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Article
Publication date: 30 December 2021

Alicia Salazar, Alberto Jesús Cano Aragón and Jesús Rodríguez

Polyamide 12 (PA12) processed by the additive manufacturing technique of selective laser sintering (SLS) is acquiring a leading role in cutting-edge technological sectors…

342

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Rapid Prototyping Journal, vol. 28 no. 5
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 25 July 2019

Alberto J. Cano, Alicia Salazar and Jesús Rodríguez

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…

250

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Rapid Prototyping Journal, vol. 25 no. 5
Type: Research Article
ISSN: 1355-2546

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Book part
Publication date: 12 November 2018

Adriana Perez-Encinas and Jesus Rodriguez-Pomeda

Studies in higher education tend to use different methods and methodologies, from documentary analysis to auto/biographical and observational studies. Most studies are either…

Abstract

Studies in higher education tend to use different methods and methodologies, from documentary analysis to auto/biographical and observational studies. Most studies are either qualitative or qualitative. A mixed-methods approach has emerged in recent years, in which the qualitative approach generally plays an important role. The purpose of this chapter is to show the potential of a new methodology that is also appropriate for higher education research and widely used in the social sciences: probabilistic topic models. A probabilistic method can be used to analyse and categorise thousands of words. After collecting large sets of texts, content analysis is used to deeply analyse the meaning of these words. The huge number of texts published today pushes researchers to employ new techniques in their search for hidden structures built upon a set of core ideas. These methods are called topic modelling algorithms, with Latent Dirichlet Allocation being the basic probabilistic topic model. The application of these new techniques to the field of higher education is extremely useful, for two reasons: (1) studies in this area deal in some cases with a great volume of data and (2) these techniques allow one to devise models in a way that is unsupervised by humans (even when researchers operate on the resulting model); thus they are less subjective than other types of analyses and methods used for qualitative purposes. This chapter shows the foundations and recent applications of the technique in the higher education field, as well as challenges related to this new technique.

Details

Theory and Method in Higher Education Research
Type: Book
ISBN: 978-1-78769-277-0

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Article
Publication date: 1 August 2003

Jesus Rodriguez Perez and Patricia Ordóñez de Pablos

Knowledge management literature highlights the fact that, in the new economy, the achievement of a sustained competitive advantage depends on firm’s capacity to develop and deploy…

22587

Abstract

Knowledge management literature highlights the fact that, in the new economy, the achievement of a sustained competitive advantage depends on firm’s capacity to develop and deploy its knowledge‐based resources. However, not all resources are equally important for the achievement of this competitive edge. In this sense, this paper proposes an integrative framework for the analysis of human capital combining the advances from three different areas of research: knowledge management, intellectual capital, and strategic human resource management. Juxtaposing two dimensions – value and uniqueness – it analyzes the different forms of firm’s human capital. These are the following: idiosyncratic, ancillary, core and compulsory. Furthermore different human resources practices that should be used to manage such specific forms of human capital are described.

Details

Journal of Knowledge Management, vol. 7 no. 3
Type: Research Article
ISSN: 1367-3270

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Article
Publication date: 17 September 2019

Meenu Chopra and Vikas Gupta

The purpose of this study is to develop a decomposed model to inspect the effect of knowledge management practices (knowledge sharing culture [KSC], knowledge-based human resource…

1097

Abstract

Purpose

The purpose of this study is to develop a decomposed model to inspect the effect of knowledge management practices (knowledge sharing culture [KSC], knowledge-based human resource management [KHRM], strategy and leadership [S&L], information and communication technology [ICT] on organizational performance [OP]) by using the four balanced scorecard outcomes (BSC) (learning and growth [L&G], internal process [IP] perspective, customer satisfaction [CS] perspective and financial performance [FP]).

Design/methodology/approach

The research methodology included development of a research model based on comprehensive literature review followed by survey of knowledge-intensive organizations. A sample of 277 employees was obtained and structured equation modeling analysis using SPSS AMOS was conducted to test the proposed hypotheses.

Findings

The study shows that KSC and KHRM have a highly significant effect on all the four aspects of OP; S&L positively and significantly affects only L&G and IP but does not have any significant effect on the other two, i.e. CS and FP, while ICT practices did not affect any of the measures significantly.

Research limitations/implications

The data are limited to 277 middle and senior level managers of Indian firms, which may be a limiting factor for generalizability.

Originality/value

The proposed model uncovers the dynamics of individual relationships between KM practices and measures of performance (proposed by BSC) in comparison to existing models which have mainly focused on the overall effect.

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Article
Publication date: 7 August 2020

Gema Gomez-Casero, Carol Angélica Jara Alba, Tomás López-Guzman and Jesús Claudio Pérez Gálvez

Researchers have become aware of the importance of festivals as a phenomenon worthy of studying, but in-depth studies of cultural festivals are lacking. The purpose of this study…

654

Abstract

Purpose

Researchers have become aware of the importance of festivals as a phenomenon worthy of studying, but in-depth studies of cultural festivals are lacking. The purpose of this study is to describe the attributes of cultural festivals, specifically theatre festivals and examine the motivations to organise them. Similarly, this study seeks to discover the type of tourist that attends these types of festivals.

Design/methodology/approach

A questionnaire was applied to a representative sample of tourists who visited one of the most prestigious festivals in the international panorama: Almagro International Festival of Classical Theatre. A non-probabilistic technical sample was used. Tabulation of the data was performed by the study group using the SPSS, v. 23.

Findings

This study makes a segmentation of the tourists who attend the festival based on their motivations. Using this segmentation, the authors analyse the socio-demographic characteristics and tourists’ behaviour, as well as their experience at the festival. Amongst the higher-rated attributes of the festival are care and service organisation and interpretative quality of the actors and/or theatre company.

Research limitations/implications

The main practical application of this study is to help understand the peculiarities of each segment of visitors and their evaluation of the destination to create tourist and cultural products that provide greater satisfaction with respect to their needs.

Originality/value

The main value is the novelty of studying this kind of cultural event. The authors analyse the reasons to visit it in relation to the motivations that move the visitors. The authors also study the assessment the tourist does of the qualities of the festival.

Details

International Journal of Culture, Tourism and Hospitality Research, vol. 14 no. 4
Type: Research Article
ISSN: 1750-6182

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Article
Publication date: 9 January 2025

Jorge Jimenez Serrano, María Jesús Delgado Rodríguez, Isabel Rodríguez Iglesias and Rafael Manuel López Pérez

The purpose of this article is to deepen on the crime of assets misappropriation (AM) in the company, collecting through a systematic review of the published scientific literature…

39

Abstract

Purpose

The purpose of this article is to deepen on the crime of assets misappropriation (AM) in the company, collecting through a systematic review of the published scientific literature those factors or theories that are being used when writing about this type of crime, as well as the implications for the business context.

Design/methodology/approach

The PRISMA methodology of systematic review has been used, from which 21 articles have been included, all of them published since 2005 in scientific journals related to the financial and economic context, but also to the criminological approach.

Findings

The articles provide several factors that are currently of interest in the study of the crime of AM in the company: the type of company in which this crime occurs, the most frequent types of AM, the elements of prevention used, as well as the profile and characteristics of employees who usually commit this type of crime.

Research limitations/implications

The conclusions of this article show the importance of studying this type of crime to combat it, not only because of the economic implications but also because of how it affects other spheres of the business context. The research has focused exclusively on articles written in English with the keyword “misappropriation assets”, which may have limited the inclusion of other articles of interest, although the objective of this study is precisely to evaluate the scientific interest in this specific type of Fraud.

Practical implications

Conclusions are drawn regarding prevention elements that are currently being used in the company to detect and combat this type of crime, as well as suggestions for future research.

Originality/value

This article seeks to support and encourage the study of this type of crime in business, following the sustainable development goals, which are the global goals designed to eradicate poverty, protect the planet and ensure global prosperity, among which is the promotion of business ethics and transparency in economic activities, for which the crime of misappropriation is a violation of these principles.

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Article
Publication date: 11 June 2024

Jesús F. Lampón, Francisco Carballo-Cruz and María-Elena Velando-Rodríguez

Autonomous and connected mobility technologies have led to a reconfiguration of the automotive industry value chain. This may involve an impact on the geography of the European…

90

Abstract

Purpose

Autonomous and connected mobility technologies have led to a reconfiguration of the automotive industry value chain. This may involve an impact on the geography of the European automotive industry, especially for peripheral countries. The aim of the paper is to analyse the repositioning of a peripheral country (Portugal) in the core-periphery model of the automotive industry derived from this new technological context.

Design/methodology/approach

An eclectic theoretical framework, based on the global value chain (GVC) approach, the spatial division of labour and location theory, supports this research. Moreover, an original empirical study was developed. This study comprised a comparative analysis of two samples of firms based on the key variables related to country position. One sample comprised Portuguese traditional automotive firms and the other Portuguese firms linked to autonomous and connected mobility technologies.

Findings

The results highlight the upgrading of Portugal in the European core-periphery model of the automotive industry. This is due to the presence of domestic firms, especially multinationals, linked to autonomous and connected mobility technologies in the country. The decision power derived from their position on the first levels of supply and the added value of activities and technological innovation of these new actors change the role of the country in the European automotive industry. The main implication is that managers of domestic firms and policy makers in peripheral countries can upgrade a country’s position in the European core-periphery model by shifting its competitiveness toward knowledge-based activities linked to the new mobility technologies.

Originality/value

This research is supported by a novel eclectic theoretical framework based on the global value chain (GVC) approach, the spatial division of labour and location theory. Moreover, country position is analysed through empirical evidence. An original comparative empirical study based on the key variables defined under this theoretical framework was developed.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 10 July 2017

David Rodeiro-Pazos, María Jesús Rodríguez-Gulías and Sara Fernández-López

The purpose of this paper is to explore the survival of university spin-offs (USOs) in Spain. First, the survival rates of USOs are compared with those of a group of similar…

266

Abstract

Purpose

The purpose of this paper is to explore the survival of university spin-offs (USOs) in Spain. First, the survival rates of USOs are compared with those of a group of similar firms. Second, the firm-specific characteristics of surviving USOs are compared with those of failed USOs.

Design/methodology/approach

The study is based on two subsamples consisting of 469 USOs and 469 non-USOs. A matching procedure is used for identifying a valid control group that allows for an outcome comparison between USOs and non-USOs. A longitudinal data set (2000-2010) is constructed, combining data regarding firm-specific characteristics and patent activity. The survival rates of both USOs and non-USOs are described first, and then, the firm-specific characteristics of the surviving USOs are discussed and compared with those of the failed USOs.

Findings

The authors find that the survival rates of the USOs are slightly lower than those of the non-USOs. In addition, the failed USOs have a longer average life span than the failed non-USOs. Finally, the data show that the surviving USOs are more likely to have venture capital investors, exports and patents than the failed USOs.

Research limitations/implications

This study carries out an explanatory analysis of the survival of Spanish USOs. As the results showed no significant differences between the characteristics of the surviving USOs and those that failed, except for subtle differences in the profiles of the two groups, it is necessary to analyse the underlying causes of this situation.

Practical/implications

In many countries, large amounts of public funds have been invested in the creation of USOs. This policy only makes sense if these firms increase the business value and create jobs. The support of USOs with a low expectation of survival or economic viability opens a debate on the amount of public funds invested in these firms. In the current context, funding obtained by these companies could be considered to drain resources from those projects that really deserve to be targeted.

Originality/value

The creation of USOs has become a mainstay of universities’ entrepreneurship strategies. Analysing USOs’ survival is therefore crucial for understanding the contribution of entrepreneurial universities to society. Survival is not another measure of this performance, but it is a pre-condition for university-based entrepreneurship to have an effect on society.

Details

Journal of Enterprising Communities: People and Places in the Global Economy, vol. 11 no. 03
Type: Research Article
ISSN: 1750-6204

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Abstract

Purpose

This paper aims to present and describe the main actions carried out in six different faculties and common areas such as cultural and research centres and administrative buildings in the Ferrol campus at the University of A Coruña to achieve the second green flag on a Galician University.

Design/methodology/approach

A case study describing the steps for implementing a green campus programme in a medium-size, young university campus integrated into a small city. An Environmental Campus Committee was created to assess the main factors that affect environmental footprint, discuss sustainability initiatives and develop a guide to action regarding different goals related to sustainable transport options, energy, water conservation and waste reduction. The actions included several fields such as education, circular economy and healthy life and involved the on and off-campus community.

Findings

The programme achieved a decrease in water consumption and electrical energy. An important change in educational values and behaviours regarding sustainability was observed in and out of the campus community. The measurements adopted mainly in waste management, mobility and education led the Ferrol campus to achieve a green campus flag on November 2019.

Originality/value

This experiment can serve as a guide to establish the Green Campus philosophy in other similar university campuses.

Details

International Journal of Sustainability in Higher Education, vol. 21 no. 7
Type: Research Article
ISSN: 1467-6370

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