Search results

This paper aims to propose using polylactic acid (PLA) as an alternative to nanocomposites in additive manufacturing processes in fusion deposition modelling (FDM) systems and describe its thermal and rheological conditions with multi-wall carbon nanotube (PLA/MWCNT) and halloysite nanotube (PLA/HNT) composites for possible applications in additive manufacturing processes.

PLA/MWCNTs and PLA/HNTs were obtained through fusion in a co-rotating twin-screw extruder. PLA was mixed with different percentages of MWCNTs and HNTs at concentrations of 0.5 Wt.%, 0.75 Wt.% and 1 Wt.%. Differential scanning calorimetry (DSC) and capillary rheometry were used to characterise these products, together with an analysis of the melt flow index (MFI).

The DSC data revealed that the nanocomposites had a glass transition temperature T_g = 65 ± 2°C and a melting temperature T_m = 169 ± 1°C. The crystallisation temperature of PLA/MWCNTs and PLA/HNTs was between 107 ± 2°C and 129°C, respectively. The viscosity data of PLA/MWCNTs and PLA/HNTs obtained by capillary rheometry indicated that the viscosity of the materials is the same as that of neat PLA. These results were confirmed by the higher fluidity index in the MFI analysis.

This paper presents an alternative for the applications of nanocomposites in additive manufacturing processes in FDM systems.

This paper aims to describe the influence of maleinized linseed oil (MLO), when used as a lubricant, on the thermal and rheological properties of PLA/MWCNTs (polylactic acid/multi-walled carbon nanotubes) and PLA/HNT (halloysite nanotubes) nanocomposites, as a reference for application in 3D printing processes.

Nanocomposites were obtained by melting in a twin-screw extruder, mixing PLA with MWCNTs and HNTs in different percentages of 0.5, 0.75 and 1 Wt.% for subsequent mixing by the same process with 5 phr MLO, for application in additive manufacturing, as analyzed by means of differential scanning calorimetry (DSC), capillary rheometry, melt flow rate (MFL) and field emission scanning electron microscopy (FESEM).

The results obtained for thermal characterization by using DSC indicate the non-variation of glass transition temperature Tg = 62 ± 2°C and a melting temperature (Tm) around 170°C. Crystallization temperature dropped by approximately 12°C, which should be kept in mind during the transformation processes. The values obtained by capillary rheometry indicate that the material’s viscosity is reduced by the influence of the MLO plasticizer’s lubricant effect on the PLA’s molecular structure. The melt flow index values confirm a rise of approximately 46% in the flow index and back up the capillary rheometry results. The values obtained were as follows: PLA/0.5 Wt.% MWCNT/MLO 5 phr 54.07, PLA/0.75 Wt.% MWCNT/MLO 5 phr 53.46, PLA/1 Wt.% MWCNT/MLO 5 phr 51.84y PLA/0.5 Wt.% HNT/MLO 5 phr 61.8, PLA/0.75 Wt.% HNT/MLO 5 phr 68.3 and PLA/1 Wt.% HNT/MLO 5 phr 71.2 g/10 min. Apart from the nanocharge distribution, the information obtained from the FESEM shows the existence of a cluster, which could have been avoided by more energetic stirring during the nanocompound manufacturing process.

This paper presents an analysis of the insertion of plasticizer in nanocomposites for the application in additive manufacturing processes in fusion deposition modelling (FDM) system.

This is a novel original research work.

The purpose of the paper is to present a service design (SD)-based methodology developed to help small and medium enterprises (SMEs) undertake organisational change.

This research used the design science research methodology, which enabled the creation of the Service Design for Organisational Change (SD4OCh) methodology. A real case study of a small service company specialised in neuropsychological disorders was used for the definition and validation of SD4OCh.

The main outcome of this study is the SD4OCh methodology, which is based on three key stages: diagnosis (knowing where to begin by detecting the organisation's strengths and weaknesses), innovation (improving the structure/processes and designing/redesigning services by employing a customer-centric approach), and implementation (enabling the definition of the route towards organisational change). There is also a transversal evaluation stage, which quantifies the organisational changes.

This study adds valuable knowledge to the service science research field and contributes to the awareness of the usefulness of SD theory within companies, especially those which are small and medium-sized, since those companies lack the tools and methods required to tackle organisational change, signifying that the challenges the companies confront are different to those of larger companies.

Although this is a SD-based research, the SD4OCh methodology was developed in order to enable companies to make holistic changes, namely, to innovate their services, structure, and processes, thus supporting and guiding organisational change.

This paper aims to assess how digital knowledge management affects technostress in workers and how that influences the organization’s sustainability. The study applied an in-depth literature review of the following concepts and dimensions, digital knowledge management (acquisition, sharing and application), technostress (techno overload, invasion, complexity, insecurity and uncertainty) and sustainability (economic, social and environmental).

After completing the literature review, an online questionnaire was developed and disseminated through social networks. The questionnaire had four sections: classification of the respondent, questions related to knowledge management, technostress and sustainability. The final sample comprises 454 responses. First, a descriptive analysis of the sample was carried out, and second, a structural equation model by the partial least squares–structural equation modeling method was conducted.

The results show that there is a direct and positive relationship between knowledge management and technostress. This finding means that a higher level of knowledge management of firms causes a greater level of technostress among employees. The close relationship between knowledge management and the firms’ sustainability has also been confirmed. The study results have shown that gender does not have a moderating effect on the relationships reported, as there are no significant differences.

To the best of the authors’ knowledge, this study is the first to look at digital knowledge management, assessing both the levels of employee technostress and the sustainability achieved by their organizations. Thus, this study could serve as a basis for future research. In addition, it contributes to the scarce academic literature on technostress and digital knowledge management levels.

The purpose of this study is to examine the situation of lesbians, gays, bisexuals, transgender, queer and asexual (LGBTQA+) youth in Spain, pre-examining the links between the people they live with, their support networks and their perception of being a burden.

This study traces some brushstrokes through the preliminary results of the LGBTQA+ population between 13 and 21 years old (n = 445). These data are part of a larger project with 2,800+ respondents.

This study’s data highlight the connections between places of cohabitation, support and vulnerability in a crisis situation. In general, gender identity, age, support and feelings of acceptance have been key variables in identifying psychosocial factors related to the health of this population. Lastly, the authors offer some future guidelines to improve the situation of young people in the face of new situations of confinement, incorporating good practices for children and youth services.

The use of the snowball technique for data collection may limit the representativeness of the sample. In the same way that data collection is used through access to an online questionnaire, it can limit access to certain people.

Address the psychosocial needs of LGBTQA+ youth, especially in crisis situations. With our data, we can improve services for future situations of confinement due to coronavirus, planning actions that include the youngest members of this population group, as well as those with non-normative sexualities and identities.

Encourage and diversify support for LGBTQA+ youth from their families, peers, teachers and other professionals working in the youth field. This support would be congruent with the anti-discriminatory and trans-specific legislation existing in most Spanish regions. Furthermore, it would propose a social change that not only benefits LGTBQA+ people, as it allows for a more inclusive cultural change for all in terms of gender and sexuality.

New data obtained within the time frame of the state of alarm are provided, concerning a social group that has been little researched and that finds itself in an unprecedented health crisis.

This study disentangles the impact of consumers’ adoption of mini-program channels on social media on their purchase behavior in e-marketplaces from a multichannel retailer’s perspective and examines the moderating roles of two types of brand messages (informational and transformational messages).

Based on 2,204 transaction records from a Chinese multichannel retailer, this study used a Poisson regression model with fixed effects for empirical testing. The case of the WeChat mini-program in China was employed.

Adopting mini-program channels on social media reduces consumers’ purchase frequency but increases their purchase breadth in e-marketplaces. Moreover, informational messages worsen the negative effect of mini-program channel use on purchase frequency. In contrast, transformational messages reduce the negative effect of mini-program channel use on purchase frequency and amplify its positive effect on purchase breadth.

Managers can effectively leverage mini-programs to widen the range of consumers’ product purchases in e-marketplaces and the intensity of transformation messages posted within mini-programs to alleviate their negative impact on purchase frequency in e-marketplaces.

Previous studies only focus on the intrachannel impact of mini-program channels; however, this study highlights their cross-channel impact. Its findings underscore the dual role of mini-program channel use in e-marketplaces. Additionally, the nuanced moderating effects of informational and transformational messages enrich our understanding of mini-program channels on social media. Moreover, a substitution framework is utilized to understand the cross-channel effects generated by mini-program channels, demonstrating the applicability and generalizability of the framework in a new context.

The purpose of this paper is to explore the relationship between knowledge management and creation of intellectual property within the context of small and medium size manufacturing enterprises.

A hypothesis was formulated and tested using structural equation modelling. Data were collected through an instrument that was developed based on key constructs adapted from the literature and that was first validated using Confirmatory Factor Analysis. A Cronbach’s alpha test was also conducted and the Composite Reliability Index was calculated to ensure reliability of the theoretical model. The instrument was distributed among manufacturing small and medium enterprises (SMEs) in the Aguascalientes region of Mexico, from were 125 valid responses were obtained.

In general, the results indicate that knowledge management has positive effects on the creation of intellectual property in manufacturing SMEs. This suggests that SMEs can create more intellectual property if they dedicate more efforts to the management of knowledge.

The implication of this research and its findings may inform the strategies formulated by policy makers, and the managerial practices that manufacturing SMEs can adopt to protect their knowledge.

Evidence suggests that studies focused on investigating the relationship between knowledge and intellectual property are limited. This paper provides a refined understanding of the relationship between knowledge management and intellectual property creation.

This chapter presents the results of the collective experience of two professors and three students in implementing WebQuests in a preservice English education component. The first part of the chapter provided a definition of WebQuests, situating this particular proposal within the literature on second language education and the Colombian and Latin American contexts. The authors found that the paucity of studies on designing WebQuests, specifically in Latin America, became one of the strengths of their work. The next section situated how implementing WebQuests in this preservice program enabled an expansion of the actual conceptual framework that is currently in place for WebQuests by adding ideas about competences and socio-cultural and critical thinking theories. However, there is an explanation about how WebQuests became a very feasible alternative to respond to the curricular demands of their institution. Next, the authors shared a multi-vocal account, from every author's vantage point, of how they carried out their work with WebQuests. This implementation process generated a series of changes in the way students saw themselves as learners and future teachers, gaining more ownership of the idea of WebQuests beyond a semester assignment. The instructors, as the result of their work, are now thinking of better ways to redefine how they use WebQuests and how they will get their other cohorts involved in collaborative academic efforts. This chapter is, then, not only an account of an experience, but an invitation to think about how to expand the boundaries of preservice teacher education through technological mediation.

Organizations depend on multiple factors to maintain competitiveness and continuously adapt to the environment. Managers must know how to implement strategies while motivating the commitment of those involved. This study aims to present a model for prioritizing factors to promote effective strategy implementation in small- and medium-sized companies.

The authors adopted a systemic approach to articulate two instruments: social network analysis to identify the components that could affect strategy implementation, designing a conceptual model with this information, and analytical hierarchy process to validate the resulting construct.

The factors for effectively implementing strategies relate to the need for reinforcement, commitment, organizational culture, managerial skills, clear communication and involvement to reduce inconsistencies between the expected and current organizational state without neglecting coordination and management mechanisms.

This work is limited to organizational matters. This study was conducted in collaboration with medium-sized Mexican companies with the participation of 94 managers with 10 years of experience. Although the results are mathematically rigorous, increasing the number of participants could enhance the approach to the problem.

This study could encourage academics and practitioners to target resources more accurately and improve organizational relationships to bridge the gap between strategic planning and practical implementation.

This study contrasts with previous research in proposing a systemic perspective that integrates participants’ experiences, developing a construct to determine and prioritize the factors to be addressed in strategy implementation. Therefore, this work invites the adoption of the proposed method as a complementary path to enrich academic and professional exchange.

The construction sector has significantly evolved in recent decades, in parallel with a huge increase in the amount of data generated and exchanged in any construction project. These data need to be managed in order to complete a successful project in terms of quality, cost and schedule in the the context of a safe project environment while appropriately organising many construction documents.

However, the origin of these data is very diverse, mainly due to the sector’s characteristics. Moreover, these data are affected by uncertainty, complexity and diversity due to the imprecise nature of the many factors involved in construction projects. As a result, construction project data are associated with large, irregular and scattered datasets.

The objective of this chapter is to introduce an approach based on a fuzzy multi-dimensional model and on line analytical processing (OLAP) operations in order to manage construction data and support the decision-making process based on previous experiences. On one hand, the proposal allows for the integration of data in a common repository which is accessible to users along the whole project’s life cycle. On the other hand, it allows for the establishment of more flexible structures for representing the data of the main tasks in the construction project management domain. The incorporation of this fuzzy framework allows for the management of imprecision in construction data and provides easy and intuitive access to users so that they can make more reliable decisions.