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A new type of engine is proposed. The principle of the operation of this engine is as follows. The alternating electric current of high frequency flows from the condenser over the vertical conductor of the cross and branches at its centre in three directions. The vertical current generates a magnetic field. The horizontal currents flow in counter‐directions; therefore their magnetic fields are mutually cancelled, but the side branches of the cross are subjected to the operation of the Ampere force (F) from the magnetic field of the vertical conductor. This force moves the engine forward.

This study aims to investigate the effects of firm- and governance-specific characteristics on digital trust (DT) and firm value. Firm-specific factors include return on assets (ROA), market-to-book ratio (M/B ratio), size and leverage, whilst governance-related factors comprise board size, percentage of female board members, board independence and institutional ownership. All listed US firms over the period of 2011–2016 were analysed in this study.

This study provides a novel method to empirically measure DT by combining multiple variables to create a combined DT score. The variables include security and privacy scores, security rankings and data breaches, amongst others. Subsequently, a linear regression was performed to evaluate the effect of firm- and governance-specific characteristics on DT, as well as the effect of DT on firm value.

By using signalling theory, this study finds significant evidence that a firm’s profitability (ROA) decreases whilst its size increases DT. This could be due to the fact that firms with lower DT monetise data more actively, decrease DT and increase short-term profitability. Significant evidence also shows that increasing DT leads to an increase in firm value.

Although numerous studies have been conducted on developing customers’ trust by incorporating corporate social responsibility to improve firm value, the literature remains still on its digital analogue. Therefore, this study extends the knowledge of corporate digital responsibility (CDR) by providing a novel method for calculating DT across industries as an antecedent of CDR. Specifically, it sheds light on how firms can enhance DT by utilising firm- and governance-level factors. This enhanced DT can subsequently increase firm value. The study provides important managerial implications by providing empirical evidence that cybersecurity investments increase firm value. This value increase is related to the rise in shareholder value amongst investors and the increase in the organisation’s consumer perceptions as the latter’s interests are better managed.

This study aims to examine the feasibility of feedforward actuation of the recoater blade position to alleviate the resin surface non-uniformity while moving over deep-to-shallow transitions of submerged (already cured) geometric features.

A two-dimensional computational fluid dynamics (CFD) model has been used to determine optimized blade actuation protocols to minimize the resin surface non-uniformity. An experimental setup has been designed to validate the feasibility of the proposed protocol in practice.

A developed protocol for the blade height actuation is applied to a rectangular stair-like configuration of the underlying part geometry. The evaluation of the actuation protocol revealed the importance of two physical length scales, the capillary length and the size of the flow recirculation cell below in the liquid resin layer below the blade. They determine, together with the length scales defining the topography (horizontal extent and depth), the optimal blade trajectory. This protocol has also shown its efficiency for application to more complicated shapes (and, potentially, for any arbitrary geometry).

This study shows that incorporation of a feedforward control scheme in the recoating system might significantly reduce (by up to 80%) the surface unevenness. Moreover, this improvement of performances does not require major modifications of the existing architecture.

The results presented in this work demonstrate the benefits of the integration of the feedforward control to minimize the leading edge bulges over underlying part geometries in stereolithography.

Cities’ population growth goes in hand with the development of new technologies that are becoming the key factor of the Smart City (SC) concept. It allows the implementation of efficient management solutions, operation, and sustainable development of a city to face the challenges of urbanization and improve the services for the citizens and visitors.

The concept of the SC 5.0 was first presented in Svítek, Skobelev, and Kozhevnikov (2020), where the problems of the complexity of current cities due to rigid management processes, variety of infrastructure, and SC modules, systems, subsystems, and applications were described.

To prove the concept, several practical examples were developed to cover the topics: modeling in SCs, practical implementation of multiagent technologies, the approach of creating city ontology and the city knowledge base as the instrument of semantic interoperability, and visualization possibilities of Smart Evropská as a SC Testbed used for teaching purposes.

The new organizational structure is proposed based on knowledge graphs, and practical examples are shown. The applicability of knowledge graphs to be used in combination with data management platforms for monitoring SC key performance indicators (KPIs) and providing interoperability of services is presented.

This paper aims to explore the fluid flow in the stereolithography process during the recoating step. The understanding of the flow dynamics can be used as an input for an active control of the resin surface height map. The recoating over a rectangular cavity has been considered to investigate the influence of the cavity depth on the resin surface height map.

Two-dimensional numerical simulations have been used to obtain the flow characteristics as function of the cavity depth. An experimental setup, which mimics the recoating process in the stereolithography process, was used to verify the results of simulations and to test the suitability of the 2D model. The surface height profile along the centreline was measured by a confocal chromatic distance sensor and compared to the 2D numerical results.

By means of computational fluid dynamics (CFD) simulation, the flow in the cavity and the free-surface behaviour of the resin was explained for different cavity depths and confirmed by experiments.

The study is focused only on the cavity depth variation to show feasibility and suitability of the presented CFD model and the proposed analytical expression to estimate the layer thickness.

The proposed approach can serve as a tool for designing the closed-loop control for the recoating system in the next generation of stereolithography equipment.

In the present work, the fluid flow behaviour, a source of significant imperfection in the recoating process, has been investigated during the recoating step over a rectangular cavity.

Adopting a dual processing cognitive perspective, this study explores the decision-making processes past the start-up stage that small entrepreneurial businesses employ to grow. The author examines how entrepreneurs evaluate and make decisions on growth opportunities in their business environment. The author uses cognitive style as a theoretical lens to capture differences in information processing, combining interviews and psychometric questionnaires to analyse cognitive styles. The longitudinal mixed methods approach illustrates the richness of the entrepreneur’s decision-making process, which the author tracks over a two-year period. The author determines how intuitive and analytical cognitive styles are used by entrepreneurs and the contribution these styles make to decision-making. The findings show that the two cognitive styles are versatile as entrepreneurs adjust and adapt their cognitive style over time, in keeping with the situational factors of their business environment. The author also finds marked differences between novice and mature entrepreneurs and that experienced entrepreneurs exhibited greater levels of cognitive versatility, which was directly linked to their prior experience. The study has significant implications for future research, which should consider the question how an entrepreneur’s cognitive style is dependent on the business context and their prior experience.

Cities evolved into quite complex urban systems. The rigid management process must reflect the complexity of the current political, social, and economic environment. With the vast city growth, citizens experience new difficulties – traffic congestion, pollution, immigration, overcrowding, and inadequate services.

In our research, we analyze problems and benefits that occur with the growing complexity and offer a new concept considering every city as a live and constantly developing complex adaptive system of many participants and actors that operate in an uncertain environment. These actors (residents, businesses, transport, energy, water supply providers, entertainment, and others) are the main elements of city life.

The new concept of “Smart City 5.0” is based on a previously developed model of Smart City 4.0 (compared with Industry 4.0) and implements the Urban Digital Ecosystem, where every element can be represented by a smart agent operating on its behalf. It is shown that smart services can interact vertically and horizontally in the proposed ecosystem, supporting competition and cooperation behavior based on specialized network protocols for balancing the conflicting interests of different city actors.

The chapter describes the design principles and the general architecture of the Urban Digital Ecosystem, including the basic agent of smart service, protocols of the agent’s negotiation, the architecture, and basic principles Smart City knowledge base.

The developed evolutionary methodology of implementation will ensure a minimum of disruptions to city services during its transformation into an urban ecosystem to harmoniously balance all spheres of life and the contradictory interests of different city actors.

This chapter addresses one aspect of the broad issue of the psychological foundations of the dimensions of multidimensional scaling (MDS) solutions. Using empirical data from three independent studies, it is shown that the dimensionality of MDS solutions is negatively related to individual differences in the level of cognitive differentiation and integrative complexity of individuals and positively related to the individual's ability to discriminate within dimensions. MDS dimensionality is also shown to be affected by a variety of task-related variables such as perceived task difficulty, consistency in providing similarity judgments, confidence, familiarity, and importance attached to the stimuli. The chapter concludes by raising the issue of whether MDS can be validly used to describe complex cognitive processes.

This paper focuses on individuals' improvisation in organizations. The extant literature in this area examines improvisation as either a predictor or an outcome variable. However, there is still considerable confusion about the essence of improvisation and its individual-level determinants. To address these deficiencies, we discuss the differences between improvisation, creativity, and intuition, integrating insights and theories from those fields. Then, we propose a comprehensive model describing a process that includes contextual and individual level variables, which leads to improvisation. Finally, we discuss the theoretical and practical implications of our model and suggest avenues for future research.