Operation Of Complex Systems Research Articles

Direct ink writing of viscous inks in variable gravity regimes using parabolic flights

Additive manufacturing (AM) has significant utility for off-planet fabrication where dedicated infrastructure is severely limited, weight reduction and in situ resource utilization is desirable, and demands for complex systems are high. Direct ink writing (DIW) is a useful AM technique since it enables the deposition of a broad set of materials and the co-printing of multiple materials simultaneously. This allows for the fabrication of complex functional devices and systems in addition to structural objects. To evaluate this technique for space applications, this study characterized DIW in low gravity environments. Parabolic flights were used to simulate Martian, Lunar, and Micro gravity, and the effects that these 3 gravity regimes have on two critical print performance parameters, drooping and slumping, was evaluated using viscous paste inks deposited with an auger-driven extrusion head. In the drooping case, bridging structures were printed across gaps without support material, and the deformation was monitored. In the slumping case, a wall was printed through sequential layer deposition, and the vertical displacement of each layer under reduced gravity was explored. As expected, we found that a reduction in apparent gravity led to a decrease in the droop of a printed line, and as apparent gravitational acceleration is decreased its impact on the magnitude of drooping becomes less significant. For wall structures printed in simulated Lunar or Martian gravity regimes, the total structure height was found to be similar to that of a structure printed under Earth's gravitational conditions. In contrast, for prints performed in microgravity, it was found that slumping was significantly reduced and structure height was larger. These results provide experimental data to enable the design and optimization of appropriate structures and tool paths for printing objects using DIW for off-planet manufacturing.

Visual performance as a factor of increase performance in ball shooting

The article examines the question of the effectiveness of the factor of visual performance on indicators of technical training of shooters of different levels. In particular, the indicator of the average length of the aiming trajectory during the performance of the competitive exercise AP-3 on the electronic simulator "Scatt" was studied. The purpose of the article: to justify the need to use indicators of visual performance when analyzing the technical characteristics of a shot, obtained on the basis of the use of the optoelectronic simulator "Scatt". The methodological basis of the study was a systematic approach, which allows considering the aiming phase as a complex functional system of constant sensory control over the shooter's precise movements. The research used the method of computer simulation of the execution of a shot based on the use of an electronic simulator. To study visual performance, the correction test method was used. To assess visual productivity, which characterizes working capacity, the Weston formula was used, which calculated the quality and speed of visual work, as well as its integral index. The scheme of the ascertainment experiment consisted in the parallel collection of data on indicators of technical readiness and visual performance when performing the competitive exercise AP-3 (AP-60 according to the international classification) on the " Scatt " simulator. Correction sheets were filled out before and after the mentioned competitive exercise. The scientific novelty consists in substantiating the significance of the factor of visual performance as a stable sensory ophthalmoergonomic basis of the predictor of the average length of the aiming trajectory.

Mechanisms of Understanding: Nikolay A. Rubakin’s Mnema Theory

The study provides a brief overview of the Mnema Theory, a bibliopsychological theory based on the achievements in physiology and evolutionary biology formulated by Russian bibliographer, book critic, popularizer of science and writer Nikolai Alexandrovich Rubakin (Nicholas Rubakin), and the one which allows consistently and vividly reveal the structure of the human psyche, and show the mechanisms associated with understanding in general and understanding words and text, in particular. The Theory of Mnema, although presented to the scientific community at the beginning of the 20th century, is nevertheless highly relevant after a hundred years, and there continues to be more and more evidence pointing to the veracity and credibility of its provisions from modern humanitarian and natural sciences. Nikolay A. Rubakin’s Theory of Mnema is formulated on the basis of three laws of bibliopsychology: Zemon’s Law, Humboldt-Potebnya’s Law and Teng’s Law, and shows the structure of the human psyche in the form of mnema, which is a system of records received from external stimuli. According to Nikolay A. Rubakin’s theory, the mnema are a complex open system that is in a state of permanent development, and is always being added to and is continually changing. The complex composition of the reader’s mnema determines the perception and interpretation of a text, which is also understood as the external stimulus that generates a set of engrams and their activation leading to their subsequent ecphorias, as well as the projections that a reader receives when understanding texts. The validity of Nikolay A. Rubakin’s Theory of Mnema is confirmed by psychophysiological experiments aimed at measuring the semantic proximity of words (experiments of A.R. Luria and O.S. Vinogradova), psychological and psycholinguistic experiments (for example, Rorschach tests and various kinds of associative experiments), as well as the achievements of the philological science itself with regard to the study of the space of artistic and non-artistic text, the actual images of the author and the characteristics of the interpretations of the text by readers and researchers.

Prolonged hysteresis in the Kuramoto model with inertia and higher-order interactions.

The inclusion of inertia in the Kuramoto model has long been reported to change the nature of a phase transition, providing a fertile ground to model the dynamical behaviors of interacting units. More recently, higher-order interactions have been realized as essential for the functioning of real-world complex systems ranging from the brain to disease spreading. Yet analytical insights to decipher the role of inertia with higher-order interactions remain challenging. Here, we study the Kuramoto model with inertia on simplicial complexes, merging two research domains. We develop an analytical framework in a mean-field setting using self-consistent equationsto describe the steady-state behavior, which reveals a prolonged hysteresis in the synchronization profile. Inertia and triadic interaction strength exhibit isolated influence on system dynamics by predominantly governing, respectively, the forward and backward transition points. This paper sets a paradigm to deepen our understanding of real-world complex systems such as power grids modeled as the Kuramoto model with inertia.

Stretched exponential to power-law: crossover of relaxation in a kinetically constrained model

The autocorrelation function in many complex systems shows a crossover in the form of its decay: from a stretched exponential relaxation (SER) at short times to a power law at long times. Studies of the mechanisms leading to such multiple relaxation patterns are rare. Additionally, the inherent complexity of these systems makes it hard to understand the underlying mechanism leading to the crossover. Here we develop a simple one-dimensional spin model, which we call a domain wall (DW) to doublon model, that shows such a crossover as the nature of the excitations governing the relaxation dynamics changes with temperature and time. The relevant excitations are DWs and bound pairs of DWs, which we term ‘doublons’. The diffusive motion of the DWs governs the relaxation at short times, whereas the diffusive motion of the doublons yields the long-time decay. This change of excitations and their relaxation leads to a crossover from SER to a power law in the decay pattern of the autocorrelation function. We augment our numerical results with simple physical arguments and analytic derivations.

Non-Invasive Hardware Trojans Modeling and Insertion: A Formal Verification Approach

In modern chip designs, shared resources are used extensively. Arbiters usage is crucial to settle conflicts when multiple requests compete for these shared resources. Making sure these arbiter circuits work correctly is vital not just for their proper functionality, but also for security reasons. The work in this paper introduces a method based on formal verification to thoroughly assess the proper functional aspects of various arbiter setups. This is achieved through SystemVerilog assertions and model checking. Additionally, we explore a non-invasive method for the modeling and insertion of different types of hardware Trojans. These Trojans, with their unique triggers and payloads, are modeled formally without the need for any alterations to the actual circuit. The results provide a detailed analysis of the cost involved in running the formal verification environment on versions of arbiters that are free from Trojans. This analysis is carried out using Questa PropCheck formal analysis tool, which offers valuable insights into the time and memory resources required. Furthermore, the results highlights how the formally modeled and inserted Trojans interfere with hold criteria of the arbiters’ properties, where at least a single property fires due to the inserted Trojan. This work can be extended to be a generic approach with the potential to validate both the proper operation and security aspects of complex systems.

Research on Inbound Jobs’ Scheduling in Four-Way-Shuttle-Based Storage System

The four-way-shuttle-based storage and retrieval system is a recent innovative intelligent vertical warehousing system that has been widely applied in manufacturing and e-commerce environments due to its high flexibility and density. As a complex multi-device cooperative operational system, this system features the parallel operation of multiple elevators and four-way shuttles. During large-scale-batch inbound operations, the quality of scheduling solutions for inbound-operation equipment significantly impacts the system’s efficiency and performance. In this paper, a detailed analysis of the inbound-operation process in the system is conducted, taking into consideration the motion characteristics of both the elevators and four-way shuttles. Furthermore, we establish operational time constraints that account for equipment acceleration and deceleration characteristics and introduce a flexible flow-shop-scheduling model to address the scheduling problem in the system. Additionally, we propose an improved genetic algorithm based on double-layer encoding to solve this problem. Comparative experiments with a traditional genetic algorithm and ant-colony algorithm demonstrate the superior efficiency and accuracy of our approach. Finally, the effectiveness of the proposed algorithm is validated through comparisons with large-scale practical experiments.

Optimal Management in the Operation of Complex Technical Systems

Developing a cost management system for a complex technical system (CTS) at the stages of its life cycle is a modern trend aimed at creating sustainable cooperation ties based on requirements, including those of manufacturers and consumers. The article explores the concept of a complex technical system. The principles and properties of a complex technical system were described. A model of a procedure for checking the operability of a complex technical system with an arbitrary distribution of the time of independent manifestation of a failure was proposed for the example of compressor station equipment. Models of operation of complex technical systems based on information about their state were considered. It was also shown how to optimize maintenance decisions for these systems in terms of the minimum average unit cost and how reliable this ensures. Additionally, proof of the existence of an optimal verification strategy was given. An algorithm for determining the moments of verification was developed to ensure the minimum cost. The methods of collecting, processing, and effectively using information for making decisions about the technical condition of complex products and the possibility of further exploitation were improved based on selecting informative diagnostic features and constructing models that comprehensively consider the maximum and current level of their parameters. This allowed for the quality of the final products to be ensured. The practical use of the proposed methods of diagnosis and forecasting made it possible to increase the actual CTS resource by 1.5–2.0 times. This also increased the productivity of the technological process by 1.6 times due to the reduction of the number of stops for maintenance for replacement, adjustments, and sub-adjustments. As a result, the value of the lack of basic production was reduced from 1.2 % to 0.8 %, and the cost of manufacturing products was decreased by 1.2–2.0 times.

Safety assessment of technical systems based on limit values

Ensuring the safe operation of complex technical systems is an urgent task. Complex technical systems include lifting, mobile, agricultural machinery, etc. Absolutely every complex system fails during operation. At the same time, failures can have different effects not only on reliability indicators, but also on the degree of safety. The degree of safety of operation of complex equipment is directly influenced by the probability and nature of the occurrence of failures. Thus, in order to increase operational safety, it is necessary to reduce the risk of a negative event, which is defined as the possibility of an adverse event occurring, that is, a combination of the degree of negative consequences with the possibility of its occurrence. The article provides an example of calculating the risk of failure; a method for calculating the parameters of the three-parameter Weibull distribution is proposed; an algorithm for determining three parameters of the Weibull law for a sample is given; the results of parameter calculations are presented; Proposals have been put forward for ways to increase the level of reliability and safety, respectively.

Feto-Maternal Interface Organ-on-Chip: A New Technology to Study Ascending Infection.

Modeling human pregnancy is challenging as two subjects, the mother and fetus, must be evaluated in tandem. To understand pregnancy, parturition, and adverse pregnancy outcomes, the two feto-maternal interfaces (FMi) that form during gestation (i.e., the placenta and fetal membrane) need to be investigated to understand their biological roles, and organ dysfunction can lead to adverse outcomes. Adverse pregnancy outcomes such as preterm rupture of the membranes, spontaneous preterm birth, preeclampsia, intra-uterine growth restriction, and gestational diabetes rates are on the rise worldwide, highlighting the need for future studies and a better understanding of molecular and cellular pathways that contribute to disease onset. Current in vivo animal models nor in vitro cell culture systems can answer these questions as they do not model the function or structure of human FMis. Utilizing microfabrication and soft-lithography techniques, microfluidic organ-on-chip (OOC) devices have been adapted by many fields to model the anatomy and biological function of complex organs and organ systems within small in vitro platforms.These techniques have been adapted to recreate the fetal membrane FMi (FMi-OOC) using immortalized cells and collagen derived from patient samples. The FMi-OOC is a four-cell culture chamber, concentric circle system, that contains both fetal (amniochorion) and maternal (decidua) cellular layers and has been validated to model physiological and pathological states of pregnancy (i.e., ascending infection, systemic oxidative stress, and maternal toxicant exposure). This platform is fully compatible with various analytical methods such as microscopy and biochemical analysis. This protocol will outline this device's fabrication, cell loading, and utility to model ascending infection-related adverse pregnancy outcomes.

A mathematical model of the process of functioning of an unattended complex technical system under conditions of high-power electromagnetic influence

Problem statement. The existing mathematical models of the functioning of maintenance-free complex technical systems (STS) have a narrow focus on the types of degrading effects, and do not allow a comprehensive assessment of the quality of the functioning of the NSTS under the influence of high-power electromagnetic radiation. The purpose of the work. To propose a mathematical model of the STS functioning process under conditions of high-power electromagnetic influence. Results. The author's view on the improvement of existing mathematical models of the NSTS functioning process under conditions of high-power electromagnetic influence is presented. A mathematical model of the functioning process has been developed. Practical significance. The developed mathematical model based on the generalization of experimental data on the resistance of semiconductor elements to EMV BM and models of analytical description of the mechanisms of action allows us to obtain computational and experimental dependences of the criterion levels of resistance of functional elements (FE) of NSTS on the parameters of EMV BM. What is new is the use in assessing the criteria levels of resistance, along with the duration and rate of front rise, the frequency of EMR repetition under repeated exposures, as well as taking into account third-party EMR of natural origin.

The Constrained Disorder Principle Defines Mitochondrial Variability and Provides A Platform for A Novel Mechanism for Improved Functionality of Complex Systems

The Constrained Disorder Principle Defines Mitochondrial Variability and Provides A Platform for A Novel Mechanism for Improved Functionality of Complex Systems

ЗАСТОСУВАННЯ СИСТЕМНОГО ПІДХОДУ ПРИ ВИКОНАННІ ІТ-ПРОЕКТІВ

Abstract. Modern requirements for the profession of an IT specialist are determined not only by the ability to work with specific technologies or programming languages. Today, an IT specialist faces a deeper task - understanding the functioning of complex systems and having the skills to analyze and solve complex problems. System analysis is a key success factor in the field of information technology, contributing to a holistic approach to solving problems and tasks that arise before IT specialists. Demand for systems analysts is growing rapidly and they are becoming an integral part of the IT team. Keywords: integrated software tools, IT team, competitiveness, principles of system analysis, system analyst.

Результативність функціонування підприємств як систем на засадах SEE-управління: сутність, урахування фактора часу та циклічності

The aim of the article is to outline approaches to managing the effectiveness of certain processes in terms of final consequences in the context of improving the efficiency of functioning of enterprises as complex systems. The approaches are defined on the basis of the author’s models and indicators of the components of effectiveness in them on the basis of SEE-management, taking into account the effect of the time factor and cyclicity. The results of the research indicated the importance of taking into account the effect of the time factor on the development of socioeconomic systems of different hierarchical levels. It is emphasized that consideration of varieties of cycles gives a broader and at the same time more accurate idea of the course of certain processes in the enterprise as in a system at the micro level. Methodological approaches to SEE-management of complex systems, which are based on the author’s indicators of the components of the effectiveness of the processes of functioning of complex systems of any types and hierarchical levels, are outlined. The effectiveness of the processes is proposed to be assessed through the implementation and interpretation of the results of the SEE-analysis, as well as appropriate recommendations are provided, taking into account the SEE-reserves and SEE-risks, which makes it possible to carry out SEE-forecasts of the development of systems. It is noted that SEE management requires appropriate SEE-actions in relation to the processes under study. It is proposed to consider F-impulses (factors) that contributed to and/or hindered the motivation of managerial decision-making in systems of the appropriate hierarchical type and level as indicators of the direction of the consequences of processes. In order to effectively manage the process, the concept of the so-called percentage gap in the effectiveness of such a process with the corresponding indicator has been introduced. The proposed approaches to SEE-management of complex systems diversify the options for finding their further development. Consideration of the issues presented in the article from an applied point of view in our future research will contribute to the improvement of instruments and methods of management, in particular SEE-management, at enterprises as systems at the micro level.

Оновлені підходи до ризик-менеджменту в контексті моделювання результативності функціонування підприємств на засадах SEE-управління

The aim of the article is to reveal the essence and outline the methodology of risk management as a means of increasing the efficiency of the process of functioning of enterprises as complex systems on the basis of the author’s models and indicators of the components of effectiveness on the basis of SEE-management. The results of studies of some aspects of risk management at industrial enterprises in the process of their functioning contributed to the clarification of the main issues regarding its essence on the basis of the effectiveness of certain processes in such functioning in the context of risk management, which is one of the key concepts of such management based on SEE-management using SEE-analysis. It is noted that risk management is the process of making decisions and taking measures aimed at changing risk. These measures can be the proposed SEE-actions in the process of SEE-management. The conception of risk management is considered on the basis of the use of the SEE-management methodology, which contributes not only to the identification of risks and assessment of their impact on the functioning of enterprises as systems, but also to the use of the instruments of this management (indicators of the components of the effectiveness of certain processes, the results of SEE-analysis with the search for SEE-risks and the development of measures to prevent them), both system and process approaches to risk management. It is proposed to consider the SEE-risk of the processes of functioning of complex systems as the probabilistic failure to obtain the desired compared to the expected levels of scale, efficiency, effectiveness, which leads to errors and/or errors in SEE-management. The implementation of the SEE-management methodology on the provided example of the process of formation of gross income of a real operating enterprise has shown that it can be applied in practice in order to make scientifically sound managerial decisions at the micro-level in the context of risk management, and, if necessary, at the meso- and macro-levels by appropriately linking certain processes with the help of a set of models of the components of effectiveness.

ЛЕКСИЧЕСКАЯ СИНОНИМИЯ В СИТУАЦИЯХ ЮРИДИЧЕСКОГО ДИСКУРСА С ПОЗИЦИЙ ЛИНГВИСТИЧЕСКОЙ СИНЕРГИИ

The article dwells on lexical synonyms in the situations of legal discourse. The research is based on the idea of selforganization of complex open systems. Legal discourse as an open nonlinear system, author’s intentions as an attractor in a separate communicative block, general and special factors stabilizing the system of discourse are considered. The author’s attention is mainly focused on semantic variants in the statement/text as one of the linguistic means used by the actor to achieve the goals in a specific communicative situation (indictment, prosecutor’s closing argument, outline). The conclusion is made about the functionality of semantic variants in the process of transferring the intention.

Designs and Applications for the Multimodal Flexible Hybrid Epidermal Electronic Systems.

Research on the flexible hybrid epidermal electronic system (FHEES) has attracted considerable attention due to its potential applications in human-machine interaction and healthcare. Through material and structural innovations, FHEES combines the advantages of traditional stiff electronic devices and flexible electronic technology, enabling it to be worn conformally on the skin while retaining complex system functionality. FHEESs use multimodal sensing to enhance the identification accuracy of the wearer's motion modes, intentions, or health status, thus realizing more comprehensive physiological signal acquisition. However, the heterogeneous integration of soft and stiff components makes balancing comfort and performance in designing and implementing multimodal FHEESs challenging. Herein, multimodal FHEESs are first introduced in 2 types based on their different system structure: all-in-one and assembled, reflecting totally different heterogeneous integration strategies. Characteristics and the key design issues (such as interconnect design, interface strategy, substrate selection, etc.) of the 2 multimodal FHEESs are emphasized. Besides, the applications and advantages of the 2 multimodal FHEESs in recent research have been presented, with a focus on the control and medical fields. Finally, the prospects and challenges of the multimodal FHEES are discussed.

CONTROL ALGORITHMS FOR MOTORS OF ANTHROPOMORPHIC GRIPPING WITH GROUP DRIVE

Problem statement: the current trend is the use in various spheres of human activity of service robots equipped with anthropomorphic grippers (AG) with the capabilities inherent in the human hand. The functionality of the AG is determined by the executive groups of links (IGZ) having a group drive with a variable structure. When enclosing an external object (VO), each opposed IGZ sequentially implements a contact with three output links. The algorithm for the simultaneous control of the motors must ensure that the position of the unsecured AO remains unchanged. Known AG control methods, for example impedance, do not provide this requirement. In addition, possible methods are focused on an unchanging control object, which is one output link of the IGZ. The variability of control objects, characteristic of systems with a group drive and a variable structure, determines the need for a fundamentally new approach to the control of engines of opposed IGZs. Methods used: theoretical research is based on the main provisions of the analysis of the functioning of complex systems, information processing that determines their state and decision-making based on them. The novelty of the proposed algorithms lies in the fact that the engine control is based on information about the interaction of the output links of both this IGZ and the opposite one. The sequence of switching on the motors is determined based on the analysis of changes in the set of conditions. External - the contact of the current control object with the VO, internal - an increase in the torque on the engine in comparison with the value that determines the free movement. This approach makes it possible, with only contact sensors on the output links, to implement adaptive control of the motors of the opposed IGZ. Result: The use of the proposed algorithms makes it possible to formalize the control of the motors of the opposed IGZ taking into account the position of the initially non-deterministic AO. Practical significance: the developed algorithms are designed to control anthropomorphic grips performing actions with the AO in unfavorable conditions for humans and the uncertainty of the AO position. Their use will increase the functionality of robots equipped with AG.

MANAGEMENT OF ECONOMIC SECURITY OF ENTERPRISES IN THE CONTEXT OF DIGITAL TRANSFORMATION

The subject of the study is the management of economic security of enterprises in the context of digital transformations. Methodology. The research uses general scientific methods, in particular: theoretical generalisation; methods of analysis and synthesis and statistical analysis, and the graphical method to visualise the results of the study. The article is aimed at highlighting the results of a study of economic security management of enterprises in the context of digital transformations. Conclusion. The article analyses the economic security of enterprises in the context of global challenges. The impact of the war on the country's economy as a whole is underestimated and has far-reaching studies at both the macro- and micro-levels. It has been determined that at the beginning of the full-scale Russia's invasion on the territory of Ukraine, there was a significant reduction in the main economic indicators of enterprises' performance compared to the previous year. The analysis showed that the volume of products (goods, services) sold in 2022 decreased by 3,8 million UAH compared to the previous year, but remained at the level of the years before the pandemic, as well as the nature of the increase in business activity due to completely closed ports and an inadequate logistics system. At the same time, the number of business entities decreased by 223 thousand units, but their number only increased during the pandemic. It was noted that the acute shortage of personnel begins in 2022 with a significant decrease in the number of employees by 1,4 thousand persons. It was emphasised that over the past ten years, the number of employed workers has fluctuated around 8 thousand people and has not decreased, and in 2022 this figure was 7,5 thousand people. The economic security management system was improved, which is based on security levels and has a complex operating system that takes into account the external environment (customers, competitors, suppliers, etc.). A system for managing economic security in the context of digital transformation is proposed, based on the characteristics of the sublevels of security - financial, economic, social, information, environmental and security. It is emphasized that the main element of improving the economic security management system is to take into account the strengthening tools, such as risk insurance, forecasting, modelling, etc.

A simplicial epidemic model for COVID-19 spread analysis.

Networks allow us to describe a wide range of interaction phenomena that occur in complex systems arising in such diverse fields of knowledge as neuroscience, engineering, ecology, finance, and social sciences. Until very recently, the primary focus of network models and tools has been on describing the pairwise relationships between system entities. However, increasingly more studies indicate that polyadic or higher-order group relationships among multiple network entities may be the key toward better understanding of the intrinsic mechanisms behind the functionality of complex systems. Such group interactions can be, in turn, described in a holistic manner by simplicial complexes of graphs. Inspired by these recently emerging results on the utility of the simplicial geometry of complex networks for contagion propagation and armed with a large-scale synthetic social contact network (also known as a digital twin) of the population in the U.S. state of Virginia, in this paper, we aim to glean insights into the role of higher-order social interactions and the associated varying social group determinants on COVID-19 propagation and mitigation measures.