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The primary purpose of this descriptive study was to compare the levels of, and relationships among mental health problems, mental health shame, self-compassion, work engagement and work motivation between workers in Japan (collectivistic and success-driven culture) and the Netherlands (individualistic and quality-oriented culture).

A cross-sectional design, where convenience samples of 165 Japanese and 160 Dutch workers completed self-report measures about mental health problems, shame, self-compassion, engagement and motivation, was used. Welch t-tests, correlation and regression analyses were conducted to compare (1) the levels of these variables, (2) relationships among these variables and (3) predictors of mental health problems, between the two groups.

Dutch workers had higher levels of mental health problems, work engagement and intrinsic motivation, and lower levels of shame and amotivation than Japanese workers. Mental health problems were associated with shame in both samples. Mental health problems were negatively predicted by self-compassion in Japanese, and by work engagement in Dutch employees.

The novelty of this study relates to exploring differences in work mental health between those two culturally contrasting countries. Our findings highlight potential cultural differences such as survey responding (Japanese acquiescent responding vs Dutch self-enhancement) and cultural emphases (Japanese shame vs Dutch quality of life). Job crafting, mindfulness and enhancing ikigai (meaningfulness in life) may be helpful to protect mental health in these workers, relating to self-compassion and work engagement. Findings from this study would be particularly useful to employers, managers and staff in human resources who work with cross-cultural workforce.

In a modular transformer with a wounded amorphous core, the authors should make some cutting to limit the eddy currents in its magnetic ribbon. The purpose of this paper is to deal with 3D magnetic field analysis, including the eddy currents induced by varying frequency of power. The influence of the core leg cutting on the power losses values, in the three variants of a one-phase modular transformer structure, has been presented.

3D field problems including eddy currents of various frequency were analysed using the electrodynamic potentials and V within the finite element method. The wave method and iterative one of the laminated core homogenization, have been employed. The values of the calculated losses have been verified experimentally.

The reduction of the core losses by axial cutting of the transformer legs is an efficient approach for the loss limitation. The wave method is not acceptable for homogenization of the amorphous core for its operation above 1 kHz. The iterative method is the better way to perform the homogenization.

Due to very thin (less than 50 μm) amorphous ribbon, the unhomogenization of the laminated magnetic core should be performed. Thus, the solid core with equivalent parameters has been assumed for the computer simulations. For the frequencies above 1 kHz, the iterative method should be used to determine the equivalent electrical conductivity of the solid substitute core.

Using the wave method with the electrodynamic similarity laws and assuming the wave penetration depth, the equivalent electrical conductivity of the homogenized core, has been determined. This approach is valid for supply frequencies below 1 kHz. For the higher frequencies the authors had to use the iterative method. It seems to be valid for another cores with amorphous and nanocrystalic ribbons. For the modular amorphous core it is only way to calculate the losses in the solid geometry of the homogenized laminated magnetic circuit.

The purpose of this paper is to examine the calculation of magnetic field distribution in the modular amorphous transformers under short‐circuit state including the flux by the voltage supplying. The magnetically asymmetrical transformer (amorphous asymmetrical transformer – AAT) has been compared also with the symmetrical one (amorphous symmetrical transformer – AST).

3D field problems were analyzed with total ψ and reduced ϕ potentials within the finite element method (FEM). The calculated fluxes have been verified experimentally.

The field method which includes voltage excitation is helpful for flux density (B) calculation and winding reactances determination, as well. Calculations and tests yield similar flux distributions in both AST and AAT constructions. One should emphasize that AAT is better for manufacturing and repairing.

Owing to very thin (80 μm) amorphous ribbon, the solid core has been assumed for computer simulations.

Employment of a field method for calculation of the innovative three‐phase amorphous modular transformers. New construction of amorphous transformer, i.e. AAT, has been manufactured at Opole University of Technology.

The purpose of this paper is to find new non-traveling wave solutions and study its localized structure of Caudrey-Dodd-Gibbon-Kotera-Sawada (CDGKS) equation.

The authors apply the Lie group method twice and combine with the Exp-function method and Riccati equation mapping method to the (2+1)-dimensional CDGKS equation.

The authors have obtained some new non-traveling wave solutions with two arbitrary functions of time variable.

As non-linear evolution equations is characterized by rich dynamical behavior, the authors just found some of them and others still to be found.

These results may help the authors to investigate some new localized structure and the interaction of waves in high-dimensional models. The new non-traveling wave solutions with two arbitrary functions of time variable are obtained for CDGKS equation using Lie group approach twice and combining with the Exp-function method and Riccati equation mapping method by the aid of Maple.

Although numerous national and organisational level approaches have taken to improve their mental health, Japanese workers still suffer from high rates of mental health problems. Despite its worldwide application, neuro-linguistic programming (NLP) has not been evaluated for these problems in-depth. The purpose of this paper is to examine the effects of NLP training for mental health among Japanese workers.

A pre-post test design with repeated measurements was used with 30 Japanese workers, who were undertaking NLP Practitioner Certification training. The effects on mental health were assessed with the Depression, Anxiety and Stress Scale-21 and the Warwick-Edinburgh Mental Well-being Scale at pre-training, post-training and a three-month follow-up.

The mean scores of depression and stress decreased significantly, and mental well-being increased significantly between pre-training and post-training and between pre-training and follow-up. There was no significant difference between post-training and the follow-up for any of the measures.

The results suggest this training was effective for mental health of Japanese workers, and the positive effects on mental well-being were sustained.

This is the first ever study to empirically evaluate the effects of the regulated NLP training on the mental health of Japanese workers, conducted by researchers well-versed in NLP. This training might be conducive to improving the mental health of the Japanese workforce. Larger scale and/or controlled studies are needed.

The purpose of this paper is to develop the method of taking the eddy current losses in the laminated magnetic circuits into account during implicit transient calculations. The nonlinear magnetization characteristic of iron and the hysteresis losses can also be considered in the simulations done with the developed method.

The paper presents complex equivalent magnetic permeability derived from the presumed angular frequency in a laminated magnetic circuit. On this basis, the synthesis of a magnetic permeability as a function of the Laplace variable “s” is presented. After transformation of the variable “s” to a variable “z” of the Z transformation, it is possible to conduct discrete time calculation of transient states of magnetic circuits including the eddy current losses. An iterative process is developed to take the saturation of the magnetic circuit in these calculations into account. As regards hysteresis losses, the scalar model of magnetic hysteresis by Juhani Tellinen was implemented. The new method is validated by calculations of a two-coil transformer.

It is important to take into account the losses in sheet metal directly in the implicit transient calculations. This possibility is provided by the presented method based on the synthesis of the equivalent magnetic permeability μ^(s). The presented method was proved to be correct and efficient. The calculated sheet metal losses were compared with the results presented in literature. Good conformance of results was attained.

The method enables calculation of eddy current and hysteresis losses in laminated magnetic circuits during calculations of transient states. It does not need, unlike the previous methods, previously provided information (“a priori”) about the content of higher harmonics in waveforms. The method takes into account mutual dependence of transient waveforms of currents in the analysed system and losses of laminated magnetic circuit, expressed by eddy currents and hysteresis losses. Its implementation comes down to using in calculations a filter of the IIR type and corresponds to its calculation complexity. The author plans to use the presented method in the finite elements method transient calculations.

A new approach is a synthesis of the equivalent magnetic permeability in Laplace domain, which creates an equivalent RC circuit for permeability. Analytic equations for parameters of this equivalent circuit are original. A method for considering nonlinear magnetization characteristic and hysteresis losses was presented. In calculations of transient states of systems with magnetic circuits, one can use the developed equivalent circuit of magnetic permeability in a form of the IIR filter. Operator magnetic permeability includes fractional derivative of Laplace’s variable “vs”. Therefore, the equivalent IIR filter includes “history” of the processes that take place in the laminated magnetic circuit to the current, calculated time moment. This “history” in terms of its content is limited only by the degree of the applied IIR filter. It enables to calculate “step by step”, without previous (“a priori”) knowledge about harmonic components of the whole waveforms. It was necessary in the previously used methods, when determining parameters of magnetic permeability. The method proposed in the paper allows for calculations with taking into account direct dependence of an electric part of the system on its magnetic part.

The purpose of this paper is to calculate and measure transients for two different constructions of electrodynamic accelerators (ironless and iron-core) supplied by a three-section power system (three capacitor banks). The optimization of power supply parameters (switch-on times and capacitances of individual sections) in terms of system efficiency has been carried out.

Calculations have been carried out using a field-circuit model. For three-dimensional magnetostatic analysis, the Maxwell software and finite element method (FEM) were used, while for circuit model, the Matlab/Simulink software was implemented. For optimization of the supply system parameters, the genetic algorithm was used. The mathematical models were verified experimentally by using the original laboratory stand.

The efficiency of the system is much higher in case of iron-core accelerator. In both cases, the results obtained for optimized supply settings are only slightly better than those obtained by simultaneously switching on the thyristors and for symmetrical capacity division.

Due to the presented field-circuit model, eddy currents in rails have been neglected. In the field model, there was no possibility to combine current flow calculations with moving of the projectile.

Using the presented filed-circuit model, both electrical and mechanical transients could be calculated with sufficient precision. Thus, it could be used in the optimization of supply system. The solution time is low compared with the solution time of the transient field model.

This paper aims to develop a methodology for progressive finite element (FE) modeling of transformers, from simple to complex models of both magnetic cores and windings.

The progressive modeling of transformers is performed via a subproblem (SP) FE method. A complete problem is split into SPs with different adapted overlapping meshes. Model refinements are performed from ideal to real flux tubes, one-dimensional to two-dimensional to three-dimensional models, linear to nonlinear materials, perfect to real materials, single wire to volume conductor windings and homogenized to fine models of cores and coils, with any coupling of these changes.

The proposed unified procedure efficiently feeds each SP via interface conditions (ICs), which lightens mesh-to-mesh sources transfers and quantifies the gain given by each refinement on both local fields and global quantities, with a clear view on its significance to justify its usefulness, if any. It can also help in education with a progressive understanding of the various aspects of transformer designs.

Models of different accuracy levels are sequenced with successive additive corrections supported by different adapted meshes. The way the sources act at each correction step, up to the full models with their actual geometries, is given a particular care and generalized, allowing the proposed unified procedure. For all the considered corrections, the sources are always of IC type, thus only needed in layers of FE along boundaries, which lightens the required mesh-to-mesh projections between subproblems.

The purpose of this paper is to create a reliable nonlinear magnetic equivalent circuit (NMEC) of the hybrid magnetic bearing (HMB). Commonly used magnetic equivalent circuits of HMB omit a saturation effect of the magnetic material as well as the leakage and fringing flux. It results in imprecise modelling of the magnetic field distribution. On the other hand, only 3D finite element analysis (FEA) can be used to precisely simulate the magnetic field in this type of the magnetic bearing. The proposed NMEC incorporates the saturation effect of the magnetic material, as well as the leakage and fringing flux.

The magnetic equivalent circuit of presented HMB is proposed to obtain a reliable model that ensures short calculation time. Developed NMEC incorporates the phenomena as the saturation effect, as well as the leakage and fringing flux. The reluctance of the air gap that includes the fringing flux was calculated using 3D FEA. Kirchhoffs’ laws were used to create a set of nonlinear equations that were iteratively solved by Broyden’s method.

Incorporating into NMEC of the HMB a saturation effect of the magnetic material, as well as the leakage and fringing flux, resulted in the accurate model that was in good agreement with 3 D finite element model and the real object. The developed NMEC offers the calculation time in the range of miliseconds, therefore can be successfully used in the engineering design instead of the FEM.

Presented NMEC can be considered as a fundamental model that can be successfully used for accurate and fast simulation of the HMB. Proposed NMEC includes considerable factors that decide about the model accuracy such as the saturation effect of the ferromagnetic material and the leakage and fringing flux. The developed NMEC can be used in the optimization procedures and for simulations of dynamic responses.

The purpose of this paper is to elaborate the effective method of adaptation of the external penalty function to the genetic algorithm.

In the case of solving the optimization tasks with constraints using the external penalty function, the penalty term has a larger value than the primary objective function. The sigmoidal transformation is introduced to solve this problem. A new method of determining the value of the penalty coefficient in subsequent iterations associated with the changing penalty has been proposed. The proposed approach has been applied to the optimization of an electromagnetic linear actuator, and the mathematical model of the devices contains equations of the magnetic field, by taking into account the nonlinearity of ferromagnetic material.

The proposed new approach of the penalty function method consists in the reduction of the external penalty function in successive penalty iterations instead of its increase as it is in the classical method. In addition, the method of normalization of constraints during the formulation of optimization problem has a significant impact on the obtained results of optimization calculations.

The proposed approach can be applied to solve constrained optimization tasks in designing of electromagnetic devices.