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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 present study deals with the numerical modeling of the low-velocity impact damage of laminated composites which have increasingly important applications in aerospace primary structures. Such damage, generated by various sources during ground handling, substantially reduces the mechanical residual performance and the safe-service life. The purpose of this paper is to present and validate a computationally efficient approach in order to explore the effect of critical parameters on the impact damage characteristics.

Numerical modeling is considered as one of the most efficient tool as compared to the expensive and time-consuming experimental testing. In this paper, a finite element model based on explicit dynamics formulations is adopted. Hashin criterion is applied to predict the intralaminar damage initiation and evolution. The numerical analysis is performed using the ABAQUS® programme.

The employed modeling approach is validated using corresponding numerical data found in the literature and the presented results show a reasonable correlation to the available literature data. It is demonstrated that the current model can be used to capture the force-time response as well as damage parameter maps showing the intralaminar damage evolution for different impact cases with respect to the physical boundary conditions and a range of impact energies.

Low-velocity impact damage of laminated composites is still not well understood due to the complexity and non-linearity of the damage zone. The presented model is used to predict the force-time response which is considered as one of the most important parameters influencing the structural integrity. Furthermore, it is used for capturing the damage shape evolution, exhibiting a high degree of capability as a damage assessment computational tool.

This study aims to identify variability in aviation operators in order to gain greater understanding of the changes in aviation professional groups. Research has commonly addressed human factors and automation in broad categories according to a group’s function (e.g., pilots, air traffic controllers [ATCOs], engineers). Accordingly, pilots and Air Traffic Controls (ATCOs) have been treated as homogeneous groups with a set of characteristics. Currently, critical themes of human performance in light of systems’ developments place the emphasis on quality training for improved situational awareness (SA), decision-making and cognitive load.

As key solutions centre on the increased understanding and preparedness of operators through quality training, the authors deploy an iterative mixed methodology to reveal generational changes of pilots and ATCOs. In total, 46 participants were included in the qualitative instrument and 70 in the quantitative one. Preceding their triangulation, the qualitative data were analysed using NVivo and the quantitative analysis was aided through descriptive statistics.

The results show that there is a generational gap between old and new generations of operators. Although positive views on advanced systems are being expressed, concerns about cognitive capabilities in the new systems, training and skills gaps, workload and role implications are presented.

The practical implications of this study extend to different profiles of operators that collaborate either directly or indirectly and that are critical to aviation safety. Specific implications are targeted on automation complacency, bias and managing information load, and training aspects where quality training can be aided by better understanding the occupational transitions under advanced systems.

In this paper, the authors aimed to understand the changing nature of the operators’ profession within the advanced technological context, and the perceptions and performance-shaping factors of pilots and ATCOs to define the generational changes.

Based on a study of internationally oriented Greek small and medium-sized enterprises (SMEs), and using the lens of institutional theory, this paper extends the understanding of the extent to which Greece's institutional context influences talent management (TM). In so doing, the authors focussed on the key TM practices employed by SMEs to enhance and sustain TM: talent acquisition, development and retention. The authors also explore how these practices are shaped by the Greek institutional context.

Employing a multiple case-study approach, the authors conducted 18 interviews in six distinctive SMEs operating in north, central and southern Greece. The data were thematically analysed to identify patterns across all SMEs.

This study found that unlike multinational corporations, internationally oriented Greek SMEs adopt a more inclusive approach to TM practices as well as that the country's institutional context presented important yet not deterministic hurdles. The authors also found that SMEs adopt an opportunistic approach to talent acquisition by utilising appropriate available sources to reach out for available talent. The authors provided evidence that SMEs adopt a hybrid approach to talent development in addressing talent scarcity. Finally, this study reported that talent retention is significantly appreciated by SMEs, who offer a range of intrinsic and extrinsic incentives to retain their talented workforce.

This study provides stakeholders with insights into how effective TM practices can be considered a lifeline to organisational sustainability – particularly for SMEs in the contemporary challenging and fiercely competitive business environment. It also highlights the potential of inclusive TM practices to be part of an effective workforce management strategy: Relative to the prevailing institutional dynamic, stakeholders (policymakers and human resource practitioners) must engage in the multiple areas of individual talent acquisition, development and retention.

In a context of reforms, this study reports on TM practice in internationally oriented Greek SMEs. The authors also add to the literature on TM in SMEs by providing evidence on the conceptualisation and management of global talent in this context.

The purpose of this paper is to examine consumer attitudes and behavior towards organic products and products produced under the system of integrated management (SIM) and to compare the socioeconomic characteristics and attitudes that affect consumers' willingness to pay (WTP) a premium for these two different certification systems.

The study is based on cross‐sectional data collected through a questionnaire survey. Respondents' attitudes towards the organic and SIM certification systems are examined. A principal component analysis (PCA) with varimax rotation was primarily applied to provide a more manageable set of variables relevant to attitudes. Those attitudes together with socioeconomic factors and variables relevant to respondents' motivations to food consumption were used for the estimation of the WTP for organic and SIM products.

Findings suggest that consumers' level of awareness and information towards the studied certification systems is rather low especially for SIM products. This can be mainly attributed to the inadequate promotion and the low availability of certified products in the Greek market. The study also reveals that the WTP for organic products is higher among consumers who place much importance on health, consume organic fruits/vegetables and get information about food/nutrition issues from doctors/nutritionists/health institutes and magazines. WTP for SIM products is affected mainly by married consumers, regular buyers of organic products and those who consume frequently fruits/vegetables.

This paper provides an outline of the level of awareness and trust of food quality certification systems by Greek consumers, a topic that has not been widely discussed in Greece. The findings can help all the involved bodies to avoid the impediments and develop an adequate marketing strategy for the effective promotion of certified food products.

The purpose of this paper is to investigate the factors that affect the level of job satisfaction that school principals experience and, based on the findings, to suggest policies or techniques for improving it.

Questionnaires were administered to 180 primary school heads in 13 prefectures – one from each of the 13 Greek regions (including the metropolitan area: prefecture of Attiki, Athens) so that the sample would be representative of the whole country. The first section of the questionnaire includes the location of each respondent's school as well as personal and professional characteristics of the primary school teachers, while the second section asked school principals to reply to 36 statements that expressed perceptions relating to their level of job satisfaction. These responses yielded the principal components for factor analysis.

The results indicate that two factors – the role of superior and school heads' remuneration, and recognition of the principals' efforts – which account for 33.27 per cent of the total sample, seem to be particularly important for school heads' job satisfaction.

The findings of this study cannot be used to generalize about the whole Greek education system as it only analyzes a small sample. Therefore, analysis of additional data from school principals may be necessary for comparison and to reaffirm the results. Further investigation is also needed in order to isolate the specific elements and significant differences in school heads' satisfaction ratings.

This paper would be useful to educational planners and policy makers. Meeting the school principals' needs and expectations seems to be a basic component in effective school leadership. As the school principal's role is directly related to human resources management (teachers) and subsequently to child development, the issue of a head's job satisfaction becomes even more pressing.

Given that the existing Greek literature on school management does not contain a substantially detailed discussion specifically on school heads' job satisfaction, this paper may contribute decisively to the smoother and more efficient operation of the school unit.

The aim of the paper is to discuss developments in non-residential real estate in Greece.

Given the lack of existing literature, the authors start by discussing at length the data sources available, and analyzing the stylized facts of non-residential real estate activity in Greece. Finally, the authors examine the degree of covariation (using the index of concordance methodology) between non-residential real estate and the business cycle.

The results indicate that the structure of non-residential sector is highly fragmented into various sub-categories and at the initial stages of its developments, it was strongly affected by the preparations for the 2004 Athens Olympic Games. Finally, despite its small share of total GDP, non-residential real estate exhibits a significant degree of covariation with the business cycle.

The extracted information may be a useful resource for those interested in the developments in non-residential real estate in Greece and the covariation of key variables with the business cycle.

The paper constitutes a systematic research approach for the role of non-residential real estate in the Greek economic activity.