Sources and effects of Foreign Language Enjoyment, Anxiety and Boredom: A Structural Equation Modelling Approach

The present study is among the first to investigate how three foreign language (FL) emotions (enjoyment (FLE), anxiety (FLCA) and boredom (FLB)) are related to each other. It is the first study to consider how the three FL emotions are shaped by one learner-internal variable (attitude towards the FL), by two perceived teacher behaviours (frequency of use of the FL in class and unpredictability) and how all these variables affect FL achievement. Participants were 332 learners from all over the world studying a wide variety of FLs who filled out an online questionnaire. A close-fitting structural equation model revealed associations between FLE, FLCA, and FLB. Teacher behaviours positively affected FLE, with no discernible effect on FLB or FLCA. Only FLCA was found to have a (negative) effect on academic achievement. The study confirms the complex relationship between teacher behaviours and positive emotions in the FL classroom.

Modeling of Memristors under Periodic Signals of Different Parameters

In this paper, the problem of modeling memristors is studied. Two types of memristors with carbon and tungsten doping fabricated by the Knowm Inc. are tested. The memristors have been examined with either sinusoidal or triangle voltage wave periodic excitation. Some different frequencies, amplitudes and signal shapes have been applied. The collected data have been averaged and subjected to high frequency filtering. The quality of measurement data has also been discussed. The averaged measurement has been modeled using three popular memristor models: Strukov, Biolek and VTEAM. Some additional feathers to the considered models have been proposed and tested. Memristor is usually modeled by a set of algebraic-differential equations which link both electrical values (i.e., voltage and current) and the internal variable(s) responsible for the element dynamics. The interior-point with box constrains optimization method has been used to obtain the optimal parameters of the memristor model that fit best to the collected data. The results of the optimization process have been discussed and compared. The sensitivity to the different frequency range has been also examined and reviewed. Some conclusions and future work ideas have been postulated.

The area rule for circulation in three-dimensional turbulence

An important idea underlying a plausible dynamical theory of circulation in three-dimensional turbulence is the so-called area rule, according to which the probability density function (PDF) of the circulation around closed loops depends only on the minimal area of the loop, not its shape. We assess the robustness of the area rule, for both planar and nonplanar loops, using high-resolution data from direct numerical simulations. For planar loops, the circulation moments for rectangular shapes match those for the square with only small differences, these differences being larger when the aspect ratio is farther from unity and when the moment order increases. The differences do not exceed about 5% for any condition examined here. The aspect ratio dependence observed for the second-order moment is indistinguishable from results for the Gaussian random field (GRF) with the same two-point correlation function (for which the results are order-independent by construction). When normalized by the SD of the PDF, the aspect ratio dependence is even smaller ( < 2%) but does not vanish unlike for the GRF. We obtain circulation statistics around minimal area loops in three dimensions and compare them to those of a planar loop circumscribing equivalent areas, and we find that circulation statistics match in the two cases only when normalized by an internal variable such as the SD. This work highlights the hitherto unknown connection between minimal surfaces and turbulence.

Complete solvability of the inertial spin model with an averaged spin

We study the inertial spin model which consists of two variables: velocity as a mechanical observable and spin as an internal variable. In this paper, we slightly modified the original inertial spin model where the spin in the dynamics of the velocity is replaced by the average of spins. Moreover, by introducing two external control functions (rotation control and alignment control), we show the emergence of velocity and spin alignments mainly depends on these control functions. Finally, we perform numerical simulations that support and complement our theoretical results.

A Bivariate Volterra Series Model for the Design of Power Amplifier Digital Predistorters

The operation of the power amplifier (PA) in wireless transmitters presents a trade-off between linearity and power efficiency, being more efficient when the device exhibits the highest nonlinearity. Its modeling and linearization performance depend on the quality of the underlying Volterra models that are characterized by the presence of relevant terms amongst the enormous amount of regressors that these models generate. The presence of PA mechanisms that generate an internal state variable motivates the adoption of a bivariate Volterra series perspective with the aim of enhancing modeling capabilities through the inclussion of beneficial terms. In this paper, the conventional Volterra-based models are enhanced by the addition of terms, including cross products of the input signal and the new internal variable. The bivariate versions of the general full Volterra (FV) model and one of its pruned versions, referred to as the circuit-knowledge based Volterra (CKV) model, are derived by considering the signal envelope as the internal variable and applying the proposed methodology to the univariate models. A comparative assessment of the bivariate models versus their conventional counterparts is experimentally performed for the modeling of two PAs driven by a 30 MHz 5G New Radio signal: a class AB PA and a class J PA. The results for the digital predistortion of the class AB PA under a direct learning architecture reveal the benefits in linearization performance produced by the bivariate CKV model structure compared to that of the univariate CKV model.

STABILITY CONSIDERATIONS FOR ELASTIC-PLASTIC PROCESSES WITH DAMAGE

Classical theory of plasticity is fairly complete with flow rules, convexity of yield surfaces, extremum principles, and the uniqueness theorem. For the strain-hardening plasticity, Drucker’s postulates are established and proven based on the plastic-work and energy principles. Plasticity models have been further applied to heterogeneous and cementitious materials with certain degrees of success. In this paper, the stability statements of strain-hardening and strain-softening processes in concrete are examined by utilizing thermodynamic potential functions in the stress space and by applying Euler’s theorem of homogenous functions. It is shown that by specifying a strain-hardening parameter to account for the plastic strains and a damage parameter to represent the effect of microcracking, the dissipation inequality can be used to establish the Drucker’s stability postulate for the plastic flow within the framework of the internal variable theory of thermodynamics. Using the same approach and assuming uncoupling between plastic flow and microcracking, the formation leads to a softening stability statement for damage processes in concrete.

Effect of Organizational Commitment, Compensation and Job Satisfaction on Employee Performance Through Organizational Citizenship Behavior In Bank BPD DIY Employees Senopati Branch Office

This study aims to determine the factors that affect the performance at the BANK BPD DIY Senopati branch office. The method in this research is accidental sampling. The analytical method used is the classical assumption test, t-test and Sobel test. Based on the research results, it is known that commitment has a significant positive effect on OCB, compensation has a significant effect on OCB, and satisfaction does not affect OCB, while commitment has a significant effect on employee performance, compensation has a significant positive effect on performance, job satisfaction has no effect on performance. OCB has a positive effect on employee performance. commitment has a significant positive effect on performance with the OCB variable as an intervening variable, compensation has a significant effect on performance with OCB as an internal variable has no significant effect on performance through OCB As an intervening variable and job satisfaction It is expected that this research can be used to measure commitment, compensation, and employee satisfaction as well as OCB on employee performance behavior

Hydrodynamic limit of a coupled Cucker–Smale system with strong and weak internal variable relaxation

In this paper, we present the hydrodynamic limit of a multiscale system describing the dynamics of two populations of agents with alignment interactions and the effect of an internal variable. It consists of a kinetic equation coupled with an Euler-type equation inspired by the thermomechanical Cucker–Smale (TCS) model. We propose a novel drag force for the fluid-particle interaction reminiscent of Stokes’ law. While the macroscopic species is regarded as a self-organized background fluid that affects the kinetic species, the latter is assumed sparse and does not affect the macroscopic dynamics. We propose two hyperbolic scalings, in terms of a strong and weak relaxation regime of the internal variable towards the background population. Under each regime, we prove the rigorous hydrodynamic limit towards a coupled system composed of two Euler-type equations. Inertial effects of momentum and internal variable in the kinetic species disappear for strong relaxation, whereas a nontrivial dynamics for the internal variable appears for weak relaxation. Our analysis covers both the case of Lipschitz and weakly singular influence functions.

The configurations of HRM bundles in MNCs by their contributions to subsidiaries’ performance and cultural dimensions

The main goal of the paper is to determine whether the HQs of MNCs evaluate the significances of particular HRM subfunctions to their foreign subsidiaries’ performance differently depending on a specific cultural context and—as a consequence—various configurations of HRM subfunctions may be identified in different cultural contexts. The theoretical assumptions are based on a combination of the configurational and contextual perspectives through a cross-cultural lens. In the empirical research an abductive reasoning process is applied. The research sample covers 200 headquarters of MNCs. To analyze the collected data both descriptive and correlational statistical methods are used. Two patterns of configurational bundle of HRM have been identified: A and B. Pattern A tends to be more system oriented and Pattern B more centralization oriented. Pattern A covers the subsidiaries which, with comparison to their HQ, are of lower power distance, higher individualism, higher masculinity, lower uncertainty avoidance, longer time orientation, and higher indulgence. Pattern B is composed of the subsidiaries with the opposite signs of the cultural distance index. The originality of the study consists in the application of the abductive research model. Thanks to it, we were able to search and find the simplest and most probable explanations for our observations. And the value of the research itself lies in the evidence that the contextual perspective with its configurational implications in the HRM research field is useful in identifying the phenomena that are difficult to identify or unidentifiable otherwise. The findings of the present study provide some knowledge on how cultural distance (external variable) and the significance of HRM to the subsidiary’s performance results (internal variable) interact in impacting on different configurational bundles of HRM subfunctions, their centralization practices and knowledge flows in MNCs.