Table of contents

8th International Scientific Conference "TechSys 2019" – Engineering, Technologies and Systems is organized by Technical University of Sofia, Plovdiv Branch. It was held on 16-18 May 2019 in Plovdiv, Bulgaria. The main goal of TechSys is to bring together researchers from academia and industry, scientists and experts in the field of engineering and technologies for sharing the ideas and innovations. Selected articles that represent the significant results of the conference have been collected to publish in this volume.

The conference is organized under the frame of "Science Days of Technical University of Sofia" and supported by the Scientific and Research Sector.

We would like to thank all the authors who have trusted the conference. To thank all those researchers who recognized the TechSys as an appropriate forum to share their recent developments and to get the new trends in the field of technical sciences and engineering.

We must also thank all the reviewers and topic editors for their quiet but very important work, which ensured high quality of scientific research.

Thanks to the plenary speakers Prof. Zezulka and Prof. Bradac for valuable presentation.

Last but not least, we sincerely thank the whole team involved in organizing the TechSys 2019 conference.

Editors: Prof. Valyo Nikolov and Assoc. Prof. Nikola Shakev

TECHNICAL UNIVERSITY OF SOFIA, PLOVDIV BRANCH

8-th INTERNATIONAL SCIENTIFIC CONFERENCE "ENGINEERING, TECHNOLOGIES AND SYSTEMS" TECHSYS 2019

Organizing Committee, International Programme Committee, Scientific Secretary and Technical Secretary are avilable in the pdf.

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

The paper goes out from the state of the art in the area of Industry 4.0 initiative of the most developed countries. There are also discussed reasons of Industry 4.0 development and implementation into existing still developed technologies. According to the last development, the term digital twin became a very often-used word. Authors explain differences in the content of the digital twin and recommend to use for the Industry 4.0 area the more appropriate and precise specified term – the Asset Administration Shell (AAS). Next parts of the contribution therefore deal with the Asset Administration Shell (AAS) in details to enable engineers, technicians and informatics from the praxis much more simple introduction in the Industry 4.0 problems and their solution. There is introduced and explained the structure of the AAS, the model and sub-models architecture, parameters and features in the contribution.

This paper presents a research over application of global thresholding methods for evaluation of cut surface of white cheese in brine. Six trademarks Bulgarian white cheese in brine produced of cow, sheep and goat milk are used for cut surface evaluation. Examined cheese samples are evaluated by experts and the results are used as referent assessment for results of image processing trough thresholding algorithms. A Java program is developed for image segmentation with specific thresholding algorithm using two or three colors in different modes to produce segmented image. The images of cheese samples (their cut surfaces) are processed with developed program using all of the seventeen thresholding algorithms which are implemented in Auto_Threshold plugin for open source software ImageJ in different modes. A correlation analysis shows that some of thresholding algorithms which are implemented in Auto_Threshold plugin could be used for cut surface evaluation of white cheese in brine.

In this paper are analyzed and formulated the main requirements for the drive systems of a class of modernized boring machines with digital program control. On this basis, a methodology for optimal selection of feed drives is offered. The respective algorithm takes into account the specific features of the technological process, the treated material, the tools used and their wear, the mechanical gears types and the guides. Concrete examples with DC and AC electric drives are presented, illustrating the practical application of the methodology. The research held as well as the results obtained can be used in the development of such electric drives for the studied class of machine tools with digital program control.

The realization of the control algorithm consists of two main stages: planning of a joint coordination sequence and implementation of an embedded walking algorithm in the Arduino Mega 2560 hardware platform. The joint coordination sequence consists of 13 steps in order for the humanoid robot to move forward without falling. The embedded walking algorithm is realized around the operating points of the servo motors. The software is developed in Arduino IDE in C language.

The study assesses how two techniques for bias removing influence the parameterization of a humidity sensor model with known structure. Experimental data consist of SHT 31-DIS sensor responses to a step change of humidity from 12 %RH to 65 %RH. The test performed after parameter estimation shows that the time-series subtraction unbiased method produces a model with a better coefficient of determination. This and other results obtained are useful when a data pre-processing for black-box modelling of humidity sensors is used.

This study concerns with the evolution of entanglement in a quantum neural network (QNN) model that is locally in contact with data environments. As a valuable resource, duration of entanglement in quantum systems is extremely important. Therefore, the effect of various initial states on the occurrence or decay of entanglement are examined in the presence of information reservoirs. In this study, central spin model was investigated as a quantum version of neural networks inspired by biological models. The architecture of the model is based on a central spin system with two nodes where the nodes are coupled to independent spin baths. Numerical results show that initial state preparation has a profound effect on the fate of entanglement. The results show that the entanglement lifetime can be adjusted by engineering the reservoir states as well as the initial states of the system of interest. The results can be used to improve the performance of the formation or distribution of entanglement in realistic communication network states.

This article presents the developed algorithm with LoRa specification. Based on it is achieved LoRaWAN for monitoring application in industrial systems. There is no universal solution for using LoRa Media Access, in such cases. The combination of low power hardware and radio communication is an advantage of the work. The developed algorithm ensures a new and modern network structure for monitoring in control systems. The real time observation is conducted in TTN. The experiments verified the algorithm applicability in the frame of systems of new digital industry.

This paper presents the developed trajectory tracking controller for a formation of nonholonomic robots, which combines features from the leader-follower and virtual-structure approaches. The implemented decentralized control strategy allows the robots to be relatively independent and to switch easily between the executed individual tasks and the collective tasks. Convergence is thoroughly analyzed and guarantied using the Lyapunov approach.

Modern enterprises are working in a complex and volatile business environment. In order to adapt to this situation, enterprises are trying to realize horizontal and vertical integration of the enterprise processes (managerial and production processes) leading to the creation of a real-time enterprise. In such an enterprise, integral data is used with different time horizons, starting from the millisecond, generated by automatic devices, and ending with daily, generated business applications. However, these integral data are rarely used for operational management of time by enterprise processes of the enterprise. To overcome this limitation, a process model for identifying and assimilating knowledge is proposed that encompasses four steps: (i) analyzing and (re-designing the enterprise's controlled processes, (ii) developing a data model and enterprise data flow diagrams for automatic devices and business applications, (iii) identification of knowledge based on the discovery of knowledge in working with databases, (iv) continuous monitoring and management of enterprise processes, using complex event processing.

The article is devoted to the development of algorithms and software that automatically recognize road users - pedestrians, build their trajectory according to the analysis of the video stream. The architecture of the system for pedestrian recognition and inter-frame tracking is proposed. The developed algorithms can be used to estimate road situation with participation of pedestrians for the traffic monitor systems.

In unconstrained facial images, large visual variations concerning pose, scale, the presence of occlusions, expressions and lighting usually cause difficulties in discriminating faces from the background accurately. As a result, some non-face regions are recognized as faces (false positive) and that influences the effectiveness of face detection algorithms which is characterized by low false positive (FP) rate, high detection rate and high speed of processing. In order to reduce these non-face regions, they are considered as anomalies and then try to detect them. In this paper, we propose an anomaly detection method using reconstruction error from variational autoencoder (VAE), which is a generative machine learning model. We train VAE to learn reconstructing faces that are close to its original input faces using FDDB dataset, then the difference between the original input face and the reconstructed output is measured to obtain the reconstruction error which can be used as an anomaly score. Consequently, the regions resulting from faces detection algorithm with high reconstruction error are defined as anomalies or false positives.

This paper provides the comparative analysis between two recent image-to-image translation models that based on Generative Adversarial Networks. The first one is UNIT which consists of coupled GANs and variational autoencoders (VAEs) with shared-latent space, and the second one is Star-GAN which contains a single GAN model. Given training data from two different domains from dataset CelebA, these two models learn translation task in two directions. The term domain denotes as a set of images sharing the same attribute value. So, the attributes that are prepared: eye glasses, blond hair, beard, smiling and age. Five UNIT models are trained separately, while only one Star-GAN model is trained. For evaluation, we conduct some experiments and provide a quantitative comparison using direct metric GAM (Generative Adversarial Metric) to quantify the ability of generalization and the ability of generating photorealistic photos. The experimental results show the superiority of cross-model UNIT over multi-model StarGAN on generating age and eye glasses attributes, and the equivalent performance to synthesize other attributes.

In the present work, the application of repetitive filters in the robust process control systems is examined. The functionality of the proposed system and the improved performance, robust performance and filtering properties has been proven.

In this study, lead-free, piezoelectric devices were fabricated by vacuum radiofrequency (RF) sputtering of Ga–doped, ZnO (GZO) nanocoatings at different deposition modes on silicon substrates. Several deposition rates were varied (2 to 16 nm/min) by tuning the sputtering voltage and pressure, in order to control the microstructure and surface morphology of the films. The dependences of the piezoelectric properties of GZO thin films on the different deposition conditions were investigated. Significant dependency of the films' microstructure and surface roughness was observed to the deposition modes used for fabrication. The results showed that after optimization, the surface roughness of the films grown using sputtering voltage 1.1 kV and Ar=2.5.10⁻² Torr, is 6 nm. Films with such microstructures are characterized with crystallites orientation (002) and exhibit the highest piezoelectric coefficient of 96.3 pC/m, which is superior compared to other known, lead-free, piezoelectric materials. A simple, membrane–based, vibration sensor was fabricated at the optimal set of conditions to demonstrate the functionality of the coating in a real microelectromechanical (MEMS) device. The working range of the device is between 2 and 800 g and the piezoelectric voltage generated after minimum deformation of 5.4 nm (2g), was 9.66 mV.

In the present work we have investigated the parameters of peripheral blood flow by using a non-invasive method for processing photoplethysmograms (PPGs). The developed original technique allows us to register a photoplethysmogram, isolate the pulse wave and determine the duration of cardio intervals, the duration of the anacrotic and dicrotic phases, the duration of fast and slow blood filling, the expulsion period, the dicrotic and diastolic indices, temporal and amplitude parameters of vascular tone, etc. We observe three types of photoplethysmograms after taking medicaments Corvitol-50 and nitroglycerin. The analysis of the amplitude-temporal characteristics of PPGs allows the determination of key diagnostic parameters.

Having essential experience and results, concerning Interference Wedged Structures (IWS), we have developed and practically realized optical beam splitter elements as suitably built variants of IWS. The principle of action, theoretical treatment, including computer simulation for optimization is briefly discussed. As an essential point, the technological approach for practical realization of simplest applicable Interference Wedged Based Splitters (IWBS), are carried out. The splitters are built as compact thin flat and plane, practically – sheet-like, elements with dimensions e.g. ∼ 4 × 3 × 0.2 cm. They present advantages as: smooth and linear varying the power ratio between the formed beams by simple sliding of the splitter in its plane; keeping the direction of propagation of the formed beams during the control of their variations; very small losses in splitting (theoretically ∼5 %); work with high power incident beams (kW/cm² and more for CW and MW/cm² for ns pulses beams).

The paper present design of low-cost antenna array for RFID indentification in the frequency range 865 to 868 Mhz. The design antenna has enhanced coverage (pattern) and beam-steering capabilities. It can serve as a base element for more sophisticated RFID readers with direction finding capabilities and improved distance of tag reading.

A family of copper bromide metal vapor lasers used as brightness amplifiers in recently developed optical systems is considered. One of the main problems of this area is to investigate the basic amplification characteristics of the laser medium. In this study, a simplified mathematical model is developed based on the one-dimensional stationary equation for determining the electron temperature of the discharge. The proposed model allows to calculate the radial distribution of the electron temperature of the discharge by taking into account the radial distribution of the supplied electric power. Computer simulations are run to investigate the dependence of electron energy as a function of the electrical power supplied to the gas discharge tube. The natural limits of this process are specified.

Atmospheric pressure plasma pretreatment based on dielectric barrier discharge technology at industrial frequency (50 Hz) has been used for surface activation (oxidation, functionalization) of four species of European and tropical wood samples in a multi-step plasma enhanced capillary process of flame retardancy. Plasma-chemical activation is an effective surface alteration by attaching polar or functional groups to wood and cellulosic surfaces. Oxygen containing functional groups enhance effectively capillary impregnation processes for flame retardation of wood as porous media finishing. Oxidation level was studied by wettability in order to follow the increased surface free energy. For each species, a critical active power surface density was necessary to obtain the best impregnation results more quickly. The relationship between the penetration-spreading parameter and the active power density has been investigated experimentally as process quality parameter.

The article presents the determination of the short-circuit currents in distribution networks with trilaterally power supplied branches – form a supplying substation and two decentralized energy sources. After connecting decentralized energy sources, branches with bilateral and trilateral power supply appear. This changes the network configuration and, respectively, its mode parameters, and also requires adjustments to the settings of the relay protection.

The paper studies an electromagnetic harvester, consisting of a Π-shaped plate with 4 magnets, placed on two springs, rigidly fixed at their low end. A coil lies between the magnets. Modeling by means of ANSYS has been done and the horizontal deviation of the mechanical system has been obtained. The magnetic field of the electromagnetic harvester has been modeled by Femm and its electromotive force has been defined. Experimental studies have been conducted for validating the developed model.

The paper considers two piezoelectric harvesters, consisting of two springs, attached to a piezoelectric transformer, and having a common concentrated mass. Modeling has been done by means of ANSYS, whereas the horizontal deviation of the mechanical system has been obtained, and the charge, accumulated on the electrodes of the piezo plate has been calculated. An equivalent circuit has been drawn and experimental studies have been conducted in order to validate the developed model.

The paper presents an approach for determining the equivalent circuit parameters of two widely used induction motors types by Genetic Algorithms. The T-shaped equivalent circuit without considering the steel losses is utilized. Genetic Algorithms are applied and the results are compared by using one, two and three data sets. The accuracy of the proposed approach is analyzed by determining the relative error in the parameters, obtained by Genetic Algorithms, with regard to analytical values. The different computation times for one, two and three data sets are discussed. The results indicate that to obtain low relative error, the proposed approach using the conventional parameters settings and fitness function needs three points from the motors load curves.

The paper proposes methods for enhancing the accuracy and speed of Genetic Algorithms when determining the parameters of induction motors. A systematic study of the impact of genetic operators and algorithm parameters on optimization process performance is done. New fitness functions are developed containing additional quantities such as the input power of motors. Various genetic operator types and constraints are analysed providing an insight into a specific settings choice. Special attention is given to the factors generating stochastic noise and the ways to eliminate it. To evaluate the effectiveness of the proposed fitness functions and parameter settings, ten combinatorial optimization experiments are conducted on two types of induction motors. The results show that adequate fitness functions, combined with proper genetic operators setups, can significantly enhance the accuracy and speed of Genetic Algorithms while reducing the required input data.

The paper presents an experimental setup and a method for determining the contact resistance between busbars at a given contact force. Experiments have been conducted by means of an experimental setup, developed for the purpose of studying the influence of the contact force on the contact resistance between busbars with cross-sectional area of 60x6 mm. The study has been performed for two types of bolted connections, complying with DIN 43673, which have been studied for both copper and aluminum busbars.

The paper presents the results from studies of both the active and reactive power of a wind power plant, connected in parallel with a high power electrical grid. The wind power plant is with SCIG asynchronous generators and a step-up substation 21/115 kV, realized by means of cable lines. The analyses have been made with the help of a computer model, synthesized in MatLab environment. The dependencies of the power, the power factor and the phase angle on the mechanical moment of the generator shaft in the cases of only one generator operating and all generators operating have been obtained. The inductive reactive power for compensating the capacitive power of the wind plant has been calculated at turned off generators. The parameters of the inductive compensating reactor have been determined. The capacitive power for compensating the inductive reactive power has been defined at loaded generators.

This report presents a study of connection between winding distribution and some current limiting devices parameters. Influence of separation coefficient on the variation of the mass parameters and the active resistance of an air coil is examined. The results of the simulation study are presented and a critical analysis is performed.

The antibacterial action of Ag-doped Al₂O₃ nanolayers, deposited by RF reactive magnetron sputtering on hard contact lenses, was established. Synthesis of Ag/Al₂O₃ protective coatings is necessary for suppressing the infections caused by pathogenic microorganisms following the placement of hard contact lenses. The chemical composition, morphology and optical properties of the coatings were studied. Microbiological studies conducted of the nanocomposite Ag/Al₂O₃ layers against Gram-positive and Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus) proved their antibacterial effects. Intense action of the layers was found against Pseudomonas aeruginosa - full inactivation after 2 hours; Escherichia coli - full inactivation after 5 hours; Staphylococcus aureus – full inactivation after 24 hours. Our experimental findings suggest a very promising application of such antibacterial Ag/Al₂O₃ nanolayers regarding the reduction of eye infections when the hard contact lenses are used.

This paper presents the system for the continuous monitoring of the physiological state of the vehicle driver. The developed system allows to make adequate decisions and forecast the situation on the basis of the driver fatigue monitoring data. Identification of drowsiness, state if carried out on the basis of blinking duration and frequency analysis. The neural network is used to detect blinking patterns. Signal acquisition and processing are performed on the wearable multisensor microcontroller-based device.

Application of the Portfolio theory to appreciation of the Bulgarian stock exchange following the most popular financial indices is presented. The data of these indices corresponds to the same watching periods an year before. Comparison of the optimization problem's solutions and analysis of the financial activities are commented. Modification of the portfolio optimization problem is proposed for calculation facilitation.

Wireless networks are widely used with increasing number of users. Typically, they are based on the IEEE 802.11 standard (Wi-Fi). Because of its broadcast nature, they are very susceptible to security attacks. It is very important to study the risks and potential vulnerabilities of Wi-Fi networks, which will allow defining recommendations for users to enhance their security. This paper presents a methodology and research of the security of wireless networks in Varna city based on war-driving technique. The obtained results are analyzed and compared with those from previous research. The recommendations are given.

With the development of computational science and computer simulations, the randomness source has become a necessary part of every complex system and testing environment. Most programming languages, software frameworks and application libraries do not provide all different types of randomness generators and do not even implement high-quality algorithms for secure data generation. This paper presents an object-oriented solution for providing all the main classifications of randomness via random data generator classes that offer frequently used formats in information technology and in statistical hypothesis testing. It also presents usages for secure data generation and confirms the importance of true randomness in cryptography. The purpose of the developed practical experiments is to evaluate and show the differences in the sample generation quality of the sub-classifications of software randomness generators using the developed object-oriented components.

Health information technologies have the potential to advance healthcare delivery and assist patients and providers in achieving better outcomes. While development and adoption of electronic health records (EHR) already have reached high levels, health information exchange is still a challenge. This paper presents some of the basic terms and concepts in the domain. The lack of standards and security concerns are discussed as the main technical barriers for reaching integration and interoperability. Mobile technologies are described as a new source of data and promising tool for providing personalized care. Latest trends and solutions are presented, as well as the need of advancement.

This article presents the results of the authors' work on a project of the European program Erasmus+ "Diversification of seafarers' employability paths through collaborative development of competences and certification" – DivSea. In this project, the Nikola Vaptsarov Naval Academy is actively involved in partnerships with related maritime education institutions from Romania, Cyprus and the Netherlands. The aim of the project is introducing qualifications required by the marine labour market into the European education and training institutes to ensure transparency and recognition of skills and qualifications to facilitate learning, employability and labour mobility. Transferring the aim to the shipping, we propose to use modern ship communication equipment and computer technology to enable seafarers to access up-to-date training and qualifications at any point in the World. The created and developed training programs by the participants in the project fill the gap created by the rapid development of shipping over the last twenty years and the changes in maritime legislation in this regard. The opportunities for ship Internet delivery at every point of the world ocean are used. These communication technologies enable the training of marine professionals to become an ongoing process.

The article presents a frame model for conceptual description of a subject area by presenting a detailed structure of multiple objects and concepts, knowledge about them, hierarchies of types, rules, specifying classes and relations between them. Include all possible words and word combinations that formalize a subject area. The model itself represents knowledge and reflects the conceptual basis of the organization of the memory of a person, as well as its flexibility and visibility. When creating an appropriate database of accumulating frame models (AFM), frame questions, and at a later stage a frame model for automatic question generation, it is necessary to build an appropriate structure that allows for both flexibility and easier building of the databases of data, as well as efficient retrieval of different types of information when summarizing the results. The publication is part of a study devoted to the application of frame models for the presentation of knowledge and processes in e-learning.

The paper describes the design of an intelligent system for smart shopping. The proposed prototype of the system incorporates speech enabled intelligent agent, beacon-based technology, holographic technology, picture exchange communication system, and machine learning techniques. Common use of these technologies in united intelligent systems enables people with different communication possibilities to navigate in large buildings. Some initial user opinions for the system are presented.

The functioning of the modern society provokes creation of significant number of documents, most of them in text form. Many of them are legally relevant and complex in nature, which makes their understanding difficult. They are written in nature language for people, which is hard for computer processing and hence hard for further analysis. Documents represent an abundance of data in unstructured form. They can be handled using NLP methodology. Different models, trained for specific use cases are used, depending on a type of legal document. Automation of number of processes can save time and speed up work on document processing. This, of course, does not rule out the need for highly qualified lawyers. The goal is to ease their work in terms of processing large amount of documents. Increased productivity should be beneficial for both natural and legal persons when working with textual and legal issues.

As the era of the Internet of Things (IoT) is emerging rapidly, the interference problem is also increasing at the same pace. In IoT based connections, as we know that devices share a common communication channel to interact with each other, the interference problem arises as all the devices are connected. Once an attacker gains access to any of the devices in an IoT enabled network, the whole IoT network becomes susceptible to breach. The biggest example of it is the IoT enabled CCTV hacking. In this work, we are proposing the usage of Virtual Private Network (VPN) and Wireless Sensor Network (WSN) to create a virtual environment and to protect each device from IP address breach that is connected to an IoT network. Using VPN, each IoT device will gain their own virtual environment which will enable it for using a dynamic IP address to connect to another IoT device's virtual environment. Using WSN, the virtual environments will be able to identify any signal interference that can cause any security breach.

The software defect prediction is the most operative research domain in software engineering as it enhances its reliability. The availability of defect data related to different projects leads to cross project defect prediction an open issue. This paper instanced on multiclass/multinomial classification of defect prediction on different categories of cross projects. The ensemble learning statistical models – Random forest and Gradient Boosting are used for classification. An empirical study is carried out to determine the predictive performance of the within project and cross project prediction models. Depending on the number of defects, class level information is classified into one of three defined multiclass. The homogeneous set of object oriented metrics is used for training the model. Furthermore, k-fold cross validation is done to evaluate the training accuracy of the statistical models. Major outcome of the paper concludes that multinomial/multiclass classification is applicable on cross project data and has comparable results to within project defect data with statistical significance.

This article is to show an algorithm for assessing the quality of service in special-purpose networks, regardless of the type of traffic being transmitted and the network architecture. This method allows to obtain a detailed assessment of the quality of service, as well as to adjust the values of the characteristics of the network during the evaluation. The values used in the calculations are entered in the database to aid in the design of new networks.

This paper discusses the concept of the Internet of Things. It analyzes the existing definitions, and introduces a new definition of this concept. In this research study, the experience of the Internet of Things in the world has been analyzed, the possibilities of deflationary development of the economy have been identified with the use of the Internet of Things. The paper presents directions for important qualitative changes in economy and for organizational and technological transformations of production, which may be induced by the development of the Internet of Things. The "smart home" system market has been examined. Its potential has been identified for Russian companies that work in the field of information and telecommunication technology connected with the development of the Internet of Things. To justify the efficiency of money investments into the "smart home" system and services, the algorithm of cost estimation for such systems, which can be used in making a decision about investing, is proposed. The authors conducted the review of the typical projects offered with the "smart home" system. The power law dependence of the unit cost of the system installation from the floor space of the object has been received. The internal rate of return on investment for the introduction of the "smart home" system has been identified at the level of 50%.

Due to the lack of the exact mathematical processes description for internal faults diagnosis of synchronous machine rotor winding. To solve the problem of concurrent processing of the indirect diagnostic signs complex connected with the concrete type of multiple disabilities. It is the author's opinion that such problem is necessary to solve by artificial intelligence systems accepted in the theory and practice. The architecture of intelligent diagnostic system and the technical condition forecast of the synchronous machine rotor winding on the basis of the fuzzy logic mathematical tool are offered. Diagnosing reliability of and selectivity support determination of synchronous machine rotor winding defect category is reached by complex conjugation of separation of diagnostic information sensitive methods on the basis of intellectual digital signal processing methods. It is proved experimentally that the fuzzy logic using provided diagnosing reliability of synchronous machine rotor winding turn-to-turn short-circuit at the 1,5% level of rotor pole winding Visualization of all making decision stages about the existence and defect type was made in Fuzzy Logic Toolbox software package.

The paper presents a pilot study on the influence of cold indoor environment on the activity of the brain while solving mental tasks. The Neuro Sky Mind WaveTM technology was used to record EEGs during the cold exposure in two subzero environments. Tsai-Partington test was used to stimulate the brain activity during the state of thermophysiological comfort and during the cold exposure. The results obtained showed differences in the type of the emitted brain weaves and the total brain power used during the same activity in the cold.

In this article, a kinematic analysis of articulated forklift truck turning has been made. Articulated steering systems separate the vehicle into a front and back sections, with a pivot (articulated) point directly joining them in the middle. This allows them to be rotated one compared to the other. In most cases, the turning of the vehicle is accomplished when force is applied to front section, via hydraulic cylinders thus creating torque in the articulated joint or directly applying torque via electric/hydraulic motor. This allows such vehicles to have greater manoeuvrability and flexibility compared to the conventional forklift trucks making them preferable in the modern warehouses, which allows reduction in its isle width and as such increase in the its overall capacity which is of utmost importance. The minimum width of aisle and junction allowing articulated forklift truck with set dimensions to properly pass are been evaluated.

In this paper the strength calculations of a flat wagon are presented. These calculations are carried out in accordance with European standards, but in practice, often, calculations and tests are carried out by a shortened procedure not in accordance with the standards. On the other hand, the procedures prescribed in the standards do not always cover all aspects of the actual operating conditions. Based on the satisfactory results of the calculations, the notified body often admits the wagon into service. Under real working conditions it is established that the structural integrity of the wagon underframe is impaired due to loads not clearly reflected in the standard and are therefore not taken into account either in the calculations or when the wagon is admitted into service. Some activities have been done in order to reinforce the problem areas and a repeated extended strength analysis has been carried out with the loads not described in the normative documents. Subsequently, after the reinforcing measures had been taken, the wagon was admitted back into operation. A proposal for specification of such problems in the European standard EN 12663-2: 2010 is given.

The current work presents the problem of assessment of the material fatigue in the welding area of the rail bogie frame type Y25LS-K. During the assessment process of the bogie frame dynamic strength, it was found that the results from the theoretical assessment differ from the experimental ones. An analysis of the reasons for these differences was made. A few approaches for the theoretical assessment are presented in order to match the conditions for application of the prescribed loads in calculations as close as possible to the test conditions. Proposed methodology allows the commissioning of bogies into service only based on a theoretical assessment of material fatigue in the welding areas of the bogie frames. The methodology is verified in real theoretical and experimental studies of the certified design of bogie Y25LS-K, produced by Transvagon AD, Burgas. The methodology can be used by researchers, performing a stress-strain analysis of the bogie frame as well as by the notified bodies responsible for the admission of those products into service.

The application of Physical Vapor Deposition (PVD) hard coatings is one time-tested practice in the modern industry. Two of the main tendencies that promise a progress in this area are the combination of more chemical elements in one coating and the creation of nanolaminate structures. Since many combinations are possible in the design of the coatings, it could be expected they would have many different properties which are difficult to predict. In an attempt to work simultaneously in both of these directions, one nanolaminate Ti/TiN/AlTiSiN/(AlTiSiN/TiAlSiN)n/AlTiSiN coating was developed and its mechanical properties were tested. The results obtained give a reason to believe that it could be widely practically applied.

This paper presents a newly developed system for mechanical testing at static loading. The separate modules of the system are described - tensile testing machine, grips, extensometers for axial end transverse deformations, electronic control system. The results obtained during tensile testing with the new system are given. The yield strength, the tensile strength, the elasticity modules and the Poisson's ratio of general purpose steal S235JRC are determined.

The paper presents Computational Fluid Dynamics (CFD) based design of a densely populated classroom with mechanical ventilation. The aim is by means of numerical simulations to define the proper locations of four four-way ceiling fancoils in order to provide controlled conditions of the thermal environment in the classroom under summer conditions. CFD simulations are completed by Fluent 6.3 software package. Cooling loads through the enclosing surfaces of the room and the material properties of the modeled elements are evaluated by established and approved methods in the field of HVAC engineering.

The process of hardening a hypereutectic aluminium-silicon alloy AlSi18 in unmodified, modified and nano-modified state has been studied. Two types of modifiers have been used - a standard modifier P, introduced into the melt by means of the ligature CuP 0,4wt.%, and a nanomodifier (nanodiamonds - ND) 0,1wt.%. The influence of the various types of modifiers on the process of crystallization, as well as on the size of the primary Si crystals in the structure of the alloy and their distribution in it has also been discussed.

Reflected noise from traffic barriers usually leads to increasing of the noise level excited by the automobiles and trains. This effect requires the design of transport noise barriers for effective noise reduction behind them as well as to produce small level of reflected noise in source direction. This will effect in better noise environment for many passengers especially in case of busy traffic in rush hours. People affected by this effect are usually far more than the affected ones behind the barrier. One of the existed solutions is the use of expensive combined noise barriers with high degree of absorption. In this study a new passive transport noise barrier is designed, tested and analysed for a good reduction level of the reflected noise. It is done by appropriate design of the barrier profile performing source and reflected acoustic waves interference in small volumes near the barriers. The barrier construction, made by repeated, equally profiled elements, allows even the existence of acoustic bandgaps especially behind the barrier.

The increase of the efficiency of technological processes during the various stages of product development, such as design and manufacture, is in direct connection with their informational support. In this paper are considered the state of the art of modern informational support of processes, and the methods of its realisation. On the basis of informational modelling of technological processes, are considered and analysed the capabilities of the suggested scientific approaches for the assurance of the parameters of its efficiency, including their evaluation. Established is the necessity of a new approach during the modelling of technological processes for parts manufacturing, which would enable to overcome the main problem of their development – the ambiguity of the values of the technological parameters and their influence on efficiency. In order to guarantee the efficiency of these processes, formulated are the tasks and approaches which are to be applied for developing a reliable and up-to-date informational system.

This research deals with the problem of developing a design and technological documentation for a new product in terms of technological processes selection, according to the list of components from the product specification. Practical experience in the implementation of automated control systems in manufacturing enterprises of the machine-building industry and the latest technologies in the field of machine learning were used. The concept of using machine learning for automating the selection of technological processes was developed based on a list of components. As a technique of machine learning, the methodology sequence to sequence is proposed.

The paper deals with mathematical modelling and qualitative analysis of a dynamic system of the type mass-spring-permanent magnet. The mass of the system is suspended on the free end of a cantilever beam and oscillates in a magnetic field created by a permanent magnet. The the magnetic force is obtained using the finite element method and approximated by a function similar to the Coulomb's Law. The dynamical model of the system is built on the basis of the Newton 2^nd law. By means of qualitative analysis of a nonlinear differential equation, the bifurcation zones are determined. The phase portraits of the system are investigated depending on its bifurcation behaviour. Based on the performed analysis a method for dynamical synthesis of system parameters is proposed. Besides, some typical properties of the dynamical system are determined.

The article offers an original method for determining the constant DC/AC motor power range and basic technological parameters of the main spindle unit for multifunctional machine tools at the design stage. The method allows them to be determined, both in terms of the strength characteristics of the gearbox (or the strength characteristics of the system "machine-equipment-tool-work piece") and in order to obtain the maximum spindle torque needed to ensure maximum machine productivity. The graphical interpretation of the method can be used both for designing new and for operating existing machines.

Green time period optimization is essential issue about delay time reduction at signalized intersection. The features of traffic flows are variables in rush and other period of day. Optimal values of green time are that guarantee minimum of delay time. It can be accepted that the values that guarantee that in rush period is can be use in others periods of day. The main issue is being considered in paper is green time period optimization at signalized intersection for minimum delay time according to traffic flows features in rush period. That include comparison between three options of movement diagram and two option of phases for the chosen intersection in Town of Pernik. The application of result will make a lot of benefits both for the traveling and for the environment.

Rubber insulators are used in many dynamic systems to reduce the impact of vibrations. They are located in the mount system of the engine, gearbox, suspension, et cetera. Two of their characteristics are the dynamic coefficients of stiffness and damping. These characteristics are influenced by the frequency of vibration, the preload in the mounts and the hardness of the rubber. The characteristics of the rubber insulators in the suspension elements also influence the handling of the vehicle. In the work are investigated rubber insulators from different suspensions in the frequency range 70 - 220 Hz. This frequency range contains the resonant frequencies of the radial type pneumatic tyre due its interference with the road surface. The purpose of the work is to develop a method for obtaining the dynamic coefficients of stiffness and damping of the rubber insulators.

The current scientific research aims to present two of the methods, which are used worldwide by the automobile expert practice when investigating the velocity of motor vehicles. These methods are based on theorems from mechanics. Basic quantitative characteristic of energy loss during a two-body impact is the introduced in the impact theory – coefficient of restitution (COR). In reference to automobiles, the values of the coefficient depend on the type of the elements that have crashed as well as on the relative velocity in the meanwhile of the crash. The article presents an approach for determining the values of the above mentioned coefficient when investigating frontal or side collisions of vehicles in a movable barrier, based on multiple regression analysis. The conducted research uses real automobile expertise data from the case law.

The study purpose a methodology based on Sequential Interactive Modelling for Urban Systems (SIMUS) method for ranking the urban transport technologies. The methodology of research includes three steps. The first step defines quantitative and qualitative criteria for the assessment of urban transport modes. Fourteen criteria of four groups, as ecological, economical, technological and social for evaluating the transport alternatives in urban environment have been defined. The second step includes a selection of alternatives of transportation by different transport means for a given route. In this research is investigated transportation by metro, buses and cars. The SIMUS method is applied in the third step for ranking the variants of transportation. The method solves successive scenarios formulated as linear programming. This step involves the ranking of alternatives and choice of optimal type of transportation. The methodology is approved for study the alternative mode of transportation for parallel routes from Sofia's transport network. It was found that the carriage by metro is the best transport technology for investigated route. The methodology and defined criteria could be applied to study the transport alternatives for different routes of Sofia's transport network, and also to assess the modes of transport in urban area of Sofia or other city.

The study proposes a methodology based on the combination of Strengths-Weaknesses-Opportunities-Threats (SWOT) analysis and Multi-Criteria Decision Making (MCDM) methods for selecting the most appropriate location for establishing an intermodal terminal. Analytic Hierarchy Process (AHP) and Preference Ranking Organization Method for Enrichment of Evaluations (PROMETHEE) are the MCDM methods used in the paper. The methodology contains four steps. In the first step we determine the alternatives variants of the location of intermodal terminal. In the second step the SWOT analysis have been applied to identify strengths, weaknesses, opportunities, and threats related to the surveyed system. The sub-criteria for each SWOT group have been defined. A total of 33 criteria are included in the study. Third step includes determination of weights of main criteria and sub-criteria by applying AHP method. The results of weights given in this step are used in the four step to ranking the alternative variants of the intermodal terminal location by using PROMETHEE method. The methodology has been approved for choosing the location of intermodal terminal in the city of Ruse. Five alternative locations of intermodal terminal have been studied. The results show that main importance of SWOT group has the strengths group criteria (0.471). It was found that the internal factors including the strengths and weaknesses have more important compared to the external factors including the opportunities and threats when studying the location of intermodal terminal. It was found that the main importance of all sub-criteria have the quantity of manipulated containers (9%), connectivity to road infrastructure (6%), rail connection with a port (5%) and average useful length of railway tracks used for loading/unloading activities (5%). The study shows that location that is situated in the place of the suspended Ruse-East railway yard is the best alternative for intermodal terminal location.

This paper presents research a determining the velocity and the duration of the travel via developed intelligent system of License Plate Recognition cameras and by using the method of recording the State Control Number (DK number) with the aim of improving the traffic organization and safety, as well as reducing the harmful impact and improving the ecological indicators in the research area. The intelligent system for recording and recognition of registration numbers provides the opportunity for statistical analysis to determine traffic performance and to take specific measures so as to improve the organization and increase the traffic safety. It is based on MySQL database and PHP scripts to solve the analysis tasks.

The paper discusses the problems related with the synthesis of a linear quadratic (LQ) regulator of a semi active vehicle suspension. The synthesis combines the control through output variables with such by the input excitation i.e. classical LQ regulator with Compensator. The physical nonlinearities of the controllable magneto-rheological semi-active damper are taken into an account with the including in the feedback control circuit an inverse damper model. . A reduced suspension model is used to illustrate the synthesis (quarter car model).

The present paper evaluates the pros and cons of three different methods of detail design of parts for light aircraft: a conventional (heuristic) method, topology optimization and morphogenesis. This is done through applying these methods to solve the same design problem and analyze the results theoretically by means of finite element analysis under certain external loads. The theoretical results are compared to experimental using Digital Image Correlation (DIC) technique on real parts with the same loads applied. As a case study a control surface A-frame hinge similar to the lower rudder hinge of M-540 aircraft is considered.

When two spaces of different gas pressure are connected through a nozzle forming and spreading a gas jet with certain energetic characteristics is observed in the region of the lower pressure. If a solid body is located in the region of the jet spreading, then this case is defined as an impinging gas jet. The aim of this work is to consider a specific case of this heat transfer method using 3D virtual simulation models known as Computational Fluid Dynamics - CFD. The simulations were performed in the commercial solver Star-CCM+ version 6.04.014 using two turbulence models: Shear Stress Transport - SST and v²f Low-Reynolds Number (Re) k-ɛ model. The obtained results are represented by a dimensionless Nusselt number (Nu) and its local validation determines the accuracy of the solver when using a digital twin describing a real measurement set-up with known empirical measurements in digital format.

This work proposes an improved algorithm for determining the critical speeds of car's movement with low and ultra-low profile tires in a turn, where sliding of its axles occurs and overturning. The critical speeds are determined by the characteristics of the lateral slipping calculated for their critical normal loading. On the basis of the algorithm an interactive programming system in the MATLAB environment is developed. Graphic dependencies for the radius of the turn are presented, taking into account the slip of the tires with different speeds of a car Honda Civic Aerodeck 1.5iLS with low profile tires of size185/60R14. Results have been obtained on critical speeds against sliding in the front and rear axles and against the car's overturning. Critical speed against overturning are determined in the absence of normal reactions for the inner steered wheels in a turn. The critical speeds of sliding are found to be lower than the overturning, and thus appear to be decisive.

The paper discusses the contradiction influence of system damping coefficient in the different excitation's frequency diapasons on the raid comfort and the vehicles stability on road. It is analyzing the discrete "on-off" control laws for the semi-active suspension included in a model reduced to the vehicle wheel and accounting the vertical dynamics of the vehicle so-called "Quarter car model". Based on analysis of the frequency characteristics it is propose a frequency modulation of the control realized by a signals filtration.

The paper discusses obtaining of a control law of semi-active vehicle suspension realizing compromise between requirements for ride comfort and vehicle stability on road pavement. The problem is solved as multi-objective synthesis based on a selection from the Pareto set of the optimal compromise solution by using the Game theory's strategy.

A concept of the air jet engine of mixed type, which combines the operating principles of detonation engine and traditional ramjet, is proposed. A part of inflow that has the smallest losses of the stagnation pressure at forming shocks in the inlet is burned in the combustion chamber of that device. Another part of the inflow, that has the smaller stagnation pressure, has the significantly higher temperature at the same time. Due to this fact, it can be effectively used as in the detonation engine.

This paper discusses the problem of creation of control algorithms when working in the Third Party Logistic concept. It considers the process of supply management when several means of transport and an intermediate distribution center are used. It is assumed that goods are processed in the Machine-to-Machine mode by means of machine-readable codes. The controlling server processes the data and makes a decision either to use one or another mode of transport, or to store the cargo temporarily at the distribution center. An option is provided when an emergent stock of a limited y is placed directly at the end point so that the impact of market uncertainty in demand can be mitigated. The methods of mathematical modeling in the time of uncertainty of the operational environment are applied. The algorithm is based on the stochastic programming method. The practical focus of the work lies in orienting the results on multimodal logistics, which makes the model scalable. The computations, which use the algorithms developed in the paper, provide commercial network managers with a convenient tool for planning current activities taking into account market uncertainty in all operations, when dealing both with consumers and suppliers throughout the business chain, including distribution centers as independent nodes of machine-to-machine interaction. The implementation of the proposed models not only will bring economic benefits and reduce the global traffic, but will also help improve the environment and give a significant social effect.

Optimization of the collaboration "business-science-education" is a prerequisite for the increase of the competitiveness of the enterprises. The article introduces a scientific solution of a practical problem through the creation of a model for informal education of specialists in the wine industry. The presented models are a part of the Virtual Educational Space (VES) as a smart space, context-dependent, based on a script and a controlled infrastructure. The results of the approbation of the model prove its significance for the practical processes and the increase of the competency of the specialists in connection to the implementation of innovation. Particularly to the wine industry, the suggested model for informal education represents a specific innovation, which approbates the known "good practices" in the strategy "Lifelong Learning".

Every business organization faces a crisis at a certain point in its development. Crisis phenomena for overcoming preventive measures can lead to serious economic and social problems for the organization or its bankruptcy. The crisis is a widely held view and its indications affect different aspects of the financial, social, spirit life of the nation. It's important to accent not only to the consequences of its manifestation but also to the opportunities for overcoming. This study focuses to analyze the specific models for assessing the dangers of crisis in Bulgarian enterprises. The report aims to systemize the methods and models for assessing the crisis in the enterprises from different sectors of the Bulgarian economy and to define the specific influential factors on them. A questionnaire was used to collect data from a sample of 312 entreprises which were selected through stratified random sampling method. Collected data were analyzed using descriptive and inferential statistics with the aid of Statistical Package for Social Sciences (SPSS). The study revealed that in the food industry is used Altman's five-factor Z-score while in the enterprises from the financial sector, telecommunications and the IT sector the Springate model is used. Tourism businesses, those in the education sector, and chemical and health enterprises prefer to predict crises through Toffler's model. The results show that crises are somewhat the driving force behind the creation of innovation and are a prerequisite for the emergence of modern forms of entrepreneurship so necessary to stabilize the economic system.

The highly competitive environment for the food industry after the accession of Bulgaria to the European Union puts companies under conditions where the focus is on the quality and products'safety. Both the competitiveness theory and the topic of food safety have been widely discussed in recent years, and research in this area is growing, but there is a lack of in-depth information in the Bulgarian literature on the relationship between competitiveness ↔ food safety systems and the open question of how strategies food safety would increase corporate competitiveness. Examining this relationship, it is possible to uncover those factors stemming from the requirements of food safety systems, the improvement of which can help the food industry companies to increase their competitiveness. The subject of the study is the different approaches and methods of assessment and analysis outlining the opportunities for increasing the competitiveness of enterprises from the food industry through the implementation of food safety systems. The report aims to reveal the interrelationship between competitiveness and food safety systems and the implementation of methodologies to increase their competitiveness. The study and assessment of factors to improve the competitiveness of food business enterprises through the implementation of food safety systems is based primarily on expert judgment as well as on marketing and diagnostic analysis. Emphasis is placed on factors that arise from the requirements of food safety systems and a few extras that are important for the formation of strong competitive advantages.

The processes of global reorganization make managers pay attention to environmental safety and regulation of economic systems. In modern conditions, it is possible to solve environmental problems only by accelerating the development of economic activity. An entrepreneur who seeks to improve competitiveness and becomes a leader, both at the international and national levels. This happens when the company's management implements environmental programs related to financial activities and trade.

The report examines the reasons for turning business models into digital ones and reveals their nature and technological trends. The authors try to point out what are the first concrete steps in the company practice for digital transformation of business models. Based on our own research, the level of digital maturity of small and medium-sized industrial enterprises in Bulgaria.

The report justifies the need to investigate the motivation profile of high-tech enterprises in order to use adequate motivational tactics and techniques in order to have satisfied and committed workers. Different views are given, as well as the author's position on the nature of the motivation profile. Based on own research, conclusions are drawn on the relevance of the motivational factors, the level of satisfaction and commitment from these factors. Specific guidelines and recommendations are given on how to use the motivation potential of the considered factors.

This paper gives a brief overview of the conditions, approaches and prospects of production control and monitoring of manufacturing industry through implementing information systems for optimizing the manufacturing process and to provide an answer to the question of the specificities for successful management of machine manufacturing enterprise through integrated software solutions. New integrated IT solutions based on the newest business management trends and information technologies that includes tools for management of the production and materials, as well as inventory planning, allocation of production resources, process analysis and production organization leads to improvement of the efficiency of business management and production management processes in manufacturing.

The article explores the game as a method that can be used to conduct surveys with children using the possibilities of Internet in an entertaining manner. An empirical survey of children's opinion based on the method of games has been presented. The description of the method by which a study is conducted is in terms of the psychological techniques that have been used, mainly the psychology of colours.

The interaction of urban science with psychology, biology, ecology, and technology creates a rich diversity. Thermodynamics and information theory are among the methods of analysis used to understand urban systems. These methods have a variety of options, and their decision-making processes are complex. Definitions related to the concept of city vary depending on the approach of social science disciplines such as urban science, sociology, geography, economy and public administration. Geographic Information System (GIS) enables the creation of interactive maps of the urban system's transformation processes. Thus, city maps have gained qualifications for the examination of the possible changes and future scenarios. The relationship between city and thermodynamics has been developed with implementations such as energy, sustainability, system approach, spatial analysis, aesthetic evaluation methodologies, urban growth, and urban models. The thermodynamic interpretation of implementations provides concrete data such as heat map of the cities, and energy potential. The interpretation of entropy at the intersection of thermodynamics and information theory gives different perspectives to the concepts such as coding, redefining aesthetics and urban growth. The studies which relates urban issues and entropy concept are very different in approach and content from each other. This situation has also created a ground for meaning shifts. The aim of this study is to critically discuss the methods, concepts, and theories of urban studies related to the thermodynamic terms. As a method, the studies on the approaches of the concepts of thermodynamics in urban planning and urban design will be evaluated with a literature review.

The article examines the challenges associated with designing and delivering effective training. The authors propose the use of serious games in learning (in particular gamification) to achieve higher motivation in learners than traditional e-learning. Pedagogical approaches, theories and pedagogical models, suitable for the design and construction of gamified e-courses are presented and analysed. A plugin is presented for creating gamified e-courses in a Moodle e-learning environment. The plug-in can be used to automatically transform a standard e-course into a gamified one or the initial creation of a gamified course. It is shown how standard Moodle environment elements can be used in game contexts.

The paper is devoted to the task of determining the role of ICT as a part of business intelligence in improving wealth as the resultant factor in the development of the country and society. The authors consider the development of the wealth concept in a historical retrospective. The role of information and technologies as a part of business intelligence in the development of countries has been studied and generalized, digital transformation has been identified as the leading factor in ensuring the country's economic growth. The paper presents data on the development of the digital economy for the period from 2010 to 2016 in developed countries and analyzes the state of the digitalization process in Russia. The authors put forward and test the hypothesis about the impact of ICT as a part of business intelligence on the Human Development Index, which determines the level of the country's wealth according to the current concept adopted in the world community. The results of the research in Russia showed that there is a close relationship between the HDI as a result of the wealth indicator and the majority of indicators characterizing the virtual - digital environment - the Internet, computers, global virtual networks and mobile communications. In conclusion, the paper presents promising directions for further deeper analysis of revealing the degree of influence of each of the identified indicators, as well as the possibility of improving the country's wealth based on the identified role of ICT as a part of business intelligence.

Bio-based products can have a lower environmental and climate footprint than products based on non-renewable raw materials. There is a high potential for the production and use of renewable raw materials for industrial applications, notably the use of lignocellulose from agricultural and forestry residues, industrial crops, by-products/co-products and waste. New low-carbon, resource-efficient and sustainable value chains can be set up using this agricultural and forestry biomass to produce bio-chemicals, biomaterials and bioenergy. These chains will contribute to the diversification of the rural economy and the reinforcement of the industrial base. It will create rural growth and employment, and will help to meet energy and climate policy targets for 2030. This paper aims to study the role of digital entrepreneurship as an essential factor to increase the creativity and innovativeness for sustainable growth of Bulgarian bio-based economy. The results show that socially responsible behavior of the digital enterprises can provide added value based on a favorable reputation that they create.

This study analyses the main factors influencing the development of companies in dairy industry. Particular attention is paid to technological innovations by exploring two groups of companies: applying membrane-cell technology and without applying it. The study has successfully used tools of production functions to determine the total factor productivity in microeconomics. It is determined the impact of technological innovation on overall factor productivity and corporate growth.

The production of elongated shaped charges is particularly dangerous (or in the language of ISO 9001 "special") and difficult from the point of view of quality control, so it is necessary to pay special attention to the dynamics of customer requirements, the level of development of competitors in order to remain a competitive organization. The proposed work addresses the issues of determining the ways of product development based on the analysis of the dynamics of consumer requirements and the level of competition, a mechanism is shown to identify bottlenecks of products based on the results of the organization's resource audits.

The publication presents the results of a study of the process of investing in the innovation of the Russian manufacturing industry (sample 2009-2017). Factors of economic efficiency of investment projects of the industry are revealed. It is proved that the efficiency of investment is determined by external factors, primarily by the level of economic concentration (CR3) of the market of innovative products. The coordination of the scientific result with the industry consolidation dynamics model (A.T. Kearney) is presented.

This article describes a study of parameters of a comprehensive assessment of the organization's information security. The formation of a knowledge base based on international and national standards and various industry requirements is proposed. Based on the standards, methods for filling the knowledge base for the expert system and a model for the functioning of this system are proposed. As a result, with a help of a specific user interaction algorithm with the output mechanism, it is possible to segregate the industry component in information security assessment process that will allow more accurate identification of risks and making recommendations for protection.

To inquire aims of diversification as the most important Russian enterprises resultatives increase mechanism, the article considers scheme of enterprise functioning in diversification motives and aims interconnection and executes analyzing firm activity character change with its diversification and character of financial impact on its diversification. Analyzing particular diversification aims has allowed considering threats and negative factors, obligate to taking into account in forming enterprise activity diversification strategy to taking into account its specialties. Forming enterprise activity and financial sustainability basic assessing figures ordered graph and considering their calculation formulas has allowed modeling this graph. Practical realizing modeling enterprise activity diversification and financial sustainability basic figures ordered for a research object – St-Petersburg oil-gas machine-making enterprise taking into account presented graphic interpretation of its financial condition shows this research practical sustainability and opportunity to spread into other industries. The elaborated graph is the basis to form economically-mathematical models and algorithms of defining several kinds of enterprise's credits. Besides that, it is one of effective instruments of complex economic analysis, which is the base of backgrounding potential enterprise development destinations with statistic modeling enterprise production process parameters. Therefore, elaborated graph practical realization helps to sufficient increasing effectiveness of managing enterprise.

A steady trend of the development of modern processes in human activities (social, economic, bioengineering, medical, technological) is a complication of the tasks, which are to be tackled on different levels of administration. This is connected with growth of amount of inconsistent information, necessary for well-grounded decision making, as well as with time saving for decision making. To improve the quality of decisions taken in these conditions, intellectual decision-making systems and artificial intelligence methods, on which the procedures for the direct preparation of solutions to various tasks are shifted, are increasingly being used. The article deals with the fundamentals of the structural organization of functional hybrid intelligent decision-making systems designed to solve difficult formalizable production and economic tasks, and suggests a new cognitive approach in the development of integration and effective management of formalized and weakly formalized knowledge in decision-making systems.

This article presents a control model of security management systems from destructive software and hardware effects. Considered descriptive and analytical control model of security, presents the structural and logical scheme of a control model of security management systems from destructive software and hardware effects, carrying out the search and elimination of conflicts, associated with the logical inconsistency of the structure of the control system, and conflicts associated with ongoing processes, i.e. with the fulfillment of the tasks of the regulations, operating in the system. It is proposed to realization the model, using the language of radical schemes, based on the stand for providing integrated developments. The model integrates with mathematical means of searching, predicting and eliminating conflicting schemes in the system.

The publication presents the results of a study of the process of investing in the innovation of the Russian manufacturing industry (sample 2009-2017). Factors of economic efficiency of investment projects of the industry are revealed. It is proved that the efficiency of investment is determined by external factors, primarily by the level of economic concentration (CR3) of the market of innovative products. The coordination of the scientific result with the industry consolidation dynamics model (A.T. Kearney) is presented.

Let K be an arbitrary field, whose characteristic does not divide the order of the dihedral group D_2m of order 2m, where m is odd. In this paper we examine the structure of the semisimple dihedral group algebra KD_2m . For this purpose, we find a complete system of minimal central orthogonal idempotents of the group algebra. Through it we define the minimal components of KD_2m and its Wedderburn decomposition. The results we get are as general as possible, i.e. without requiring the field to be finite.

For considered class of nonlocal boundary value problems for mixed type PDE of arbitrary high order an implicit symmetrizing operator [2,4] is built. Equivalence of the problem to the problem of minimization of appropriate quadratic functional is proved. Existence and uniqueness of the generalized solution in variation sense are obtained.

Using optical and SEM microscopic observations and EDX analysis, the corroded surfaces of AZ91, AM50 and AE42 Mg-alloys in 3.5%NaCl were studied at condition of open circuit potential. Different surface composition, morphology, density and characteristics of the surface films were established. The corrosion potential, recorded for 5 days in the case of AE was studied and specific behaviour was observed. EDX analysis established the presence of Mg and Al in the corrosion products of the three alloys and Ce for AE42 and formation of oxides and/or hydroxides of these elements was assumed. A mechanism of dissolution of Mg alloys at OCP condition in NaCl solutions was discussed.

This work presents the results of corrosion inhibition of aluminium alloy EN AW-2011 in 1M HCl environment by Rosmarinus officinalis, using gravimetric and gasometric techniques. The inhibition efficiency increases with increasing the concentration. The investigation showed optimal inhibition efficiency of about 62%. The results confirmed that the adsorption of Rosmarinus officinalis reduces the corrosion rate of this alloy in the acidic medium.

In this work, we performed experimental and numerical simulation of gas flow in the model of the open cell foam filter. We investigated the relationship between the porosity of the medium ɛ, and the parameter Po characterizing the number of pores per inch. We obtain a porous medium from the inverse matrix of the computational model made on a 3D printer. The calculation results of the pressure drop depending on the average filtration rate correlate well with the experimental data. Particle trajectories make it possible to determine the particle deposition efficiency in a porous layer for three values of the porosity of the medium ɛ = 0.6, ɛ = 0.7 and ɛ = 0.8 . The deposition efficiency in the case of porosity ɛ = 0.8 correlate well with the data obtained by the semi-empirical formula of the authors of [1], however, for the other two values of the porous medium, the efficiency curves differ significantly, so the dependence was obtained for a material with high porosity. We define the filter quality parameter by the ratio of the particle deposition efficiency to the pressure drop value in the porous layer.

We built a mathematical model and carried out a numerical simulation for the reaction of isoparaffins dehydrogenation in a fluidized-bed reactor using the example of dehydrogenating isobutane to isobutylene. Experimental data determine the parameters for the construction of the model. Numerical studies with the choice of the average diameter for the polydisperse catalyst were conducted. We performed the calculations for cases of the monodisperse and bidisperse composition of particles, carried out the analysis of the influence of the fine particles present on the reaction product yield in the numerical simulation.

The research work presents the results of mathematical modeling of the ethylbenzene dehydrogenation process to styrene in a fixed catalyst bed. Calculations for the different length granule packaging are carried out. Calculated values of the reaction product yield (styrene) are in a wide range of gas velocities. There are significant differences in the yield of the product at high gas velocities for catalyst granules of different shapes. Of the considered catalyst granules forms, we got the best yield efficiency by the use of granules, which provide maximum surface area and porosity in the fixed bed catalyst.

The effect of temperature and concentrations on the stability of anthocyanin extract from aronia as pigment and sinapic acid as copigment was evaluated. Different temperatures and copigment concentrations were used for the investigation pigment:copigment interaction. Equilibrium constant of copigmentation process was determined. Thermodynamic parameters Gibbs free energy (ΔG), enthalpy (ΔH), entropy (ΔS) and kinetic parameters activation energy (Ea) and z – factor were calculated. At high temperatures, around 80 °C destruction was observed and after that at 25 °C, restoration of the complex was observed again according the calculations. This was conformation for reversibility of copigmentation process.