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Owing to the operating principle of powder bed fusion processes, selective laser sintering (SLS) requires effective management of the mixture ratio of processed material previously exposed to the high temperatures of processing with new virgin material. Therefore, this paper aims to fully understand the effect that the successive reprocessing has in the powder material and to evaluate its influence on the properties of SLS parts produced at different building orientations.

Polyamide 12 material with 0%, 30% and 50% of virgin powder and parts produced from them were studied through five consecutive building cycles and their mass, mechanical, thermal and microstructural properties were evaluated. Then, the experimental data was used to validate a theoretical algorithm of prediction capable to define the minimum amount of virgin powder to be added on the processed material to produce parts without significant loss of properties.

Material degradation during SLS influences the mass and mechanical properties of the parts, exhibiting an exponential decay property loss until 50% of the initial values. The theoretical algorithms of reprocessing proved the appropriateness to use a mixture of 30% of virgin with 70% of processed material for the most common purposes.

This paper validates a methodology to define the minimum amount of virgin material capable to fulfil the operational specifications of SLS parts as a function of the number of building cycles, depending on the requirements of the final application.

The use of theoretical models of prediction allows to describe the degradation effects of SLS materials during the sintering, ensuring the sustainable management of the processed powder and the economic viability of the process.

With the technological progress, high-performance materials are emerging in the market of additive manufacturing to comply with the advanced requirements demanded for technical applications. In selective laser sintering (SLS), innovative powder materials integrating conductive reinforcements are attracting much interest within academic and industrial communities as promising alternatives to common engineering thermoplastics. However, the practical implementation of functional materials is limited by the extensive list of conditions required for a successful laser-sintering process, related to the morphology, powder size and shape, heat resistance, melt viscosity and others. The purpose of this study is to explore composite materials of polyamide 12 (PA12) incorporating multi-walled carbon nanotubes (MWCNT) and graphene nanoplatelets (GNP), aiming to understand their suitability for advanced SLS applications.

PA12-MWCNT and PA12-GNP materials were blended through a pre-optimized process of mechanical mixing with various percentages of reinforcement between 0.50 wt.% and 3.00 wt.% and processed by SLS with appropriate volume energy density. Several test specimens were produced and characterized with regard to processability, thermal, mechanical, electrical and morphological properties. Finally, a comparative analysis of the performance of both carbon-based materials was performed.

The results of this research demonstrated easier processability and higher tensile strength and impact resistance for composites incorporating MWCNT but higher tensile elastic modulus, compressive strength and microstructural homogeneity for GNP-based materials. Despite the decrease in mechanical properties, valuable results of electrical conductivity were obtained with both carbon solutions until 10^–6 S/cm.

The carbon-based composites developed in this research allow for the expansion of the applicability of laser-sintered parts to advanced fields, including electronics-related industries that require functional materials capable of protecting sensitive devices against electrostatic discharge.

The purpose of this paper is to develop and test an extension of a previously conceived framework for improving and embedding project management (PM) practice in organisations. The framework identifies the most useful project management improvement initiatives (PMIIs) and the key factors for embedding PM practice. However, professionals need guidance on how to operationalise such framework in their organisations, therefore a method for applying the framework is developed.

The method being proposed for applying the framework is demonstrated and tested with a large University–Industry consortium case study. During the case study analysis three research methods were applied: participant observation, document analysis and focus groups.

In what concerns both the PMIIs and key embedding factors in the framework, the proposed method comprises their acknowledgement, scoring, relevance analysis, selection and planning. The detailed report on how the framework was applied in the particular case study also sheds light on how University–Industry consortiums can make use of PM to become more successful.

The research was performed using only one case study which limits the generalisability of its findings.

Detailed guidance is provided for applying the framework’s both constructs, “improving” and “embedding”, through a set of clear steps.

The paper shows the explanatory power of the framework for improving and embedding PM practice in a case study, demonstrating that the method for its application is practical and suitable.

We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.

The survival of companies today hinges on their adaptability and flexibility, with digital transformation (DT) and organizational slack (OS) playing crucial roles. Despite their recognized importance, these factors are often studied separately. This study aims to explore how OS facilitates DT and evaluate their synergies and trade-offs to improve performance.

Using data from the European Manufacturing Survey, structural equation modeling (PLS-SEM) and fuzzy set qualitative comparative analysis (fsQCA), we investigate causal relationships and possible combinations between different dimensions of OS and DT that contribute to business performance.

We confirmed the positive effect of OS and DT on business performance, highlighting the importance of organizational over technological factors. While not definitively establishing OS as a precursor to DT, our findings underscore the need for human and operational slack to improve performance, especially in less technology-intensive contexts.

Our findings evidence that decision-makers should integrate OS with DT initiatives to improve the firm’s competitiveness. However, it is worth noting that while OS seems essential in low-tech shopfloors, its importance is lower in high-tech environments. Furthermore, within the possible combinations, managers should promote operational slack and digitalization, as it seems fundamental to improve business performance.

This article contributes to the management field in three ways. First, it clarifies controversies by providing evidence of the positive roles of DT and OS as drivers of competitiveness for manufacturing firms. Second, we verify that OS is not directly linked to DT, challenging existing assumptions. Third, it investigates the combinations of OS and DT that drive business performance improvement, emphasizing their synergies and trade-offs.

This study aims to analyze the mediating role that green practices (GPs) and green technologies (GTs) play in the relationship between lean manufacturing (LM) and industrial performance (IP). It is suggested that GPs and GTs are crucial for transforming lean routines into enhanced performance that simultaneously meet current environmental requirements.

The hypotheses are tested using a mixed methodology, which includes a partial least squares structural equation modeling approach and a fuzzy-set qualitative comparative analysis (fsQCA) applied to a multisectoral sample from three European countries (Spain, Sweden and Croatia).

The results confirm that GPs mediate the relationship between LM and IP; however, in the case of GTs, this mediation does not appear to occur, although GTs emerge as a peripheral condition in the subsequent fsQCA. These findings highlight the need to avoid an exclusively technocentric approach and underscore the importance of implementing green organizational practices alongside technology investments to achieve successful lean initiatives.

It seems clear that managers should apply GPs, combined with LM, to improve sustainability and efficiency and should apply GTs once a more mature lean-green culture has been established.

In recent years, the scientific community has increasingly focused on the impact of implementing GPs and GTs on IP within LM plants. However, to the authors’ knowledge, no study has yet analyzed the combined effect of both initiatives. This paper seeks to address this gap by examining, in aggregate, the moderating effect of GPs and GTs on IP in LM plants.

This work aims to examine the communication on Twitter of the most responsible companies in Spain to identify the topics covered on corporate social responsibility (CSR) from the perspective of happiness and social marketing. In addition, the profiles of the messages that show an association with the impact of the messages have been identified.

An empirical analysis of the Twitter posts of Spain's ten most responsible companies has been carried out. The methodology of this work combines data mining techniques, sentiment analysis and content analysis, both from a quantitative and qualitative approach.

The results show that most brand tweets do not deal with CSR-related topics. The topics they address the most are those related to sports and the weather. From the perspective of social marketing, conversational-type tweets are the most published and have achieved the most significant reaction from the public. In addition, four messages' profiles have been identified based on the company and the emotional connotation associated with the impact, giving rise to more outstanding promotion of social causes.

Our main contribution to this work has been to value positive communication and social marketing to promote better CSR on Twitter. In this sense, it has been verified that there is a relationship between the public's reaction, the affective connotation and the company that issues the messages.

The purpose of this paper is to present the application of Design of Experiments techniques for the analysis of operating parameters of an industrial oven for the heat treatment process of polyethylene terephthalate (PET) bottle filaments.

The focus is on evaluating new ways of operating the transformation process. The main issue is to raise what are the variables interfering with the performance of the oven. The complete 2k factorial for three factors of control was used to analyze the behavior of these variables and their relationships in the specific response parameter for the process.

The results presented in this work allow the company to have greater knowledge about the operation of the equipment. The study showed possibilities of 14.8% energy reduction.

The heat treatment activity was characterized as a critical point in the production process, and techniques with empirical approaches, based on statistical techniques, was an opportunity that the company has to improve the execution of activities without major investments for the quality of the final product. The application of statistical quality techniques showed to be very promising.

The fact that the study was conducted using subjective quality performance makes this work different from others presented in the literature, showing the possibility to apply Design of Experiments using main control factors based on the opinion of experienced personnel involved in the process analyzed.

This chapter is designed with the aim to determine the influence of sociodemographic variables on the capacity to generate social enterprises, such as sex, the student’s country, if only they study or if they study and work, as well as if they participate or direct a social enterprise in university students of Latin American business schools. This research adopted an inductive quantitative approach using a questionnaire. The participants were university students of business schools from Colombia, Mexico and Peru. Second-generation structural equation method (SEM-PLS) was used to analyse the results, using the SmartPLS 3.2.7 software applied to data on 3,739 university students. The results suggest that the entrepreneur role, labour situation, country and sex have a moderating effect in the relation between entrepreneurial orientation and entrepreneurial intention. Also, by using resampling technique Bootstrapping (5,000 times,p < 0.01), significance of the trajectory coefficients (beta) and effect size of the coefficients (beta) were measured to demonstrate significance. Finally, with this research the authors ascertain that entrepreneurial orientation positively influences entrepreneurial intention. thus explaining 42.4% of its variance. This chapter is the first attempt on investigating in university students of Latin American business schools about factors of entrepreneurship orientation and entrepreneurship intention, and has strong potential to contribute to development of policies and strategies to promote the growth of entrepreneurship activities in the universities.