Discontinuity spacing analysis in rock masses using 3D point clouds

The complete characterization of rock masses implies the acquisition of information of both, the materials which compose the rock mass and the discontinuities which divide the outcrop. Recent advances in the use of remote sensing techniques – such as Light Detection and Ranging (LiDAR) – allow the accurate and dense acquisition of 3D information that can be used for the characterization of discontinuities. This work presents a novel methodology which allows the calculation of the normal spacing of persistent and non-persistent discontinuity sets using 3D point cloud datasets considering the three dimensional relationships between clusters. This approach requires that the 3D dataset has been previously classified. This implies that discontinuity sets are previously extracted, every single point is labeled with its corresponding discontinuity set and every exposed planar surface is analytically calculated. Then, for each discontinuity set the method calculates the normal spacing between an exposed plane and its nearest one considering 3D space relationship. This link between planes is obtained calculating for every point its nearest point member of the same discontinuity set, which provides its nearest plane. This allows calculating the normal spacing for every plane. Finally, the normal spacing is calculated as the mean value of all the normal spacings for each discontinuity set. The methodology is validated through three cases of study using synthetic data and 3D laser scanning datasets. The first case illustrates the fundamentals and the performance of the proposed methodology. The second and the third cases of study correspond to two rock slopes for which datasets were acquired using a 3D laser scanner. The second case study has shown that results obtained from the traditional and the proposed approaches are reasonably similar. Nevertheless, a discrepancy between both approaches has been found when the exposed planes members of a discontinuity set were hard to identify and when the planes pairing was difficult to establish during the fieldwork campaign. The third case study also has evidenced that when the number of identified exposed planes is high, the calculated normal spacing using the proposed approach is minor than those using the traditional approach.

Incidencia e influencia de las políticas en el cambio social: responsabilidad de las trabajadoras sociales e implicaciones para su educación teórica y práctica

La incidencia en las políticas sociales es una importante función profesional de las trabajadoras sociales que precisa ser integrada en la educación teórica y práctica en Trabajo Social. Este artículo indaga sobre los fundamentos de esta función de incidencia en los cambios sociales promoviendo políticas sociales que reconozcan los derechos humanos. Partiendo de los referentes internacionales del trabajo social, se analiza el caso de España teniendo en cuenta los códigos deontológicos, los planes de estudio en Trabajo Social, la práctica profesional y los nuevos Grados en Trabajo Social. Se concluye planteando interrogantes sobre el grado de responsabilidad y de implicación de las universidades y Colegios profesionales en coherencia con los principios y valores del Trabajo Social.

Open access, repositorios, directorios de repositorios y open licenses

Este trabajo aborda el tema del acceso abierto (open access) de la literatura científica. Se analizan las declaraciones sobre las que se basan sus cimientos y las estrategias existentes para la difusión del conocimiento. Así mismo, se tratan las iniciativas que colaboran con este fin: los repositorios, los directorios de repositorios de acceso abierto y las licencias abiertas (open licenses). Por último, se pone de manifiesto la relación que existe entre el movimiento de acceso abierto y las iniciativas relacionadas con los recursos educativos abiertos.

Is financial instability male-driven? Gender and cognitive skills in experimental asset markets

The hypothesis that price stability would reliably increase with the fraction of women operating in financial markets has been frequently suggested in policy discussions. To test this hypothesis we conducted 10 male-only, 10 female-only and 10 mixed-gender experimental asset markets, and compared the effects of gender composition, confidence, risk attitude and cognitive skills. Male and female markets have comparable volatility and deviations from fundamentals, whereas mixed-gender markets are substantially more stable. On the other hand, higher average cognitive skills of the group are associated with reduced market volatility. Individual-level analysis shows that subjects with higher cognitive skills trade at prices closer to fundamental values and earn significantly higher profits; similarly, mixed markets exhibit lower mispricing, particularly for traders with lower cognitive skills. Our results are demonstrated to hold in other experimental asset market studies, suggesting that a mixed-gender composition reduces mispricing across different types of asset markets.