ON ALGORITHM FOR DETECTING CHANGES IN THE OBJECT MOTION MODE

The article deals with the solution to the problem of determining the motion mode of an object along a complex trajectory. A hybrid stochastic model is used to describe a complex trajectory. The solution of the problem is based on the application of a sequential decision rule about the choice at an unknown time of the hypothesis about the current mode of motion, with a limited size of the bank of competing Kalman filters. An algorithm is constructed for calculating the average size of the Kalman filter bank in the case of M-possible motion modes. The algorithm is developed in a general form, therefore, it can be used not only for the four types of object motion models considered in this paper, but also for any linear discrete-time models with Gaussian noise presented by equations in the state space. The algorithm for a priori estimation of the average size of a bank of competing Kalman filters for M-possible modes of motion is implemented in MATLAB, the results of computer simulation are presented.

CONSTRUCTING AND IMPLEMENTING SOME PERFECT VERIFIABLE SECRET SHARING SCHEMES

Most of the existing public key cryptosystems are potentially vulnerable to cryptographic attacks as they rely on the problems of discrete logarithm and factorization of integers. There is now a need for algorithms that will resist attacks on quantum computers. The article describes the implementation of Shamir’s post-quantum secret sharing scheme using long arithmetic that can be applied in modern cryptographic modules. The implementation of the Pedersen – Shamir scheme is described, which allows preserving the property of the perfection of the Shamir scheme by introducing testability. The article presents graphs reflecting the influence of the verifiability property in the Shamir secret sharing scheme on the speed of its operation.

CONTROL OF A GROUND MOBILE ROBOT MOTION IN CASE OF THE NAVIGATIONAL DATA CORRUPTION OF THE SATELLITE NAVIGATION SYSTEM

The article discusses the determination of navigational data corruption, which received by the satellite navigation system as well as traffic control of ground mobile robots. It also specifies the movement features of ground robots, which affect the data integrity monitoring. It proposes an algorithm of control to implement the methods of autonomous onboard monitoring of the navigational data integrity. The algorithm is based on the equations of signal correspondence in various parts of the control system. It is designed to determine the inoperability of the satellite navigation system that implies the loss of signal and failure in the navigation problem solution. The algorithm takes into account the non-deterministic nature of moving ground robot with possible stops in the process of following the trajectory. The article considers the implementation variants of algorithm to assess reliability for the control system containing additional sensors of the robot’s displacement and for the hardware-redundant system containing no additional sensors. The results of modeling the movement of a ground mobile robot along an arbitrary trajectory in case of navigational data corruption are presented. The features of algorithm based on the simulation results are described in the article. The authors considered variants of robot control in case of navigational data corruption. The structure of the system and a method for controlling a mobile robot in case of satellite navigation system failures are also proposed. The method is based on the control mode in the system, according to the measured data of the position of the robot in the case of navigational data corruption or otherwise according to the data calculated from the robot model. The implementation of the method makes it possible to avoid significant deviations of the robot from a given trajectory of movement at intervals of signal loss of the satellite navigation system.

THE PARADIGM OF NEURAL NETWORK DECODING OF NON-BINARY REDUNDANT CODES

The use of noise-tolerant coding in modern communication systems remains the only means of increasing the efficient energy of such systems. This parameter tends to increase in conditions when the receiver of the communication system is able to correct errors of a large multiplicity. At the same time, the existing experience of using various methods for decoding the received data to achieve such a goal in the format of algebraic or iterative procedures does not give a noticeable effect and leads to a large time cost and an exponential increase in the complexity of implementing the decoder processor. The reason for this situation is the passive position of the receiver, which, when processing each code vector, remains a fixator of the picture that occurred in the communication channel and, in general, by compiling a system of linear equations and then solving it, tries to identify the error vector. Some exceptions are permutation decoding systems, which, by selecting and using reliable characters from the number received at the reception, simulate the operation of their transmitter and compare the received (almost error-free) result of such encoding with the received combination [1, 2]. With the growing influence of destructive factors, such methods are ineffective. A natural question arises: are modern solutions in neural network technologies capable of improving the characteristics of code vector recognition systems in order to obtain acceptable machine time costs in order to achieve an increase in the energy characteristics of communication systems.

INTEGRATION OF THE MEASURED ALTITUDE-SPEED PERFORMANCES IN THE SYSTEM

The air data system used by modern aircrafts is a soft hardware designed to measure, compute, and display the altitude-speed performances as well as other parameters such as air temperature, angles of attack and slip; and to provide to aircrew and consumers (various on-board systems) with this information. The speed and altitude are one of the most important flight parameters of an aircraft. The operating principle of modern onboard equipment for measuring the aircraft movement parameters while in flight is based on an aerometric method. This article deals with a method for increasing the accuracy and the reliability of aerodynamic angle-of-attack measurements.

THE QUALITY CONTROL OF PLATED-THROUGH HOLES OF PRINTED CIRCUIT BOARDS BY PULSED LASER HEATING

The article gives a brief overview of standard methods of quality control and defect diagnostics of plated-through holes (PTH) of printed circuit boards (PCB) and considers their main disadvantages. It scrutinizes the methods of thermal control, which are reduced to PTH heating and monitoring the temperature. The main disadvantage of common methods is that they require a contact during heating the PTH and temperature measurement, which leads to significant errors and low reliability of control. The article describes a non-contact method involving heating only one side of the PTH by a laser beam and non-contact temperature measurement of the PTH ends by an IR camera. The authors propose a thermal equivalent scheme of PTH to analyze the transient thermal processes in PTH, which takes into account the heat removal from the plating of PTH into the PCB material. It is shown that the quality of plating can be estimated by the temperature difference between the upper (heated) and lower ends of the PTH, and the quality of adhesion between PTH plating and the PCB material can be estimated by the ratio of temperature increments. The article describes peculiarities of this method and gives the results of its testing on a real sample.

THE ALGORITHM FOR EVALUATING GRAPHICAL USER INTERFACES BASED ON THE SEARCH TIME OF INFORMATION AND FUNCTIONAL OBJECTS

The article deals with the problem of the quality of graphical user interfaces used for various software products. The indicators for evaluating the quality of interfaces are analyzed. A formalized approach to evaluating the speed of information search and functional objects is formulated. An algorithm for evaluating the speed of information search and functional elements is proposed, which allows automating the process of evaluating and comparative analysis of interfaces of various programs.

OPTIMIZATION OF PARAMETERS OF GENERALIZED DISPERSION ALGORITHM AT STATISTICAL PROCESS CONTROL

When monitoring a real production process using statistical methods, the question of early detection of violations arises. In most cases, several indicators are monitored simultaneously in the production process, and a change in the values of some indicators leads to a change in others. If there is a dependence of indicators for their monitoring, multivariate statistical control tools are used, in particular generalized variance chart. By varying the parameters of the chart, its efficiency can be significantly increased, this allows minimizing the time the process is in an unstable state.Applying the approach of A. Duncan, which he developed for Shewhart charts, a formula for the expectation of the duration of an unstable state of a process was obtained and a Python program was developed to minimize it. To test the set optimization problem, the calculation of the data of two process indicators is given and the optimal parameters of the generalized variance chart are obtained, at which the duration of the process in an unstable state is minimal.

PERFORMANCE EVALUATION OF COMPUTING SYSTEM AND NETWORK OBJECTS AT DIFFERENT LEVELS OF SURVIVABILITY

The article discusses an approach to calculating the performance of objects exposed to adverse effects (AE), based on Markov models of queuing theory operating in a random environment. Three types of models of service queuing systems with an unlimited and a limited queue are investigated differing from each other in the message processing modes performed in the recovery process after AE: (1) incoming messages continue to be executed with a different performance compared to the normal mode; (2) in the process of recovery, incoming messages are accumulated, and processing is blocked; (3) in the process of restoration, no messages are received and no processing of messages already in the queue is carried out. The modes of operation of objects change as a result of random influences of the external environment (cyberattacks, influences of the external environment or object failures). The models are considered under the simplest assumptions about the distributions of the input flows of messages arriving at the object, their service time, the distributions of the time of occurrence of the AE and the recovery time of the object after that (Poisson flows and exponential time of the considered time intervals). The developed models make it possible to evaluate the design decisions taken from the performance point of view on the organization of message service for a given survivability under stationary assumptions. Numerical examples illustrate the use of models for assessing performance indicators and some indicators of survivability of the objects under study.

AUTOMATION OF THE MAPLE SYSTEM CALCULATIONS FOR BUILDING THE DISCRETE MODELS OF THE MARINE-VESSEL COURSE AUTOPILOT

The article deals with a script created in the Maple language that allows to check the properties of complete controllability and observability of a mathematical model for a ship’s course autopilot as well as to compute the matrix parameters of a discrete model for its subsequent use when building an adaptive discrete Kalman filter in order to identify the uncertainty parameters of the model.