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The main purpose of the paper is to develop model basing on the modified and properly‐adopted Fermi‐Dirac equation which combines proper accuracy with adequate simplicity as well as to show how steady state and transient curves resulting from this model can be applied for solving design task.

The standard Fermi‐Dirac equation was modified and extended. Full performance cycle for the SMA actuator was characterized by double‐valued function describing the actuator activation and the actuator deactivation. All these functions and parameters can be easily determined by analysis of measurement data or with use of Hooke‐Jeeves optimization algorithm.

SMA linear actuator can be used in mechatronic systems as a special non‐standard drive when ultra‐light mass and very simple mechanical construction of power feed system is required. The proposed steady‐state and transient performance curves as well as operation diagram constitute sufficient base for effective designing SMA drive systems.

The greatest disadvantage of a SMA actuator is long time of deactivation resulting from slow self‐cooling process. As far as efficiency is concerned as essential factor for choosing the most suitable linear actuator, there is no sense to take into account a linear SMA actuator because of its very low efficiency.

Designer can use performance curve which determines proper length of SMA actuator and range of its motion. The proposed model can be implemented in SMA drive control unit for controlling position of the actuator.

Similarities between change of martensitic phase during transition process and probability P of electron energy level distribution described by the Fermi‐Dirac two‐variable equation were taken into account. Such an approach seems to express in the most suitable way the physical nature of m‐a transition. The authors decided to extend concept (proposed in Jayender et al.) and to adopt the Fermi‐Dirac equation for describing behaviour of a SMA linear actuator.

Examines the seventeenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

This paper aims to provide an introduction to smart materials, with an emphasis on their capabilities and applications.

Following an introduction, this paper first considers what smart materials are and what they can do. It then discusses existing and emerging applications of shape changing, self-actuating, self-healing, self-diagnostic and self-sensing materials.

Although difficult to define unambiguously, smart materials offer a range of unique characteristics and have been used in a multitude of products, ranging from household goods and novelty items to automotive components and medical devices. They are the topic of extensive research and all manner of new applications will emerge in the future, reflecting both technological developments and a growing awareness of their capabilities.

This paper provides an insight into the rapidly developing technology and applications of smart materials.

The purpose of this study is to discover and model the asymmetry in the price volatility of financial markets, in particular the foreign exchange markets as the first underlying applications.

The volatility of the financial market price is usually defined with the standard deviation or variance of the price or price returns. This standard definition of volatility is split into the upper part and the lower one, which are termed here as Yang volatility and Yin volatility. However, the definition of yin‐yang volatility depends on the scale of the time, thus the notion of scale space of price‐time is also introduced.

It turns out that the duality of yin‐yang volatility expresses not only the asymmetry of price volatility, but also the information about the trend. The yin‐yang volatilities in the scale space of price‐time provide a complete representation of the information about the multi‐level trends and asymmetric volatilities. Such a representation is useful for designing strategies in market risk management and technical trading. A trading robot (a complete automated trading system) was developed using yin‐yang volatility, its performance is shown to be non‐trivial. The notion and model of yin‐yang volatility has opened up new possibilities to rewrite the option pricing formulas, the GARCH models, as well as to develop new comprehensive models for foreign exchange markets.

The asymmetry of price volatility and the magnitude of volatility in the scale space of price‐time has yet to be united in a more coherent model.

The new model of yin‐yang volatility and scale space of price‐time provides a new theoretical structure for financial market risk. It is likely to enable a new generation of core technologies for market risk management and technical trading strategies.

This work is original. The new notion and model of yin‐yang volatility in scale space of price‐time has cracked up the core structure of the financial market risk. It is likely to open up new possibilities such as: a new portfolio theory with a new objective function to minimize the sum of the absolute yin‐volatilities of the asset returns, a new option pricing theory using yin‐yang volatility to replace the symmetric volatility, a new GARCH model aiming to model the dynamics of yin‐yang volatility instead of the symmetric volatility, new technical trading strategies as are shown in the paper.

This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to modify the upstream shock–boundary layer interaction (SBLI) around an A320 morphing prototype to control these instabilities, with emphasis to the attenuation or even suppression of the transonic buffet. The modification of the aerodynamic performances according to a large parametric study carried out at Reynolds number of 4.5 × 10⁶, Mach number of 0.78 and various angles of attack in the range of (0, 2.4)° according to two morphing concepts (travelling waves and trailing edge vibration) are discussed, and the final benefits in aerodynamic performance increase are evaluated.

This article examines through high fidelity (Hi-Fi) numerical simulation the effects of the trailing edge (TE) actuation and of travelling waves along a specific area of the suction side starting from practically the most downstream position of the shock wave motion according to the buffet and extending up to nearly the TE. The present paper studies through spectral analysis the coherent structures development in the near wake and the comparison of the aerodynamic forces to the non-actuated case. Thus, the physical mechanisms of the morphing leading to the increase of the lift-to-drag ratio and the drag and noise sources reduction are identified.

This study investigates the influence of shear-layer and near-wake vortices on the SBLI around an A320 aerofoil and attenuation of the related instabilities thanks to novel morphing: travelling waves generated along the suction side and trailing-edge vibration. A drag reduction of 14% and a lift-to-drag increase in the order of 8% are obtained. The morphing has shown a lift increase in the range of (1.8, 2.5)% for angle of attack of 1.8° and 2.4°, where a significant lift increase of 7.7% is obtained for the angle of incidence of 0° with a drag reduction of 3.66% yielding an aerodynamic efficiency of 11.8%.

This paper presents results of morphing A320 aerofoil, with a chord of 70cm and subjected to two actuation kinds, original in the state of the art at M = 0.78 and Re = 4.5 million. These Hi-Fi simulations are rather rare; a majority of existing ones concern smaller dimensions. This study showed for the first time a modified buffet mode, displaying periodic high-lift “plateaus” interspersed by shorter lift-decrease intervals. Through trailing-edge vibration, this pattern is modified towards a sinusoidal-like buffet, with a considerable amplitude decrease. Lock-in of buffet frequency to the actuation is obtained, leading to this amplitude reduction and a drastic aerodynamic performance increase.

Digital twin (DT) is an emerging technology that enables sophisticated interaction between physical objects and their virtual replicas. Although DT has recently gained significant attraction in both industry and academia, there is no systematic understanding of DT from its development history to its different concepts and applications in disparate disciplines. The majority of DT literature focuses on the conceptual development of DT frameworks for a specific implementation area. Hence, this paper provides a state-of-the-art review of DT history, different definitions and models, and six types of key enabling technologies. The review also provides a comprehensive survey of DT applications from two perspectives: (1) applications in four product-lifecycle phases, i.e. product design, manufacturing, operation and maintenance, and recycling and (2) applications in four categorized engineering fields, including aerospace engineering, tunneling and underground engineering, wind engineering and Internet of things (IoT) applications. DT frameworks, characteristic components, key technologies and specific applications are extracted for each DT category in this paper. A comprehensive survey of the DT references reveals the following findings: (1) The majority of existing DT models only involve one-way data transfer from physical entities to virtual models and (2) There is a lack of consideration of the environmental coupling, which results in the inaccurate representation of the virtual components in existing DT models. Thus, this paper highlights the role of environmental factor in DT enabling technologies and in categorized engineering applications. In addition, the review discusses the key challenges and provides future work for constructing DTs of complex engineering systems.

A new model for the power system, covering resistance, self‐inductance, mutual inductance, and capacitive coupling between planes is presented. The model parameters are calculated from the geometry of the actual board. No measurements are necessary to set up a model for a new board. The model has been verified against detailed computer simulations and measured data.

This paper aims to explore the relevant literature available regarding the use of repetitive transcranial magnetic stimulation (rTMS) as a mode of treatment for obsessive-compulsive disorder (OCD); to evaluate the evidence to support the use of rTMS as a treatment option for OCD.

The authors electronically conducted data search in five research databases (MEDLINE, CINAHL, Psych INFO, SCOPUS and EMBASE) using all identified keywords and index terms across all the databases to identify empirical studies and randomized controlled trials. The authors included articles published with randomized control designs, which aimed at the treatment of OCD with rTMS. Only full-text published articles written in English were reviewed. Review articles on treatment for conditions other than OCD were excluded. The Covidence software was used to manage and streamline the review.

Despite the inconsistencies in the published literature, the application of rTMS over the supplementary motor area and the orbitofrontal cortex has proven to be promising in efficacy and tolerability compared with other target regions such as the prefrontal cortex for the treatment of OCD. Despite the diversity in terms of the outcomes and clinical variability of the studies under review, rTMS appears to be a promising treatment intervention for OCD.

The authors of this scoping review acknowledge several limitations. First, the search strategy considered only studies published in English and the results are up to date as the last day of the electronic data search of December 10, 2020. Though every effort was made to identify all relevant studies for the purposes of this review per the eligibility criteria, the authors still may have missed some relevant studies, especially those published in other languages.

This review brought to bare the varying literature on the application of rTMS and what is considered gaps in the knowledge in this area in an attempt to evaluate and provide information on the potential therapeutic effects of rTMS for OCD.

In this chapter, we consider the complexity of issues associated with violence in schools and provide an overview of this 33rd volume of Advances in Learning and Behavioral Disabilities. We begin with a brief consideration of the nature and definitions of violence as it manifests in schools and then consider three broad areas addressed by the chapters in this volume. First, we consider bullying and the bullying dynamic, including cyberbullying, and the intersection of bullying and students with disabilities. Next, we address the extraordinarily difficult topic of school shootings, including whether and how we can predict, prevent, and respond to school shootings. Finally, we consider more broadly advances in building a more positive school climate and sense of community and creating safer schools generally. In all of these, we acknowledge the challenges of understanding the complexity and multiple causes of school violence, and the apparent rise in many forms of violence in schools, but conclude with thoughts on the positive avenues identified by authors in this volume for ways we might better support children and youth in both preventing violence and responding to it in appropriate, supportive ways.