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The purpose of this study is to evaluate and compare the mechanical performance of FFF parts when subjected to post processing thermal treatment. Therefore, a study of the annealing treatment influence on the mechanical properties was performed. For this, two different types of Nylon (PA12) were used, FX256 and CF15, being the second a short fibre reinforcement version of the first one.

In this study, tensile and flexural properties of specimens produced via FFF were determined after being annealed at temperatures of 135°C, 150°C or 165°C during 3, 6, 12 or 18 h and compared with the non-treated conditions. Differential scanning calorimetry (DSC) was performed to determine the degree of crystallinity. To evaluate the annealing parameters’ influence on the mechanical properties, a full factorial design of experiments was developed, followed by an analysis of variance, as well as post hoc comparisons, to determine the most significative intervening factors and their effect on the results.

The results indicate that CF15 increased its tensile modulus, strength, flexural modulus and flexural strength around 11%, while FX256 presented similar values for tensile properties, doubling for flexural results. Flexural strain presented an improvement, indicating an increased interlayer behaviour. Concerning to the DSC analysis, an increase in the degree of crystallinity for all the annealed parts.

Overall, the annealing treatment process cause a significant improvement in the mechanical performance of the material, with the exception of 165°C annealed specimens, in which a decrease of the mechanical properties was observed, resultant of material degradation.

The purpose of this paper is to prove and qualify the influence of textured surface substrates morphology and chemical composition on the growth and propagation of transplanted corals. Use additive manufacturing and silicone moulds for converting three-dimensional samples into limestone mortar with white Portland cement substrates for coral growth.

Tiles samples were designed and printed with different geometries and textures inspired by nature marine environment. Commercial coral frag tiles were analysed through scanning electron microscopy (SEM) to identify the main chemical elements. Raw materials and coral species were selected. New base substrates were manufactured and deployed into a closed-circuit aquarium to monitor the coral weekly evolution process and analyse the results obtained.

Experimental results provided positive statistical parameters for future implementation tests, concluding that the intensity of textured surface, interfered favourably in the coralline algae biofilm growth. The chemical composition and design of the substrates were determinant factors for successful coral propagation. Recesses and cavities mimic the natural rocks aspect and promoted the presence and interaction of other species that favour the richness of the ecosystem.

Additive manufacturing provided an innovative method of production for ecology restoration areas, allowing rapid prototyping of substrates with high complexity morphologies, a critical and fundamental attribute to guarantee coral growth and Crustose Coralline Algae. The result of this study showed the feasibility of this approach using three-dimensional printing technologies.

The purpose of this paper is to implement and evaluate active learning strategies to support engineering students in the development of research competences, contributing to the growing need for a closer relationship between research and teaching.

This study was developed using an action research approach. The data were collected through observations, questionnaire and focus group in order to evaluate the active learning strategies used in the context of the study, based on students' perceptions.

The results show that the implementation of active learning strategies, such as research-based learning and think-pair-share enhance the development of research competences, namely critical thinking and written communication. Additionally, this approach enables students to develop further their capstone projects, using the standards demanded in research process.

The study was based mainly on teacher's observation and the participants are undergraduate engineering students enrolled in the course “Scientific Methodology” during 1 academic year.

Two levels of implications can be identified in this study: (1) for teachers' practice, who can adapt the step-by-step descriptions of the implemented approaches and (2) for research, contributing to the discussion about how to explore the teaching-research relationship in undergraduate courses.

The course of “Scientific Methodology” is part of the curricular structure of most undergraduate engineering programs offered by Brazilian Higher Education Institutions, and this study is a contribution for the improvement of knowledge on how this course may be conducted in an effective and engaging way.

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.

This research seeks to provide methodological bases for the identification, documentation and critical reflection of good practices of architectural design in built heritage. These are applied explicitly to the School of Porto architects, which express a high sense of pedagogy and community practice in this field. The methodological approach defines the selection criteria for a georeferenced inventory and the procedures for in-depth analysis of adaptive reuse strategies.

The works included in the inventory were selected according to geographical, chronological, typological, qualitative and quantitative criteria. The cases chosen for in-depth analysis have been studied along four thematic axes to dissect all the intervention processes (previous state, design/construction and final state). This approach is supported by a cross-analysis of different sources (oral, written, graphic) and using drawing as a fundamental research tool.

The research has collected and disseminated up to 150 works by 44 architects, providing a comprehensive portrait of heritage intervention by the School of Porto over the past decades. The selection of 22 buildings for in-depth documentation reveals a particular sensibility toward the cultural values through a case-by-case approach based in deep knowledge of the preexisting context and the introduction of contemporary additions in continuity and harmonious relation with the environmental and sociocultural context.

This work provides a novel methodology suitable for further extension and adaptation to other case studies, as a first contribution to a more comprehensive “Atlas of Architectural Design in Built Heritage” with European case studies. The research aims to introduce new and deeper perspectives on reference works that may constitute pedagogy for the future practice of architects within contextual, inclusive and sustainable approaches.

This paper aims to present a one-shot gesture recognition approach which can be a high-efficient communication channel in human–robot collaboration systems.

This paper applies dynamic time warping (DTW) to align two gesture sequences in temporal domain with a novel frame-wise distance measure which matches local features in spatial domain. Furthermore, a novel and robust bidirectional attention region extraction method is proposed to retain information in both movement and hold phase of a gesture.

The proposed approach is capable of providing efficient one-shot gesture recognition without elaborately designed features. The experiments on a social robot (JiaJia) demonstrate that the proposed approach can be used in a human–robot collaboration system flexibly.

According to previous literature, there are no similar solutions that can achieve an efficient gesture recognition with simple local feature descriptor and combine the advantages of local features with DTW.

The purpose of this paper is to investigate what may influence participation in mobile collaborative consumption (CC). In particular, the authors investigate the effects of individual sociability and psychological antecedents including enjoyment, social connection, altruistic motivation, reputation, trust and embarrassment on the participation intention in this emerging phenomenon, as well as their relationships.

Survey approach was employed to validate the research model.

Hedonic factor, i.e. enjoyment, and social-related factors including altruistic motivation, reputation and embarrassment emerge as important antecedents of participation in mobile CC. On top of these factors, individual sociability plays an important role, by acting as a direct antecedent of the dependent variable, while also influencing their perceived greater altruistic motivation and reputation from participating in the CC. Yet, sociability has no significant effect on perceived enjoyment and embarrassment associated with the activity, suggesting that addressing these factors may encourage individuals with low sociability to participate.

This study taps into mobile technology to support CC in daily consumption activities, and highlights the factors that influence people’s participation in such activities. More importantly, the findings suggest that while it is more likely for individuals with high sociability to participate in this emerging form of social activities, for consumers with low sociability, addressing the enjoyment aspect and embarrassment issue of the activities may nonetheless promote their participation.

The purpose of this paper is to examine the trends, patterns and the impact of cultural and home country macroeconomic influences on Chinese cross-border mergers and acquisitions (CBM&A) as foreign entry strategy for the period of 1998-2011.

Using three regression models, namely, ordinary least squares, the random effects and fixed effects to examine the impact of home country macroeconomic and cultural factors on CBM&A outflows as an entry mode of Chinese firms. The authors check the robustness of the results using system GMM.

The findings suggest that CBM&A as a preferred mode of market entry provides a means for obtaining strategic resources to develop competitive advantages for the Chinese emerging market firms. The regression results indicate that home country macroeconomic and cultural variables, including gross domestic product (GDP), liquidity, interest rates, inflation, acquisitions in resource seeking sectors and cultural distance play an important role in explaining the trends of CBM&A outflows by the Chinese firms.

The results imply that government support to emerging market multinational enterprises (EMEs) to acquire strategic assets and economic policies in the home country play an important role in shaping international expansion behaviour of EMEs through CBM&A. The study demonstrates that outward investments of EMEs are partly a function of the level of economic policies and government support at home. The limitation is that most of the Chinese CBM&A transactions took place in Asia/Pacific locations. Future studies appear warranted if new data become available.

The study demonstrates how the institutions, strategic asset seeking with government support and economic policies in the home country play important role in shaping international expansion behaviour of emerging market enterprises through CBM&A thereby contributing to the political economy literature and institutional theory. More importantly, the study shows that the level of economic policies and development such as GDP, money supply, interest rates, inflation of the home country are important for EME growth in the international market.

Purpose: This chapter focuses on the relations between aging and the perception about the families’ quality of life in a medium-sized Portuguese city. Departing from the descriptions of individuals living with at least one child under 14 years of age, particular emphasis is put on how young adults perceive and incorporate into their speeches the presence and role of non-cohabiting elderly, namely their parents and in-laws, as an expression of the quality of life they experience.

Design/methodology/approach: Data rely on episodic interviews conducted with both men and women with young children (3–14 years old), within a broader sociological research devoted to the study of family rituals. The data collected was analyzed using qualitative techniques of content analysis with the help of NVivo software (QSR). The data is presented recurring to contextualized narratives.

Findings: Data analysis allows to conclude that geography matters in the perception that young adults have when reflecting upon the role of the elderly surrounding them, either their parents or in-laws. The presence and coexistence of generations are perceived as “priceless,” a “fortune,” and a “privilege,” possible in a medium-sized city, where everything is close enough to thicken the informal intergenerational solidarities between grandparents, parents, and grandchildren. Behind the scenes, data, furthermore, discloses unpredictable tensions arising mainly regarding children’s education, rules, and behavior.

Originality/value: This chapter contributes to shed light into the daily life of elderly people who are still independent and active, and the seemingly invisible presence and unimportant role they play in their children and grandchildren’s lives.

Despite the recognition that citizens' perceptions of mega sport events' social impact is critical for the sustainable development of these events and host cities, most previous studies have not taken into consideration how these perceptions may change over time. This study examines citizens' social impact perceptions of the 2016 Rio Olympic Games before and after the event.

Data were collected amongst local residents of Rio de Janeiro pre- and post-event (n = 256). A confirmatory factor analysis (CFA) analysed the psychometric properties of the proposed social impact constructs. Subsequently, a multigroup analysis and latent mean comparisons were conducted to test social impact perceptions pre- and post-event.

The multigroup CFA showed factorial stability of the social impact model in both periods, while the latent mean comparisons revealed significant differences in the dimensions of social experiences, city image and community pride enhancement, public infrastructures and social conflicts. Results indicated that the perception of positive impacts tends to increase, while perceived negative impacts decrease from pre- to post-event.

The social effects of hosting sport mega events result in a short-term change in attitudes towards the local community, leading to a better comprehension on how communities perceive the event's impact on their lives.

In a highly complex mega event such as the Olympic Games, any change may influence residents' perceptions. The findings of this study demonstrate the importance of residents for determining support or opposition in hosting the event, allowing a better understanding of the exchange effects.