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A finite‐difference‐scheme for axisymmetric transient electromagnetic fields is presented, which also takes into account an arbitrary prescribed motion of a substructure and motion inductive effects arising therefrom. For the arrangement at rest transient effects governed by the consequences of electromagnetic induction, e.g. the skin effect, are also taken into account. The behaviour of lumped external network elements is modelled by additional equations. A remeshing procedure is avoided by a special modelling technique. The method is tested for simple arrangements with axial and radial, i.e. expansive motion of a rectangular ring cross‐section. Comparisons with lumped parameter analysis are carried out.

Waste production is one of the most important problems that humankind faces. Human-based activities generate diverse waste types that have to be treated and disposed differently. This results in the need to build more facilities to manage the waste and to avoid further environmental damage. Colombia established a successful policy to close open dumps and to control pollution. Notwithstanding the advances that have been made in final disposal, it is necessary to extend the life of the final disposal sites and increase the closure of open landfills. Valle del Cauca is the third most populated Colombian province, and it is also considered the third province that generates more waste. This chapter addresses the problem of locating solid waste disposal centers in Valle del Cauca by applying the analytic hierarchy process (AHP) with fuzzy logic, a multicriteria method that compares opinions of a decision-making group. Additionally, each potential location area is characterized by considering industrial and environmental issues, societal dynamics, infrastructure and topography, costs, and taxes. After applying a variant of AHP, the decision-making group was able to find that Jamundi is the best location to open the disposal center. The method shows strong potential to identify and prioritize alternative locations for a diverse group of stakeholders. Most importantly, the methodology lets us structure better qualitative and quantitative data, as well as to link multiple levels to avoid choosing locations that will affect society, environment, and other stakeholders, without considering the trade-offs among diverse criteria considering benefits, opportunities, costs, and risks (BOCR).

The purpose of this paper is to describe a systematic investigation of the currents, torques and other electromagnetic quantities in a machine after different short circuits by the means of coupled numerical field and network calculation. The behaviour of a synchronous machine after a stator‐winding fault still is a little known issue. Nevertheless, the occurrence of winding faults can damage the stator winding of the machine severely and may also destroy the whole stator core. Therefore, there exists a strong need for reliable calculation methods for the evaluation of these faults, e.g. the reconstruction of the details of an accident.

The paper discusses an analytical approach which calculates all possible winding connections when absence of nonlinear material behaviour is assumed and nonlinearity is only considered by adjusting the inductances after solving the differential equations. In the following, a more accurate method is given by the numerical field calculation, considering a two‐dimensional time variant permeability distribution on the cross‐section of an electrical machine.

First results of transient time‐stepping calculations of short circuits with special respect on winding currents and radial forces on the rotor are presented.

The approach presented in this paper can be applied in the field of R&D for the dimension of electrical machines and its protection system as well as for the investigation of possible sources of an occurred machine failure.

The bulk of publications that contribute to the topic of inner winding faults are comprised of derivations of analytical models with the assumption of linear material behaviour. The paper puts strong emphasis on the consideration of the nonlinearity.

The purpose of this study is analysis of deformation and vibrations of turbine blades produced by high electrolyte pressure during electrochemical machining.

An experimental setup was designed, experiments were conducted and the obtained results were compared with the finite element results. The deformations were measured according to various flow rates of electrolyte. In finite element calculations, the pressure distribution created by the electrolyte on the blade surface was obtained in the ANSYS® (A finite element analysis software) Fluent software and transferred to the static structural where the deformation analysis was carried out. Three different parameters were examined, namely blade thickness, blade material and electrolyte pressure on blade disk caused by mass flow rate. The deformation results were compared with the gap distances between cathode and anode.

Large deformations were obtained at the free end of the blade and the most curved part of it. The appropriate pressure values for the electrolyte to be used in the production of blisk blades were proposed numerically. It has been determined that high pressure applications are not suitable for gap distance lower than 0.5 mm.

When the literature is examined, it is required that the high speed flow of the electrolyte is desired in order to remove the parts that are separated from the anode from the machining area during electrochemical machining. However, the electrolyte flowing at high speeds causes high pressure in the blisk blades, excessive deformation and vibration of the machined part, and as a result, contact of the anode with the cathode. This study provides important findings for smooth electro chemical machining at high electrolyte flows.

Magnesium alloys are becoming prominent as an alternative to the permanent biomedical implants. In present work, electric discharge drilling (EDD) process has been investigated and optimized for ZM21 Mg alloy that can be used for producing perforated bone implants having geometrically precise micro holes.

Planning of experiments has been carried out in accordance to the Taguchi mixed L18 orthogonal array (OA). The hole overcut (HO), circularity at entrance (Cent) and circularity at exit (Cext) of drilled micro holes were measured as response characteristics during experimentation corresponding to different settings of EDD input parameters. For optimizing multiresponse characteristics, the hybrid approach of grey relational analysis, regression analysis and particle swarm optimization has been implemented.

It is found from hybrid approach that brass electrode along with Ip; 3 Amp, Ton; 50 µs and Toff; 52 µs outperformed over all other parametric settings against the collective result of response characteristics. The experimental values of response characteristics at suggested optimized setting are HO: 93.48 µm; Cent: 0.988 and Cext: 0.992, respectively.

The optimization of EDD process for developing perforated Mg alloy bone implants, using hybrid approach is still missing.

The part of the stator leakage inductance whose quantity changes with the coil pitch is the slot leakage inductance. The purpose of this paper is to determine an analytical expression which accounts for various slot shapes and the coil pitch change. This approach contrasts with the standard one, in which the same characteristics are inaccurately assumed for each slot shape. A further advantage of the proposed analytical expression is that it can also be used to model the slot leakage inductance for different phase numbers.

From the calculated coefficients of a slot by the Finite Element Method (FEM), the characteristics of the slot leakage coefficients are determined by an analytical expression. This helps one to study the connection between the slot shape types and the characteristics of slot leakage coefficients for different phase numbers.

The coefficients, which describe the change of slot leakage, are not the same for every slot type. These inaccuracies can result in deviation from the presented values in the classical literature.

By use of parameters, gained from the FEM calculation of a slot, the characteristics of the slot leakage coefficient can be determined as the function of winding pitch for different phase numbers by an analytical expression. Good accuracy of the analytical method is verified by the determination of the characteristics from the measurement of the two‐, three‐ and six‐phase windings and by the finite element calculations. Beside the speed of the process, it gives an overview about the connection between the slot shape and the coefficients.

Rapid tooling (RT) technique using rapid prototyping (RP) process has been looked upon as an approach which reduces time and cost of production. This study aims to produce electrode for electrical discharge machining (EDM) from acrylonitrile butadiene styrene (ABS) material using the fused deposition modeling (FDM) process of RP. The electrode is coated with copper to a depth of 1 mm by using electroplating to make it conductive. This electrode is termed as RP electrode. The performance of RP electrode having square shape is compared with that of solid electrode of copper having identical size.

In this study, the work piece material is chosen to be titanium Grade-V alloy (Ti-Al6-V4). The input parameters on the EDM machine such as discharge current, pulse on time and voltage are studied, and experiments are designed using the Taguchi method.

The results pertaining to the material removal rate (MRR), electrode wear rate (EWR) and surface roughness (Ra) are reported. It is found that the performance of a coated RP electrode is equally satisfactory when compared with that of a solid electrode.

This paper reports the machining performance of a square-shaped ABS electrode coated with copper. This technique, particularly when the electrode is of intricate shape, saves on cost and time of production of electrode to be used for EDM.

In any machining process, the surface profile of the workpiece is continuously changing with respect to time and input parameters. In a conventional machining process, input parameters are feed and depth of cut whilst other parameters are considered to be constant throughout the process.

The direct and indirect participation of this instantaneous curvature can be used to optimize the strategy of cutting operation in terms of different parameters like heat generation-induced stresses, etc. The concepts of the metric tensor and Riemannian curvature tensor are made use in this study as a representation of curvature itself. The objective of this study is to create a mathematical methodology that can be implemented on a highly flexible machining process to find an optimum cutting strategy for a particular output parameter.

The study also includes different case studies for the validation of this newly introduced mathematical methodology.

The study will also find its position in other mechanical processes like forging and casting where instantaneous curvature affects various mechanical properties.

There is a lack of knowledge transfer regarding administrative challenges and interpersonal experiences of participatory research designs. Aside from the question of whether the research is valid, researchers often have to answer questions regarding the process itself: how did it actually work? The mystery thickens when research and collaborative structures take place beyond and across national and/or cultural borders. Research traditions differ and diverse academic socialisation backgrounds can take a long time to decode. Participatory approaches are still the exception, and in certain research communities they may even be rather exotic. The set-up of collaborative structures and approaches to the field enables or hinders participatory approaches that have proven key in realising inclusive education. This chapter aims to provide thoughts on and insights into the importance, opportunities, and possible pitfalls of planning participatory research across national and cultural borders. It glimpses behind the scenes of mere research procedures to better understand the challenges and explain the opportunities that come with participatory approaches in international contexts.

The purpose of this paper is to serve as an introduction to the theme of this special issue of Health Education on mental health in schools, focusing on work in Germany.

The paper focuses on the conceptual basis of mental health and reflects the meaning of mental health in school settings. The determinants of mental health in young people are mentioned, in particular social inequality. Throughout the paper other authors' contributions to this special issue are mentioned, and shown to have some interesting relationships to one another.

It becomes evident that school can play an important role in the promotion of mental health. What schools can achieve in mental health promotion is then elaborated on with the help of a comprehensive model showing different approaches. Available research evidence shows which interventions are more likely to be successful.

Shortcomings of traditional approaches of school mental health promotion are mentioned and a new perspective (the “good, healthy school”) is outlined.