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This study aims to present a vision-guided robotic system design for application in vat photopolymerization additive manufacturing (AM), enabling vat photopolymerization AM hybrid with injection molding process.

In the system, a robot equipped with a camera and a custom-made gripper as well as driven by a visual servoing (VS) controller is expected to perceive objective, handle variation, connect multi-process steps in soft tooling process and realize automation of vat photopolymerization AM. Meanwhile, the vat photopolymerization AM printer is customized in both hardware and software to interact with the robotic system.

By ArUco marker-based vision-guided robotic system, the printing platform can be manipulated in arbitrary initial position quickly and robustly, which constitutes the first step in exploring automation of vat photopolymerization AM hybrid with soft tooling process.

The vision-guided robotic system monitors and controls vat photopolymerization AM process, which has potential for vat photopolymerization AM hybrid with other mass production methods, for instance, injection molding.

A local company producing aluminum profile encounters frequent failures to bridge dies. In total, 22 dies failed within a year, entailing production disruptions and extensive downtimes. Bridges usually exhibit cracks on the ribs. The failure analysis of the failed parts has been performed in order to propose solution for correct and economical process. The paper aims to discuss these issues.

Recorded history was collected regarding tool’s material selection, manufacturing conditions, usage and service. A representative failed bridge was in depth analyzed. The piece was optically inspected. Rockwell hardness measurements and chemical analysis were performed. The paper is focussed on the microscopic examination of the failed parts. Specimens were cut from bridge’s ribs. Areas including cracks were analyzed on the cross section of the samples by optical and scanning electron microscopy. Local chemical analysis was made by X-ray microanalysis.

Design, deficiency and improper maintenance are considered to be responsible for the systematic die damage. Prolonged preheating duration and poor quality surfaces before nitriding render dies premature unusable. The preheating duration should be controlled and protective atmosphere should be used. Furthermore, it is suggested to protect the ribs during nitriding as a preventive measure against crack initiation. The bridge’s geometry can be improved by fabricating ribs with larger radii. A finer polishing is recommended.

The present analysis resolved a serious deficiency in extrusion production. Extended research has been conducted in the field of aluminum extrusion dies, nevertheless, the present work presents new metallographic aspects as well as some interesting notes regarding the repetitive nitriding of bridge dies.

Despite increased academic research interest on how media sources represent and impact social realities, there is little emphasis on homelessness representations in street newspapers. The Greek economic crisis echoed socioeconomic changes and inequalities in both mainstream and lesser-known media with various framing representations of homelessness. One Greek journalistic effort born midcrisis was the street paper ‘Schedia’, which merits examining for its popularity and success as a component of the social reintegration program that launched it. Through the lens of our case study on Schedia and drawing mostly on contemporary interdisciplinary approaches from Cultural Studies and Media Communication, we provide a brief literature review on ‘homelessness street journalism’ research and explore theoretical interpretations thereof. We then discuss media discourse and framing of homelessness and whether it reveals utilisation of street journals mainly as tools for raising awareness or for creating income to maintain or augment social reintegration efforts and programs. We content analysed one year of Schedia's issues and examined instances of both perceived and experienced homelessness representations and causes therein, offering a snapshot of the ways and extent to which Schedia represents homeless voices. Lastly, through the example of Schedia, we discuss whether street media lends itself best as a voice for democratic empowerment of the homeless or as an identity-building intermediary tool for capacitating transformative social reintegration.

This chapter theorises the Internet in Greece by placing it at the centre of Greek media offering a political economy which recasts it in a culturalist fashion. To achieve this, it critically addresses the country's alleged lag in cyberspace and asks why the Internet's hegemonic role in the advance of neoliberal policies and technoliberalism worldwide was never performed in Greece. It places the countrywide disdain for the technoliberal subject at the core of understanding of why the web mediations where so neatly denied over three decades across industry, policy and research. It centres around Internet remediations to argue that the Internet in Greece has been conceptualised as a nonmedia through the idea of lagging behind, essentially a construct veiling neoliberalism at work. It situates the advent of the web in Greece's media boom to argue that media power, as articulated in Greece, necessarily excluded the web, fetishising terrestrial broadcasting on the way to the neoliberal dismantling of culture, the media and everyday life, way before the Troika.

The purpose of this paper is to investigate certain social and psychological parameters and to compare them with basic demographic information, such as the gender and the education, of patients suffering from Type 2 diabetes mellitus (T2DM).

A cross-sectional study of Type 2 diabetic patients was conducted. In total, 200 patients with T2DM were enrolled in the study. Psychological factors were assessed with questionnaires, including the Symptom Checklist 90-R (SCL-90-R), the Short-Form Health Survey (SF-36), the Life Orientation Test-Revised (LOT-R) and the Cardiac Anxiety Questionnaire (CAQ). The associations of psychological with socio-demographic factors were assessed through logistic regression analyses.

Women patients had higher levels of heart-focused anxiety psychopathology than men, and therefore, women tend to avoid activities that burden the heart. Men patients had a significantly higher index of physical functionality than women. No differences were recorded by the SCL-90R questionnaire between men and women. For the patients with elementary education, lower levels of mental health (SF-36-MCS) were observed.

The chronicity of the disease aggravates the psychopathology of the patients thereby creating adverse impact not only on health but also on efforts for compliance. A personalized approach by the health professionals could contribute in addressing the psychological factors that accompany T2DM.

The volatile tax system is a huge disincentive for taking business, as frequent changes in the tax system create extremely difficult problems. It is a major barrier to entrepreneurship, it fails to address them economic inequalities, is too complex, changing very often, and is made in a way that facilitates tax evasion.

The factors that discourage investors from investing in our country are as follows (as research has shown in the past five years in our country by researchers and scientists): high taxation, complex institutional framework, bureaucracy, corruption, political liquidity and limited access to finance. These pathogens hamper the ability of the economy to produce competitive goods and quality services on the market.

The purpose of this paper is to investigate the main pathogens of the tax system which are a brake on the development of Greek entrepreneurship and how they can be tackled so that our country produces competitive goods and quality services.

The authors construct an index of economic policy uncertainty (EPU) for Greece using textual analysis and analyze its role in the 10-year Greek economic crisis.

To identify the causal relationship between various measures of economic activity and EPU in Greece, the authors use a sophisticated “shock-based” structural vector autoregressive identification scheme. Additionally, the authors use two additional models to ensure the robustness of the results.

EPU is negatively associated with domestic economic activity and economic sentiment, and positively with bond credit spreads. EPU is also estimated to have prolonged the crisis even in periods when macroeconomic imbalances were cured. The results are robust across various model specifications and different proxies of economic activity.

Brunnermeier (2017) observed that uncertainty may be central to understanding the evolution of the Greek crisis. Yet little attention has been paid to policy uncertainty in the existing long and growing literature on the Greek crisis. The authors attempt to fill this gap.

Looking back on the last 12 years, the whole planet went through two major economic crises (2008 and 2019), which both had a profound impact on the survival of businesses. The present study aims to develop and empirically test a conceptual framework that investigates the factors that have an influence on firm survival. More specifically, the study proposes a three-dimensional framework that includes performance drivers (utilizing resource-based view [RBV] factors), performance measures and the measurement of firm survival. Such a multi-dimensional approach has very rarely been explored in the existing literature.

A thorough literature review revealed gaps in the literature and offered the basis for developing the proposed conceptual framework of the study. Its empirical examination (hypothesis testing) was conducted with the use of a newly developed structured questionnaire that was distributed to a group of Greek manufacturing organizations (the final sample consists of 364 manufacturing companies). Empirical data were analyzed using the “structural equation modeling” (SEM) technique (multivariate analysis) and other similar techniques (i.e. exploratory factor analysis and analysis of variance). The study is empirical (based on primary data), explanatory (examines cause and effect relationships), deductive (tests research hypotheses) and quantitative (includes the analysis of quantitative data collected with the use of a structured questionnaire).

On the one hand, empirical results point out that “manufacturing-marketing alignment,” “manufacturing capabilities,” “structural configuration” and “business performance under crisis” have the most significant impact and on short-term survival (current situation). On the other hand, “competitive advantage” and “business performance under crisis” have the most significant impact on long-term survival (future situation). Focusing on RBV factors, only “structural configuration” and “manufacturing capabilities” directly affect short-term survival, while “manufacturing–marketing alignment” has an indirect effect on the same factor. Then again, all RBV factors indirectly affect long-term survival. Also, it is confirmed that short-term survival strongly affects long-term survival.

The present study contributes to the debate concerning the antecedents of firm survival, since current empirical findings are quite inconsistent. Specifically, crucial performance drivers and other measures are incorporated into an original model, which reveals their synergies and their impact on the dynamic dimensions of firm survival. Additionally, it enhances the stream of research that investigates firm survival under crisis since very few similar empirical studies have been conducted. Finally, firm survival is not measured as a static concept but rather as a dynamic one (firm survival – current situation and firm survival – future situation). Overall, the final model can explain 35.2% of the variance in “firm survival – current situation” and 46.3% of the variance in “firm survival – future situation.”