Approach to optimizing charging infrastructure of autonomous trolleybuses for urban routes

P u r p o s e s. When designing a system of urban electric transport that charges while driving, including autonomous trolleybuses with batteries of increased capacity, it is important to optimize the charging infrastructure for a fleet of such vehicles. The charging infrastructure of the dedicated routes consists of overhead wire sections along the routes and stationary charging stations of a given type at the terminal stops of the routes. It is designed to ensure the movement of trolleybuses and restore the charge of their batteries, consumed in the sections of autonomous running.The aim of the study is to create models and methods for developing cost-effective solutions for charging infrastructure, ensuring the functioning of the autonomous trolleybus fleet, respecting a number of specific conditions. Conditions include ensuring a specified range of autonomous trolleybus running at a given rate of energy consumption on routes, a guaranteed service life of their batteries, as well as preventing the discharge of batteries below a critical level under various operating modes during their service life.M e t ho d s. Methods of set theory, graph theory and linear approximation are used.Re s u l t s. A mathematical model has been developed for the optimization problem of the charging infrastructure of the autonomous trolleybus fleet. The total reduced annual costs for the charging infrastructure are selected as the objective function. The model is formulated as a mathematical programming problem with a quadratic objective function and linear constraints.Co n c l u s i o n. To solve the formulated problem of mathematical programming, standard solvers such as IBM ILOG CPLEX can be used, as well as, taking into account its computational complexity, the heuristic method of "swarm of particles". The solution to the problem is to select the configuration of the location of the overhead wire sections on the routes and the durations of charging the trolleybuses at the terminal stops, which determine the corresponding number of stationary charging stations at these stops.

Choosing a video conferencing service and its adaptation for educational institution

Objectives. The authors aimed to demonstrate the need for implementation of video conferencing service into the learning process, to select a video conferencing service, and to conduct a computer experiment with the selected BigBlueButton video conferencing service.Methods. The problems of choosing a video conferencing service from the list of video conferencing and video conferencing software are considered. At the stage of software selection, the features of its operation, requirements for hardware and for integration into internal information systems are indicated. Load testing of the video conferencing service was carried out by the method of volume and stability testing.Results. The load graphs for hardware components of the virtual server in the long term period are presented. The article describes the results of the graphs analysis in order to identify the key features of the video conferencing service during the test and trial operations.Conclusion. Taking into account the cost of licensing, as well as integration into the e-learning system, a choice of video conferencing service was made. A computer experiment was carried out with the selected BigBlueButton video conferencing service. The features of the hardware operation of the virtual server (on which the BigBlueButton system is located) have been determined. The load graphs for the central processing unit, random access memory and local computer network are presented. Problems of service operation at the stage of load increase are formulated.

Updating the Earth remote sensing software for the detection of thermal anomalies

O b j e c t i v e s. The task of improving the software package for detecting thermal anomalies based on meteorologicalsatellite data developed by the unitary enterprise "Geoinformation Systems" was solved.M e t h o d s. In the period from 2015 to the present, the work on practical testing and improvement of the software for natural fires detection has been carried out. For this purpose, satellite images of the territory of Belarus obtained from NOAA series spacecraft were used. Special attention was paid to the problem of improving the accuracy of determining the coordinates of fires and reducing the time required for initial data processing.Re s u l t s. A retrospective analysis of the main stages of improving the software for natural fires detection and obtained during practical tests generalized results are provided. The description of the web service developed on the basis of the software for detecting natural fires is presented.Co n c l u s i o n. The information can be useful for the specialists and researchers who are engaged in the detection of thermal anomalies (fires) using remote sensing data from meteorological satellites.

Optimization of the PID coefficients for the line-follower mobile robot controller employing genetic algorithm

O b j e c t i v e s. To develop a control system for the movement of a mobile robot along a color-contrast line, as well as to find the values of the coefficients of a proportional-integral-differentiating (PID) controller that allows the robot to move along the line at a given speed.M e t ho d s. To adjust the values of the coefficients of the PID controller, methods of enumeration, automatic tuning and a genetic algorithm are used.Re s u l t s. A software package for tuning the PID controller of the educational mobile robot RoboCake, designed to move along a closed color-contrast line at a given speed, has been developed. The software package consists of a simulation model of the specified robot in the Simulink environment, several virtual traces-polygons and a specialized solver based on the developed genetic algorithm. With the help of the proposed fitness function, a mobile robot control system that satisfies the stated conditions is implemented. Based on the conducted model experiments, the desired values of the parameters of the PID controller are obtained.Co n c l u s i o n. A comparison of the effectiveness of various methods of tuning the PID controller is carried out. The developed software package is designed to solve the practical problem of moving a mobile robot along a color-contrast line at a speed of 1 m/s. The results obtained can be used to study methods of evolutionary tuning of stabilization systems for transport robots, ensuring their movement without overshoot.

Assessment of the mental fatigue state of an operator influenced by electromagnetic noise radiation

Objectives. The problem of determining the mental fatigue of the operator, which is processing the confidential information under the influence of electromagnetic noise radiation, is solved. The relevance of the problem is associated with the need to process the confidential information by the operator located in the limited space of a mobile technical system.Methods. The methods of spectral analysis theory of the results, received in the process of experimental studies the electroencephalograms, are used.Results. The results of experimental studies were obtained based on the processing and analysis of electroencephalograms recorded in standard leads Fp1, Fp2, F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, T6. The following quantitative parameters have been analyzed: power spectral density of delta-, theta-, alpha-, beta-, gamma-rhythms under the influence of electromagnetic noise radiation.Conclusion. The presence of mental fatigue of the operator is based on a comparative analysis of the obtained results and the data described in the scientific literature related to the occurrence of chronic mental fatigue; the fatigue caused by the military performing simulation tasks; mental fatigue caused by performing an RVP test.

Design of Belarusian and Russian natural language interfaces for online help systems

O b j e c t i v e s. The main goal of the work is a research of the natural language user interfaces and the developmentof a prototype of such an interface. The prototype is a bilingual Russian and Belarusian question-and-answer dialogue system. The research of the natural language interfaces was conducted in terms of the use of natural language for interaction between a user and a computer system. The main problems here are the ambiguity of natural language and the difficulties in the design of natural language interfaces that meet user expectations.M e t ho d s. The main principles of modelling the natural language user interfaces are considered. As an intelligent system, it consists of a database, knowledge machine and a user interface. Speech recognition and speech synthesis components make natural language interfaces more convenient from the point of view of usability.R e s u l t s. The description of the prototype of a natural language interface for a question-and-answer intelligent system is presented. The model of the prototype includes speech-to-text and text-to-speech Belarusian and Russian subsystems, generation of responses in the form of the natural language and formal text.An additional component is natural Belarusian and Russian voice input. Some of the data, required for human voice recognition, are stored as knowledge in the knowledge base or created on the basis of existing knowledge. Another important component is Belarusian and Russian voice output. This component is the top required for making the natural language interface more user-friendly.Co n c l u s i o n. The article presents the research of natural language user interfaces, the result of which provides the development and description of the prototype of the natural language interface for the intelligent question- and-answer system.

Information support for decision making in problem situation description

Objectives. The problem of automating the user information support in decision making system at the stage of describing the problem situation is solved. The relevance of the problem is associated with the need to collect and process significant amounts of information, since in the presence of a large number of factors, a person's capabilities are often insufficient to search and organize the necessary information.When solving the problem of user information support at the stage of describing the problem situation, three main goals are pursued: building a mathematical model of the corresponding processes; formalization of the set of basic concepts of the model; development of the algorithms for implementation of user interaction with the information system.Methods. Methods of set theory, probability theory and graph theory are used.Results. A mathematical model of user information support at the stage of describing a problem situation has been developed. In the process of interacting with the user, the system suggests special templates of sentences and texts for filling. Along with templates, the user receives help texts from the system. They are generated on the basis of the previously developed model of knowledge representation in the form of verbal associations, that is, semantic links between words and phrases corresponding to associative relationships between the entities they designate in the real world.Conclusion. As an implementation of the proposed model, the following algorithms have been developed: an algorithm for creating a dictionary of communicative fragments; algorithms for creating fragment-slot templates for sentences, texts and subject areas; an algorithm of user information support. The vocabulary of communicative fragments is created in four steps in accordance with their formal definition. At each step, four conditions from the given definition are tested sequentially. Fragment-slot templates of sentences are formed by replacing their basic communicative fragments with slots, and text templates - as tuples of templates of their sentences. Fragment-slot templates of subject areas are created in the form of implementation of binary relations reductions on the sets of sentence templates from the corresponding thematic text corpora. Each thematic body of texts defines a certain subject area.

Logical gates recognition in a flat transistor circuit

O b j e c t i v e s. With the increasing complexity of verification and simulation of modern VLSI, containing hundreds of millions of transistors, the means of extracting the hierarchical description at the level of logical elements froma flat description of circuits at the transistor level are becoming the main tools for computer-aided design and verification. Decompilation tools for transistor circuits can not only significantly reduce the time to perform VLSI topology check, but also provide the basis for generating test cases, logical reengineering of integrated circuits and reverse engineering to detect untrusted attachments.The objective of the work is to solve the problem of extracting the structure of the functional level from a flat circuit of the transistor level by recognizing in it subcircuits that implement logical elements.M e t h o d s. Graph based methods are proposed for solving some key problems arising at the stage of structural recognition of CMOS gates in a transistor circuit: partitioning a graph into connectivity components corresponding to transistor subcircuits; recognition of subcircuits that are logical elements, and functions implemented by them; forming a library of recognized gates and constructing two-level transistor circuit. The original flat and resulting two-level transistor circuits are presented in SPICE format.Re s u l t s. The proposed methods are implemented in C++ as a part of a transistor circuit decompilation programfor the case without any predetermined cell library. All steps of the proposed methods of structural CMOS gates recognition are performed in a linear time from the number of transistors in the initial circuit.Co n c l u s i o n. The decompilation program has been tested on practical transistor-level circuits. Experiments indicate that the present tool is fast enough to process circuits with more than a hundred thousand transistors in a few minutes on a personal computer. Currently, the authors are developing methods for recognizing more complex elements in a transistor circuit, such as memory elements.

Monitoring the reliability of integrated circuits protection against Trojans: encoding and decoding of combinational structures

Integrated circuits, systems on a chip are the key links in various industrial systems and state defense systems. The emergence of counterfeit integrated circuits, problems of piracy, overproduction, unauthorized interference in the design of microcircuit, hardware Trojans require the development of methods and means of their timely detection. Trojans can be introduced into the integrated circuits structure both on the development stage and during the production process, including the stages of specification, design, verification and manufacturing. The inclusion of additional elements in the integrated circuits structure jeopardizes the functional suitability and reliability of the system as a whole. For the purpose of hardware protection of projects, the methods of hardware coding are currently used.The paper discusses the features and reliability of logical coding of combinational circuits. An algorithm for cracking the code of combinational circuits is proposed, based on the description of encoded structure by the resolution function and reducing the problem to SAT CNF. The initial data for decoding the structure of a digital device is the structural implementation of encoded circuit, obtained, for example, by reverse engineering (prototype design), as well as an activated physical sample of an integrated circuit, when into protected from unauthorized access memory the correct key value is loaded. This sample can be used as a black box model. The main idea of breaking a key is to solve a problem without research on a large interval of values of input and output variables.

Application of first-order logic to identify organizers and perpetrators of illegal actions in teams of a limited circle of people

There are three main families of inference algorithms in first-order logic: direct inference and its application to deductive databases and production systems; backward inference procedures and logic programming systems; theorem proving systems based on the resolution method. When solving specific problems, the most effective algorithms are those that allow you to cover all the facts and axioms and must be taken into account in the process of inference. An example is considered in which it is necessary to prove the guilt of a person in murder. On the basis of statements, a knowledge base is formed from expressions, with the help of which an expression of first-order logic is compiled and proved using direct logical inference. The proof of the reasoning obtained in direct inference using the proof tree is given. However, direct inference provides for the implementation of all admissible stages of logical inference based on all known facts. The article also considers a method based on the resolution when implementing the reverse inference, taking into account the expression obtained in the direct inference. This expression is converted into a conjunctive normal formula using the laws of Boolean algebra and is proved by the elimination of events using the conjunction operation.