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Polyamide 12 (PA12) properties meet specific requirements for various applications in the automotive and aerospace industries. Bulk specimens made of PA12 and processed via the additive manufacturing technique such as selective laser sintering (SLS) present a layered structure. In case of structural applications, the fatigue performance of SLS PA12 parts is of vital importance and fatigue response studies in these type of materials are still scarce. Therefore, the purpose of this paper is to analyse the effect of the applied load orientation on the fatigue crack propagation behaviour of the layered structure of SLS PA12.

With the aim of understanding the effect of the applied load with respect to the layer orientation on the fatigue crack growth of SLS PA12, fatigue crack growth tests were carried out at two orientations. The specimens called PARA were orientated in such a way that the applied force direction belongs to the layer plane while in the group called PERP, the tensile force direction is coincident with the build direction, that is, perpendicular to the slice. Besides, special attention has been paid to the analysis of the fracture surfaces of the specimens, linking the micromechanisms of failure with the microstructure of the material.

The SLS PA12 specimens tested with the load applied parallel to the layered structure show a little better fatigue response than those tested at perpendicular orientation. The fracture surfaces of the specimens tested at perpendicular orientation are slightly smoother than those tested at parallel orientation. Crazes are the main micromechanism of failure with a crater size of 50 microns, which coincide with the spherulite size. This indicates that the void nucleation of the crazes takes places between lamellae inside the spherulites, and consequently, the craze growth and rupture occurs mainly in a transspherulitic mode.

PA12 parts manufactured via SLS are becoming more valuable in structural elements in the automative and aeronatical fields. In such applications, fatigue performance is vital for design. Fatigue studies are scarce in literature and even more when dealing with fatigue crack growth behaviour. The value of this work is the analysis of the fatigue crack growth response of these materials taking into account the anisotropic microstructure and to get a better understanding, this behaviour is explained taking into account the micromechanisms of failure and the microstructure of the material.

Polyamide 12 (PA12) processed by the additive manufacturing technique of selective laser sintering (SLS) is acquiring a leading role in cutting-edge technological sectors pertaining to transport and biomedical among others. In many of these applications, design requirements must ensure fatigue structural integrity. One of the characteristic features of these SLS PA12 is the layer-wise structure that may influence the mechanical response. Therefore, this paper aims to assess the fatigue life behavior of PA12, focusing on the effect of the load direction with respect to the load orientation.

With the aim of analyzing the effect of the load direction with respect to the layer wise structure, fatigue tests on plain samples of SLS PA12 were carried out with the load applied parallel and perpendicular to the layer planes. The S-N stress life curves and the fatigue limit at 106 cycles were determined at room temperature and at a stress ratio of 0.1. The fracture surfaces were inspected to evaluate the damage evolution, modeled via the fracture mechanics methodology to obtain the fracture parameters.

The fatigue resistance was better when the load was applied parallel than when was applied perpendicularly to the layered structure. The analysis of the postmortem specimens evidenced three regions. The inspection of the fatigue macro crack growth region revealed that crazing was the mechanism responsible of nucleation and growth of damage till a macroscopic crack was generated, as well as of the consequent crack advancement. The calculated fracture parameters computed from the application of the fracture mechanics approach were similar to those obtained from standardized fracture tests, except when the stress levels were close to the yield strength.

The fatigue knowledge of polymers, and especially of polymers processed via additive manufacturing techniques, is still scarce. Therefore, the value of this investigation is not only to obtain fatigue data that could be used for structural design with SLS PA12 materials but also to advance in the knowledge of damage evolution during the fatigue process.

This chapter aims to contribute to the study of social protests around the world and particularly in Latin America during the 1960s and 1970s, with a focus on an Argentinean case. Throughout these years, Argentina like many other Latin American societies witnessed the growth and development of intense social and political struggles in concert with the armed insurgency. Did workers or other popular social sectors support guerrilla organizations in Argentina? What was the interconnection between working-class and armed insurgent struggle? This chapter examines these liaisons by studying the case of an industrial city that has been identified to be a paradigm of labor radicalization and political violence in Argentina—Villa Constitución. Through the reanalysis of documents and sources as well as interviews, we discuss established interpretations on armed and labor struggles that reveal a broader heterogeneity in the forms of social support to revolutionary violence. Solidarity among workers and armed militants appears in (1) the actions of militant workers at their workplaces, and (2) the armed actions organized by militants in support of worker’s fights.” These two groups reinforced each other's activism. But, by no means can we directly deduct from this that rank and file workers immediately identified their strikes with ideologically revolutionary objectives.

Artisan gastronomy is becoming increasingly important in a destination’s tourism competitiveness. The aim of this chapter is to discuss why artisan gastronomy is important in developing new innovative tourism attractions. To do this, the reasons why tourists like local food and the way this increases the cultural attractiveness of a region are stated. This is important particularly for countries like Spain that derive their competitiveness from artisan gastronomy. The role of artisan gastronomy is stated in terms of Tenerife in Spain. Managerial suggestions are also stated.

The purpose of this paper is to provide an integrative picture of the state of the art of the literature on digitalisation of small and medium-sized enterprises (SMEs) as an enabler for their internationalisation process and as a comprehensive view of the specific domains impacted by digital technologies as well as their repercussions on the international outreach.

A systematic review which leverages a descriptive analysis of extant literature and an axial coding technique has been conducted to shed light on the current knowledge and to identify primary research areas and future research lines.

The research indicates that digitalisation impacts the internationalisation of SMEs in three specific domains: (1) internationalisation through the adoption of information and communication technologies (ICT) technologies and e-commerce platforms; (2) international expansion through the digitalisation of value chain activities and (3) international outreach through knowledge acquisition on digital platforms.

The value of this study is threefold. First, the authors attempt to systematically review the literature on SMEs digitalisation and internationalisation and provide a holistic perspective on the intertwining of these two research streams. Second, the authors propose a novel conceptualisation on the dimensions of SMEs digitalisation as enablers to internationalisation. Third, the authors put forward promising future lines of research.

1. Digitalisation represents a pivotal strategy that allows companies to build new strategic capabilities and is a propeller for SMEs internationalisation.

2. Through e-commerce, SMEs could compete at the same level of multinational companies but enduring lower costs of expansion.

3. Digital platforms allow SMEs to enhance the learning processes about international markets through an immediate access to relevant information.

4. Digital entrepreneurship has enabled SMEs to develop new configurations of value chain activities, evolving their business model or reaching new markets.

5. SMEs are changing the “business as usual” paradigm offering digital tools to build modular architectures that are scalable and agile in their evolution ability.

Digitalisation represents a pivotal strategy that allows companies to build new strategic capabilities and is a propeller for SMEs internationalisation.

Through e-commerce, SMEs could compete at the same level of multinational companies but enduring lower costs of expansion.

Digital platforms allow SMEs to enhance the learning processes about international markets through an immediate access to relevant information.

Digital entrepreneurship has enabled SMEs to develop new configurations of value chain activities, evolving their business model or reaching new markets.

SMEs are changing the “business as usual” paradigm offering digital tools to build modular architectures that are scalable and agile in their evolution ability.

This research investigates the effect of accessibility to points of tourist interest (buffer) and direct and indirect spatial spillover effects of agglomeration economies on tourism industry revenues in Spain.

Data were collected from the Bureau van Dijk's (BvD) Orbis global database. The data were analysed using a spatial econometric model and the Cobb–Douglas production function.

This study reveals that hotels located inside the buffer zone of points of tourist interest achieve better economic outcomes than hotels located outside the buffer. Furthermore, the results show that there is a direct and indirect spatial spillover effect in the hotel industry.

The results provide valuable information for identifying areas where the agglomeration of hotels will produce a spillover effect on hotel revenue and the area of influence of location characteristics. This information is relevant for hotels already established in a destination or when seeking a location for a new hotel.

The results of this study can help city planners in influencing the distribution of hotels to fit desired patterns and improve an area's spatial beauty.

The paper provides insights into how investment, structural characteristics, reputation and location affect hotel revenue.

Responding to local, regional and international demands and initiatives, the government of Ecuador has rolled out an innovative program Sistema Integral de Tecnologías para la Escuela y la Comunidad (SíTEC) to place information, and communication technologies (ICTs) into the hands of students, teachers, and other educational institutions. SíTEC draws upon several elements of social entrepreneurship and has successfully reached some of the most regionally remote and culturally diverse communities in the country. The SíTEC program is emblematic of many of the criteria set forth regarding social entrepreneurship including the vision of leadership, the focus on a social mission and the importance of innovation in partnership and resource allocation. This study looks at survey and interview data from the Shiña community teachers and school leaders to determine the effects of the SíTEC program and the availability and use of ICTs in schools, SíTEC has equipped public schools with computers, projectors, digital boards, and Internet. Additionally, SíTEC organizes training courses on ICTs for public school teachers and provides schools with educational software available in Spanish, Kichwa, Shuar, and English. While there is still much work to be done, SíTEC and the associated partnerships and programs are beginning to have impact in their specified outcomes. Creative partnerships developed within the Ministry of Education, Office of Bilingual Education, Shiña community have allowed for communication and exchange of knowledge and resources across multiple partners. This chapter explores SíTEC as an innovative government-based program that meets targeted social outcomes in ICTs and education.

The purpose of this paper is to introduce and develop a knowledge base for the restoration industry to understand and deal with risks arising in restoration projects in a sustainable way. Restoration projects face a number of risks and are viewed unfavorably. The research study, therefore, is expected to generate interest and debate among the professional and researcher community in the arena of restoration of built cultural heritage for formally applying Project Management (PM) and Project Risk management (PRM) theories and practices.

The research method consists of reviewing published literature and analyzing the dynamics of restoration industry (both from academic and practitioner point of view) in order to propose an application framework. Building upon and taking inspiration from the fundamentals of Construction Management, the proposed framework aims at methodically applying risk management within the proposed PM stages.

Research results confirm that the restoration industry has not yet exposed to formal PM and PRM theories and practices to a greater level. The restoration projects are not necessarily so sustainable in their approach. Thus, there is enormous impetus and ensuing incentive for incorporating the formal theories and customized tools.

This research attempts to target the exceedingly important area of cultural heritage restoration and the missing aspect of PM and PRM. Further, the proposed framework is an attempt at bridging communication gaps between management and restoration experts. Thus, it highlights the importance of scientifically and effectively managing restoration projects. Nevertheless, this uniting attempt has its own risks in terms of terminologies, technical language, and the understanding of risk and its management which may be the effective limitations. Since in the field of engineering as well, the foundation of PM and PRM areas of knowledge finds its traces in Construction Management – which is further an application of management in construction engineering – therefore, it is rather challenging to reconcile knowledge from different areas.

The paper explores issues concerning sustainability of restoration projects based on their use of PM and PRM. Results are expected to help stakeholders of restoration projects understand and apply the proposed PRM framework. This study is also aimed to develop a foundation for dissemination of PM and PRM knowledge in the restoration industry, and provide an impetus for future studies to examine how restoration projects can deal with risky situations.

The paper explores the sustainable development aspects of restoration projects in order to help stakeholders of built cultural heritage make critical decisions because if not managed properly, risks in a restoration project may either cause project failure or damage the historical buildings. Therefore, from a sustainable perspective, it is imperative that stakeholders identify, analyze, control and manage risks before commencing the restoration activities.

The study is an original effort in examining the penetration of PM and PRM practices in restoration industry. Based on it, the study proposes an original framework for application of formal PRM for restoration projects. Results are of relevance in today's world where risks hinder and sustainability guides the decision making.