The possibilities of studying processes based on the geometric representation of their trajectories in a multidimensional space of factors and using projections of trajectories on planes suitable for analysis are discussed. A connection is established between such constructions and the spiral and snail of development. Based on the proposed projection, a development snail is defined as a special representation format of the purposeful process, expanding the possibilities of analysis of modelling results.
In today's world, the problem of information security is becoming critical. One of the most common cryptographic approaches is the elliptic curve cryptosystem. However, in elliptic curve arithmetic, the scalar point multiplication is the most expensive compared to the others. In this paper, we analyze the efficiency of the scalar multiplication on elliptic curves comparing Affine, Projective, Jacobian, Jacobi-Chudnovsky, and Modified Jacobian representations of an elliptic curve. For each coordinate system, we compare Fast exponentiation, Nonadjacent form (NAF), and Window methods. We show that the Window method is the best providing lower execution time on considered coordinate systems.
The article describes the full life cycle of an information system based on open Webtechnologies from the point of view of developers and system administrators. The article starts with the development of technical specifications for an information system creation and ends with the system’s launching into operation and its subsequent uninterrupted operation. As the example, the creation process of the information system for the Foundation of Algorithms and Programs of the Siberian Branch of the Russian Academy of Sciences is described.
A logic method for structural-parametric synthesis of a binary dynamical system with a given periodic trajectory is proposed. This method provides a constructive solution for the considered problem. The attraction region of such a trajectory must coincide with a given subset of the state space. An additional constraint sets the acceptable time for reaching this trajectory from its attraction region. As admissible structures for dynamical models of the synthesis, we consider the following systems: linear systems, systems with the disjunctive and conjunctive right sides. All conditions of the problem are written in the form of a quantified Boolean formula with subsequent verification of its truth using a specialized solver, which gives values of the required parameters of the dynamical model. The software implementation of the proposed method in the form of a composite service is presented. All stages of the parametric synthesis of a Boolean network based on the proposed method are demonstrated in the example of a one-step linear system.
The article develops an efficient implementation of an algorithm for detecting and correcting multivalued residual errors with a fixed number of calculations of the syndrome, regardless of the set of moduli size. Criteria for uniqueness are given that can be met by selecting moduli from a set of primes to satisfy the desired error correction capability. An extended version of the algorithm with an increase in the number of syndromes depending on the number of information moduli is proposed. It is proposed to remove the restriction imposed on the size of redundant moduli. Identifying the location of the error and finding the error vector requires only look-up tables and does not require arithmetic operations. In order to minimize the excess space, an extended algorithm is also proposed in which the number of syndromes and look-up tables increases with the number of information moduli, but the locations of errors can still be identified without requiring iterative computations. By using the approximate method, we have reduced the computational complexity of the algorithm for calculating the syndrome from quadratic to linear-logarithmic, depending on the number of bits in the dynamic range.
The problem of production planning as an element of Gartner enterprise architecture in a distributed organizational and technical system is considered on the example of a construction company of medium and large scale.Mathematical models for planning organizational and technical resources in a distributed system as elements of patterns are discussed.In the development of the information and application layers, field-proven solutions can be used as patterns.The approach to the organization of business processes of a construction company that allows solving the problem of optimal scheduling of construction works while simultaneously executing a number of projects by the company and, thus, increasing the management efficiency of a geographically distributed enterprise is considered.The enterprise architecture as a unified information environment for managers of a construction company, site managers, supply engineers, designers, and estimates is discussed.
The paper illustrates an application of the recently developed method of dealing with controlled automata-based discrete event systems with the help of logical inference. The method based on the calculus of positively constructed formulas is extended on the case of systems built out of sets of modules. Specifications restricting system behavior are also supposed to be modular. Due to the special features of the calculus of positively constructed formulas, it may be applied at the upper level of a robot group control system. The case study of mobile robots pushing a block to a target area is considered.
Software maintenance has been recognized as the most demanding and costly phase in the software life cycle. Software maintenance tasks, although require a more complex set of skills and knowledge, are far less interesting to software engineers than software development tasks. In addition, insight into the scholarly literature revealed that the knowledge basis on software maintenance is significantly less than the knowledge base on software development. Due to the obvious constraints of small software companies, they do not have time, people, and other resources for assessing and improving their software maintenance practice. This paper presents the author’s reflections on experience in assessing and improving software maintenance practice in an indigenous micro software company.
The article deals with the modelling of Artificial Neural Networks as an information transmission system to optimize their computational complexity. The analysis of existing theoretical approaches to optimizing the structure and training of neural networks is carried out. In the process of constructing the model, the well-known problem of isolating a deterministic signal on the background of noise and adapting it to solving the problem of assigning an input implementation to a certain cluster is considered. A layer of neurons is considered as an information transformer with a kernel for solving a certain class of problems: orthogonal transformation, matched filtering, and nonlinear transformation for recognizing the input implementation with a given accuracy. Based on the analysis of the proposed model, it is concluded that it is possible to reduce the number of neurons in the layers of neural network and to reduce the number of features for training the classifier.
The designing a digital twin of the process of the thermal cutting of sheet material using laser or gas equipment for its figure cutting is considered. The solution to the problem of optimizing the path of the cutting tool taking into account the thermal effects on the material to be cut is discussed. The solution of the problem of modeling the temperature change of the material to be cut is considered on the basis of a discrete - logical representation of information about the state of the technological system of sheet cutting. The results of a computational experiment are presented.
This paper is dedicated to the application of the multigrammatical framework to the assessment of vulnerability of energy infrastructures affected by impacts destroying (reducing capabilities of) their facilities (power plants, fuel producing plants, power transmission lines, fuel transporting pipes, as well as networking devices of both electricity and fuel subsystems of an energy infrastructures). A basic graph representation of energy infrastructures is considered, and technique of their multigrammatical representation is introduced. Criterial base for recognition of the energy infrastructures vulnerability, being a generalization of the similar criterial base developed regarding industrial infrastructures is proposed. Techniques of multigrammatical modelling reservation of energy infrastructures and their recovery after impacts is proposed. Directions of future research in this area are announced.
The property of observability of controlled binary dynamical systems is investigated. A formal definition of the property is given in the language of applied logic of predicates with bounded quantifiers of existence and universality. A Boolean model of the property is built in the form of a quantified Boolean formula accordingly to the Boolean constraints method developed by the authors. This formula satisfies both the logical specification of the property and the equations of the binary system dynamics. Aspects of the proposed approach implementation for the study of the observability property are considered. The technology of checking the feasibility of the property using an applied microservice package is demonstrated in several examples.
The complexity of creating artificial intelligence applications remains high. One of the factors that cause such complexity is the high qualification requirements for developers in the field of programming. Development complexity can be reduced by using methods and tools based on a paradigm known as End-user development. One of the problems that requires the application of the methods of this paradigm is the development of intelligent systems for supporting the search and troubleshooting onboard aircraft. Some tasks connected with this problem are identified, including the task of dynamic formation of task cards for troubleshooting in terms of forming a list of operations. This paper presents a solution to this problem based on some principles of End-user development: model-driven development, visual programming, and wizard form-filling. In particular, an extension of the Prototyping expert systems based on transformations technology, which implements the End-user development, is proposed in the context of the problem to be solved for Sukhoi Superjet aircraft. The main contribution of the work is as follows: expanded the main technology method by supporting event trees formalism (as a popular expert method for formalizing scenarios for the development of problem situations and their localization); created a domain-specific tool (namely, Extended event tree editor) for building standard and extended event trees, including for diagnostic tasks; developed a module for supporting transformations of XML-like event tree representation format for the knowledge base prototyping system – Personal knowledge base designer. A description of the proposed extension and the means of its implementation, as well as an illustrative example, are provided.
The article summarizes the accumulated practical experience of the authors in the development of algorithms for the formation of investment strategies. For this purpose, the optimization of the studied parameters, information support of investment activities, verification, monitoring and adjustment in the testing mode and the subsequent practical application of the described tools are considered. The system is based on the main provisions of the Markowitz portfolio theory. The analytical block of the Information System Portfolio Investor includes Profitability-Risk model; empirical models of optimal complexity; hybrid predictive model systems; the principle of combining (integrating) both models and forecasts, as well as decision rules; optimization of the training sample length (modified Markowitz model); optimization of the frequency of monitoring and adjusting the composition of the investment portfolio. The principles of design and development of the information block of the system, its replenishment and functioning are described in detail. All the above listed components of the algorithmic content of the investment decision making system are described sequentially. The system modules have been successfully tested on a wide class of financial instruments: ordinary shares, preferred shares, government and corporate bonds, exchange commodities, stock, commodity, industry and bond indices, exchange-traded investment funds and real estate funds. The implemented Markowitz model with a dynamic database of historical data can significantly increase the efficiency of investment decisions, which is facilitated by taking into account the characteristics of both the markets under study and the corresponding financial instruments.
In this article, the formulation and proof of the theorem on the difference in the ranks of the numbers represented in the Residue Number System is carried out. A method is proposed that allows to reduce the amount of necessary calculations and increases the speed of calculating the rank of a number relative to the method for calculating the rank of a number based on the approximate method. To find the rank of a number in the method for calculating the rank of a number based on the approximate method, it is necessary to calculate n operations with numbers exceeding the modulus value; in the proposed method, it is necessary to calculate n·(n−1)/2 operations not exceeding the value of the module.
The article considers the problem of decision support in the information maintenance of individual education trajectory. The development of algorithms and software for processes automating in educational systems requires a special approach. The use of ontological models makes it possible to unify the description of the elements of educational systems and apply the technology of digital footprints when managing business processes in educational systems. An ontological model for managing educational trajectories is proposed. An algorithm has also been developed to compare competence-based models of curricula using latent-semantic analysis. The proposed models and methods are implemented as a distributed software system using the semantic web approach on the basis of distributed RDF-storage. The effectiveness of the developed algorithms and software solutions is demonstrated by the example of academic mobility in Ufa State Aviation Technical University. Prospects for further research in this area are outlined.
Considering the growing appliance of wireless technologies in the Internet of Things and Wireless Sensor Networks the question of their coexistence and interoperability becomes extremely important. Wi-Fi and ZigBee technologies already have a long-lasting presence in the market as well as deployment in many systems. Because of their numerous appliances, it is extremely important to measure the impact of one technology on another. This paper has presented the approach of using open-source hardware and software for measuring the interference effects of Wi-Fi to ZigBee. The testing platform is built on Arduino microcontroller boards. This paper describes the experiment, the experimental platform, methodology, and tools used for collecting and analyzing data, as well as the experience gained during the experiments, and its influence on future work. The results presented in this paper give a clear insight into how the IEEE 802.11 networks influence the throughput of IEEE 802.15.4 networks when operating in similar frequencies. According to presented test results, Wi-Fi at distances of about 12m can affect the ZigBee throughput when the central frequency difference is 7 MHz or lower.
Article is dedicated to the multigrammatical modelling of games. Basic notions and definitions, concerning multisets and multiset grammars, are considered. So called resource-based games are introduced, and representation of their simplest class – antagonistic resource-based games – by filtering multiset grammars is considered in details. More sophisticated cooperative and coalitional resource-based games are proposed. Directions of further development of resource-based games by application of multigrammatical framework are discussed.
The study is devoted to one of the tasks related to information and computer systems with a different discipline of establishing connections between its nodes. Cases of systems with and without queues are considered. The efficiency of the systems (the relative load, the number of busy nodes, etc.) is calculated. To calculate the probability of the communication system being in one of the possible enlarged states, the corresponding Markov process is introduced and its asymptotic characteristics are determined.
The paper considers the problem of searching for the source of a non-stationary physical eld. We assume that the use of swarm algorithms may be applicable in this case. A hybrid of the Whale Optimization Algorithm and Grey Wolf Optimizer is proposed in this paper. The algorithm has several advantages over its origins: a more precise solution of the optimization problem for low-dimensional functions and a higher convergence rate of the first iterations. Two modications were made to adapt the algorithm to the requirements of the problem. The proposed algorithm is used as a basis for a control strategy for a group of autonomous underwater vehicles. As a result, in the vast number of cases, the group can find the source within the given number of search iterations.
