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Hysteresis is one of the main concepts used in Layard, Nickell and Jackman′s book, Unemployment: Macroeconomic Performance and the Labour Market. Attempts to clarify the concept of hysteresis, from its formal representation to its empirical applications. Emphasizes the idea that hysteresis refers back to a given set of formal properties, independently of the phenomenologies within which it is liable to be encountered. In economics, the fields concerned may indeed vary a lot (labour market, foreign trade, etc.). By highlighting all the formal properties of hysteresis, shows how the assimilation of phenomena characterized by a zero eigenvalue for linear systems (or unit‐root systems for discrete‐time processes) is wrong and, moreover, how the imprecise use of the concepts can lead to the particular constraints affecting unit‐root econometrics being overlooked.

The purpose of this paper is to investigate the hysteresis hypothesis for the price and quantity of Brazilian imports in recent years.

The empirical measure of strong macro hysteresis, as developed by Piscitelli et al., was incorporated into import demand and pass‐through panel cointegration equations.

The results show that the number of sectors that do not reject hysteresis is larger for the import price than for the demand for imported goods. The evidence supports Dixit's idea that the presence of hysteresis should diminish the degree of pass‐through. Correcting for hysteresis makes quantity and price of imports more sensitive to exchange rate variations.

This paper contributes to the literature by introducing Piscitelli et al.'s measure to test the hysteresis hypothesis in import prices and quantity.

The purpose of this paper is to estimate the effect of policy and exchange rate uncertainty shocks on EU countries’ exports to the world economy. The authors examine the performance of the four biggest economies, namely Germany, France, Italy and the UK, under policy and exchange rate uncertainty in exports to some of the most important global export destinations (the USA, Japan, Brazil, Russia and China).

For this purpose, the authors apply a non-linear model, where suddenly strong spurts of exports occur when changes of the exchange rate go beyond a zone of inaction, which the authors call “play” area – analogous to mechanical play. The authors implement an algorithm describing path-dependent play hysteresis into a regression framework. The hysteretic impact of real exchange rates on exports is estimated based on the period from 1995M1 to 2015M12.

Looking at some of the main export destinations of the selected EU member countries, the USA, Japan and some of the members of BRICS (Brazil, Russia and China), the authors identify significant hysteretic effects for a large part of the EU member countries’ exports. The authors find that their export activity is characterized by “bands of inaction” with respect to changes in the real exchange. To check for robustness, the authors estimate export equations for limited samples: excluding the recent financial crisis and excluding the period up to the burst of the dotcom bubble and September 11. In addition, the authors employ an economic policy uncertainty variable and an exchange rate uncertainty variable as determinants of the width of the area of weak reaction of exports.

Overall, the authors find that those specifications which take uncertainty into account display the highest goodness of fit, with economic policy uncertainty dominating exchange rate uncertainty. In other words, the option value of waiting dominates the real exchange rate effect on the EU member countries’ exports.

The existence of “bands of inaction” (called “play”) in EU member countries’ exports should lead to a more objective discussion of peaks and troughs in those countries’ real exchange rates and, more specifically, of the relevance of internal and external devaluation and other indicators to gain international competitiveness on exports in political debates. If policy and/or exchange rate uncertainty are diminished, one may expect an earlier boost in exports, if the home currency is devaluing in real terms.

The results are useful as arguments in the debate about exchange rate pain threshold vs export triggers.

The authors focus on the export performance of the four biggest economies in the European Union, namely Germany, France, Italy and the UK. The authors examine their respective export performance, as an innovation, under policy and exchange rate uncertainty and, for this purpose, look at some of the most important global export destinations (the USA, Japan and the BRICS (Brazil, Russia and China)). The authors do so, also as an innovation, by differentiating between intervals of weak and strong reaction of their exports to real exchange rate changes.

Widely used in micro‐position devices and vibration control, the piezoelectric actuator exhibits strong hysteresis effects, which can cause inaccuracy and oscillations, even lead to instability. If the hysteretic effects can be predicted, a controller can be designed to correct for these effects. This paper aims to present a neural network hysteresis model with an improved Preisach model to predict the output of piezoelectric actuator.

The improved Preisach model is given: A wiping‐out memory sequence is defined that is along a single axis only and at the same time the ascending and the descending extreme points are separated. The extended area variable is calculated according to wiping‐out memory sequence. The relationship between the two inputs (the extended area variable and variable rate of input signal) and the hysteresis output is implemented with a neural network to approximate the hysteresis model for the piezoelectric actuators.

Some experiments are carried out with a piezoelectric ceramic (PST150/7/40 VS12) and the results show the neural network hysteresis model can reliably predict the hysteretic behaviours in piezoelectric actuators.

The improved Preisach model is a simple model that is implemented by a neural network to reliably predict the hysteretic output in piezoelectric actuators.

The main aim of the present work is to examine the effects of trailing edge strip (TES) on the wake region of a plunging airfoil that oscillates prior and beyond the static stall angle of attack.

In this study, experimental investigations were carried out to explore the wake characteristics of a plunging Eppler 361airfoil equipped with TES flap. The experiments involved measurements of flapped and unflapped airfoil wake velocity for the range of initial AOA (0 and 12°). Surface pressure measurements as a supplementary data were also carried out. Data were taken at reduced frequencies of 0.03 and 0.073 and different distances downstream from trailing edge.

The results showed the hysteresis between the plunging wake in the upstroke and down-stroke motion. When the airfoil oscillated beyond the static stall angle of attack, huge variations on the wake profiles were found because of the interaction between LEV and Von Kármán vortices. More velocity defect in the wake region was realized by adding the TES but this effect was not the same for different phases of oscillation cycle. Also the power spectra of dominant frequencies and the extension of wake vortices were significantly increased by fitting the TES on the plunging airfoil.

The knowledge of the present study is necessary to enhance the performance of wind turbines, rotorcraft blades and maneuvering aircraft.

To date, no investigation has been conducted to determine the effects of a TES on the plunging airfoil aerodynamics.

The purpose of this paper is to provide a comprehensive analysis of different material models when observing the magnetisation dynamics and power losses in non-oriented soft magnetic steel sheets (SMSSs).

During the analysis four different magnetic material models were used for describing the static material characteristics, which characterised the materials’ magnetisation behaviour with increasing accuracies: linear material model, piecewise linear material model, non-linear H(B) characteristic and the static hysteresis material model proposed by Tellinen. The described material models were implemented within a parametric magneto-dynamic model (PMD) of SMSSs, where the dynamic responses as well as power loss calculations from the obtained models were analysed.

The momentous influences of various levels of detail on the calculation of dynamic variables and power losses inside SMSS with non-uniform magnetic fields were elaborated, where various static material characteristic models were evaluated, ranging from linear to hysteretic constitutive relationships.

The resulting PMD model using different static models was analysed over a frequency range from quasi-static to f=1,000 Hz for different levels of magnetic flux density up to B _max=1.5 T.

The presented analysis provides fundamental insight when calculating dynamic electromagnetic variables and power losses inside non-linear SMSSs, which is instrumental when selecting an adequate model for a specific application.

This paper provides closer insight on the way non-linearity, magnetic saturation and hysteresis affect the energy loss and magnetisation dynamics in SMSSs through the level of detail in the used material model. The strongly coupled model addresses both induced eddy currents and the ferromagnetic materials’ magnetisation behaviour simultaneously using varying levels of detail so that the interplay between skin effect (i.e. eddy currents) across laminations and hysteresis can be resolved accurately. Therewith, adequate models for specific applications can be selected.

The purpose of this article is to investigate the magnetic properties and the hysteresis loops behavior of a ferrimagnetic cubic nanowire with mixed spins S_A = 3/2 and S_B = 2.

We have used the Monte Carlo simulation to examine the influences of the exchange interaction J_B, the crystal field ∆ and the temperature on the magnetic properties and hysteresis loops of the nanowire. More exactly, we have shown the temperature dependence of the sublattice magnetizations (m_A and m_B) and the total magnetization (M) for several values of the Hamiltonian parameters, as well as the corresponding phase diagrams. Finally, the effect of an external magnetic field is studied by plotting the hysteresis loops of the system for different values of exchange interaction, crystal field and temperature.

The obtained results show the existence of second-order phase transitions, as well as the compensation behavior. Moreover, according to the values of the Hamiltonian parameters, the system can exhibit one, two or three hysteresis loops.

The magnetic nanowires are of great interest in experimental works, but without theoretical explanations, the experimental results cannot be clarified in depth. For this, we contribute through this theoretical study to understand the nanowires, especially those with mixed spins (2, 3/2).

This paper proposes a robust modeling method of a giant magnetostrictive actuator which has a rate‐dependent nonlinear property.

It is known in statistics that the Least Wilcoxon learning method developed using Wilcoxon norm is robust against outliers. Thus, it is used in the paper to determine the consequence parameters of the fuzzy rules to reduce the sensitiveness to the outliers in the input‐output data. The proposed method partitions the input space adaptively according to the distribution of samples and the partition is irrelative to the dimension of the input data set.

The proposed modeling method can effectively construct a unique dynamic model that describes the rate‐dependent hysteresis in a given frequency range with respect to different single‐frequency and multi‐frequency input signals no matter whether there exist outliers in the training set or not. Simulation results demonstrate that the proposed method is effective and insensitive against the outliers.

The main contributions of this paper are: first, an intelligent modeling method is proposed to deal with the rate‐dependent hysteresis presented in the giant magnetostrictive actuator and the modeling precision can fulfill the requirement of engineering, such as the online modeling issue in the active vibration control; and second, the proposed method can handle the outliers in the input‐output data effectively.

Owing to the excellent performance, giant magnetostrictive materials (GMMs) are widely used in many engineering fields. The dynamic Jiles–Atherton (J-A) model, derived from physical mechanism, is often used to describe the hysteresis characteristics of GMM. However, this model, despite cited by many different literature studies, seems not to possess unique expressions, which may cause great trouble to the subsequent application. This paper aims to provide the rational expressions of the dynamic J-A model and propose a numerical computation scheme to obtain the model results with high accuracy and fast speed.

This paper analyzes different published papers and provides a reasonable form of the dynamic J-A model based on functional properties and physical explanations. Then, a numerical computation scheme, combining the Newton method and the explicit Adams method, is designed to solve the modified model. In addition, the error source and transmission path of the numerical solution are investigated, and the influence of model parameters on the calculation error is explored. Finally, some attempts are made to study the influence of numerical scheme parameters on the accuracy and time of the computation process. Subsequently, an optimization procedure is proposed.

A rational form of the dynamic J-A model is concluded in this paper. Using the proposed numerical calculation scheme, the maximum calculation error, while computing the modified model, can remain below 2 A/m under different model parameter combinations, and the computation time is always less than 0.5 s. After optimization, the calculation speed can be enhanced with the computation accuracy guaranteed.

To the best of the authors’ knowledge, this paper is the first one trying to provide a rational form of the dynamic J-A model among different citations. No other research studies focus on designing a detailed computation scheme targeting the fast and accurate calculation of this model as well. And the performance of the proposed calculation method is validated in different conditions.