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Among the different methodologies used for performance control in precision manufacturing, the measurement of metrological test artefacts becomes very important for the characterization, optimization and performance evaluation of additive manufacturing (AM) systems. The purpose of this study is to design and manufacture several benchmark artefacts to evaluate the accuracy of the selective laser melting (SLM) manufacturing process.

Artefacts consist of different primitive features (planes, cylinders and hemispheres) on sloped planes (0°, 15°, 30°, 45°) and stair-shaped and sloped planes (from 0° to 90°, at 5° intervals), manufactured in 17-4PH stainless steel. The artefacts were measured optically by a structured light scanner to verify the geometric dimensioning and tolerancing of SLM manufacturing.

The results provide design recommendations for precision SLM manufacturing of 17-4PH parts. Regarding geometrical accuracy, it is recommended to avoid surfaces with 45° negative slopes or higher. On the other hand, the material shrinkage effect can be compensated by resizing features according to X and Y direction.

No previous work has been found that evaluates accuracy when printing inwards (pockets) and outwards (pads) geometries at different manufacturing angles using SLM. The proposed artefacts can be used to determine the manufacturing accuracy of different AM systems by resizing to fit the build envelope of the system to evaluate. Analysis of manufactured benchmark artefacts allows to determine rules for the most suitable design of the desired parts.

The purpose of this paper is to provide a new procedure for in-plane compensation of geometric errors that often appear in the layers deposited by an additive manufacturing (AM) process when building a part, regardless of the complexity of the layer geometry.

The procedure is based on comparing the real layer contours to the nominal ones extracted from the STL model of the part. Considering alignment and form deviations, the compensation algorithm generates new compensated contours that match the nominal ones as closely as possible. To assess the compensation effectiveness, two case studies were analysed. In the first case, the parts were not manufactured, but the distortions were simulated using a predictive model. In the second example, the test part was actually manufactured, and the distortions were measured on a coordinate measuring machine.

The geometric deviations detected in both case studies, as evaluated by various quality indicators, reduced significantly after applying the compensation procedure, meaning that the compensated and nominal contours were better matched both in shape and size.

Although large contours showed deviations close to zero, dimensional overcompensation was observed when applied to small contours. The compensation procedure could be enhanced if the applied compensation factor took into account the contour size of the analysed layer and other geometric parameters that could have an influence.

The presented method of compensation is applicable to layers of any shape obtained in any AM process.

This study aims to analyze the effect of the different common post-processes on the geometrical and dimensional accuracy of selective laser melting (SLM) parts.

An artefact has been designed including cubic features formed by planar surfaces orientated according to the machine axes, covering all the X-Y area of the working space. The artefact has been analyzed both geometrically (flatness, parallelism) and dimensionally (sizes, distances) from coordinate measuring machine measurement results at three stages, namely, as-built, after sand-blasting and after stress-relieving heat treatment.

Results from the SLM machine used in this study lead to smaller parts than the nominal ones. This effect depends on the direction of the evaluated dimension of the parts, i.e. X, Y or Z direction and is differently affected by the sandblasting post-process (average erosion ratio of 68, 54 and 9 µm, respectively), being practically unaltered by the HT applied after.

This paper shows the influence, from a geometric and dimensional point of view, of two of the most common post-processes used after producing SLM parts, such as sand-blasting and stress-relieving heat treatment, that have not been considered in previous research.

The lack of geometric and dimensional accuracy of parts produced by additive manufacturing (AM) is directly related to the machine, material and process used. This paper aims to propose a method for the analysis and compensation of machine-related geometric errors applicable to any AM machine, regardless of the manufacturing process and technology used.

For this purpose, an error calculation model inspired by those used in computerized numerical control machines and coordinate measuring machines was developed. The error functions of the model were determined from the position deviations of a set of virtual points that are not sensitive to material and process errors. These points were obtained from the measurement of an ad hoc designed and manufactured master artefact. To validate the model, off-line compensation was applied to both the original designed artefact and an example part.

The geometric deviations in both cases were significantly smaller than those found before applying the geometric compensation. Dimensional enhancements were also achieved on the example part by using a correction parameter available in the three-dimensional printing software, whose value was adjusted from the measurement of the geometrically compensated master artefact.

The errors that persist in the part derive from both material and process. Compensation for these type of errors requires a detailed analysis of the influencing parameters, which will be the subject of future research.

The use of the virtual-point-based error model increases the quality of additively manufactured parts and can be used in any AM system.

The purpose of this paper is propose a citation method for referring to the audio‐visual documents required for television programmes in scientific works.

The existing document typology is checked against television databases available on the internet, and the different units of processing, conservation and diffusion are analysed. The document is structured according to three parameters: whether it has been broadcast; whether it has not been broadcast; and other formats – in order to describe with examples the different citation possibilities of such documents.

This structure tries to be a formal and conceptual response to the ISO 690:1987 Standards. The achieved outcome put forward an effective method to describe these documents in a scope where there is a big gap both for the referenced description and for the research.

This work serves as a base for the production and citation of AV and television works in the media and communication sciences as well as in information science, sociology, history and similar areas.

While researchers have studied the impact of social media on tourist behaviour Milano et al. (2011) and Hays et al. (2013), very few studies have explored the impact of social media on sustainable tourism, and thus, it can be said to be in its “infancy” (Han et al., 2017). There exists a “knowledge gap” not just with tourists but also with researchers, as the issue on sustainable tourism consumption is “rarely investigated directly in tourism researches” or consumer behaviour studies, and there is often discrepancy in literature on the issue (Cohen et al., 2014; Bray et al., 2011). While the potential for social media in promoting sustainable tourism is known considering the use of it for socialisation and knowledge sharing, empirical researches to make in depth enquiry on the same is “rare” (Ali and Frew, 2010; Sarkar et al., 2014). Also, the differences between markets for sustainable tourism amongst different markets needs to explored further (Weber, 2019). The purpose of this study is to fill this gap by proposing a conceptual framework and empirically testing how social media can be used to generate and promote sustainable tourism demand among through evidences from Indian tourists. RQ1: what are the key drivers to use social media by sustainable tourists? RQ2: can social media promotions help sustainable demand generation through spreading awareness and connecting fellow sustainable tourists?

A total of 350 Indian tourists were reached through Google forms distributed through various channels, amongst which 265 responded with a response rate of 75.7%. The data were coded and checked for any outliers and missing values. To avoid any biases, incomplete forms were not counted and after data cleaning, 250 respondents were found to be appropriate with all the responses. Analysis of demographic and travel profile was done through SPSS 22 to check variances in the groups, frequencies and chi square values were calculated. Since this is an exploratory study, the aim was more on prediction rather than model confirmation, thus the technique used and found to be appropriate was partial least squares structural equation modelling (PLS-SEM).

Variances of social media were used in the demographic groups and found that there was no significant difference found as per age and education. Even variation of travel habits was found to be not significant with social media use. It can be seen that social media promotion activities indeed create awareness amongst people about sustainability; creating awareness about sustainability indeed leads to connecting green tourists together. On the other hand, social media promotional activities may not necessarily connect potential green tourists together; awareness positively impacts the generation of sustainable demand is also supported. It can be seen that merely connecting potential green tourists does not necessarily create demand. Social media promotion activities are indeed instrumental in creating a sustainable demand amongst tourist.

This study takes into account the informational and environmental knowledge aspect of sustainable behaviour adoption by green tourists (Swarbrooke and Horner, 2007; Miller, 2003; Chan et al., 2014). This study draws implications based on the behaviour of Indian tourists and thus, the generalisation to other countries may not be as accurate as Indians differ culturally from the world at large. Even though the study involves different age groups, the mean age is of younger Indian tourists, which is also often considered as the most active users of social media and thus likely to be impacted more. Also, it is believed that these younger green consumers who are already inclined towards sustainability tend to seek more information on ethical issues (Finney, 2014). The sample size of the study is very small (n = 250) and was only checked for variation amongst gender and profession; other aspects such as income and employment (Swarbrooke and Horner, 2007; Miller, 2003) have been kept out of the study and thus not included as a part of demographics. More demographic characteristics can be taken into account to study if they play a mediating role in generating sustainable demand as a part of the analysis of this conceptual framework proposed.

Internet allows users to obtain information about products and brands to its users through various social media such as blogs, forums, wikis content sharing, etc. (Hennig-Thurau and Walsh, 2003; Reilly and Weirup, 2010). Strategies can thus be formulated to target sustainable tourists with sustainable destinations and amenities, so as to attract those tourists who appreciate and commit to the cause of sustainability (López-Sánchez and Pulido-Fernández, 2016). Using social media as a promotion tool can help in educating customers (Xiang and Gretzel, 2010) on the various sustainable tourism services they intend to offer, as the results supports the use of social media promotion for generating sustainable demand amongst the tourists. Also, the sustainable tourism providers can make use of promotional activities focussing on building online pro environmental tourist-based communities using the user generated contents which can positively lead to adoption of collective social behaviour and sustainable practices (Han et al., 2017). Specifically, the use of short interactive messages can be used for social media promotions, so as to increase “organisation prominence” amongst the green target groups online (Strähle and Gräff, 2017). While it was noted that different markets react differently to the idea of sustainability, and thus, different markets need to be explored deeper (Weber, 2019); this study attempts to provide a perspective of Indian tourists which not just adds to the literature on Indian tourist behaviour but also provides a viewpoint of the Asian tourists. It also enriches the existing literature on the use of AIDA model for services and tourism specifically which as a theoretical base is unexplored.

The study adds to the rising interest in understanding the behavioural changes in tourists (Hall, 2016) and provides insights on “the versatility of the topic of relationship between sustainable tourism and marketing” (Font and McCabe, 2017). While ethical consumption is essential to preserve resources, the study of this area of consumer behaviour is “under examined”, as majority studies focus on products, very few studies elucidate on encouraging it through social marketing (Newholm and Shaw, 2007). Thus, this study attempts to fill the gap in the literature by proposing a framework for generating sustainable demand amongst tourists so that they are inclined socially and sustainably both through the use of social media. It is often noted that tourists are unwilling to change their travel behaviour as a result of lack of awareness or due to hesitance of sacrificing (Juvan and Dolnicar, 2014; Miller et al., 2010). This study provides empirical evidence that supports the awareness of sustainability as a means of generating sustainable demand amongst tourists. Knowledge regarding tourism demand helps in the further development of tourism products and its marketing initiatives (Weber, 2019). Thus, it allows tourism players to understand that Indian tourists are open to sustainable tourist practices if enough information is provided to them.

The purpose of this paper is to visualize the inter‐university and international collaboration networks generated by Spanish universities based on the co‐authorship of scientific articles.

The approach takes the form of formulation based on a bibliometric analysis of Spanish university production from 2000 to 2004 as contained in Web of Science databases, applying social network visualization techniques. The co‐authorship data used were extracted with the total counting method from a database containing 100,710 papers.

Spanish inter‐university collaboration patterns appear to be influenced by both geographic proximity and administrative and political affiliation. Inter‐regional co‐authorship encompasses regional sub‐networks whose spatial scope conforms rather closely with Spanish geopolitical divisions. Papers involving international collaboration are written primarily with European Union and North and Latin American researchers. Greater visibility is attained with international co‐authorship than with any other type of collaboration studied.

Impact was measured in terms of journals rather than each individual paper. The co‐authorship data were taken from the Web of Knowledge and were not compared with data from other databases.

The data obtained in the paper may provide guidance for public policy makers seeking to enhance and intensify the internationalization of scientific production in Spanish universities.

The Spanish university system is in the midst of profound structural change. This is the first paper to describe Spanish university collaboration networks using social network visualization techniques, covering an area not previously addressed.