Statistical and spatial analysis of landslide susceptibility maps with different classification systems

The final publication is available at Springer via http://dx.doi.org/10.1007/s12665-016-6124-1A landslide susceptibility map is an essential tool for land-use spatial planning and management in mountain areas. However, a classification system used for readability determines the final appearance of the map and may therefore influence the decision-making tasks adopted. The present paper addresses the spatial comparison and the accuracy assessment of some well-known classification methods applied to a susceptibility map that was based on a discriminant statistical model in an area in the Eastern Pyrenees. A number of statistical approaches (Spearman’s correlation, kappa index, factorial and cluster analyses and landslide density index) for map comparison were performed to quantify the information provided by the usual image analysis. The results showed the reliability and consistency of the kappa index against Spearman’s correlation as accuracy measures to assess the spatial agreement between maps. Inferential tests between unweighted and linear weighted kappa results showed that all the maps were more reliable in classifying areas of highest susceptibility and less reliable in classifying areas of low to moderate susceptibility. The spatial variability detected and quantified by factorial and cluster analyses showed that the maps classified by quantile and natural break methods were the closest whereas those classified by landslide percentage and equal interval methods displayed the greatest differences. The difference image analysis showed that the five classified maps only matched 9 % of the area. This area corresponded to the steeper slopes and the steeper watershed angle with forestless and sunny slopes at low altitudes. This means that the five maps coincide in identifying and classifying the most dangerous areas. The equal interval map overestimated the susceptibility of the study area, and the landslide percentage map was considered to be a very optimistic model. The spatial pattern of the quantile and natural break maps was very similar, but the latter was more consistent and predicted potential landslides more efficiently and reliably in the study area.Peer ReviewedPreprin

Deep reactive ion etching of auxetic structures: present capabilities and challenges

Auxetic materials (or metamaterials) have negative Poisson ratios (NPR) and display the unexpected properties of lateral expansion when stretched, and equal and opposing densification when compressed. Such auxetic materials are being used more frequently in the development of novel products, especially in the fields of intelligent expandable actuators, shape-morphing structures, and minimally invasive implantable devices. Although several micromanufacturing technologies have already been applied to the development of auxetic materials and devices, additional precision is needed to take full advantage of their special mechanical properties. In this study, we present a very promising approach for the development of auxetic materials and devices based on the use of deep reactive ion etching (DRIE). The process stands out for its precision and its potential applications to mass production. To our knowledge, it represents the first time this technology has been applied to the manufacture of auxetic materials with nanometric details. We take into account the present capabilities and challenges linked to the use of DRIE in the development of auxetic materials and auxetic-based devices

A wearable passive force sensor/active interrogator intended for intra-splint use for the detection and recording of bruxism

A wearable bite force sensing system proto type made up of a passive force sensor and an active interrogator/reader is described. The system is aimed a* bite sensing using a wireless link between the passive sensor to be located in (lie moutb and the external interrogator that can record the evolution of detected force. The interrogator generates a magnetic field that energizes the passive sensor which is also used as the information transmission earlier. The passive farce sensor does not need a battery to operate it because it can extract the energy it needs to operate fmin the carrier field generated by the interrogator. Occlusal force quantification can be used for the detection of bruxing episodes and registration. The small size of the components used (sind) and its further size reduction if they are integrated would allow an implant the size of a tooth

Effect of rockfall fragmentation on exposure and subsequent risk analysis

Rockfalls are frequent natural processes in mountain regions with the potential to produce damage. The quantitative risk analysis (QRA) is an approach increasingly used to assess risk and evaluate the performance of mitigation measures. In case of the fragmentation of the falling rock mass, some of the hypothesis taken in the QRA estimation for rockfalls have to be modified since a single block or rock mass can produce several fragments thus modifying the runout probability, the impact energies and exposure of the elements at risk. In this contribution, we present a procedure to account for the exposure in QRA analysis along linear paths using the fragmental rockfall propagation model RockGIS (Matas et al. 2017). The procedure is applied at the “Monasterio de Piedra”, Spain as part of a QRA.Postprint (published version

Rapid prototyping of multi-scale biomedical microdevices by combining additive manufacturing technologies

The possibility of designing and manufacturing biomedical microdevices with multiple length-scale geometries can help to promote special interactions both with their environment and with surrounding biological systems. These interactions aim to enhance biocompatibility and overall performance by using biomimetic approaches. In this paper, we present a design and manufacturing procedure for obtaining multi-scale biomedical microsystems based on the combination of two additive manufacturing processes: a conventional laser writer to manufacture the overall device structure, and a direct-laser writer based on two-photon polymerization to yield finer details. The process excels for its versatility, accuracy and manufacturing speed and allows for the manufacture of microsystems and implants with overall sizes up to several millimeters and with details down to sub-micrometric structures. As an application example we have focused on manufacturing a biomedical microsystem to analyze the impact of microtextured surfaces on cell motility. This process yielded a relevant increase in precision and manufacturing speed when compared with more conventional rapid prototyping procedures

Ten Years of CDIO Experiences Linked to Toy Design

Toys are deeply rooted to the natural learning process of children, as they investigate for themselves learning cause effect relationships and the relevance of boundary conditions, and to the development of their personality and social skills, as they observe and interact with other children and adults when playing. Learning through play, promoted by pioneers as Montessori, Piaget and Steiner, is among the most powerful teaching-learning strategies and currently forms part of high-quality curricula worldwide, mainly from early childhood to high school. Our experience shows that it can be also successfully applied to higher Education and that living through the complete engineering design process of real toys, following the CDIO scheme, is an excellent strategy for making engineering students face real industrial challenges while they design, dream, play and learn. A decade ago we started to set the foundations towards the European Area of Higher Education, which should promote active learning in contexts more linked to professional practice. To this end, several courses in our Industrial Engineering Degree began to incorporate project-based learning activities, although initially with a more limited scope than that of the integral CDIO approach, as fundamental part of the teaching-learning process. In our course on “Design and manufacturing with polymers” we opted for including capstone collaborative projects linked to designing real plastic products and the related massproduction tools. We decide to propose students to design toys and the related injection molds, which constitute great examples of complex engineering systems, using state-of-theart industrial methodologies and resources. The topic of “toy design” has proven to be motivating for students and teachers and has helped us to re-invent the course in every edition. Our course has served as application example of the benefits of student-centered teaching-learning strategies at ETSII-UPM along the implementation of the “Bologna process”, which has culminated with the beginning of the Master’s Degree in Industrial Engineering, a programme that devotes more than a 20% of activities to project-based learning following the CDIO standards, in which the detailed course continues as part of the Mechanical Engineering major. Here we present a summary of the course evolution during the last decade and analyze its main teaching-learning results. To our knowledge, this “complete toy design experience” constitutes one of the first integral applications of the CDIO methodology to the field of Industrial Engineering in our country and stands out for ten years of continuous improvements. Around 500 students have taken part in these projects from our “Design and manufacturing with polymers” course at ETSII-UPM and more than 200 real toys, together with the related injection molding mass-production tools, have been designed during the last ten years. The most outstanding designs have been manufactured and tested every year for letting students live the whole CDIO cycl

Evaluation of social context integrated into the study of seismic risk for urban areas

Usually the seismic risk evaluation involves only the estimation of the expected physical damage, casualties or economic losses. This article corresponds to a holistic approach for seismic risk assessment which involves the evaluation of the social fragility and the lack of resilience. The complementary evaluation of social context aspects such as the distribution of the population, the absence of economic and social development, deficiencies in institutional management, and lack of capacity for response and recovery; is useful in order to have seismic risk evaluation suitable to support a decision making processes for risk reduction. The proposed methodology allows a standardized assessment of the social fragility and lack of resilience, by means of an aggravating coefficient of which summarizes the characteristics of the social context using fuzzy sets and Analytic Hierarchy Process (AHP). The selection of 20 social indicators is based on the indicators used by urban observatories of United Nations and other social researchers. These indicators are classified according to social item they describe, in six categories. Applying the determination level analysis, thirteen prevailing social indicators are selected. The proposed methodology has been applied in the cities of Merida (Venezuela) and Barcelona (Spain).Peer ReviewedPostprint (published version

Modelling of the mechanical behaviour of the photopolymerization processes of resins intended for additive manufacturing (AMT) using laserstereolithography: The influence on part quality

This study presents a simplified model of the polymerization process of photo-cured epoxy resin, with the aim of finding theoretical values for the mechanical properties of the material in its transition stage from liquid to solid state, approximating these properties to a single figure at the instant of its gelation in the time denominated as tg. By evaluating a phenomenon observed during the fabrication of samples using a stereolithography additive manufacturing printer, it is hoped to fit a model that will replicate the mechanical forces undergone by the manufactured part. The introduction of new hypotheses to simplify the case under study will be tested by simulating these cases using the finite element method, taking the values obtained from previous publications that used experimental and analytical analysis so that the congruence of the results will be constant throughout the model. Finding these theoretical values will help develop future criteria for the feasibility of manufacturing the parts using laser stereolithography and therefore have a direct influence on the quality of the end part

Sostenible - No sostenible

Esta breve contribución, dentro del bloque temático “Iniciativas-motor de cambio”, contiene una idea principal: la insostenibilidad intrínseca del desarrollo humano. Afortunadamente, esta “no-sostenibilidad” es sólo un tema de nomenclatura que se refiere al significado literal del término; no es un problema de fondo que cuestione la necesidad de desarrollar políticas y estrategias orientadas al Desarrollo Humano “Sostenible” (DHS).Peer Reviewe

Micro-vascular shape-memory polymer actuators with complex geometries obtaines by laser stereolithography

In our work we present the complete development process of geometrically complex microvascular shape-memory polymer actuators. The complex geometries and three-dimensional networks are designed by means of computer aided design resources. Manufacture is accomplished, in a single step, by means of laser stereolithography, directly from the computeraided design files with the three dimensional geometries of the different actuators under development. To our knowledge, laser stereolithography is applied here for the first time to the development of shape memory polymer devices with complex geometries and inner microvasculatures for their activation using a thermal fluid. Final testing of the developed actuators helps to validate the approach and to put forward some present challenges