Technical Objects Research Articles

Formulation of the problem of structured-element modeling of jet interference in a nozzle block

The objects of research are supersonic composite jet flows, as well as structural elements of flows (shock and acoustic waves, gas dynamic discontinuity surfaces), which act with each other and with various technical objects. Such objects may be structural elements or parts of special technical systems that experience loads during operation, or are subjected to targeted effects in order to improve their mechanical properties. The research is carried out in order to develop mathematical models describing the interaction of structural elements of the flow supersonic gas jets among themselves in composite jets. When performing the work, various methods allowing to model gas-jets flows and processes are considered. To solve the problem method of structured- element modeling of gas-jet processes was chosen [1–4]. This method focused on the creation of engineering methods for calculating launch gas-dynamics problems. The scope of application of the method can cover not only space roket, also civilian industry is in part where they face the problems of jet flow. For example with the need to improve the reliability of products, their strength and metal characteristics. The direction of subsequent theoretical and experimental research, which determine the development of the structural-element method, are determined and clarified.

THE PLACE OF INSULATION COATINGS IN ENSURING RELIABILITY STEEL UNDERGROUND GAS PIPELINES

The article examines the issue of the place and role of insulating coatings in ensuring the reliability of steel underground gas pipelines. It has been shown that insulation is the main, basic means of protection against corrosion. A reliability model has been proposed for a linear section of a steel underground gas pipeline as a complex technical system consisting of unequal elements: a steel pipe as the main element that determines the operability/inoperability state of the system, and auxiliary protective elements – insulation and electrochemical protection, which reduce the level of corrosive effects of soil on the main element. This increases the degree of similarity of the reliability model to a real technical object, and also makes it possible to build a hierarchical structure of faults of various elements, taking into account their impact on the overall technical condition of the gas pipeline. It is proposed to consider its integrity as the determining physical parameter of the protective coating; the degree of preservation (loss) of integrity and the onset of the limiting state of the insulation should be assessed by the number (density) of defects.

Telluric geographies of the means of violence. On alterity, weapons, and space at the margins

This article provides a critical reading of the literatures on spaces at the margins of different polities and state/non-state forms of authority in political geography asking how infrastructures of violence are governed. In this ambit, weapons and military means have been poorly defined and conceptualised, while the ways they are actually governed (beyond a mostly instrumentalist perspective), as well as the effects this govern-mentality activity generates for the reproduction of (dis)orders at the margins, have not been directly investigated. Drawing from studies on biopolitical governmentality, and Roberto Esposito's conceptualization of the immunitary apparatus in particular, we explore how relations of alterity, as well as attendant political spaces, are terraformed through violence and infrastructures of governing weapons and military means. Our approach is attentive to the role of materiality and non-human elements in shaping socio-spatial relations but it highlights also how there exists a close link between (1) weapons and armed humans, (2) space, and (3) identity/alterity which is articulated via the act of governing infrastructures of violence. Building upon empirical insights from Myanmar's borderlands and frontiers, the paper shows that weapons and war-making are governed through infrastructures made of technical objects codifying violence materially, techniques of managing human-non-human entanglements, and rationalities. Conducting the conduct of violence contributes to reproduce the political space at the margins and to construct identity/alterity categories founded on the identification of less-than-human forms of life.

Effect of cryogenic conditions on the critical crack tip opening displacement for the laminated material AA2519-AA1050-Ti6Al4V-T62

In the case of operating technical objects in conditions that accelerate material wear, it is necessary to adequately protect the object from the aggressive working environment. There are several possibilities, ranging from applying surface coatings (paint, varnish, galvanic layers) to the use of composites. An example of such a material is a composite formed by explosively welded AA2519, AA1050, and Ti6Al4V alloys. Since the described material is relatively new, its mechanical properties are still being determined. Therefore, in this article, the results of research and their analysis regarding the fracture toughness of the described composite in comparison to the fracture toughness of the base materials in the selected range are presented. The main objective of study was to determine the crack tip opening displacement (CTOD) values for the AA2519-AA1050-Ti6Al4V laminated material explosively welded under ambient and cryogenic conditions. The tests were carried out to determine the effect of the aforementioned temperature conditions on selected properties of the tested laminated material. This paper presents the theoretical basis and the adopted testing methodology. The experimental results obtained and their analysis are also presented. Thanks to the analysis, the effect of cryogenic conditions on the value of the crack tip opening displacement was observed. Moreover, the state of knowledge presented in earlier publications on crack tip opening displacement determination for base materials, i.e. AA2519 and Ti6Al4V, has been extended. The paper also presents a CTOD determination procedure for laminated material based on the knowledge on the mechanical properties of the base materials.

Quantitative analysis of aviation incidents: A comprehensive study on bird strikes and safety improvement opportunities

Safety in aviation has various connotations. According to the International Civil Aviation Organization (ICAO), it is a state in which the possibility of harm to people and property is minimised and maintained within a continuous process of identifying threats and managing safety risks at an acceptable level or below an acceptable level. Actions related to threat identification can be reactive, proactive, or predictive. Reactive actions aim to verify what happened, why, and how to prevent it from recurring. For this purpose, incidents that occurred in the past are analysed. By Polish law, the Commission for Investigating Aviation Accidents investigates accidents and serious incidents, while incidents mostly fall under the responsibility of the aviation organisation in which the incident occurred. Therefore, this article aims to identify threats causing incidents. Three thousand two hundred aviation incidents reported between 2017 and 2022 to the Civil Aviation Office as part of the mandatory and voluntary event reporting system were analysed. The identified causes, due to the diversity of their description, were divided into four groups. The first group consists of human factors, representing inadequate actions by pilots, crews, or individuals who caused a situation of danger. The second group comprises errors in the operation of technical objects, including aircraft. This group also includes situations where foreign objects violate airspace or minimum conditions are breached. The next group includes environmental causes such as wild animals, birds, and weather conditions. The last group consists of procedures related to flight phases.

Improvement of the uniformity of the magnetic field inside a short solenoid by the end winding system

Improving the level of homogeneity of the magnetic field in the middle of the working volume of a short solenoid makes it possible to improve devices for demagnetizing technical objects and studying the magnetic properties of materials. One of the means of increasing the level of homogeneity of the magnetic field in the middle of the solenoid is to approximate the shape of its winding to the closed surface. The use of a system of a solenoid and two end axisymmetric current windings with a common current source is proposed as such a surface. A mathematical model of the scalar potential of the magnetic field of such a system was built using spherical harmonic analysis, and functional dependences of the current density on each surface were obtained for its first harmonic, which is the dipole component of the magnetic field. Formulas for calculating the number of turns in the end windings and the geometric parameters of their arrangement and the simulated total magnetic field inside the proposed system are obtained. A comparative analysis of the homogeneity of the magnetic field created by a separate solenoid and a solenoid with end windings, depending on the geometry of the system, was conducted. The use of end windings significantly improves the uniformity of the magnetic field near the ends, especially on the axis of the solenoid. Due to this, the efficiency of the end windings significantly depends on the solenoid elongation indicator and allows you to increase the working volume by 5-20%, depending on this indicator. The proposed system makes it possible to obtain a magnetic field with a maximum deviation of 5% from uniformity for a solenoid elongation index of 2. As the elongation increases, the efficiency of the end windings decreases and for systems with an elongation of 10 or more, their use becomes impractical. The results of the analysis testify to the effectiveness of using the proposed system in devices for demagnetizing technical products that differ in a small indicator of the elongation of the working solenoid - primarily devices that create a uniform magnetic field with an amplitude decreasing over time of 240 A/m and are used in particular to remove soft residual magnetization from elements of space vehicles

Modelling the Reliability of Logistics Flows in a Complex Production System

This paper analyses the disruptions occurring in a production system determining the operating states of a single machine. A system with a convergent production character, in which both single flows (streams) and multi-stream flows occur, was considered. In this paper, a two-level formalisation of the production system (PS) was made according to complex systems theory. The continuity analysis was performed at the operational level (manufacturing machine level). The definition of the kth survival value and the quasi-coherence property defined on chains of synchronous relations were used to determine the impact of interruption of the processed material flow on uninterrupted machine operation. The developed methodology is presented in terms of shaping the energy efficiency of technical objects with the highest power demand (the furnace of an automatic paint shop and the furnace of a glass tempering line were taken into consideration). The proposed methodology is used to optimise energy consumption in complex production structures. The model presented is utilitarian in nature—it can be applied to any technical system where there is randomness of task execution times and randomness of unplanned events. This paper considers the case in which two mutually independent random variables determining the duration of correct operation TP and the duration of breakdown TB are determined by a given distribution: Gaussian and Gamma family distributions (including combinations of exponential and Erlang distributions). A formalised methodology is also developed to determine the stability of system operation, as well as to assess the potential risk for arbitrary system evaluation parameters.

Нейросетевые технологии в проектировании систем управления на предприятиях АПК

The paper introduces a comprehensive review of various approaches to using neural networks in the design of control systems for closed-end agricultural facilities. The empirical part of the study featured technical statistics of agro-industrial enterprises. It applied trained neural networks to agricultural enterprise data for prediction purposes. The resulting root mean square error was 0.120, and the standard deviation did not exceed 0.093. Neural networks proved efficient as part of specialized software for monitoring technical objects of the agro-industrial complex and predicting their development.

Reaching for T in the South African archives

AbstractThis article proposes a methodology of reaching in historicity. It does so by tracing the technical object of synthetic testosterone as it has been used by trans people for gender affirming care. To show the usefulness of the method, this article employs it first in relation to mentions of synthetic testosterone in the South African Medical Journal as a primer to understanding its relationship to the state and the law in South Africa from 1963 to 2003, reaching an apex in the Cape Town Transsexual/Transgender Groups advocacy for self‐identification, much of which hinged on the role of synthetic testosterone.

Algorithm for Calculating Reliability of Single Linear Section of Steel Underground Pipeline

One of the most widespread technical systems in the world is underground steel pipeline communications (heat pipelines, main and distribution oil and gas pipelines, etc.). Accordingly, reliability assessment of such technical systems and their components is of great theoretical and practical interest. At the modern level of development, reliability calculation has become a mandatory stage in the design and diagnostics (during operation) of any technical systems in ge-neral, and in particular pipeline systems. A reliable calculation, either explicitly or implicitly, is always based on the model of the object being calculated. It is the adequacy of the model to the real physical relations and processes inside the technical object that determines the accuracy and practical value of calculation methods. It is proposed to consider a single linear section of an underground steel pipeline as a complex technical system of unequal elements from the point of view of reliability – the main element (steel pipe) and auxiliary protective elements combined into subsystems (blocks). The algorithm for calculating the reliability of the object is based on the method of block diagrams, taking into account the influence of the aftereffect of the failure of an auxiliary element (elements) on the reliability parameters of the main element, which more adequately reflects the specific features of the design and operation of steel pipelines compared with the applied static models. The variants of structural design of a steel underground gas pipeline with a protective insulation coating and with complex corrosion protection (insulation and electrochemical protection) are considered, for which refined formulas are obtained for calculating the main reliability (failure-free) indicators.

Should we be afraid of dental robots?

As it seems likely that France, at the forefront in the use of surgical robotic platforms, will authorize the deployment of dental robots in the short term, the purpose of this article is to question what is at stake in this technological revolution, for dental professionals, regulators but also (and above all) for patients: what awareness-raising will the intervention of machines bring? How does robotics reshuffle the cards of the care relationship? What are the ethical and public health issues? After having defined dental robots as non-humanoid, automated surgical devices with exclusive restorative vocation, we will see how the field of dental robotics currently oscillates between hopes and illusions. We will describe the new responsibilities and ethical requirements related to the introduction of these AI-powered technical objects, as well as the necessary safeguards that have to be implemented in order to avoid any moral buffer and to protect patients from any robotization (literally or metaphorically in the sense of ‘zombification’). Finally, we will show that ultimately the question of robot-dentists is the natural evolution of unreasonable application of industrial processes to the rationalization of health and ectopic, neo-liberal practices shifting healthcare into a commercial commodity. Patients can participate in reversing this trend, by recalling that the centrality of the human person is the cornerstone of health professions.

Construction of automated optimal control systems with elements of artificial intelligence

<span lang="EN-US">This article examines the widespread introduction of artificial intelligence technologies, means of their implementation and support as a determining factor in the development of scientific and technological progress. On this basis, various advanced objects of various functional purposes are created, which are characterized as “smart”. Their distinguishing feature is the ability to implement a “reasonable” way of functioning, taking into account the prevailing circumstances. This ability is expressed in the fact that in the object automatically, i.e., without human participation, or with minimal human participation, the most rational or optimal modes of functioning are supported, the definition of which involves the performance of operations containing signs of rational activity. This “smart” behavior of technical objects is mainly determined by the “intelligent” functioning of the control systems built into them. In particular, intelligent automated systems for optimal control. In accordance with this, the development of new approaches and methods that expand the possibilities of building such control systems should be considered as an urgent and priority task.</span>

MODELING OF INTELIGENT SOFTWARE FOR THE DIAGNOSIS AND MONITORING OF SHIP POWER PLANT COMPONENTS USING MARKOV CHAINS

The reliability and serviceability of metal structures depends on the quality of control over the technical condition and mechanical properties of materials in accordance with international standards. However, in the course of operation, deviations from the normative values of material properties occur due to the uncertain nature and magnitude of the loads, which necessitates periodic shutdowns of the equipment for the purpose of diagnostics. Uninterrupted operation of elements of power equipment of marine vessels depends on the quality of control of their technical condition by physical diagnostic methods. The most effective method of reducing operating costs and increasing the reliability of equipment is maintenance based on interactive monitoring of its condition, detection of malfunctions and forecasting of energy equipment parameters. This makes the tasks of control, diagnosis and forecasting of energy equipment parameters particularly relevant. At the same time, the use of various diagnostic methods does not allow taking into account all the features of real operating conditions. This problem is especially acute in conditions of various extreme situations and peak loads, which cannot be taken into account. Probabilistic methods, in particular Markov chains, are a promising area of research. The system of intelligent diagnostics and monitoring of ship power plant turbochargers using Markov chains is presented. The novelty of the developed methodology lies in replacing discrete time intervals of the diagnostic process with a sequence of states of technical objects. In this formulation, Markov chains represent a synthetic property that accumulates diverse factors. Randomization of stochastic diagnostic and monitoring processes of ship power plant components enables an increase in reliability of equipment under severe operating conditions. The results of calculations of digitalization of experimental data, calculations of transition matrices and construction of an orgraph allowing to study the kinetics of damage accumulation in real time are presented.

Structural and Parametric Synthesis of Neural Network Controllers for Control Objects with Limiters

The article presents a methodology for the synthesis of digital control systems for nonlinear objects with limiters under conditions of incomplete information. Closed-loop tracking systems with negative feedback are considered. Artificial neural networks are proposed to build a controller, which is included in series with the control object. This approach is effective when known classical methods do not allow to synthesize control. This is the case, for example, if the mathematical model is essentially nonlinear and is not fully defined. The developed methods allow us to expand the class of technical systems, for which the direct (without using various kinds of simplifications) synthesis of control laws that are close to optimal is possible. In addition, neural network controllers possess the properties of robustness, adaptivity, and are initially digital, i.e. those qualities, which are very much in demand in practice. In article main attention is given to such problems, as a choice of neural network structure for neural simulator and neural controller, construction of training sample, ensuring convergence of the process of weights correction. For training neural networks the method of back propagation of error is used as a basic one. The effectiveness of the proposed technique is demonstrated by the example of the synthesis of a neuroregulator for a specific technical object and its comparison with classical control systems. It should be noted that today neural network technologies are widespread enough in various spheres of activity. The successes demonstrated in sound processing, image processing, automatic translation, in navigation systems, in big data processing are impressive. However, their application in automatic control systems is not so widespread. The authors of this article believe that the potential of artificial neural networks can be used in this direction. It should be understood that the use of neural networks is effective only under certain conditions and properties of the control object.

Metapresentiality: a foundational concept for a critical theory of digital health.

In this text, I propose the concept of "metapresentiality" as a fundamental element for a Critical Theory of Digital Health. First, I present the concepts of technique, technology, and technical object, central to the theories of Álvaro Vieira Pinto and Milton Santos. Secondly, based on Luciano Floridi's philosophy of information, I question the relevance of the dichotomy real-material-concrete vs. digital-virtual-informational as an ontological foundation for concepts of reality, place, and presence, highlighting the notions of virtual reality and extended reality. Thirdly, I introduce an etymological-historical critique of the series presence-telepresence-metapresence, focusing on the emerging notion of meta-presentiality in the form of proto-concept and its eventual formalization as a conceptual foundation for a socio-technical appropriation and technosocial integration of digital technologies. Finally, I discuss Digital Health as a field of knowledge, techniques and practices and evaluate epistemological and pragmatic advantages of metapresentiality as a concept in the fields of computing, education and health.

Share and erase: agency formation among children and adults with mental disorders

The article offers a description and analysis of agency formation practices in the Center for the Development and Socialization of Children and Adults with Disabilities. The research focuses on the interaction between the center’s psychologists and wards, mediated by various artifacts and technical objects. I show that the formation of agency can be subdivided into several aspects: first, assistants create the locality - a spatially and temporally limited interactional environment of heterogeneous actors; second, the life of the center depends on the arrangement of the actions of these heterogeneous actors; third, psychologists erase traces of non-human actors’ work to perform agency; this procedure allows to highlight an action that will later be attributed to the wards. This attribution must be seen as a final stage of the work performed within localities. Thus, within the center, agency manifests itself as an effect that occurs when the actor becomes inscribed in the locality, forced to share the common place with other actors, reduced to its action.

Control Systems Synthesis of Maximum Robust Stability Degree Based on Vertex Critical Root Diagrams

The article solves the problem of operative selection of the redundant onboard equipment complex components configuration of the suitable in the current operating conditionаs in the interests of ensuring high fault tolerance of the complex, as well as achieving other operational and technical characteristics. The basis of the redundancy management system of the complex consists of configuration supervisors — as program subjects according to the number of its competitive configurations of heterogeneous and nonuniform equipment worked out in advance. The choice of the preferred configuration is proposed to be carried out by performing multi-level arbitration, which includes two phases of paired arbitration of computers and paired arbitration of configuration. It is proposed to include the means of both types of arbitration in each configuration supervisor, which ensures its self-sufficiency when participating in a competitive selection. The second part of the article is devoted to the computer’s arbitration for the implementation of redundancy management functions. The approach is applicable to a computing environment with many comparable computing devices and contains 2 phases. In the first phase, a preliminary selection of a competing pair of computers — as applicants for the implementation of redundancy management functions in them is carried out. In the break between the phases, the pair computers implement the procedures for pair arbitration of configurations given in the first part of the article. In the second phase, the final choice of the -computer is made, in which the supervisor who won the arbitration will be implemented. In order to achieve the maximum possible centralization of selection procedures and, as a consequence, the exclusion of " bottlenecks" in terms of reliability of places, additionally proposed: the organization of secure data exchange between computers based on distributed registry technology; the procedure of paired arbitration of computers, consisting in mutual cross-validation of dominant supervisors of a pre-allocated pair by comparing preference matrices, including information parcels of arbitration objects. A methodological example that demonstrates the features of the system functioning in the conditions of computers degradation is given. The proposed approach can be used to solve the problems of reconfiguration control of heterogeneous computing facilities of technical objects on-board equipment complexes.

Corrupting data and sensing error, or how to ‘see’ digital images

In response to calls to forget and unthink photography this article considers the computational environment and its consequences for the image making. What is there to know about images that are networked and generated with data processing techniques rather than with light and chemistry? How to analyse images and read what they are and what they represent, beyond what is visible in the picture? The article argues that glitches while aesthetically capturing errors in the machine point to broader conditions of image making revealing systemic errors and not only its momentary technical failures. To explore digital images as affective phenomena to be sensed, the article looks at how glitch and its operations have been used by artists to generate digital images, and most importantly how they reveal computational systems as technical objects and affective infrastructures where discrimination is not an error but part of the system.

Technology of creating educational content for open digital resources in general technical disciplines

The article presents the technology of creating educational content for open digital resources in general technical disciplines that consist of the four stages: development, design, posting and final. There are proposed to create video, interactive and graphic educational content in the context of the proposed technology at the development stage. Video content is presented in the form of video lectures, video instructions for practical and laboratory tasks, video recording of the educational results. Interactive content is introduced by lectures and laboratory tasks with interactive elements, interactive posters or tests. Graphic content is provided by lectures with graphic models of the technical objects, practical tasks with the use of modelling and design programs, creation of 3D models for laboratory works and performing engineering and technical projects. The design stage includes the selection of services for the specific type of content and creation the tasks for open digital resources. Educational content is implemented in an open digital resource by obtaining a link, QR or implementation code at the posting stage. The final stage of the application of the proposed technology involves the performance of tasks by higher education applicants, obtaining points, acquisition of competencies. The Pearson criterion was used to statistically verify the application of technology of creating educational content for open digital resources in general technical disciplines. The higher education applicants in the experimental group received higher results than in the control group which may indicate the effectiveness of the outlined technology.

Detailing the idea of the design process of hydraulic automation objects

The work is touched to the design methods of the complex technical objects. The reason of the objects complication is the requirement of the dynamical processes coordination because the planed characteristics are needed. The main design stages idea – circuit diagram – simulation – structure are considered. The means of the design stages information representing of traditional approach are the relatively commonly and not consistent. It leads to design time increasing. In this work to structure the design information, coordinate the means of the different stage information representation with each others and detail design process are proposed. To do it the common information space of knowledge of the subject aria are separated on the streams. The streams represent information about the content, uniting, activities and requirements. The design process is represented as the transactions chain. Each transaction is based on the named streams and successively forms the state of the resulting functional stream. These states reflect the readiness levels of the designed object. Due to this way of means representation and detailing of information the coordination between different stages was provided. There are the possibilities to check the stage correctness executing also. As result the iteration reducing and time consumption of the design process are reached. The design process is illustrated by the example.