卷 22, 编号 6 (2023)
Artificial intelligence, knowledge and data engineering
Real-Time Reliability Monitoring on Edge Computing: a Systematic Mapping
摘要
Scenario: System reliability monitoring focuses on determining the level at which the system works as expected (under certain conditions and over time) based on requirements. The edge computing environment is heterogeneous and distributed. It may lack central control due to the scope, number, and volume of stakeholders. Objective: To identify and characterize the Real-time System Reliability Monitoring strategies that have considered Artificial Intelligence models for supporting decision-making processes. Methodology: An analysis based on the Systematic Mapping Study was performed on December 14, 2022. The IEEE and Scopus databases were considered in the exploration. Results: 50 articles addressing the subject between 2013 and 2022 with growing interest. The core use of this technology is related to networking and health areas, articulating Body sensor networks or data policies management (collecting, routing, transmission, and workload management) with edge computing. Conclusions: Real-time Reliability Monitoring in edge computing is ongoing and still nascent. It lacks standards but has taken importance and interest in the last two years. Most articles focused on Push-based data collection methods for supporting centralized decision-making strategies. Additionally, to networking and health, it concentrated and deployed on industrial and environmental monitoring. However, there are multiple opportunities and paths to walk to improve it. E.g., data interoperability, federated and collaborative decision-making models, formalization of the experimental design for measurement process, data sovereignty, organizational memory to capitalize previous knowledge (and experiences), calibration and recalibration strategies for data sources.
Informatics and Automation. 2023;22(6):1243-1295
1243-1295
A Balanced Intrusion Detection System for Wireless Sensor Networks in a Big Data Environment Using CNN-SVM Model
摘要
Wireless Sensor Networks (WSNs) were exposed to several distinct safety issues and attacks regarding gathering and sending data. In this scenario, one of the most prevalent WSN assaults that may target any tier of the protocol stack is the Denial of Service (DoS) attack. The current research suggested various strategies to find the attack in the network. However, it has classification challenges. An effective ensemble deep learning-based intrusion detection system to identify the assault in the WSN network was, therefore, suggested in this research to address this issue. The data pre-processing involves converting qualitative data into numeric data using the One-Hot Encoding technique. Following that, Normalization Process was carried out. Then Manta-Ray Foraging Optimization is suggested to choose the best subset of features. Then Synthetic Minority Oversampling Technique (SMOTE) oversampling creates a new minority sample to balance the processed dataset. Finally, CNN–SVM classifier is proposed to classify the attack kinds. The Accuracy, F-Measure, Precision, and Recall metrics were used to assess the outcomes of 99.75%, 99.21%, 100%, and 99.6%, respectively. Compared to existing approaches, the proposed method has shown to be extremely effective in detecting DoS attacks in WSNs.
Informatics and Automation. 2023;22(6):1296-1322
1296-1322
Algorithm of Constituency Tree from Dependency Tree Construction for a Russian-Language Sentence
摘要
Automatic syntactic analysis of a sentence is an important computational linguistics task. At present, there are no syntactic structure parsers for Russian that are publicly available and suitable for practical applications. Ground-up creation of such parsers requires building of a treebank annotated according to a given formal grammar, which is quite a cumbersome task. However, since there are several syntactic dependency parsers for Russian, it seems reasonable to employ dependency parsing results for syntactic structure analysis. The article introduces an algorithm that allows to construct the constituency tree of a Russian sentence by a syntactic dependency tree. The formal grammar used by the algorithm is based on the D.E. Rosenthal’s classic reference. The algorithm was evaluated on 300 Russian-language sentences. 200 of them were selected from the aforementioned reference, and 100 from OpenCorpora, an open corpus of sentences extracted from Russian news and periodicals. During the evaluation, the sentences were passed to syntactic dependency parsers from Stanza, SpaCy, and Natasha packages, then the resulted dependency trees were processed by the proposed algorithm. The obtained constituency trees were compared with the trees manually annotated by experts in linguistics. The best performance was achieved using the Stanza parser: the constituency parsing F1–score was 0.85, and the sentence parts tagging accuracy was 0.93, that would be sufficient for many practical applications, such as event extraction, information retrieval and sentiment analysis.
Informatics and Automation. 2023;22(6):1323-1353
1323-1353
Robotics, automation and control systems
Motion Primitives in the Trajectory Planning Problem with Kinematic Constraints
摘要
Automatic trajectory planning is an urgent scientific and technical problem, whose solutions are in demand in many fields: unmanned transportation, robotic logistics, social robotics, etc. Often, when planning a trajectory, it is necessary to consider the fact that the agent (robot, unmanned car, etc.) cannot arbitrarily change its orientation while moving, in other words, it is necessary to consider kinematic constraints when planning. One widespread approach to solving this problem is the approach that relies on the construction of a trajectory from prepared parts, motion primitives, each of which satisfies kinematic constraints. Often, the emphasis in the development of methods implementing this approach is on reducing the combinations of choices in planning (heuristic search), with the set of available primitives itself being regarded as externally defined. In this paper, on the contrary, we aim to investigate and analyze the effect of different available motion primitives on the quality of solving the planning problem with a fixed search algorithm. Specifically, we consider 3 different sets of motion primitives for a wheeled robot with differential drive. As a search algorithm, the A* algorithm well known in artificial intelligence and robotics is used. The solution quality is evaluated by 6 metrics, including planning time, length and curvature of the resulting trajectory. Based on the study, conclusions are made about the factors that have the strongest influence on the planning result, and recommendations are given on the construction of motion primitives, the use of which allows to achieve a balance between the speed of the planning algorithm and the quality of the trajectories found.
Informatics and Automation. 2023;22(6):1354-1386
1354-1386
Application of Harmonic Half-Waves for Automation of High-Speed Trains Control
摘要
The emergency braking processes in the European Train Control System (ETCS) of high-speed trains are associated with stepwise regulation of acceleration (deceleration) depending on the braking ability of the train, terrain data and changing weather on the route. These processes are defined in ETCS. The procedure for stepwise regulation of deceleration is carried out by the driver repeatedly in the process of braking until the train stops completely. The beginning of emergency braking and its end, as well as the braking process itself, is accompanied by repeated pulsed operation of the brakes, which leads to jumps in deceleration and, accordingly, to increased wear of the brake system, a decrease in comfort for passengers, which results in the limitation of the maximum allowable speed. The article proposes a new concept and technique for constructing mathematical models of emergency braking curves different from ETCS curves and based on harmonic half-waves. It is shown that the ETCS deceleration curves are described by known second-order power half-waves. Their joint study gives grounds to assert that the application of these curves leads to the obligatory pulsed mode of brake operation. Two new variants of models of emergency braking curves described by harmonic half-waves are proposed. The first option has one pulsed brake application at the end of the braking interval. The second option is free from braking impulses and allows the use of continuous regulation. These models explain the features of ETCS, contain proposals for their elimination, and are applicable to the development of new emergency braking curves that allow smooth control of emergency braking of trains. Efficiency, differences and advantages over ETCS braking curves are shown on the results of mathematical modeling of emergency braking processes.
Informatics and Automation. 2023;22(6):1387-1414
1387-1414
Mathematical modeling and applied mathematics
Mathematical Modeling of the Processes of Executing Packages of Tasks in Conveyor Systems with Intermediate Buffers of Limited Size
摘要
Modern methods of process planning in conveyor systems with buffers of a certain size between processing devices allow optimizing schedules for single tasks or fixed task packages with a limited number of them and a limited number of devices. The use of mathematical models of the processes of performing single tasks (task packages) used by these methods in optimizing the composition of packages and schedules for their execution in systems with an arbitrary number of packages and devices is impossible. At the same time, mathematical models of the processes of executing task packages in conveyor systems in the presence of buffers of limited sizes between devices are the basis for the development of methods for optimizing their (package) compositions and schedules for the implementation of actions with them on the devices of conveyor systems. In this regard, the article develops mathematical models of multi-stage processes of performing an arbitrary number of task packages in conveyor systems in the presence of intermediate buffers of limited sizes for two and three devices, as well as for an arbitrary number of devices. The use of these models makes it possible to determine the time points of the start of the execution of task packages on the devices of conveyor systems, taking into account the limited size of intermediate buffers, as well as the duration of time intervals for the use of these resources and the efficiency of their use over time. An algorithm has also been developed for mathematical modeling of the processes of executing task packages in conveyor systems in the presence of intermediate buffers of limited size, which calculates the time characteristics of these processes based on a given order of implementation of actions with task packages on the devices of conveyor systems. An application has been developed that implements synthesized mathematical models of the processes of executing task packages in conveyor systems with intermediate buffers of limited sizes and an appropriate method for modeling these processes. Versatile testing of the developed application has shown that the obtained mathematical models and the modeling method adequately describe the course of multi-stage processes of task packages in pipeline systems, set using different values of their (processes) parameters.
Informatics and Automation. 2023;22(6):1415-1450
1415-1450
On the Partial Stability of Nonlinear Discrete-Time Systems with Delay
摘要
A system of nonlinear discrete (finite-difference) of a general form with a bounded delay is considered. Interest in the tasks of qualitative analysis of such systems has increased significantly in recent years. At the same time, the problem of stability with respect to all variables of the zero equilibrium position, which has a great generality, is mainly analyzed in domestic and foreign literature. The main research method is a discrete-functional analogue of the direct Lyapunov method. In this article, it is assumed that the system under consideration admits a “partial” (in some part of the state variables) zero equilibrium position. The problem of stability of a given equilibrium position is posed, and stability is considered not in all, but only in relation to a part of the variables that determine this equilibrium position. Such a problem belongs to the class of problems of partial stability, which are actively studied for systems of various forms of mathematical description. The proposed statement of the problem complements the scope of the indicated studies in relation to the system under consideration. To solve this problem, a discrete version of the Lyapunov– Krasovskii functionals method is used in the space of discrete functions with appropriate specification of the functional requirements. To expand the capabilities of this method, it is proposed to use two types of additional auxiliary (vector, generally speaking) discrete functions in order to: 1) adjustments of the phase space region of the system in which the Lyapunov–Krasovskii functional is constructed; 2) finding the necessary estimates of the functionals and their differences (increment) due to the system under consideration, on the basis of which conclusions about partial stability are made. The expediency of this approach lies in the fact that as a result, the Lyapunov-Krasovskii functional, as well as its difference due to the system under consideration, can be alternating in the domain that is usually considered when analyzing partial stability. Sufficient conditions of partial stability, partial uniform stability, and partial uniform asymptotic stability of the specified type are obtained. The features of the proposed approach are shown on the example of two classes of nonlinear systems of a given structure, for which partial stability is analyzed in parameter space. Attention is drawn to the expediency of using a one-parameter family of functionals.
Informatics and Automation. 2023;22(6):1451-1472
1451-1472
Vegetation Indices (NDVI and EVI) Time Series Approximation for Monitoring Crops of Khabarovsk Territory
摘要
Approximation of the series of the seasonal vegetation index time series is the basis for monitoring agricultural crops, their identification and cropland classification. For cropland of the Khabarovsk Territory in the period from May to October 2021, NDVI and EVI time series were constructed using Sentinel-2A (20 m) multispectral images using a cloud mask. Five functions were used to approximate time series: Gaussian function; double Gaussian; double sine wave; Fourier series; double logistic. Characteristics of extremums for approximated time series for different types of arable land were built and calculated: buckwheat, perennial grasses, soybeans, fallow and ley. It was shown that each type requires a characteristic species. It was found (p<0.05) that Fourier approximation showed the highest accuracy for NDVI and EVI series (average error, respectively, 8.5% and 16.0%). Approximation of the NDVI series using a double sine, double Gaussian and double logistic function resulted in an error increase of 8.9-10.6%. Approximation of EVI series based on double Gaussian and double sine wave causes an increase in average errors up to 18.3-18.5%. The conducted a posteriori analysis using the Tukey criterion showed that for soybean, fallow and ley lands, it is better to use the Fourier series, double Gaussian or double sine wave to approximate vegetation indices, for buckwheat it is advisable to use the Fourier series or double Gaussian. In general, the average approximation error of the NDVI seasonal time series is 1.5-4 times less than the approximation error of the EVI series.
Informatics and Automation. 2023;22(6):1473-1498
1473-1498
Forecasting in Stock Markets Using the Formalism of Statistical Mechanics
摘要
The possibility and expediency of forecasting in the stock markets are analyzed analytically using the methods and approaches of statistical mechanics. The apparatus of statistical mechanics is used to analyze and forecast one of the most important indicators of the market – the distribution of its logarithmic profitability. The Lotka-Volterra model used in ecology to describe systems of the "predator-prey" type was used as the initial model. It approximates market dynamics adequately. In the article, its Hamiltonian property is used, which makes it possible to apply the apparatus of statistical mechanics. The apparatus of statistical mechanics (using the principle of maximum entropy) makes it possible to implement a probabilistic approach that is adapted to the conditions of stock market uncertainty. The canonical variables of the Hamiltonian are presented as logarithms of stock and bond prices, the joint probability distribution function of stock and bond prices is obtained as a Gibbs distribution. The Boltzmann factor, included in the Gibbs distribution, allows us to estimate the probability of the occurrence of certain stock and bond prices and obtain an analytical expression for calculating the logarithmic return, which gives more accurate results than the widely used normal (Gaussian) distribution. According to its characteristics, the resulting distribution resembles the Laplace distribution. The main characteristics of the resulting distribution are calculated – the mean value, variance, asymmetry, and kurtosis. Mathematical results are presented graphically. An explanation is given of the cause-and-effect mechanism that causes a change in the profitability of the market. For this, the idea of Theodore Modis about the competition between stocks and bonds for the attention and money of investors is developed (by analogy with the turnover of biomass in models of the "predator-prey" type in biology). The results of the study are of interest to investors, theorists, and practitioners of the stock market. They allow us to make thoughtful and balanced investment decisions due to a more realistic idea of the expected return and a more adequate assessment of investment risk.
Informatics and Automation. 2023;22(6):1499-1541
1499-1541