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Composite materials and metallic structures already compete for the next generation of single-aisle aircraft. Despite the good mechanical properties of composite materials metallic structures offer challenging properties and high cost effectiveness via the automation in manufacturing, especially when metallic structures will be welded. In this domain, metallic aircraft structures will require weight savings of approximately 20 per cent to increase the efficiency and reduce the CO₂ emission by the same amount. Laser beam welding of high-strength Al-Li alloy AA2198 represents a promising method of providing a breakthrough response to the challenges of lightweight design in aircraft applications. The key factor for the application of laser-welded AA2198 structures is the availability of reliable data for the assessment of their damage tolerance behaviour. The paper aims to discuss these issues.

In the presented research, the mechanical properties concerning the quasi-static tensile and fracture toughness (R-curve) of laser beam-welded AA2198 butt joints are investigated. In the next step, a systematic analysis to clarify the deformation and fracture behaviour of the laser beam-welded AA2198 four-stringer panels is conducted.

AA2198 offers better resistance against fracture than the well-known AA2024 alloy. It is possible to weld AA2198 with good results, and the welds also exhibit a higher fracture resistance than AA2024 base material (BM). Welded AA2198 four-stringer panels exhibit a residual strength behaviour superior to that of the flat BM panel.

The present study is undertaken on the third-generation airframe-quality Al-Li alloy AA2198 with the main emphasis to investigate the mechanical fracture behaviour of AA2198 BMs, laser beam-welded joints and laser beam-welded integral structures. Studies investigating the damage tolerance of welded integral structures of Al-Li alloys are scarce.

The purpose of this study is to examine degree of job satisfaction of the University of Athen’s (UOA) administrative staff, specifically regarding the workplace and its impact on their productivity.

Questionnaires were distributed to 160 administrative personnel of the UOA. The study entails descriptive analysis, independent samples t-tests, ANOVA, Pearson correlations (two-tailed) and regression analysis of the data collected.

The results indicate that the UOA’s administrative staff is dissatisfied with most aspects of their workplace, which is characterized by an inability to encourage and support new forms of office work. This scenario was also found to have a negative effect on productivity. In addition, regression analysis showed that satisfaction with the workplace is a significant predictor of employee productivity.

A limitation of this study is that the sample was not from the UOA administrative staff that works in more recently constructed office buildings away from the Athens city center. Further investigation would also be needed to identify possible differences in satisfaction with the workspace and its impact on productivity, based on demographic characteristics, such as the level of education and years of employment.

The research results may be useful to public institution administrations like that of the UOA, as it highlights changes in the workplace which can have significant impact on employee job satisfaction and productivity, and consequently, the efficiency and effectiveness of the services provided.

This study examines aspects of the workspace of a public organization regarding their individual attributes. Given that the existing Greek literature in this field does not contain a discussion on the impact of the workplace on job satisfaction and productivity as far as the public sector is concerned, this paper may contribute to a smoother and more efficient provision of services from its organizations/institutions.

The purpose of this article is to introduce an innovative methodology to support manufacturing changes in the foundation of flexibility measurements and evaluations and to integrate this in the companies' internal as well as companies' cross‐organisational processes of change management.

The approach consists of two phases: first, a consistent systematics for the production systems flexibility evaluation is presented; second, the change processes are analysed and quantified flexibility indicators are integrated to support the decision – making process.

The application of the methodology in manufacturing environments has demonstrated that consideration of flexibility in the production and its integration into the manufacturing change processes has a great potential.

The originality of this work is in the integrated approach to consider flexibility as support for the change management. In particular the integration of quantified flexibility measurements into the change processes comes out to be the real innovation of the project.