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The purpose of this paper is to propose a new method for computing validities in the multimodel approach.

The multimodel approach offers an interesting alternative and a powerful tool to bypass the difficulties to model, control and diagnose a nonlinear and complex system. Its idea is defined as the apprehension of a nonlinear behaviour of a system by a set of local models characterizing the system operation in different operating zones. In spite of the success of its application in different fields, many problems related to the synthesis of multimodel approach remain open. These include, in particular, the method of obtaining the contribution degrees, also called validities, of the base-models for the deduction of the multimodel output.

The presented method may lead to superior results in comparison with the residue approach commonly used in the calculation of validities. Numerical simulation results and an experimental validation on a semi-batch reactor clearly illustrated the effectiveness of the proposed method and proved its impact on the improvement of the performances of the multimodel approach. Moreover, the multimodel approach using the new validities’ computation method can lead to perfect modelling of the process.

The proposed method discussed in the paper has the potential to make the multimodel approach more efficient in the modelling of complex real systems.

A significant contribution of the paper is the formulation of a new constrained optimization problem that can be solved by using a powerful mathematical tool such as the active set method, allowing to estimate the validity indexes in the multimodel approach. The obtained optimal solution can lead to perfect modelling of nonlinear and complex real systems.

Addresses the standardization of the measurements and the labels for concepts commonly used in the study of work organizations. As a reference handbook and research tool, seeks to improve measurement in the study of work organizations and to facilitate the teaching of introductory courses in this subject. Focuses solely on work organizations, that is, social systems in which members work for money. Defines measurement and distinguishes four levels: nominal, ordinal, interval and ratio. Selects specific measures on the basis of quality, diversity, simplicity and availability and evaluates each measure for its validity and reliability. Employs a set of 38 concepts ‐ ranging from “absenteeism” to “turnover” as the handbook’s frame of reference. Concludes by reviewing organizational measurement over the past 30 years and recommending future measurement reseach.

The purpose of this paper is to present a new concept based on a neural network validity approach in the area of multimodel for complex systems.

The multimodel approach was recently developed in order to solve the modeling problems and the control of complex systems. The strategy of this approach coincides with the usual approach of the engineer which consists in subdividing a complex problem to a set of simple, manageable sub‐problems that can be solved separately. However, this approach still faces some problems in design, especially in determining models and in finding the appropriate method of calculating validities.

A novel approach based on neural network validity shows very remarkable performances in multimodel for complex systems.

The validity of each model is based on the convergence of each neural network. For a fast convergence the proposed approach can be online to give a good performance in multimodel representation for system with rapid dynamics.

The proposed concept discussed in the paper has the potential to be applied to complex systems.

The suggested approach is implemented and reviewed with a complex dynamic and fast process compared to the residue approach commonly used in the calculation of validities. The results prove to be satisfactory and show a good accuracy.

This paper aims to describe the simulation technique which can be used at the design stage in order to efficiently develop low‐electromagnetic emission type lighting implements.

The influence on the conducted noise by the change of the implements' shape is investigated employing the 3D finite element method. Because of the difficulty in modelizing the electronic ballast accurately as a noise source, the electronic ballast is replaced by a comparison spectrum transmitter. Line impedance stabilization network is used for the measurement of the noise. The validity of this numerical model is confirmed by comparing the measurement results.

The validity of the computation was confirmed by comparison with the measured results of a simplified implement model. The difference between the measured and calculated results was less than 5 dB all over the frequency range.

The frequency range is from 10 to 30 MHz and the construction and wiring of the implement have a great influence on the electromagnetic field.

In previous papers, circuit simulators are used to analyze conducted emission from an electronic circuit including inverter, where common mode current cannot be taken into consideration. Therefore, the displacement current was taken into consideration in the model. Not only the implement, but also the measurement method and environment are modelized in the analyzed model.

The purpose of this paper is to propose a new electromagnetic spherical actuator with three‐degree‐of‐freedom. Multi‐degree‐of‐freedom actuators which can be operated in arbitrary axis come to attract attention because of the solution for efficiency, weight, size, and so on. Particularly, spherical actuators are studied as the application to the joints and eyeballs for robots because they can be freely rotated in every axis direction.

The paper proposes a new electromagnetic spherical actuator with three‐degree‐of‐freedom in rotation, and the torque characteristics of the actuator are computed by the 3D finite element method (FEM). The validity of the computation is confirmed through the measurement of a prototype.

It is found that this actuator realized the high torque of more than 1.0 Nm in every axis circumference.

A new spherical three‐degree‐of‐freedom actuator is proposed. The torque characteristics of the improved model are calculated employing the 3D FEM. The validity of the analysis is verified through the comparison with the measured results of the prototype. Furthermore, the improved model is proposed to increase the torque, and the effectiveness of the model is confirmed.

The current study aimed to develop and validate a scale to model factors affecting digital technology access for instructional use. The scale was mainly used to assess the structural model. Besides, tests of difference were addressed regarding digital technology access for instructional use based on gender, teaching experience and school location.

The authors implemented a survey design in this study. A scale based on prior studies was developed, validated and piloted. The pilot study data were computed for an exploratory factor analysis. Further, partial least squares structural equation modeling (PLS-SEM) and t-test procedures were used for the main data analysis (n.2677). The authors also included the importance-performance map analysis to extend of the results of the PLS-SEM.

The findings of the study successfully assessed the validity and reliability of the scale. All hypothetical relationships in the structural model were positively significant. The t-test results show that teaching experience and school location were significantly different regarding instructional use access; however, an insignificant difference emerged based on gender.

Failure in technology integration is possible if policies have not been carefully prepared. Therefore, users' perception is an essential factor in determining technology integration, including access to digital technology.

This research has the potential to enhance the understanding of access to digital technology in the context of developing countries by the elaboration of the proposed model's instrument development and validation, path analysis assessment and difference test examination with a large sample size. Also, the current study emphasizes the importance of raising awareness about digital technology access that the model can facilitate a valid and reliable foundation for future researchers interested in conducting similar types of research.

The purpose of this paper is to develop a dynamic analysis method of a novel spherical resonant actuator. In this method, the magnetic field equation is coupled with the electric circuit equation and the motion equation with the mesh modification method using the Laplace equation applied to the rotation of the spherical actuator.

The static torque characteristics and dynamic characteristics of the spherical resonant actuator using the proposed method are clarified. The calculated results are compared with the measured ones.

The calculated static torque agrees well with the measured one. The validity of the computation using the proposed method is quantitatively clarified through the comparison with the measurement.

The paper proposes the dynamic analysis method of the complicated spherical resonant actuator using the mesh modification method by the Laplace equation.

The purpose of this paper is to investigate the lateral forces during the fall of a magnet in a conducting pipe, when the direction of magnetization of the magnet is fixed. If the direction of magnetization is not parallel to the axis of the pipe, lateral forces occur and a decentration of the magnet happens.

The problem is studied numerically, with a T − h 3D FE formulation well‐suited for the problem. Computational results are compared with experimental results.

The physical model is given and the main force coefficients analyzed. The lateral forces and the decentration phenomenon are studied as a function of the main parameters (thickness and radius of the pipe).

The direction of magnetization is a key parameter to analyze the dynamics of a magnet motion inside a conducting pipe, when the radii of the pipe and the magnet are not so close. This analysis with a fixed direction of magnetization allows one to quantify the lateral forces and the decentration, and is a first step to understand the complete motion which includes the rotation which can be linked to the decentration.

This study aims to overcome the involved challenging issues and provide high-precision eigensolutions. General eigenproblems in the system of ordinary differential equations (ODEs) serve as mathematical models for vector Sturm-Liouville (SL) and free vibration problems. High-precision eigenvalue and eigenfunction solutions are crucial bases for the reliable dynamic analysis of structures. However, solutions that meet the error tolerances specified are difficult to obtain for issues such as coefficients of variable matrices, coincident and adjacent approximate eigenvalues, continuous orders of eigenpairs and varying boundary conditions.

This study presents an h-version adaptive finite element method based on the superconvergent patch recovery displacement method for eigenproblems in system of second-order ODEs. The high-order shape function interpolation technique is further introduced to acquire superconvergent solution of eigenfunction, and superconvergent solution of eigenvalue is obtained by computing the Rayleigh quotient. Superconvergent solution of eigenfunction is used to estimate the error of finite element solution in the energy norm. The mesh is then, subdivided to generate an improved mesh, based on the error.

Representative eigenproblems examples, containing typical vector SL and free vibration of beams problems involved the aforementioned challenging issues, are selected to evaluate the accuracy and reliability of the proposed method. Non-uniform refined meshes are established to suit eigenfunctions change, and numerical solutions satisfy the pre-specified error tolerance.

The proposed combination of methodologies described in the paper, leads to a powerful h-version mesh refinement algorithm for eigenproblems in system of second-order ODEs, that can be extended to other classes of applications in damage detection of multiple cracks in structures based on the high-precision eigensolutions.

The paper aims to contribute to the discussion on Shari'ah governance systems by examining the extent of disclosure on the Shari'ah Supervisory Board (SSB) as well as the content of the Board's report in the annual reports of 23 Islamic banks in Malaysia and Indonesia. The paper also investigates the disclosures about zakat (Islamic levy).

The study is a cross-sectional analysis of annual report disclosures in the year 2009. The paper uses both disclosure indices and content analysis to measure the extent of disclosures about SSB and zakat. The paper also tests hypotheses examining the relationship between SSB characteristics and the extent of the SSB-related and zakat disclosures.

The results indicate that SSB-related and zakat disclosures are still limited, with only four banks disclosing more than half of the SSB Index. What is noticeable is the low level of disclosure on sensitive matters. Among the factors associated with SSB-related disclosures are cross-membership with other SSBs and the expertise of SSB members in accounting, banking, economics or finance

Originality/value

The study is the first to provide an in-depth analysis of Shari'ah disclosures in Malaysian and Indonesian Islamic banks. As such, this study makes an important contribution to the debate on Shari'ah governance systems and has implications for regulators and standard setters. The Malaysian and Indonesian standard setters could play an important role in ascertaining appropriate disclosure requirements relating to the SSB as the study suggests that the level of disclosure is less than expected. The evidence also suggests the need for mandatory enforcement of standards on these types of disclosures.