6,641 research outputs found
Alternative method for the metrological characterization of spur gears in the sub-millimeter range using optical equipment
The aim of this work is to develop a software that allows the inspection of spur gear manufactured in the sub-millimeter range. The measurements are made using a digital optical machine and using an analysis proprietary software implemented in Matlab®, which is able to handle images, captured using the digital optical machine. The software allows to evaluate the profile and pitch deviations as establish in the ISO/TR 10064-1:1992 standar
An innovative cooperative model for the Master Degree Project of Architecture. Overcoming the traditional system.
http://dx.doi.org/10.4995/HEAD17.2017.6713Although the Bologna’s process has highlighted the need to develop deep and structural changes in the educational institutions, there is a scarce bibliography on innovation projects in Master Degree Projects, specifically in the field of Architecture. This paper is part of a educational innovative reaserch project that is proposing a cooperative process-and-product model-based for MDP. The model is developed in three stages, from collaborative learning action groups to indivual project. At the end of the process the student has developed three documents: a presentation, a product and a daily-portfolio. Finally, MDP assessment is the sum of three evaluationsUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Optimizing Scan Homogeneity for Building Full-3D Lidars based on Rotating a Multi-Beam Velodyne Rangefinder
Multi-beam lidar (MBL) scanners are compact, light, and accessible 3D sensors with high data rates, but they offer limited vertical resolution and field of view (FOV).
Some recent robotics research has profited from the addition of a degree-of-freedom (DOF) to an MBL to build rotating multi-beam lidars (RMBL) that can achieve high-resolution scans with full spherical FOV. In a previous work, we offered a methodology to analyze the complex 3D scan measurement distributions produced by RMBLs with a rolling DOF and no pitching. In this paper, we investigate the effect of introducing constant pitch angles in the construction of the RMBLs with the purpose of finding a kinematic configuration that optimizes scan homogeneity with a spherical FOV. To this end, we propose a scalar index of 3D sensor homogeneity that is based on the spherical formulation of Ripley's K function. The optimization is performed for the widely used Puck (VLP-16) and HDL-32 sensors by Velodyne.This work was partially funded by the Spanish project {DPI2015-65186-R}. The publication has received support from Universidad de Málaga, Campus de Excelencia Andalucía Tech
La contribución de la mujer en la economÃa rural de Castilla y León
La participación de la mujer en el tejido socioeconómico de las zonas rurales se ha visto frecuentemente infravalorada. Sin embargo, desde hace pocos años existe una clara conciencia por parte de los poderes públicos de que la inclusión de la mujer en las estrategias de dinamización socioeconómica del mundo rural es fundamental para fijar población y generar renta y empleo. El objetivo de este trabajo se centra en determinar la contribución económica de la mujer en el desarrollo del medio rural de la Comunidad Autónoma de Castilla y León. Para ello, se ha analizado la relación existente entre el grado de desarrollo de los municipios rurales y las caracterÃsticas socioeconómicas de las mujeres que los habitan. Para alcanzar tal fin, se han empleado tres tipos de técnicas multivariantes: el análisis de componentes principales, la regresión múltiple y el análisis de conglomerados. Los resultados alcanzados permiten afirmar que la participación económica y social de la mujer en el medio rural de Castilla y León se configura como una condición indispensable para alcanzar un mayor bienestar y nivel de desarrollo en esas zonas.Género, desarrollo rural, métodos cuantitativos, Castilla y León (España)., Agricultural and Food Policy, J16, O18, R23,
Clinkering and hydration study of non-active and active Belite-Alite-Ye'elimite (BAY) cements
The aim of AIM is to promote industry-driven, interdisciplinary research in material science and engineering in order to provide leading-edge, sustainable solutions to the challenges facing engineers in today’s changing society and environment. http://www.ucl.ac.uk/aim/conference-info/37ccsThe manufacturing process of ye'elimite rich cements emit about 15-37% less CO2 to the atmosphere than OPC. Cements that contain belite, ye’elimite and ferrite, known as BYF cements, are promising eco-friendly binders. However, belite, their main phase, shows a slow hydrating behaviour; therefore the corresponding mortars present lower mechanical strengths than OPC at early ages. To solve this problem, BYF clinkers can be activated by: i) forming alite jointly with belite and ye’elimite during clinkering, known as BAY clinkers. The alite and ye’elimite reaction with water should develop high mechanical strengths at early ages, besides, belite contributes to later curing times. ii) A second activation is based on the stabilisation of alpha forms of belite by dopants. The objective of this work is to obtain two types of BAY clinkers (standard and active BAY) using CaF2 as mineraliser and borax as dopant agent to stabilize alpha forms of belite phase. After that, anhydrite was added as sulphate source to obtain the corresponding cements. The hydration behaviour of these cements has been studied through rheological and x-ray diffraction measurements, the latter combined with Rietveld quantitative phase analysis. In addition, mechanical and dimensional properties of BAY mortars are also presented and discussed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
A near zero consumption building as an urban acupuncture for a vertical slum. A case study in the city of Malaga, Spain
Vertical slum is defined as a particularly vulnerable height building, with serious problems of functionality, safety and habitability. Venezuela’s Tower of David is a famous example. Vertical slums are associated with an important level of physical degradation, coupled with a precarious socioeconomic situation of its occupants. Their inability to create a community for proper and mandatory maintenance increases their physical deterioration. The abandonment of the original owners is replaced by a system of occupation and illegal activities. In many cases, with an interest in maintaining the building in a state of precariousness, which annuls any attempt to rehabilitate it
Facing this situation, the intervention is proposed through an urban acupuncture project, understood as a project of expropriation and physical rehabilitation of the building, associated to a project of social rehabilitation in a disadvantaged environment. It is about creating a hybrid building associated with four objectives
1- Create a hybrid building with a mixed offer of social and housing services: sheltered housing for seniors, residence and accommodation for young entrepreneurs. The idea of a social condenser is related to studies of the hybrid building such as the Downtown Athletic Club in New York, or the Rokade Tower and Maartenshof residence (Groningen, The Netherlands).
2- Incorporate the sustainability parameters directed to a building almost zero.
3- Incorporate a model of provision of housing services, managed by the municipality, but with the possibility of incorporating NGOs
4- Design a social rehabilitation project that facilitates the creation of a web of social-based companies or cooperatives that fosters entrepreneurship, and that can actively participate in the rehabilitation and maintenance of the neighborhood itself.
This paper applies these principles to a building in Malaga as a case study and 10 strategies are developed and analysed in regards to its physical, social and sustainable transformation.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Validación con datos in-situ de alturas de ola obtenidas mediante radar altimétrico
Los rádares altimétricos a bordo de satélites artificiales, han sido diseñados para dar información precisa de la altura del nivel del mar, la altura de ola significante y la velocidad del viento sobre la superficie del mar. En los estudios, tanto anteriores como actuales, se observan problemas en las regiones costeras, donde las medidas del altímetro tienen menor precisión y una mayor dificultad a la hora de interpretar estos datos. Estos inconvenientes son debidos a dos factores principales. En primer lugar, la contaminación de la señal radar debido a la cercanía de la costa. En segundo lugar, inexactitudes en las correcciones de marea y troposférica húmeda. A estos problemas se añade la complejidad de la zona de estudio, al ser una región con una amplia gama de procesos hidrodinámicos con diversas escalas espacio-temporales. Tener acceso a información exacta en la costa, con las condiciones que conlleva, tiene una gran importancia debido al enorme interés económico-estratégico de la zona litoral. Este interés hace que surjan nuevas estrategias para generar productos altimétricos optimizados para tales condiciones.
Las medidas de la altura de ola significante y su variabilidad en las áreas costeras son usadas para muchos propósitos (por ejemplo, análisis del transporte de sedimento, setup de la ola y tormentas de marea), y para la validación/calibración de modelos (pronóstico de oleaje, circulación oceánica). Estas aplicaciones sirven para un amplio rango de propósitos sociales relevantes, tales como el diseño de estructuras de ingeniería en alta mar, la protección de las zonas costeras, rutas para los buques y la planificación de las operaciones en el océano. Muchos estudios se han dedicado a la validación de los datos de la altura de ola significante dados por el radar altimétrico a bordo de satélites artificiales, utilizando observaciones in-situ.
El objetivo de esta ponencia es exponer una metodología para validar los datos de altura de oleaje proporcionados por el radar altimétrico RA-2 a bordo del satélite ENVISAT, a partir de datos in-situ medidos por una boya, y su aplicación a un caso particular
A proposal for the metrological characterization of circular features with digital optical machines
This paper aims to analyze the different adjustment methods commonly used to characterize indirect metrology circular features: least square circle, minimum zone circle, maximum inscribed circle and minimum circumscribed circle. The analysis was performed from images obtained by digital optical machines. The calculation algorithms, self-developed, have been implemented in Matlab® and take into consideration as study variables: the amplitude of angular sector of the circular feature, its nominal radio and the magnification used by the optical machine. Under different conditions, it was determined the radius and circularity error of different circular standards. The comparison of the results, obtained by the different methods of adjustments used, with certified values for the standards, has allowed us to determine the accuracy of each method and its scope
Rietveld Quantitative Phase Analysis of Oil Well Cement: in Situ Hydration Study at 150 Bars and 150 °C
Oil and gas well cements are multimineral materials that hydrate under high pressure
and temperature. Their overall reactivity at early ages is studied by a number of techniques
including through the use of the consistometer. However, for a proper understanding of the
performance of these cements in the field, the reactivity of every component, in real‐world
conditions, must be analysed. To date, in situ high energy synchrotron powder diffraction studies
of hydrating oil well cement pastes have been carried out, but the quality of the data was not
appropriated for Rietveld quantitative phase analyses. Therefore, the phase reactivities were
followed by the inspection of the evolution of non‐overlapped diffraction peaks. Very recently, we
have developed a new cell specially designed to rotate under high pressure and temperature. Here,
this spinning capillary cell is used for in situ studies of the hydration of a commercial oil well
cement paste at 150 bars and 150 °C. The powder diffraction data were analysed by the Rietveld
method to quantitatively determine the reactivities of each component phase. The reaction degree
of alite was 90% after 7 hours, and that of belite was 42% at 14 hours. These analyses are accurate,
as the in situ measured crystalline portlandite content at the end of the experiment, 12.9 wt%,
compares relatively well with the value determined ex situ by thermal analysis, i.e., 14.0 wt%. The
crystalline calcium silicates forming at 150 bars and 150 °C are also discussed.This research was funded by Spanish MINECO, grant number BIA2017‐82391‐R which is co‐funded
by FEDER.
We thank Marc Malfois for his help during the experiment performed at NCD‐SWEET
beamline at ALBA synchrotron. We also thank Marcus Paul (Dyckerhoff GmbH) for providing the OWC
sample with its characterization and helpful discussions
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