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This paper aims to present the approximation of lightning currents waveshapes by the multi-peaked analytically extended function (MP-AEF) for the experimentally measured channel-base currents in the artificially triggered lightning discharges. Modified transmission line model of lightning return strokes having the channel current both linearly decaying and sinusoidally changing with height (MTLSIN) is used to calculate the lightning electromagnetic field.

MP-AEF’s parameters for the artificially triggered lightning channel-base currents are calculated by using Marquardt least squares method (MLSM). Lightning electromagnetic fields are calculated based on electromagnetic theory relations, thin-wire antenna model of the vertical lightning channel and the assumption of the perfectly conducting ground. MTLSIN model as an engineering model of lightning strokes is used to obtain the electric field results as these are simultaneously measured in rocket-triggered lightning experiments together with the channel-base currents.

MP-AEF approximates multi-peaked pulse waveshapes. Some important function parameters are chosen prior to the approximation procedure, such as current peaks and the corresponding time moments of those peaks, which presents an advantage in comparison to other functions. The desired accuracy of approximation is obtained by choosing an adequate number of function terms. MLSM is used for the estimation of unknown parameters. Using MTLSIN model, the influence of the channel height and return stroke speed on the lightning electromagnetic field waveshape is analyzed in this paper.

MP-AEF may be used for approximation of various multi-peaked waveshapes. It has no errors in the points of maxima which is important for the lightning protection systems design. MTLSIN model may be validated by using simultaneously measured lightning electromagnetic fields at various distances from the channel and for channel heights estimated in the experiments. It is also possible to approximate measured current derivatives by MP-AEF and use them for further computation.

MTLSIN model is proposed in this paper for the evaluation of lightning electromagnetic fields induced by artificially triggered lightning discharges. The procedure is based on the approximation of lightning channel-base currents by the multi-peaked analytically extended function previously proposed by the authors. This function may be used not only for representing lightning currents but also for other waveshapes as current derivatives, electric and magnetic fields and their derivatives, which are all important for the lightning protection design. MTLSIN gives lightning electromagnetic fields results which are in better agreement with measured fields than those obtained by other models from literature.

Drawing on configuration theory and adopting a holistic perspective, the authors aim to explore strategic supply chain elements' interaction with internal and external contextual conditions. Specifically, they evaluate multivariate co-alignment of supply chain's capabilities (agility, adaptability, alignment), adhocracy organizational structure and environmental uncertainty (dynamism, munificence and complexity) that lead to superior performance outcomes (supply chain cycle time, financial performance, market performance).

A survey research design is adopted to collect primary and secondary data from 182 international firms. Cluster analysis and profile deviation techniques are employed first to derive a taxonomy of strategic supply chains and then examine multivariate co-alignment.

The analysis reveals that four groups of triple-A supply chains could emerge. It is found that strategic supply chains exhibit a flexible/organic/fluid organizational structure and a high level of triple-As in their processes. These supply chains perform superior to a higher level of environmental complexity, munificence and dynamism.

This study's results provide insights for practitioners by informing their investment decisions for developing strategic supply chains. Specifically, this research highlights the contextuality of triple-A supply chains and offers best practices to capitalize on strategic supply chains.

Executives in organizations require a holistic understanding of various elements to ensure that the organizational system as a whole performs effectively. This research offers insights into the interdependencies of triple-A supply chains with other organizational and external environmental elements. Noteworthy implications for scholarship in operations/supply chain management and supply chain practitioners are presented.