Real Elements Research Articles

Impedance measurement of rolling bearings using an unbalanced AC wheatstone bridge

Industry 4.0 drives the demand for cost-efficient and reliable process data and condition monitoring. Therefore, visualizing the state of tribological contacts becomes important, as they are regularly found in the center of many applications. Utilizing rolling element bearings as sensors and monitoring their health by the electrical impedance method are promising approaches as it allows, e.g., load sensing and detection of bearing failures. The impedance cannot be measured directly, but there are various methods available. This paper discusses advantages and disadvantages and suggests the AC Wheatstone bridge as a reliable way of measuring impedances with low phase angles at sampling rates in the kHz range. The corresponding equations are introduced, a simulation built, an uncertainty mode and effects analysis carried out and sample measurement results of real rolling elements shown. It can be demonstrated that the AC Wheatstone bridge meets the proposed requirements for sensory utilization and condition monitoring when the bearing is operated in the hydrodynamic regime.

Embodied Spaces in Digital Times: Exploring the Role of Instagram in Shaping Temporal Dimensions and Perceptions of Architecture

This study explores Instagram’s influence on sensory and experiential engagement with architecture in the digital age. Using a phenomenological approach, we studied the impact of Instagram’s visual features, such as filters, geotagging, and hashtags, on user interactions and perceptions of architectural spaces. The research demonstrates that Instagram transforms traditional architectural experiences into dynamic visual narratives that integrate real and virtual elements, altering our understanding of space and time. While acknowledging that architectural experience encompasses form, function, and historical context, this paper specifically focuses on Instagram’s role in mediating perceptual experiences. By analyzing user engagement patterns and content trends, the study highlights how Instagram shapes architectural design practices and the creation of spaces tailored for digital interaction. This study offers a comprehensive view of the complex relationship between digital media and architectural perception, identifying both the opportunities and challenges presented by the platform in influencing our understanding of architectural spaces.

Catch the Cyber Thief: A Multi-Dimensional Asymmetric Network Attack–Defense Game

This paper presents a novel multi-dimensional asymmetric game model for network attack–defense decision-making, called “Catch the Cyber Thief”. The model is built upon the concept of partially observable stochastic games (POSG) and is designed to systematically incorporate multi-dimensional asymmetry into network attack–defense problems. The attack agent is called a “thief” who wants to control a key host by exploring the unfamiliar network environment, and the defense agent is called a “police” who needs to catch the opponent before its goal is accomplished. The results indicate that the asymmetry of network attack and defense is not only influenced by attack and defense strategies but also by spatio-temporal factors such as the attacker’s initial position, network topology, and defense lag time. In addition, we have found that there may exist the “attack rhythm,” which makes “how to maintain a good attack rhythm” and “how to generate a robust defense strategy against different attackers” worth exploring. Compared with existing attack–defense game models, our game model can better generate a direct mapping relationship with real elements, enabling us to understand network attack and defense interactions better, recognize security risks, and design defense strategies that can directly serve real-world decision-making.

The Wake of HCE in Shaun the Postman: Duality, Sameness and Universality in James Joyce’s Finnegans Wake

James Joyce’s Finnegans Wake constitutes one of the highest artistic expressions of modernist literature in the English language. The novel’s departure from realist conventions and its intricate language invite challenging interpretations, fostering an exploration of the narrative in terms of an imitation or reimagination of reality. The distinctive nature of the protagonist’s family, embodying real and metaphorical elements, suggests a potential fusion among the different members. In this regard, this paper focuses on the interpretation of the main male characters – father and sons – as both diverse entities and a unified presence simultaneously, and on the potential rebirth of HCE into Shaun, revealing this fatherly-filial connection especially in the concluding chapters. Central to this exploration is the examination of the concept of “duality”, shedding light on the amalgamation and reimagining of characters into these separate and unified identities. The interplay of characters, particularly the twins, is interpreted as facets of a singular entity, portraying HCE embodying both and affiliating with various characters representing Shaun. Ultimately, the paper aims to unravel the complexities of HCE’s transformation into his son by dissecting the intricacies of duality, sameness and universality throughout the novel.

Effect of wavefront distortion on focusing performance of long-focal-depth mirror

Abstract A long-focal-depth mirror can produce a quasi-Bessel beam, which has the advantages of a long focal depth, a small spot, independence of wavelength, and a uniform longitudinal intensity. The laser beam emitted by a laser has a certain wavefront distortion, and real optical elements will also produce extra aberrations in the process of processing and assembling, which will then introduce new wavefront distortion to the optical system. Wavefront distortion will affect the phase and then affect the coherence and beam quality of the laser beam, ultimately affecting the beam focusing performance. To accurately study the effect of wavefront distortion on the focusing performances of long-focal-depth mirrors, an aberration model based on Zernike polynomials was established. Based on scalar diffraction theory, the effects of three typical aberrations on the focusing performances of long-focal-depth mirrors were calculated. The focusing performances were comprehensively evaluated by using various evaluation manners, including the power in the bucket. The calculation results showed that, compared with the ideal state, for an astigmatism or coma with a root mean square (RMS) more than 0.25 μm, the focusing performance of the long-focal-depth mirror dropped abruptly. The focused spot calculated with a 0.10 μm aberration shows a distribution identical to that when the component is properly clamped, exhibiting no significant aberration features, indicating that a RMS of 0.10 μm is acceptable.

СТІЙКІСТЬ ЗАЛІЗОБЕТОННИХ СТІЙОК ПРИ КОРОТКОЧАСНІЙ ТА ТРИВАЛІЙ ДІЇ НАВАНТАЖЕННЯ

The behavior of hinged support at the ends of the rack with initial bending under the action of load is considered. Spring rods are arranged symmetrically. The rack has an initial bend, compressed by forces constant in time. All real elements have one or another imperfections in the form of technological bends, therefore, they begin to bend from the very beginning of the load. The load, when it is exceeded even by an infinitesimally small amount, there is a loss of stability of this type of deformation, is called critical. In the calculation of stability under the long-term action of external forces, it is necessary to determine the load, at which the rate of movement in time monotonically decays. Solving the problem in such a setting is acceptable for systems, the development of movements of which in time leads to a change in the stress state. This condition for a compressed rack is fulfilled only in the presence of initial imperfections (initial bending, off-center application of compressive force, etc.). When solving the problems of the theory of stability, taking into account the creep of the material plays an important role. Creep can be limited in time or unlimited. When solving the problem of the stability of racks with initial imperfections, made of a material that has creep and reinforced with elastic rods, the following assumptions are made: 1) the hypothesis of flat sections is considered valid; 2) the deformations of the creeping material and the elastic rods at the points of contact are the same; 3) the modulus of deformations during stretching and compression are equal; 4) the creep material works in the stretched zone without the appearance of cracks. The relationship between deformations and elasticities in the material of the rack is established by a formula based on the linear relationship between deformations and elasticities. The creep rate of concrete is based on the hereditary theory of aging. In the work, an integro-differential equation was obtained - the equation of slow motion of the rod, expressions were obtained for the study of bends in any at what point in time, the formula for determining the critical force with long-term load action is derived.

Cities in electronic games: how they present and impact real urban areas?

ABSTRACT This study investigates the interactions between virtual cities in electronic (video) games and real urban environments, highlighting a significant gap in the literature regarding the influence of real cities on virtual counterparts and vice versa. Drawing on classical urban theories, it sets two primary objectives: to systematically review how real cities are represented in games and to explore the impacts of virtual cities on real urban areas. Through typological analysis, it identifies two pathways – form and function – through which real cities manifest in games, using specific cases like Cities: Skylines to illustrate these pathways. The principle for virtual city design is also outlined, with an emphasis on the “selection” and “subtraction” of real urban elements in designing processes. Additionally, it discusses how virtual cities impact urban tourism, fostering phenomena like anime pilgrimages, and urban planning, and enhancing public engagement in planning processes. Finally, this research contributes to some newly emerging theories such as Digital Twins by elucidating the interactive relationship between physical and virtual urban spaces.

Causal Fermion Systems and Octonions

AbstractThe authors compare the structures and methods in the theory of causal fermion systems with approaches to fundamental physics based on division algebras, in particular the octonions. It is found that octonions and, more generally, tensor products of division algebras come up naturally to describe the symmetries of the vacuum configuration of a causal fermion system. This is achieved by associating the real and imaginary octonion basis elements with the neutrino and charged sectors of the vacuum fermionic projector, respectively. Conversely, causal fermion systems provide octonionic theories with spacetime structures and dynamical equations via the causal action principle. In this way, octonionic theories and causal fermion systems complement each other.

Strengthening and embrittlement effect of cryogenic temperature on fiber reinforced geopolymer composite

Understanding the cryogenic behaviour of geopolymer composite (GPC) is essential to implement them in real structural elements at cryogenic temperatures. The paper presents a comprehensive investigation on the compressive strength, flexural behaviours, and energy absorption capability of both plain GPC and fiber-reinforced geopolymer composite (FRGPC) containing different fiber types and contents subjected to in-situ −170 °C. The results demonstrate that the compressive strength of plain GPC and FRGPC increases by 104.9 %–213.6 %, and the flexural strength increases by 73.4 %–212.5 %, exhibiting a significant cryogenic strengthening effect. Moreover, compared to flexural strength, compressive strength of GPCs displays a higher sensitivity to the cryogenic strengthening effect. The failure mode of FRGPCs changed from ductile failure to ductile-brittle failure at −170 °C, which is due to the decreased ductility induced by the cryogenic embrittlement effect. Additionally, cryogenic exposure has a greater impact on reducing the ductility of FRGPCs containing PP fibers than those with steel fibers. However, the negative effects of cryogenic embrittlement effect on ductility can be mitigated by incorporating steel fibers and increasing fiber content. The further analysis reveals that strengthening and embrittlement effect are associated with the increased cumulative energy and the sudden release of local energy, respectively. These findings contribute to the understanding of GPC performance at cryogenic temperature, which can guide the development of more resilient and durable GPC for cryogenic applications.

In Search of Treasure in Šalek: Creating Local Identity through Narrative Ostension

People transform concrete real-life events into narratives, but the reverse is also true; folklore and narratives in general can also provoke a creative or active response in people and significantly shape their worldview and way of life. The cases in which this happens (through processes of narrative ostension) are also of interest to folklorists, as they provide crucial contextual information about how (folk) narratives function, spread and acquire meaning. Stories about hidden or buried treasure are among the most important narratives that provoke such ostensive (re)actions. People who live with them sometimes venture out into the symbolically significant but very real elements of local space (e.g. castles) and actively search for the treasure mentioned in a legend. Such is the case of Šalek Castle (in Velenje), where local folklore about buried treasure has prompted several generations of locals to head up to the castle and start digging.

Efficient design of complex-valued neural networks with application to the classification of transient acoustic signals.

A paper by the current authors Paul and Nelson [JASA Express Lett. 3(9), 094802 (2023)] showed how the singular value decomposition (SVD) of the matrix of real weights in a neural network could be used to prune the network during training. The paper presented here shows that a similar approach can be used to reduce the training time and increase the implementation efficiency of complex-valued neural networks. Such networks have potential advantages compared to their real-valued counterparts, especially when the complex representation of the data is important, which is the often case in acoustic signal processing. In comparing the performance of networks having both real and complex elements, it is demonstrated that there are some advantages to the use of complex networks in the cases considered. The paper includes a derivation of the backpropagation algorithm, in matrix form, for training a complex-valued multilayer perceptron with an arbitrary number of layers. The matrix-based analysis enables the application of the SVD to the complex weight matrices in the network. The SVD-based pruning technique is applied to the problem of the classification of transient acoustic signals. It is shown how training times can be reduced, and implementation efficiency increased, while ensuring that such signals can be classified with remarkable accuracy.

The Postmodern Narrative Techniques in Tim O'Brien's "How to Tell a True War Story"

The Vietnam War had an irreversible negative impact on the United States, Vietnam, and the world at large. Its effects extended beyond geopolitics and seeped into the domain of literature, where numerous works have profoundly depicted and contemplated the conflict. Tim O'Brien's "How to Tell a True War Story" stands as a prime example of such literature, set against the backdrop of the Vietnam War. Drawing on Jean-Franois Lyotard's theory of postmodern metanarratives, this paper examines how O'Brien employs postmodern narrative techniques that diverge from traditional grand narratives to articulate the essence of his war fiction. Upon analysis, the paper contends that Tim O'Brien adopts the narrative mode of metafiction, blending narrative and commentary texts alongside real and fictive elements. By doing so, he seeks to alert readers to the constructed nature of both the textual and real worlds, encouraging them to perceive war through the lens of individuals' traumatic war experiences.

Numerical Analysis of Laminated Veneer Lumber Beams Strengthened with Various Carbon Composites.

Among the many benefits of implementing numerical analysis on real objects, economic and environmental considerations are likely the most important ones. Nonetheless, it is also crucial to constrain the duration and space necessary for conducting experimental investigations. Although these benefits are clear, the applicability of such models must be appropriately verified. This research subjected validation of numerical models depicting the behavior of unstrengthened and strengthened laminated veneer lumber (LVL) beams. As a reinforcement, a carbon fiber reinforced polymer (CFRP) sheet and laminates were used. Experiments were conducted on full-scale members within the framework of the so-called four-point bending testing method. Numerical simulations were performed using the Abaqus software. Two types of material models were examined for laminated veneer lumber: linearly elastic and linearly elastic-perfectly plastic with Hill's yield criterion. A distinction was made in the material properties of carbon composites based on their location on the height of the cross-section. The outlined numerical models accurately depict the behavior of real structural elements. The precision of predicting load-bearing capacity amounts to a few percent for strengthened beams and a maximum of eleven percent for unstrengthened beams. The relative deviation between numerical and experimental values of bending stiffness was at a maximum of seven percent. Applying the elastic-plastic model enables accurate representation of the load versus deflection relation and the distribution of stress and deformation of strengthened beams. Based on the findings, directives were provided for further optimization of the positioning of composite reinforcement along the span of the beam. Reinforcement design of existing laminated veneer lumber members can be made using presented methodology.

Virtual Reality (VR), Augmented Reality (AR) and Mixed Reality (MR), A Necessity of The Modern Diving Technology

Abstract The paper looks at three emerging technologies, namely virtual reality (VR), augmented reality (AR) and mixed media (MX), and explains how they are transforming the way we interact with the digital and real worlds. Each technology is defined and the main features are highlighted for comparison. VR gives us a complete and immersive experience in the virtual world, AR adds digital elements to the real world, and MX integrates both media to create an interactive experience where virtual and real elements interact and coexist. Within the work a number of equipment or applications incorporating these emerging technologies were reviewed to highlight how they could assist divers to train under controlled conditions and simulate real diving conditions in hazardous or complex environments. The implementation of technologies such as virtual reality (VR), augmented reality (AR) and mixed media (MX) within the Diving Center of the Romanian Naval Forces would bring many advantages and significant improvements in terms of the training capacity, operational efficiency and safety of military divers. These technologies would not only modernize training and operations, but also strengthen the ability to intervene and react in critical situations.

Magic Realism in Rabindra Sameer's Mrityuko Aayu

This article analyzes the novel Mrityuko Aayu in the light of Magic Realism. Applying magic realism is methodological approach for critical analysis of the novel in this article. It follows interpretive textual analysis. Free translation has been used while taking the citation from the novel. I have drawn the conclusion that the novel is a magic realist novel as it has introduced innovative style of narrating the story. The story begins from the death of the protagonist, but he is capable of seeing everything even after the death. It has blended mundane and supernatural, ordinary and extraordinary and real and fantastical elements in an unquestionable way. The novel's extracts are analyzed within five parameters that include fantastical elements, real world setting, incorporation of myth, meta-fiction and social/ political critique. Even after the death of the protagonist, the story moves ahead from the spirit's perspective. The spirit is capable of seeing, feeling and experiencing everything. The readers accept all such actions and happenings as normal without questioning the reliability of them and feel sorry for his painful and pathetic condition. Therefore, the writer is successful in using magic realism in the novel. It is hoped that this article will encourage researchers to study other works of fiction from the point of view of Magic Realism.

Metaverse: a new reality in surgery. Review

The metaverse is a relatively new concept in technological advancement. It is a three-dimensional immersive environment including real and virtual world elements, in which various digital agents, more precisely, avatars, interact with each other and various activities (educational, cultural, and financial) can be carried out. It is an emerging controversial concept without precise definition and will likely continue to evolve as technology improves. Works of literature from 2020 to 2023, posted in the PubMed and Web of Science databases, were extracted using the following keywords: “metaverse”, “education”, “digital therapy”, “interdisciplinary consultation”, “medical Internet of things”, “virtual reality”, “superimposed reality”, “extended reality”, “mixed reality”, “lifelogging”, “mirror world”, “digital twins”, and “surgery”. In the PubMed search using the original terms, no publications were extracted in 2020, 9 in 2021, 161 in 2022, and 246 in 2023. In the healthcare context, metaverse technology refers to the use of virtual reality and interactive and other immersive technologies, such as augmented reality, to create simulated environments intended for training, education, and clinical applications. Various aspects of medicine such as digital therapeutics, multidisciplinary team discussions, medical Internet of things, surgical simulations, conferences and meetings, research programs, etc., are being explored. Depending on the requirements, the metaverse provides a versatile platform that can be modeled accordingly, providing a flexible tool for medical development. In this review, we discussed in detail the possible applications of the metaverse in surgery. All scoping rubrics are based on the sparse evidence in the scientific literature and are adequately evaluated to provide compelling evidence on the utility of the metaverse in the future of medicine.

Blurring Boundaries: Real and Hyperreal Elements in Daniel Kehlmann’s Measuring the World

The academic paper centers on evaluating the real and hyperreal elements in the German novel Measuring the World(2005) written by Daniel Kehlmann. The novel is set in Germany in the seventeenth and eighteenth centuries, during the Enlightenment era, and bears a resemblance of the prominent figures of real time, namely the mathematician Carl Friedrich Gauss and the geographer Alexander von Humboldtof the same centuries. The historical description of these prominent figures undergoes alteration, and the writer adds several dramatic events to it. This research paper attempts to analyse the theory of hyperreality by the French theorist Jean Baudrillard. The paper also highlights the concept of Simulation that Kehlmann employs in altering the reality with representations. In further, the paper aims to provide an understanding of the examination of narration, character development, and exaggerated events exploring the multiple-layered narrative.

Non-deterministic method for semi-automatic calibration of smartphone-based OST HMDs

An Augmented Reality (AR) system must show real and virtual elements as if they coexisted in the same environment. The tridimensional aligment (registration) is particularly challenging on specific hardware configurations such as Head Mounted Displays (HMDs) that use Optical See-Through (OST) technology. In general, the calibration of HMDs uses deterministic optimization methods. However, non-deterministic methods have been proposed in the literature with promising results in distinct research areas. In this work, we developed a non-deterministic optimization method for the semi-automatic calibration of smartphone-based OST HMDs. We tested simulated annealing, evolutionary strategy, and particle swarm algorithms. We also developed a system for calibration and evaluated it through an application that aligned a virtual object in an AR environment. We evaluated our method using the Mean Squared Error (MSE) at each calibration step, considering the difference between the ideal/observed positions of a set of reference points and those estimated from the values determined for the calibration parameters. Our results show an accurate OST HMD calibration for the peripersonal space, with similar MSEs for the three tested algorithms.

Virtual array element beamforming algorithm based on LSTM neural network

Virtual array element beamforming technology can improve the angular resolution of conventional beamforming algorithm. However, when the number of real array elements is limited, the beam pattern of the virtual array element beamforming algorithm based on linear prediction(the VAEBF-LP) is slightly distorted, the root mean square error(RMSE) of Direction of Arrival(DOA) is larger and so is the main lobe width. In response to this problem, A virtual array element beamforming algorithm based on the LSTM neural network(the VAEBF-LSTM) is proposed. This algorithm uses the LSTM neural network to learn the temporal characteristics between the received data of real array elements and the virtual array elements. Obtaining the received data of virtual array elements, this algorithm enables the beam pattern to be free of distortion and achieve higher angular resolution detection of targets with a relatively low RMSE of DOA in this context. The simulation results show that the VAEBF-LSTM not only makes the beam pattern distortion disappear but also makes the main lobe smaller in width than that of the conventional beamforming algorithm with the guarantee that the RMSE of DOA remains considerably low when the number of real array elements is limited.

Семантические особенности квазиантропонимов в текстах англоязычных фэнтезийных видеоигр

The article presents an analysis of the semantic parameters of quasi-anthroponyms utilized in English-language accompanying texts for fantasy computer games. As a first step, we developed an approach to clarify the term quasi-anthroponym, which had been subject to various interpretations in scholarly publications. Quasi-anthroponyms are defined here as names of animated fictional objects that function as characters within the virtual worlds of video games. Taking into account the correlation between real and fictional elements, fantasy characters are categorized based on the degree of their fictionality. Quasi-anthroponyms naming characters of highly fictional game universes are classified into three major groups according to their semantic potential. The primary semantic parameters underlying this classification include indications of the character’s appearance, specific characteristics and combinations of certain features, such as the character’s functions in the game universe. The significance of this research lies in expanding the field of anthroponymic studies by incorporating relevant language material from virtual game discourse. Moreover, the practical implications are demonstrated through the potential use of these findings in lectures and seminars on contemporary English lexicology and stylistics, as well as in the analysis of texts of fantasy video games in language teaching. This aligns with the growing trend towards gamification of modern educational practices. Ultimately, this study establishes substantive criteria underlying the creation of English-language names for fictitious characters in the realm of fantasy video games. In addition, inventorization, systematization and classification of these linguistic units were conducted.