Harvester open publications of NAS Ukraine
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The problem of automating the planning of forces, means and resources for management of counteraction of emergency situations
No full textThe article deals with the issue of automating the planning of forces, means and resources used in the process of countering an emergency situation. A formal description of the task of planning forces, means and resources is provided, and it is justified that this task includes two interrelated tasks, which involve the assessment of the potential capabilities of the analyzed region in terms of the available forces, means and resources for countering an emergency situation and the generation of options for groupings of forces , means and resources functionally sufficient to counteract the analyzed emergency situation, taking into account the set of restrictions. The issue of automating the solution of the problems of assessing the potential opportunities of the region and generating variants of groupings of forces, means and resources is considered in detail. The main functions of the ANALYSIS and SYNTHESIS systems, by means of which these tasks are solved, are characterized. It is substantiated that thanks to the solution of these problems, the adaptation of the electronic action plan to the real possibilities of the region is ensured.Prombles in programming 2023; 3: 58-65
Study of the efficiency of some deterministic preprocessing methods for sorting algorithms
No full textTo verify the hypothesis about decrease in time of sorting by algorithms of different computational complexity experiments have been conducted. Several ideas on deterministic preprocessing of data arrays for sorting algorithms have been tested. The following algorithms are proposed: quick preprocessing – prediction of the index of an element in a sorted array and permutation, preprocessing with memory - prediction and permutation with memorization of previously set elements, preprocessing with reordering – reverting sequences of elements sorted in reverse order. Also proposed block variations of quick and preprocessing with memory, which are performed for parts of the array of a given length. It has been defined that the higher efficiency of preprocessing is achieved by using with sorting algorithms, which are significantly accelerated on sorted (or almost sorted) arrays of data. Block preprocessing methods can be performed faster due to the possibility of avoiding cache misses, but show a lower percentage of array sorting. Experiments were conducted to evaluate the effectiveness of various sorting algorithms after and together with the proposed preprocessing methods.Prombles in programming 2023; 4: 3-1
Information resources distribution between automated workstations in local corporative networks
Get PDFThis article focuses on the problem of optimal distribution of related information resources between automated workstations in local corporate networks. In this work we present a mathematical description of the algorithm for quasi-optimal distribution of related information resources at designing automated workstations in a local corporate network. The undirected graph describing the task of information resources optimal distribution is presented. The method of quasi-optimal distribution of related resources at designing automated workstations in the local corporative network is proposed based on the developed algorithm. Using conditional organization as an example the modeling of optimal distribution of related information resources has been considered in local corporative network. The described algorithm provides an opportunity to optimally distribute the information resource in the local corporate network, as well as solve the task of building reliable and efficient local networks. The proposed method of quasi-optimal distribution of related information resources can be used in corporation of any type.Problems in programming 2022; 2: 23-3
Bicomponent sorting algorithms
No full textThe possibilities of improving sorting time parameters through preprocessing by stochastic sorting were investigated. The hypothesis that two-component stochastic + classical sorting outperforms classic one-component sorting in terms of time efficiency was experimentally confirmed. Sorting with different computational complexity is accepted as classical sorting algorithms: shaker sort- ing with computational complexity O(n2), insertions O(n2), Shell O(n·(log n)2) ... O(n3/2), fast with optimization of ending sequences O(n·log n). The greatest effect is obtained when performing comparisons using stochastic sorting in the amount of 160 percent of the array’s size. Indicators of the efficiency of the exchange of two elements, as well as series of exchanges, are introduced. This allowed to determine the highest efficiency of stochastic sorting (as the first component of two-component sorting), when one element for comparison is chosen from the first part of the array and the other from the second. For algorithms with a computational complexity of O(n2) the improvement in time efficiency reached 70–80 percent. However, for Shell sort and quick sort, the stochas- tic presort has no positive effect, but instead increases the total sorting time, which is apparently due to the initial high efficiency of these sorting methods. The hypothesis that three-component sorting fast + stochastic + insertions would increase sorting time efficiency was not confirmed. However, during the experiment, the recommended size of the array was determined, at which point the two-component quick + insertion sort must be switched to the second component – insertion sorting. The optimal length of the ending sequences is between 60 and 80 elements. Given that algorithm time efficiency is affected by computer architecture, operat- ing system, software development and execution environment, data types, data sizes, and their values, time efficiency indicators should be specified in each specific case.Problems in programming 2022; 3-4: 32-4
Features of building recommendation systems based on neural network technology using multithreading
Get PDFThe article is devoted to the creation of a recommendation system for tourists regarding hotels using a neural network based on a multi- layer perceptron. The work uses the mechanism of parallelization of the training sample of the neural network. To check the quality of the provided recommendations, the average absolute and root mean square errors, accuracy and completeness were used. The results of the experiments showed that when analyzing 10 html pages with descriptions of hotels, the metrics of root mean square error and accuracy gave the best results at 500,000 epochs of neural network training when using 8 processors.Prombles in programming 2022; 3-4: 289-30
Development of decision support system using OLAP-technologies for information security monitoring systems
Get PDFThe article highlighted the need for continuous monitoring of the computer networks (CN) for information security and analyzed the sources of data for information security monitoring (ISM). Methods of data collection from various sources have been investigated, and categories of ISM systems have been studied. The architectural-technological model of the system supporting decision-making based on OLAP (Online Analytical Processing) and data warehouse has been proposed for quick response to security-related incidents and detected incidents in ISM systems.Prombles in programming 2022; 3-4: 403-40
Protecting public clients using an authorization algorithm
No full textThe paper focuses on authorization in public clients and provides a secure authorization model as an alternative to costly Microsoft Duende BFF solution. After providing a brief overview of confidential and public clients in terms of authorization, we have analyzed problems and potential attack vectors associated with the authorization process in public clients due to their inability to hold credentials securely. Confidential clients are implemented on secure servers or able to facilitate secure authentication by other means, while public clients lack this security. Our research discovered algorithms, models, and methods for secure authorization in public clients. As a part of our model, we have implemented high entropy Proof Key for Code Exchange generator in C# .NET 6.0. In addition, we have provided a solution to a problem of storing sensitive information in public clients using the Backend for Frontend concept. This concept leverages a reverse proxy pattern where a backend application acts as a proxy and handles all client requests. Having a proxy backend application significantly tightens security model for public clients, while restricting possible attack vectors. The authorization model being researched was based on Proof Key for Code Exchange and Backend for Frontend approach. During the testing phase of our research, we have confirmed that the model was not vulnerable to Cross-Site-Scripting and Auth Code Interception attacks. A sequence diagram outlining main actors and interactions among them in context of authorization has been designed. The diagram stands as the visual representation of the model that uses proposed methods and algorithms. As a result, we have managed to build an alternative to secure authorization solutions for public clients that do not rely on the client secret. We have summarized our key findings in a Blazor Web Assembly application, which is classified as public and uses the described authentication model.Prombles in programming 2022; 3-4: 409-416
Simulation of optimal pursuit strategies with simple motion
No full textStrategies for pursuit of a target by one pursuer with simple movement are considered. The criterion is the time to capture the target. The proof of the optimality of the parallel approach strategy and the chas- ing strategy is presented. The strategy of parallel approach consists in the fact that the pursuer, knowing the velocity vector of the target at current moment, considers this vector to be constant and calculates a point on the target’s line of motion at which capture can occur if the pursuer moves at a constant maxi- mum speed. At each instant of time, the pursuer’s velocity vector is directed to the capture point, and the magnitude of the velocity is maximal. If the pursuer moves at maximum speed in the direction of the target, the pursuit strategy is called a chasing strategy. A number of examples of pursuit using the strate- gies of parallel approach and chasing strategy, calculated by the numerical method, are given. The main parameters of the movement of the agents affecting the time of capture are determined: the speed of the target and the pursuer, the coordinates of the target and the pursuer at the time of the beginning of the pursuit, the type and parameters of the target’s movement line; the pursuit task is determined by these para-meters. On the basis of numerical modeling, a sets of problems is outlined for which the parallel approach strategy is better then the chasing strategy or vice versa. The selected movement parameters roughly correspond to the movement parameters of modern combat aircraft and air defense equipment; in numerical experiments, the absolute value of the acceleration of the target does not exceed 10g, where g is the accele-ration of free fall. Since the pursuer’s motion is considered simple, any absolute value of its acceleration is allowed. In the case of applying the parallel approach strategy, this value slightly differs from the absolute value of the target’s acceleration; if a chasing strategy is used, the absolute magnitude of the pursuer’s acceleration can be much larger.Prombles in programming 2022; 3-4: 478-48
Cloud service for authentication of a person based on their electrocardiogram
Get PDFTelemedicine grows faster with each year. In scope of it new technologies have been created to solve information communication problems. One of them is distance monitoring which requires electrocardiogram analysis. In this case it is important to confirm that the transferred electrocardiogram through information channels belongs to the patient. Researchers from different countries work on this problem. They suggest different methods of authentication by electrocardiogram. The goal of this work is to suggest a prototype of a service that could be used to authenticate electrocardiograms.The paper describes which algorithms have been used to build authentication technology and how it was implemented. There is a short history of built applications. It shows their structures and the purpose. The recently developed system is a prototype to authentication service. It performs registration of new electrocardiograms which is the most time consuming process in authentication. The paper describes the architecture of the system and shows the result of executed experiments. The results show that there is a performance issue with the machine learning library ML.NET. When a lot of cores are allocated to one machine learning instance the overheads highly decrease the overall experiment time. These experiments confirmed Amdahl’s law. Nevertheless, an architecture was found where experiments took the least time for execution. Knowing the issue with the machine learning library, a new architecture setup was suggested and will be implemented in future works.Besides, attention is paid on how developed service should help researchers to improve the technology. The main idea of the system is using one service for developing and testing the technology. That means we can be sure that the cloud service that runs on production would behave the same as in the research phase.Prombles in programming 2022; 3-4: 485-49
Organizational basics of operating digital platforms
No full textNetwork effects are determined by the influence of an additional user of a product or service on the value that other users attach to this product or service. Platforms are then defined as entities that connect economic agents, actively managing network effects among the digital copies (images) of those agents. Network effects are distinguished by their sources: such sources can be users of the only group or users of several groups. Because, on a digital platform, network effects are generated jointly by all users, regardless of the groups to which they belong, and interest in the platform increases when the volume of interaction this platform manages increases, it is difficult to distinguish between different sources of network effects. User participation in the platform and their application of platform features can be important because their active evaluation of products and services, together with information provided by user actions (for platforms that collect and apply big data), gives an understanding of those actions, allows providing better services by the platform or adding specific offers. When consumers search for a product, they face travel costs, price information costs, and product feature comparison costs. When suppliers are looking for a willing buyer, they incur travel costs and communication costs regarding their products. Intermediaries reduce transaction costs by centralizing the exchange. In the presence of a random-matching market, there are profitable opportunities for intermediaries to conduct centralized exchanges, since buyers and sellers are influenced by the type of their matching partner, and intermediation allows self-selecting for types of economic agents. Intermediated trade can partially or completely replace decentralized trade and lead to more socially efficient allocations.Prombles in programming 2022; 3-4: 491-501