Describing national science and technology systems through a multivariate approach: country participation in the 6th Framework Programmes

The objective of this work is to describe the distribution of different types of participating organizations in the health thematic area of the 6th Framework Programme. A total of 2132 different organizations were classified according to four types and then grouped by country. A Principal Component Analysis (PCA) was carried out on the percentage of funding obtained by each type of organization. Results show a countries map plotted around the “private” and “public” principal components. It is observed that there are countries which research is basically performed by government research centres, while others are supported in the university activity. We conclude that the PCA is a suitable method to plot the distribution of research organizations by country and the results could be used as a tool for theoretical studies about the scientific activity in a country.     

Synoptic weather patterns associated with carbon dioxide levels in Northern Spain

Measurements of atmospheric carbon dioxide, CO₂, were continuously carried out in the upper Spanish plateau over a three-year campaign, 2003-2005. Temporal CO₂ variations were examined. The results allow identification of the average data representative of background conditions, 382.9 ppm, with values ranging from 346.2 to 502.5 ppm. The weekly cycle evidences a difference of 0.2 ppm between weekday and weekend residuals, with levels increasing during the week. Seasonal variation in monthly means was inferred, the largest peak in appearing in spring, about 388 ppm. High values were also recorded in autumn, particularly in 2005 with an additional 5 ppm. By contrast, minimum values were obtained in July, between 374 and 379 ppm.A link between CO₂ concentrations and meteorological variables is explored. Analysis of surface wind speed intervals shows that low winds are the most frequent and are linked to the highest concentrations, around 395 ppm at night and in spring. CO₂ concentrations drop significantly for the 3.1-5.3 m s^− 1 interval from which steady levels, around 378 ppm except in autumn, were observed. If different temperature intervals are considered, the 10-15 °C interval establishes the boundary between the extreme mean CO₂ levels, except for winter, 5-10 °C. The mean associated values ranged between 376.0 and 390.4 ppm, with a greater contrast in spring, 12.8 ppm.Finally, the relation between synoptic-scale atmospheric transport patterns and maximum CO₂ concentrations was also examined. The highest values occur in spring with some quite frequent synoptic situations: continental ridges, troughs to the west, interactions of the two and Atlantic ridges.     

An analysis of the temperature field of the workpiece in dry continuous grinding

The recent model for heat transfer during intermittent grinding described in Skuratov, Ratis, Selezneva, Pérez, Fernández de Córdoba and Urchueguía (Appl Math Model 31:1039–1047, 2007) is considered. This model is particularized to the case of continuous dry grinding, where an alternative solution is obtained in the steady state. This alternative solution is analytically equivalent to the well-known formula of Jaeger (Proc R Soc NSW 76:204–224, 1942) for the steady–state temperature field created by an infinite moving source of heat and proves to be very useful for evaluating the maximum point of the temperature.     

Optimising detection of acidification kinetics diversity in Lactococcus lactis subsp. lactis using SDS‐PAGE protein fingerprinting as screening method

Cell‐free extracts from 157 Lactococcus lactis strains isolated from Artisan cheese were screened by protein fingerprinting previous to their technological characterisation. The strains were classified according to their electrophoretic patterns into five groups. A set of strains representing the different clusters were selected to study their acidifying activity in milk. Time and rate feature points, as well as the shape of the acidification curves, resulted in six different fermentation kinetics, mostly consistent with the electrophoretic groups. Thus, selection of native strains as starter cultures based on their acidifying activity could be optimised by protein fingerprinting.     

Robust Fitting of Ellipsoids by Separating Interior and Exterior Points During Optimization

Fitting geometric or algebraic surfaces to 3D data is a pervasive problem in many fields of science and engineering. In particular, ellipsoids are some of the most employed features in computer graphics and sensor calibrations. They are also useful in pattern recognition, computer vision, body detection and electronic device design. Standard ellipsoid fitting techniques to solve this problem involve the minimization of squared errors. However, most of these procedures are sensitive to noise. Here, we propose a method based on the minimization of absolute errors. Although our algorithm is iterative, an adaptive step size is used to achieve a faster convergence. This leads to a substantial improvement in robustness against outlier data. The proposal is demonstrated with several computational examples which comprise synthetic data and real data from a 3D scanner and a stereo camera.     

Empirical study of a sequence of access to Internet use in Ecuador

Ecuador is a country that represents the efforts that a few countries in the Latin American and the Caribbean region are making on infrastructures, regulations and policies that are favorable towards the use of the Internet. However, although the digital divide in its most basic form (physical access and use) is closing with respect to developed countries, a new, more complex digital divide is moving forward, and is related to the socio-economic advantages of the Internet. This study, which used a random sample stratified by provinces and which comprised 3754 respondents representing the secondary school students in Ecuador, had as objectives: (a) to verify the relationship and sequence among the different levels to access the Internet found on secondary school students; and (b) to verify to what degree the student’s family status influenced the different levels of Internet access. Through the empirical analysis of a structural model, the results showed a sequence between the relationships found among the different levels of Internet access, as well as the cumulative effect of the technical resources and levels of digital literacy on the academic use of the Internet. Likewise, it was observed that the influence of the student’s family status lost strength as the level of Internet access increased.     

Mechanical behavior and failure analysis of recycled polymers by use of miniature punch specimens

In today's society, recycling is a priority, and using recycled materials to obtain new 100% reusable materials is an important aspect of some manufacturing sectors. Clearly, the mechanical properties of these new materials can vary considerably from the original material, so it is necessary to carry out a complete mechanical characterization to know its behavior for both standard specimens and final components. One of the common drawbacks is the inability to extract standard size specimens from a final component with a reduced size. In this paper, the use of the small punch test is proposed as a means of solving this problem. At present, this test is used for estimating mechanical properties in those cases when there is not a sufficient amount of material to perform standard tests. The main purpose of this paper is to analyse the feasibility of using miniature punch specimens for the mechanical characterization of recycled polymers. The results are compared with those obtained from standard uniaxial tensile specimens, and a corresponding correlation between the two tests is established. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42911.