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This paper aims to study the interfacial and interlayer bonding of Polylactic acid parts manufactured by fused deposition modelling. Different layer thicknesses are analysed in the manufacture of these pieces and the lack of material associated with this parameter is verified. The influence of the immersion of these parts in different solvents is also studied, as they are increasingly used in the improvement of the surface finish. Tomography results are also obtained in which the increase in density of the parts subjected to these treatments is demonstrated.

The material used in this study is a 1.75-mm diameter polylactic acid (PLA) filament from fused filament fusion world. Monolayer and multilayer samples have been manufactured. The manufactured parts were subjected to solvent immersion for a period of 60 s. The solvents used are chloroform (CHCl3), dichloromethane (CH2Cl2), tetrahydrofuran (C4H8O) and ethyl acetate (C4H8O2). The pieces were then dried for 48 h. The interior of the samples was evaluated by two techniques: microscopy and tomography.

With this study, it has been observed that the thickness of the layer affects the porosity interfacial to a greater extent than in the interlayer, causing the increase in porosity as this thickness is increased.The impact of different chemical treatments (immersions in different solvents) on the internal quality of the parts has been evaluated. All the solvents analysed soften the surface as they cause the softening of the material and its possible redistribution. In the interior, however, they affect in a lighter way. The retention of solvents in the porosity of the pieces is also checked, especially pronounced in the areas close to the surface. Finally, changes are observed in the density of the pieces, related to the partial crystallization of the samples.

All that has been studied shows that the application of chemical post-processes not only affects the surface texture of the parts, or the less studied mechanical properties, but also affects the interfacial union of the parts in a very different way. This is the first study carried out on this aspect with polylactic acid (PLA) and post-processing methods.

The evaluation of novel materials such as the acrylonitrile styrene acrylate (ASA) for tribological and mechanical conditions can provide a structural protection against the environmental and wear effects that results in the long-term integrity of the 3 D printed parts. Results of the experimental stage are intended to identify the influence of the printing conditions on the functional characteristics of ASA parts that results in variations of the friction coefficient, wear rate and tensile response. In addition, this study aims to highlight the relevance of printing parameters to avoid the use of chemical post-processing stages, increasing the performance and sustainability of the process.

In this research, an evaluation of the influence of printing parameters of layer thickness and temperature on the mechanical and tribological response have been carried out for ASA specimens manufactured by fused filament fabrication technology. For this purpose, a range of three different values of thickness of fused layer and three different printing temperatures were combined in the manufacturing process of tests samples. Mechanical behavior of the printed parts was evaluated by standard tensile tests, and friction forces were measured by pin-on-disk tribological tests against steel spheres.

Higher layer thickness of the printed parts shows lower resistance to tribological wear effects; in terms of friction coefficient and wear rate, this type of parts also presents lower tensile strength. It has been detected that mechanical and tribological behavior is highly related to the micro-geometrical characteristics of the printed surfaces, which can be controlled by the manufacturing parameters. Under this consideration, a reduction in the coefficient of friction near to 65% in the average value was obtained through the variation of the layer thickness of printed surfaces.

This research aims to fill a gap in the scientific literature about the use of specific additive manufacturing materials under dynamic contact. This paper is mainly focused on the influence of the manufacturing parameters on the tribological and mechanical behavior of a weather resistant polymer (ASA).

The purpose of this study was to evaluate the influence of knowledge management (KM) drivers on perceived KM results in a public higher education institution. A structured theoretical model based on leadership, people, processes, knowledge processes, technology, learning and KM results was developed and tested.

A survey was conducted with the employees of a public higher education institution where an administrative reform was initiated. A valid sample of 257 respondents was obtained. The data were obtained from the application of a structured questionnaire based on the KM drivers and their results. A five-point Likert-type scale was used to measure respondents' answers. The main data analysis technique was structural equation modeling.

The results indicate knowledge processes, leadership and people factors have a positive and significant impact on KM results. On the other hand, organizational processes, technology and learning factors were not significant. However, the service length of servants in the institution influences the perception of knowledge drivers.

Public institutions should be attentive to people with more time of service because they may have difficulties with technological advances, reorganization of processes and adaptation to new ways of sharing knowledge.

This study advances on the analysis of KM results in the public sector and tests the moderation effect of time of service.

The purpose of this investigation is to analyze information on the web and its preservation as the digital heritage of events related to climate change and the environment in Portugal and Brazil, thus contributing to web preservation in the Ibero-American context.

A theoretical and applied investigation using mixed methods to collect and analyze qualitative and quantitative data from three sources: the Internet Archive and the public collection of Archive-It, the Portuguese web archive, and a selection from collections compiled by a research group (UFRGS) on web archiving and digital archiving in Brazil.

Web archive initiatives started in 1996; however, over the years collections have narrowed from nationally relevant themes to specialized thematic niches. The theme “climate change” has had an increasing impact on scientific and mainstream discussion in the 2000s, and by 2010 the over-arching theme became focused on digital preservation of web content, as demonstrated in this study. Failure to preserve data can lead to a rapid loss of climate change information, due to the inherent ephemerality of the web.

The paper demonstrates the relevance of preserving web content on climate change by showing what has been preserved to date and what will need to be preserved in the future.

The purpose of this paper is to analyse the potential benefits of identifying homogeneous territorial units of the urban-tourism space at a local scale.

The territory is an essential variable for designing tourist activities adapted to the characteristics of each urban-tourism space. However, your consideration presents a series of problems, including the lack of alphanumeric, microscale, georeferenced statistical information. The territorial segmentation of the tourist accommodations supply is approached as a methodology, a technique and an instrument that can be used to apply marketing strategies in coastal tourism areas.

One of the most important results is that territorial segmentation is a methodology and technique that can mitigate this issue because it is well-suited to defining spatial patterns of tourist behaviour through the delimitation of territorial units that have a certain degree of homogeneity.

The idea of territorial segmentation is the ideal technique for understanding tourists and their behaviour in the territory by integrating all the variables that intervene in a trip, the different aspects of the destination and data regarding tourist behaviour, allowing them to be understood at the greatest level of territorial disaggregation and making it a good tool for public and private actors, capable of facilitating intelligent decisions in strategic territorial planning and in defining the marketing approach of tourism companies.

The study seeks to analyze the influence of sensory experience on perceived environmental sustainability and word-of-mouth (WOM) of tourists and residents. The study also tests the moderation effect of satisfaction on the relationship between perceived environmental sustainability and WOM.

The study was conducted in Sikkim, a state in the northeastern part of India, which is regarded as the world's first organic state. The study was done in two phases. In the first phase, the data were collected from the tourists. And in the second phase, data were collected from the residents. A structured questionnaire was distributed to 700 tourists and residents in Sikkim. Out of these only 484 responses were considered for the study. Multivariate analyses were done using SPSS software and packages like Process Macro, and Amos to test the hypotheses.

The findings of the study indicated that sensory experience significantly influences perceived environmental sustainability and WOM. The study model fit with GFI = 0.955, CFI = 0.946 NFI = 0.929 and RMSEA = 0.07. The findings also indicate that satisfaction moderates the relation between sensory experience and word-of-mouth with a p value = 0.018.

The study was conducted in Sikkim and it used a convenience sampling method. Therefore, the study cannot be generalized.

An emphasis on building an organic brand image can positively impact the local community. A study of this kind will encourage the community to work toward sustainable development.

The study is unique as it explores the evaluation of destination environmental sustainability. And it is one of the first to test the impact of satisfaction in the relationship between the independent and dependent variables in the context of the tourism experience.

The purpose of this paper is to conduct an inductive case study to understand how the opportunity creation process leads to integration.

It examines four cases of immigrant entrepreneurs of Cameroonian, Lebanese, Mexican and Assyrian origins who founded their businesses in Sweden. The study relies on process-oriented theory building and develops an inductive model of integration as an opportunity creation process.

The suggested model shows immigrants’ acculturation into the host society via three successive phases: breaking-ice, breaking-in and breaking-out. In the breaking-ice phase, immigrants trigger entrepreneurial ideas to overcome the disadvantages that they face as immigrants in the host country. In the breaking-in phase, immigrants articulate their entrepreneurial ideas by bonding with the ethnic community. In the breaking-out phase, the immigrants reorient their entrepreneurial ideas by desegregating them locally. The paper concludes by elaborating theoretical and practical implications of the research.

Immigrants act when they are socially excluded and discriminated in the labor market by developing business ideas and becoming entrepreneurs. By practicing the new language and accommodating native customers’ preferences, immigrants reorient their entrepreneurial ideas. The immigrants tailor their ideas to suit their new customers by strengthening their sense of belonging to the local community.