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This paper aims to discuss various numerical implementations of the integral equation in the hybrid finite element method‐Dirichlet boundary condition iteration (FEM‐DBCI) method for the numerical solution of unbounded static and quasi‐static electromagnetic field problems.

Three numerical implementations are described and compared from the point of view of accuracy and complexity, by means of two examples regarding simple electrostatic problems.

The implementation by means of a pair of integration surfaces made of element sides leads to accuracy levels which are much better than that of a single surface (made of element sides) and only a little worse than that of a single surface connecting point in the middle of finite element sides.

The former implementations, however, are simpler since they are practically the same as that of a standard boundary element method integral equation.

The paper constitutes a useful guide to the implementation of the FEM‐DBCI method.

This paper aims to propose a hybrid method, called finite element method‐Dirichlet boundary condition iteration (FEM‐DBCI), for the computation of time‐harmonic eddy current problems inside a conductor heated by coils in 3D open‐boundary geometry.

The method assumes the electrical field as unknown on a mesh of tetrahedral edge elements. The heating power density inside the conductor is then computed and a steady‐state thermal analysis is performed on the same mesh of nodal tetrahedra to calculate the temperature distribution inside the heated piece, taking radiation and convection into account. A numerical example is also provided.

The method couples a differential equation for the interior problem in terms of the electric fields with an integral equation for the exterior one. The global algebraic system is efficiently solved in an iterative way.

The paper illustrates the computation of time‐harmonic eddy current problems inside a conductor heated by coils.

In this paper, the optimization of the shape of the magnetic channel inside a superconducting cyclotron is performed. The objective is to ensure a proper shaping and reduction of the intensity of the cyclotron magnetic field so as to facilitate the extraction of the charged particles. The optimization problem is solved by following two different approaches: a genetic algorithm and a simulated annealing approach. The relative advantages of each of the methods employed for the optimization of the magnetic channel are discussed.

Charge iteration is an iterative procedure for the finite element computation of unbounded electrical fields, created by voltaged conductors. It makes use of a fictitious boundary, enclosing all the conductors, on which the electrical potential is first guessed and then iteratively improved according to the charge lying on the conductor surfaces. Highlights the theoretical foundations of the procedure outside any numerical context. From this useful insight, obtains a model which can aid the user in utilization of the numerical version of the procedure.

This paper reviews and classifies research connecting supply chain risk management (SCRM) and information technology (IT) and derives a structured proposal for fruitful research directions.

The authors conducted a systematic literature review of the interplay of SCRM and IT, drawing from major journals in the relevant fields. These findings are enriched by experiences from a three-year international research project.

Current research focuses on the role of IT for risk reduction, rather than for risk identification, analysis and monitoring. While much research has investigated operational supply chain risk, fewer insights into disruption risk are available. There is little research on the role of IT in SCRM beyond its potential to enhance information sharing among supply chain partners. To address these gaps, the paper proposes a two-dimensional framework to categorize IT potential for SCRM according to the source and impact of disruption risk on physical supply chain flows, which suggests promising directions for future research.

The paper offers a systematic review to further our understanding of the relationship of SCRM and IT. In addition, it presents and discusses nine areas for further research aimed at mitigating the gaps identified at the intersection of SCRM and IT.

The concept of robustness in manufacturing is not easy to capture and even harder to quantify. This paper elaborates an approach to assess robustness in production systems from a holistic input-throughput-output perspective using a pragmatic robustness indicator.

First, in order to have a precise understanding of what needs to be measured, a concept of robustness in production systems is defined based on a literature overview. Three different aspects are considered to be essential to comprehensively describe robustness in production: the deviations of input resources, of performance and of output. These aspects are translated into an aggregated indicator based on developments of production costs, order delays and output volumes. The indicator-based assessment approach is eventually applied to a flow-shop scheduling case study in the chipboard industry.

The study shows that an assessment of robustness should not solely focus on a single aspect of a production system. Instead, a holistic view is required addressing the tradeoffs that robustness must balance, such as the one between the realized performance, the corresponding resource requirements and the resulting output. Furthermore, the study emphasizes that robustness can be interpreted as a superior system capability that builds upon flexibility, agility, resilience and resistance.

First, the paper is a call to further test and validate the proposed approach in industry case studies. Second, the paper suggests a modified understanding of robustness in production systems in which not only the deviation of one single variable is of interest but also the behavior of the whole system.

The approach allows practitioners to pragmatically evaluate a production system’s robustness level while quickly identifying drivers, barriers and tradeoffs.

Compared to existing assessment approaches the proposed methodology is one of the first that evaluates robustness in production systems from a holistic input-throughput-output perspective highlighting the different tradeoffs that have to be balanced. It is based upon a comprehensive concept of robustness which also links robustness to adjacent capabilities that were otherwise only treated separately.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

The purpose of this paper is to compare the hybrid FEM-BEM and FEM-DBCI methods for the solution of open-boundary static and quasi-static electromagnetic field problems.

After a brief review of the two methods (both coupling a differential equation for the interior problem with an integral equation for the exterior one), they are compared in terms of accuracy, memory and computing time requirements by means of a set of simple examples.

The comparison suggests that FEM-BEM is more accurate than FEM-DBCI but requires more computing time.

Then FEM-DBCI appears more appropriate for applications which require a shorter computing time, for example in the stochastic optimization of electromagnetic devices. Conversely, FEM-BEM is more appropriate in cases in which a high level of precision is required in a single computation.

Note that the FEM-BEM considered in this paper is a non standard one in which the nodes of the normal derivative on the truncation boundary are placed in positions different from those of the potential.

The optimization of the cross section of an axisymmetric induction heating device is performed by means of genetic algorithms (GAs).

The hybrid finite element method–Dirichlet boundary condition iteration method is used to deal with the unbounded nature of the field. The formulation of the electromagnetic problems takes into account skin and proximity effects in the source currents.

The convergence of GAs towards the optimum is very fast, since less than a thousand analyses have been necessary.

A special derivation of the finite element global system is presented which allows us to save computing time.