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The purpose of this paper is to apply the method of separation of variables to obtain the current distribution in the slot of an electrical machine, taking into account the skin effect.

A slot in an electrical machine, filled with a solid conductor, and fed with an externally imposed density current, presents a current distribution that depends on the skin effect. The magnetic potential vector is formulated and solved using a separate representation as a finite sum of unidimensional (space and time) functions, taking into account the boundary conditions. The proposed method obtains the transient and permanent distribution of the current in the interior of the slot, both in transient and steady regime, and the results at the end of the transient are compared with the analytic ones in permanent regime.

The magnetic potential vector in the interior of a slot filled with a solid conductor can be expressed as a finite sum of just 16 modes, which capture the evolution of the field during the transient and permanent regime. These modes are expressed as the product of space and time functions, which have been obtained automatically by the separation of variables algorithm. Instead of solving multiple field problems, one for each time instant, the proposed method just solves two single‐variable differential equations, one in the time domain and other in the spatial one.

The application of the proposed method to non‐sinusoidal currents, such as those generated by variable speed‐drives, would allow to compute the field taking into account both the very small time scale of the pulse width modulation pulses, in the range of kiloHz, and the wide time scale of the currents envelope, in the range of 0‐100 Hz. Extension to 2D and 3D spatial configurations is also under consideration.

Using the method of separation of variables to solve electromagnetic problems provides a new method which can simplify and speed up the computation of transient fields in multidimensional time and space domains.

Ongoing advancements in technology provide the opportunity to build and to improve successful virtual teams. Organizational leaders are facing a dynamic and competitive environment that requires levels of flexibility and fast responses to the global marketplace. The virtual team structure is built on communication that is impacted by the ability of the team members to engage with integrated collaborative technology. Advances in technology enable team members of virtual teams to communicate crucial information and to be perceived as inclusive. Communication technologies have characteristics and capabilities that allow for different levels of communication richness, which refers to the quantity and quality of the shared information provided by the technology. There are two broad categories of collaboration technology: communication-focused technology and coordination-focused technology. Communication-focused technologies are considered key contributors to building trust in virtual teams. Coordination-focused technology refers to a complementary set of tools that can be leveraged to enhance trust and coordination among team members. Advances in technology that are discussed: real-time communications protocols enhances video calls through any type of device including wearable technology; Internet of Things making it easier and more natural for people to interact with the objects to stay connected; higher video resolution continues to improve in terms of price, quality, and performance, which will increase the number and type of devices for communication.

The purpose of this paper is to investigate the factors that may impact on the acceptance of the e-book amongst mathematics and statistics (MAS) students at higher education institutions in Libya.

A theoretical model has been developed based on the technology acceptance model (TAM). The factors divided into three groups: intrinsic variables represent the first group of factors that are related to the user or the potential users itself, such as Self-Efficacy and Resistance to Change. Second, extrinsic variables include all the factors that reflect the characteristics of the e-book and the infrastructure for universities, which are Mobility (M), Facilities (F) and Library Service Quality (LS). TAM constructs from Perceived Ease Of Use (PEOU), Perceived Usefulness (PU), Attitude (AU) and Behaviour Intention (BI) represent the last group. Data relating to the constructs were collected through a self-administered survey in 2014. The developed model was measured and tested by structural equation modelling using AMOS (22.0).

The result confirmed that the structural model fits the data well. According to the results, TAM constructs have a significant impact on the acceptance of e-book among MAS students at universities in Libya. In addition, the intrinsic variables play the important role to predict students’ BI. Although the extrinsic variables were less important, Facilities was the strong factor in this group.

The adoption of e-book amongst higher education students in Libya is still quite low. Hence, identifying the factors that may contribute to e-book adoption is crucial. The contribution of this paper is to determine the factors that effect on the acceptance of e-book amongst MAS students at higher education institutions in Libya.

This study is intended to work out a bottleneck in the comprehension of the relational nexus which links the set of key strategic resources (SRs) of a company, represented by the uncertain recognition and the ambiguous clustering of their intangible components. The purpose of this paper is to provide a candidate solution for a rational appraisal of the inventory of the knowledge-based resources held by a company, which synergically form its Intellectual Capital (IC).

This goal is achieved by the means of a qualitative/quantitative approach composed of sequential phases, intended to: atomize the value domain of the firm into its basic building blocks; gauge their mutual interactions and impacts; re-aggregate those involved entities accordingly; cluster them into a collection of identified and validated Intangible Assets (IAs). Never giving any direct judgment on the IAs themselves (whose extension can be fuzzy or unknown). But on the impacts between the value drivers they are built on.

The proposed procedure, step-by-step illustrated by means of a numerical simulation, out of the amorphous mass of the SRs, returns an analytic picture of its composing elements keeping track of their intertwined connections and mutual influence. Consequently, allowing the comprehension of the actual framing and of the relational positioning and magnitude of such entities.

This risk-mitigated rational identification of IAs allows the analyst to target a proper evaluation technique on them. And the management of the company to mindfully allocate/leverage on them to improve business performance and strategy alignment. The implementation returns some analytic tools which render a diagnostic snapshot of the composing elements of the IC, increasing the awareness of such entities and allowing internal/external benchmarking.

The suggested methodology mitigates the risk of discretionality in the definition of the perimeter of each target-entity, by avoiding any direct biased judgment on them. So that each asset gets unambiguously identified within a network-logic and the interlinked portfolio of knowledge-based resources can be assessed and managed in an rational and traceable way.

This study aims to provide an overview of the state-of-the-art in efficiency measurement within higher education (HE). Specifically, it seeks to gather all relevant articles on the topic and subsequently categorize these studies using a flowchart based on two core aspects of the topic.

This study employs bibliometric and content analyses to conduct a systematic literature review. The Preferred Reporting Items for Systematic Review (PRISMA) framework is used to identify the search protocol, followed by analyses to classify and categorize articles.

The bibliometric analysis identifies prominent themes, methodologies and literature gaps. The content findings highlight key insights on higher educational institution (HEI) efficiency, including organizational structures, services and operational activities.

This research contributes to the existing knowledge by synthesizing global literature on HEI’s efficiency. Utilizing the flowchart developed by the authors, the study captures the state-of-the-art based on two critical aspects: methodologies and content. Insights from the analysis and subsequent classification of previous literature provide valuable directions for future research.

Rectangular conductors play an important role in planar transmission line structures, multiconductor transmission lines, in power transmission and distribution systems, LCL filters, transformers, industrial busbars, MEMs devices, among many others. The precise determination of the inductance of such conductors is necessary for their design and optimization, but no explicit solution for the AC resistance and internal inductances per-unit length of a linear conductor with a rectangular cross-section has been found, so numerical methods must be used. The purpose of this paper is to introduce the use of a novel numerical technique, the proper generalized decomposition (PGD), for the calculation of DC and AC internal inductances of rectangular conductors.

The PGD approach is used to obtain numerically the internal inductance of a conductor with circular cross-section and with rectangular cross-section, both under DC and AC conditions, using a separated representation of the magnetic vector potential in a 2D domain. The results are compared with the analytical and approximate expressions available in the technical literature, with an excellent concordance.

The PGD uses simple one-dimensional meshes, one per dimension, so the use of computational resources is very low, and the simulation speed is very high. Besides, the application of the PGD to conductors with rectangular cross-section is particularly advantageous, because rectangular shapes can be represented with a very few number of independent terms, which makes the code very simple and compact. Finally, a key advantage of the PGD is that some parameters of the numerical model can be considered as additional dimensions. In this paper, the frequency has been considered as an additional dimension, and the internal inductance of a rectangular conductor has been computed for the whole range of frequencies desired using a single numerical simulation.

The proposed approach may be applied to the optimization of electrical conductors used in power systems, to solve EMC problems, to the evaluation of partial inductances of wires, etc. Nevertheless, it cannot be applied, as presented in this work, to 3D complex shapes, as, for example, an arrangement of layers of helically stranded wires.

The PGD is a promising new numerical procedure that has been applied successfully in different fields. In this paper, this novel technique is applied to find the DC and AC internal inductance of a conductor with rectangular cross-section, using very dense and large one-dimensional meshes. The proposed method requires very limited memory resources, is very fast, can be programmed using a very simple code, and gives the value of the AC inductance for a complete range of frequencies in a single simulation. The proposed approach can be extended to arbitrary conductor shapes and complex multiconductor lines to further exploit the advantages of the PGD.

The purpose of this paper is to solve non‐linear parametric thermal models defined in degenerated geometries, such as plate and shell geometries.

The work presented in this paper is based in a combination of the proper generalized decomposition (PGD) that proceeds to a separated representation of the involved fields and advanced non‐linear solvers. A particular emphasis is put on the asymptotic numerical method.

The authors demonstrate that this approach is valid for computing the solution of challenging thermal models and parametric models.

This is the first time that PGD is combined with advanced non‐linear solvers in the context of non‐linear transient parametric thermal models.

The purpose of this paper is to focus on the advanced solution of the parametric non-linear model related to the Rayleigh-Benard laminar flow involved in the modeling of natural thermal convection. This flow is fully determined by the dimensionless Prandtl and Rayleigh numbers. Thus, if one could precompute (off-line) the model solution for any possible choice of these two parameters the analysis of many possible scenarios could be performed on-line and in real time.

In this paper both parameters are introduced as model extra-coordinates, and then the resulting multidimensional problem solved thanks to the space-parameters separated representation involved in the proper generalized decomposition (PGD) that allows circumventing the curse of dimensionality. Thus the parametric solution will be available fast and easily.

Such parametric solution could be viewed as a sort of abacus, but despite its inherent interest such calculation is at present unaffordable for nowadays computing availabilities because one must solve too many problems and of course store all the solutions related to each choice of both parameters.

Parametric solution of coupled models by using the PGD. Model reduction of complex coupled flow models. Analysis of Rayleigh-Bernard flows involving nanofluids.