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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.

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.

This study aims to assess the potency and dose of Δ-9-Tetrahidrocannabinol (THC) and Cannabidiol (CBD) in cannabis joints. This will enable better estimates of the degree of exposure in a user and contribute towards a better understanding of potential harmful effects.

Analysis of intact joints confiscated by law enforcement on the street in the autonomous region of Castilla y León (Spain) during the years 2017–2019.

This study analysed THC, CBN and CBD in marijuana joints (N = 744). Joints contain cannabis and tobacco (N = 729), had a median net weight 0.69 g (IQR = 0.28); concentration THC median was 6.30%(IQR = 4.51) and THC median dose 42 mg (IQR = 32.75). A total of 35.5% mixed joints contained CBN – median percentage 0.61% (IQR = 0.51). CBD was detected 10.3% of mixed joints – median percentage 0.13% (IQR = 0.12) and median dose 1 mg (IQR = 0.92). CBD/THC ratio presented median value of 0.02 (IQR = 0.02). The samples analysed comprised pure cannabis joints (N = 15), with THC median 11.86% (IWR = 6.30) or median dose of 118 mg.

The study found high values for concentration and dose of THC and CBD in cannabis joints, warning of high exposures for the user and associated potential consequences. The results obtained contribute new perspectives on the definition of a standard cannabis unit.

The main objective of this work is to design a statistical multiple regression model that helps to empirically explain the impact of economic incentives, management style, emotional health and research activities on university professors in northern Mexico and their perception of happiness.

In this research, the authors analysed the correlation between happiness perception and four independent variables divided into two dimensions: 1. individual dimensions: emotional health and research activities and 2. organisational dimensions: economic incentives and management styles. A questionnaire was developed, tested and analysed for this matter. The authors applied this instrument to 384 university professors of both genders among 1301 in the region.

Using correlational analysis, the authors confirm a strong and statically significant relationship between all variables. It is also no evidence of multicollinearity. Finally, by applying multiple regression analysis, it was accepted that all independent variables have significance in explaining the emergence of personal happiness (R2 = 42%). Finally, the predictive equation presents possible results with values that confirm the effectiveness of the theoretical model. Results indicate that happiness perception is related to independent variables, with economic incentives being the most vital relationship.

This study's limitations are that the novel perspective of the explanatory variables of economic incentives, emotional health, management style and research activities needs additional confirmatory studies. Therefore, the authors need to perform studies with new explanatory perspectives. Another limitation of the study may be considering a cross-sectional and not a longitudinal model. This study considered it more appropriate to analyse the explanatory variables that influence and are the outcome of happiness perception for the data collected. Finally, it is essential to highlight that this research has been conducted in an underdeveloped country. Thus, it should consider conducting subsequent confirmatory studies in similar settings and other types of economies, such as in a developed country.

This paper explains the relevance of two-dimensional activities in the happiness perception of professors. As other studies mention, productivity is correlated to happiness, and production outcomes could be improved if the schools implement policies to promote this perception. Happiness could be a solid strategy to improve academic outcomes, and the results propose several actions to achieve this goal.

This paper addresses an important activity of professors from a perspective of happiness perception. Thus, putting the professor as the leading relevant agent in schools, the authors propose a multivariate analysis of the outcomes of professors' jobs. Both the schools and the professors have their own goals at their own levels. If policies are created based on persons, in this case, professors, to improve organizational goals, then it might profoundly impact social actions inside the schools.

This paper increases the literature on happiness perception studies and proposes the examination of the relationship between perceived personal happiness and dimensions that influence this perception; these are from two kinds: 1. individual dimensions: emotional health and research activities and 2. organisational dimensions: economic incentives and management styles, which is an original approach and open discussion to further new approaches to this study.

I evaluate how the tax reform of 2012 reduced informality in Colombia both theoretically and empirically. Theoretically, I develop a labor market model and obtain simulations indicating that the reform should reduce informality significantly. Empirically, I obtain difference-in-difference estimates from two household surveys. Estimates from the repeated cross-sections data indicate small, short-term effects and large long-term effects. Estimates from the household survey panel data are in line with these results. I also simulate difference-in-difference estimates with different combinations of changes in payroll taxes and enforcement indicating that large improvements would have been needed to obtain the corresponding econometric estimates.

The present research aims to study the correlations among organizational climate, academic satisfaction and organizational commitment as factors that influence happiness at work by applying a structural equation model to Spanish National Police cadets.

A descriptive, quantitative, correlational, exploratory and cross-sectional empirical study was carried out. A measurement instrument was applied to a target population of 397 student-inspectors enrolled for the 2018–2020 academic year on the executive scale at the National Police School (EPN) in Spain. A sample of 190 surveys was obtained, of which 33 were open competition, 52 were competitive examinations and 105 were selective seniority.

Structural equation modeling shows that academic satisfaction, organizational climate and practical organizational commitment are recommended variables for assessing happiness within organizations. On the other hand, there is a bit of a positive relationship between happiness and practical organizational commitment. The same is not true for the parameters of academic satisfaction and organizational climate.

This study fills a gap in the literature on the analysis of governance models in public administration. This is particularly relevant in professions that require a high degree of engagement with citizens, such as police officers. According to the authors’ knowledge, this study is one of the first works to analyze corporate governance in police cadet schools in Spain under the happiness management approach. It contributes by offering a better understanding of the psychosocial variables that affect the existence of good governance.

This study provides a new look at the late 19th-century university issue in Spain. Loss of self-government among universities and the state’s centralization brought a conflict between science and religion to the fore in the process of the secularization of knowledge.

We first delve into the anti-Darwinian framework associated with the scientific professionalization process, focusing on the case of the jurist Antonio Hernández Fajarnés (1851–1909). Secondly, we study the idea of the university that emerged from the Ateneo de Madrid, analyzing key speeches from the jurist Francisco Fernández de Henestrosa (1855–s.d.) given in 1887/88 and from the pharmacist José Rodríguez Carracido (1856–1928).

The study concludes that the Restoration Era in Spain was characterized by a generalized desire – shared by neo-Scholastics, conservatives and liberal rationalists – to improve the public university system. In this context, French influence was no doubt decisive; however, the Humboldtian university idea had already begun to have notable influence.

This article analyzes sources yet unknown to international research, such as the Ateneo de Madrid debates and Spanish university rectors’ inaugural speeches. It opens up a critical examination of the so-called displacement of educational principles in Spain toward a state-centered system of doctrinal moderantismo as opposed to the nation-centered system of the Cádiz liberalism. At the same time, it identifies key pockets of resistance relative to Spanish university transformation toward increased methodological secularization.