TKIP (such as the Michael function) have some security deficiencies, WPA has already exhausted its role as a temporary WEP fix for legacy hardware and is not recommended. Despite the mathematically proven cryptographic security of the AES standard in CBC mode, a weakness in the cryptographic key management process makes it vulnerable and leads to a security breach of WPA2 in October 2017. Although the vulnerability is removable by patch, probably a lot of WiFi-Devices have not been updated, which puts users at risk. In addition, despite updates of the firmware and recommendations from information security professionals to circumvent and/or block the protocol breach, reports emerged in October 2018 that the vulnerability to KRACK was still being exploited.

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achievements and applications
V. Dimitrov, L. Popov. Identification of Significant Movement Parameters of Trains Powered by Electric Locomotive Series 45

Key Words: Moment of inertia; resistance force; braking factor; running qualities.

Abstract. In the railway transport practice it is important to maintain sustain control of speed mass, resistance and braking capability of the railway composition. The mass control issue is of great importance especially when in case of transportation of liquid on rail as the liquid leakage will instantly be established using mass control. The resistance control during motion is also a priority as thus we will be able to establish the moment of derailment due to resistance increase. It is important to control the braking capability of the train composition as it enables the engine driver to receive continuous information and if problem in the braking system occurs to take the appropriate action.

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