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The performance of the parts obtained by fused filament fabrication (FFF) is strongly dependent on the extent of bonding between adjacent filaments developing during the deposition stage. Bonding depends on the properties of the polymer material and is controlled by the temperature of the filaments when they come into contact, as well as by the time required for molecular diffusion. In turn, the temperature of the filaments is influenced by the set of operating conditions being used for printing. This paper aims at predicting the degree of bonding of realistic 3D printed parts, taking into consideration the various contacts arising during its fabrication, and the printing conditions selected.

A computational thermal model of filament cooling and bonding that was previously developed by the authors is extended here, to be able to predict the influence of the build orientation of 3D printed parts on bonding. The quality of a part taken as a case study is then assessed in terms of the degree of bonding, i.e. the percentage of volume exhibiting satisfactory bonding between contiguous filaments.

The complexity of the heat transfer arising from the changes in the thermal boundary conditions during deposition and cooling is well demonstrated for a case study involving a realistic 3D part. Both extrusion and build chamber temperature are major process parameters.

The results obtained can be used as practical guidance towards defining printing strategies for 3D printing using FFF. Also, the model developed could be directly applied for the selection of adequate printing conditions.

Questioning gender is about taking an active, critical role in the technological design of our daily behaviour. It is a deconstruction of the oppositions that exist in the discourses of Ambient Intelligence designers, the ICT industry and computer scientists. What underlies the assumption that Ambient Intelligence will, by disappearing into our environment, bring humans both an easy and entertaining life? The gender perspective can uncover power relations within the promotion and realisation of Ambient Intelligence that satisfy an obvious wish for a technological heaven. The deconstruction of the promise of progress and a better life reveals what is overvalued, what is undervalued and what is ignored. This paper is a deconstruction of the view, currently prevalent in the discourses of Ambient Intelligence; a view of humans and the way they live. A view that will influence the way women and men will be allowed to construct their lives.

The study deals with the problems of development of critical thinking among university students, its connection with motivation for learning and academic achievements of students. The purpose of the study is to define the relationship between academic motivation and critical thinking.

The study involved a survey based on the academic motivation scale. A total of 520 students from four universities in Russia and one Bulgaria University were interviewed.

The analysis of the questionnaires showed that among the students surveyed the types of motivation contributing to self-development and analysis predominate, namely self-development, cognitive, achievement and self-esteem motivation. The null hypothesis of the study that there was no difference between the average score of the critical thinking test (Watson Glaser Critical Thinking Appraisal, WGCTA) for total sample and the results of students with dominant types of academic motivation that contribute to critical thinking was rejected.

It was revealed that academic motivation has a notable effect on critical thinking and can become a predictor of its development. Several ways have been proposed to track and help students with low academic motivation: regular testing, identification of students with amotivation and strong extrinsic motivation, and psychological support for such students.

This study evaluates the knowledge structure of medical tourism within the geographical context of South East Asia. This region is one of the growing economic powerhouses in the world, and tourism activities have contributed a lot to its advancement.

Applying a science mapping technique using bibliometric analysis, the current and emerging themes and future trends are analyzed using bibliographic coupling and co-word analysis.

Findings show that current trends produced four themes: Fundamentals of medical tourism in Southeast Asia, determinants of tourist medical tourism visits, quality of medical and health service in Southeast Asia and impact of medical tourism on national economic growth. The future trends also produced four themes related to navigating excellence in medical tourism, medical tourism and economic growth, service quality in medical tourism services and accredited destinations in the globalized era of medical tourism.

This study is relevant to all stakeholders, operators and local communities in Southeast Asia tourism destinations to provide the best medical tourism with the best quality service and technologies.

This study fills the gap by performing a bibliometric approach to reviewing medical tourism in Southeast Asia using a science mapping technique. Crucial themes are produced through topological and temporal streams that provide critical insight for future developments in medical tourism in the region.

The paper seeks to bridge the already familiar benefits of 3D printing (3DP) to the rehabilitation of cultural heritage, still based on the use of complex and expensive handcrafted techniques and scarce materials.

A compilation of different information on frequent anomalies in cultural heritage buildings and commonly used materials is conducted; subsequently, some innovative techniques used in the construction sector (3DP and 3D scanning) are addressed, as well as some case studies related to the rehabilitation of cultural heritage building elements, leading to a reflection on the opportunities and challenges of this application within these types of buildings.

The compilation of information summarised in the paper provided a clear reflection on the great potential of 3DP for cultural heritage rehabilitation, requiring the development of new mixtures (lime mortars, for example) compatible with the existing surface and, eventually, incorporating some residues that may improve interesting properties; the design of different extruders, compatible with the new mixtures developed and the articulation of 3D printers with the available mapping tools (photogrammetry and laser scanning) to reproduce the component as accurately as possible.

This paper sets the path for a new application of 3DP in construction, namely in the field of cultural heritage rehabilitation, by identifying some key opportunities, challenges and for designing the process flow associated with the different technologies involved.

In collaborative settings, such as research and development projects, obtaining the maximum benefit from knowledge management systems depends on the ability of the different partners to understand the conceptualisation underlying the system’s knowledge organisation. This paper aims to show how information/knowledge organisation in a multi-organisation project can be made more effective if the domain experts are involved in the specification of the systems semantic structure. A particular aspect is further studied: the role of conceptual relations in the process of collaborative development of such structures.

An action-research approach was adopted, framed by a socio-semantic stance. A collaborative conceptual modelling platform was used to support the members of a research and development project in the process of developing a lightweight ontology aiming at reorganising all the project information in a wiki system. Data collection was carried out by means of participant observation, interviews and a questionnaire.

The approach to solve the content organisation problem revealed to be effective both in the result and the process. It resulted in a better-organised system, enabling more efficient project information retrieval. The collaborative development of the lightweight ontology embodied, in fact, a learning process, leading to a shared conceptualisation. The research results point to the importance of the elicitation of conceptual relations for structuring the project’s knowledge. These results are important for the design of methods and tools to support the collaborative development of conceptual models.

This paper studies the social process leading to a shared conceptualisation, a subject that has not been sufficiently researched. This case study provides evidence about the importance of the early phases of the construction of ontologies, mainly if domain experts are deeply involved, supported by appropriated tools and guided by well-structured processes.

Portugal is a country with one of the highest seafood consumption per capita in the world. The purpose of this paper is to understand the Portuguese knowledge and attitudes towards seafood and relate it to consumers’ environmental conscious.

Using an internet-based survey the authors investigated the relation of socio-demographic variables to consumption frequency and how knowledge about seafood is associated with interest in different information when purchasing seafood products.

Results demonstrate consumption of a high diversity of species. Tuna and cod are the top species related to convenience and food traditions. There is a preference to consume seafood mostly at home and prepared grilled. Differences between higher and lower knowledgeable consumers’ related to seafood, show that the first ones have a more diversified use of species and high prevalence of small pelagic fish.

The findings are influenced by the sample obtained, which over-represents well-educated and higher income people. Moreover the self-reported consumption can be biased by individuals own perceptions and different seafood products. Better estimations of consumption frequency could result from asking more detailed information, as such as by species or meal occasions.

Portuguese consumers have high knowledge about seafood but it is not necessarily related to sustainable choices. To help in sustainable seafood choices it might be more effective to promote existing habits based on Portuguese traditions that still are good alternatives for the marine environment.

A higher consumer’s knowledge does not necessarily mean more sustainability.

The purpose of this paper is to show a standard RBC model, when augmented with a VAT evasion channel, where evasion depends on the consumption tax rate, can produce a hump-shaped consumption-Laffer curve.

The methodology is in the spirit of modern quantitative macroeconomic literature.

The model with VAT evasion can generate a peaking consumption tax revenue curve, which is a little discussed result in the taxation literature.

The paper contributes to the public finance literature by providing evidence for the importance of the evasion mechanism, while at the same time adding to the debate about the existence of a peak tax rate for consumption tax revenue.

Contrary to popular belief, raising VAT rate as a cheap way (being a tax on demand) to finance government expenditure, is still not a free lunch, and raising the rate, especially in a country with substantial VAT evasion, quickly leads to a drop in the revenue associated with that category.

This is the first study that provides a tractable model of VAT evasion, and a setup where consumption tax revenue curve is peaking.

The inherent linkages between climate and the habitability of the Earth are increasingly well recognized, and a convention could help to ensure that conserving the environment and developing the economy in the future must go hand in hand. Due to growing environmental concern, the United Nations General Assembly has set into motion an international negotiating process for a framework convention on climate change. One of the specific tasks in these negotiations is how to share the duties in reducing climate relevant gases, particularly carbon dioxide, between the industrial and the developing countries. The respective proposals could be among the most far‐reaching ever for socio‐economic development, indeed for global security and survival itself. While the negotiations will be about climate and protection of the atmosphere, they could lead to fundamental changes in energy, forestry, transport and technology policies, and to future development pathways with low greenhouse gas emissions. Addresses some of these aspects of a climate convention and a respective CO⊂2‐agreement, the Houston Protocol.