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The purpose of this paper is to deal with the failure analysis of a fractured spar stiffener, extruded from 7075-T6 aluminum alloy, which was found in the central wing, trailing edge structure of a military transport aircraft. The previous loading history and the dominant environmental factors (corrosive and humid atmosphere, water entrapment, etc.) suggest corrosion and fatigue as the principal failure modes, synergistically acting on the wing component.

This study presents the failure analysis concentrated on finding evidence of failure mechanisms and plausible root-cause(s) of the fractured spar stiffener. Chemical analysis, stereo and scanning electron microscopy, as well as finite element analysis employed as the main analytical tools for material characterization and failure investigation.

The overall evaluation of the findings suggest that the failure caused by a synergy of two mechanisms; a crack initiated in the longitudinal, extrusion direction by an environmentally assisted corrosion attack, then propagated by the superimposed transverse stress field, branched/deflected due to a low crack driving force and extended in a transverse path through a high cycle fatigue process. Finally, the complete fracture occurred as fast fracture, resulted by a ductile overload.

This paper deals with an industrial damage case study, providing analysis and modeling from structural engineering standpoint. The aforementioned findings concerning the fractured aircraft component allow gaining a deeper knowledge about the mechanisms of crack initiation and propagation which, in turn, can produce a valuable feedback to design, inspection and maintenance procedures. This includes a modified heat treatment from T6 to T73 temper for the redesigned component.

The aim of this chapter is to explore the economic impact of the ICT sector in the Greek economy. In the first stage of this study, the ICT sector is identified as a composite agglomerate of various manufacturing and service industrial sectors of the economy, following its international definition introduced by OECD. Under this concept, we explore the main structural indicators of its business activity and quantify its impact in the Greek economy (in terms of production value, GDP, investment, and employment), utilizing the basic principles of Input-Output analysis. We further investigate the ICT sector’s linkages with other industries as a ‘route’ for technology and innovation diffusion in the Greek production system by approximating the ICT sector as the enabling force for the digital transformation of production in the face of Industry 4.0. The empirical results of this analysis are accompanied by a review of some key qualitative characteristics of the sector and elaborate on major challenges and relevant policy implications that arise.

This study aims to explore how the local tour guides (LTGs) operate through the sharing economy platform. This study explores how LTGs have responded to the COVID-19 pandemic restrictions using self-efficacy and other resources to improve resilience and performance. This study also delineates the working mechanisms of peer-to-peer (P2P) platform-enabled, dynamic capability building processes, in the tourism sharing economy.

This research adopted an interpretive approach to understand the focal phenomenon using two types of data. A total of 40 semi-structured interviews with LTGs and 26,478 online tourist reviews from tour guide service participants’ before and during the COVID-19 pandemic were used.

The findings of this study revealed that LTGs used sharing economy platforms to arrange flexible tour guide services. Resilience emerged through dynamic capability that addressed contextual factors in real time. LTGs coordinated different resources and customers during a time of uncertainty. Different sources of self-efficacy and types of dynamic capability were identified. The interplay between LTGs’ self-efficacy and dynamic capability was also delineated.

The findings provide guidance for LTGs on P2P platforms and other sharing economy sectors on how diverse resources enabled by the sharing economy can enhance resilience during times of uncertainty. LTGs that engage with contextual information and are dynamic can adopt itineraries and services that will benefit tourists and their business.

This study contributes to the sharing economy literature by theorizing the working flow that enables LTGs to exert self-efficacy and leverage dynamic capability on P2P platforms. This study also contributes by linking resilience to contextual factors in real time. The outcomes provide guidance for LTGs to remain competitive and establish resilience in uncertain environments.