940 resultados para Research Subject Categories::TECHNOLOGY::Other technology::Environmental engineering


Relevância:

100.00% 100.00%

Publicador:

Resumo:

The episodic occurrence of debris flow events in response to stochastic precipitation and wildfire events makes hazard prediction challenging. Previous work has shown that frequency-magnitude distributions of non-fire-related debris flows follow a power law, but less is known about the distribution of post-fire debris flows. As a first step in parameterizing hazard models, we use frequency-magnitude distributions and cumulative distribution functions to compare volumes of post-fire debris flows to non-fire-related debris flows. Due to the large number of events required to parameterize frequency-magnitude distributions, and the relatively small number of post-fire event magnitudes recorded in the literature, we collected data on 73 recent post-fire events in the field. The resulting catalog of 988 debris flow events is presented as an appendix to this article. We found that the empirical cumulative distribution function of post-fire debris flow volumes is composed of smaller events than that of non-fire-related debris flows. In addition, the slope of the frequency-magnitude distribution of post-fire debris flows is steeper than that of non-fire-related debris flows, evidence that differences in the post-fire environment tend to produce a higher proportion of small events. We propose two possible explanations: 1) post-fire events occur on shorter return intervals than debris flows in similar basins that do not experience fire, causing their distribution to shift toward smaller events due to limitations in sediment supply, or 2) fire causes changes in resisting and driving forces on a package of sediment, such that a smaller perturbation of the system is required in order for a debris flow to occur, resulting in smaller event volumes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this paper, the results of six years of research in engineering education, in the application of the European Higher Education Area (EHEA) to improve the performance of the students in the subject Analysis of Circuits of Telecommunication Engineering, are analysed taking into consideration the fact that there would be hidden variables that both separate students into subgroups and show the connection among several basic subjects such as Analysis of Circuits (AC) and Mathematics (Math). The discovery of these variables would help us to explain the characteristics of the students through the teaching and learning methodology, and would show that there are some characteristics that instructors do not take into account but that are of paramount importance

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The core concepts, or threads, of Biosystems Engineering (BSEN) are variously understood by those within the discipline, but have never been unequivocally defined due to its early stage of development. This makes communication and teaching difficult compared to other well established engineering subjects. Biosystems Engineering is a field of Engineering which int egrates engineering science and design with applied biological, environmental and agricultural sciences. It represents an evolution of the Agricultural Engineering discipline applied to all living organisms not including biomedical applications. The basic key element for the emerging EU Biosystems Engineering program of studies is to ensure that it offers essential minimum fundamental engine ering knowledge and competences . A core curriculum developed by Erasmus Thematic Networks is used as benchmark for Agr icultural and Biosystems Engineering studies in Europe. The common basis of the core curriculum for the discipline across the Atlantic , including a minimum of competences comprising the Biosystems Engineering core competencies, has been defined by an Atlan tis project , but this needs to be taken further by defining the threads linking courses together. This paper presents a structured approach to define the Threads of BSEN . The definition of the mid-level competences and the associated learning outcomes has been one of the objectives of the Atlantis programme TABE.NET. The mid-level competences and learning outcomes for each of six specializations of BSEN are defined while the domain-specific knowledge to be acquired for each outcome is proposed. Once the proposed definitions are adopted, these threads will be available for global development of the BSEN.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The boundary element method (BEM) has been applied successfully to many engineering problems during the last decades. Compared with domain type methods like the finite element method (FEM) or the finite difference method (FDM) the BEM can handle problems where the medium extends to infinity much easier than domain type methods as there is no need to develop special boundary conditions (quiet or absorbing boundaries) or infinite elements at the boundaries introduced to limit the domain studied. The determination of the dynamic stiffness of arbitrarily shaped footings is just one of these fields where the BEM has been the method of choice, especially in the 1980s. With the continuous development of computer technology and the available hardware equipment the size of the problems under study grew and, as the flop count for solving the resulting linear system of equations grows with the third power of the number of equations, there was a need for the development of iterative methods with better performance. In [1] the GMRES algorithm was presented which is now widely used for implementations of the collocation BEM. While the FEM results in sparsely populated coefficient matrices, the BEM leads, in general, to fully or densely populated ones, depending on the number of subregions, posing a serious memory problem even for todays computers. If the geometry of the problem permits the surface of the domain to be meshed with equally shaped elements a lot of the resulting coefficients will be calculated and stored repeatedly. The present paper shows how these unnecessary operations can be avoided reducing the calculation time as well as the storage requirement. To this end a similar coefficient identification algorithm (SCIA), has been developed and implemented in a program written in Fortran 90. The vertical dynamic stiffness of a single pile in layered soil has been chosen to test the performance of the implementation. The results obtained with the 3-d model may be compared with those obtained with an axisymmetric formulation which are considered to be the reference values as the mesh quality is much better. The entire 3D model comprises more than 35000 dofs being a soil region with 21168 dofs the biggest single region. Note that the memory necessary to store all coefficients of this single region is about 6.8 GB, an amount which is usually not available with personal computers. In the problem under study the interface zone between the two adjacent soil regions as well as the surface of the top layer may be meshed with equally sized elements. In this case the application of the SCIA leads to an important reduction in memory requirements. The maximum memory used during the calculation has been reduced to 1.2 GB. The application of the SCIA thus permits problems to be solved on personal computers which otherwise would require much more powerful hardware.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Análisis de precisión en modelos digitales de elevación globales. ABSTRACT: Terrain-Based Analysis results in derived products from an input DEM and these products are needed to perform various analyses. To efficiently use these products in decision-making, their accuracies must be estimated systematically. This paper proposes a procedure to assess the accuracy of these derived products, by calculating the accuracy of the slope dataset and its significance, taking as an input the accuracy of the DEM. Based on the output of previously published research on modeling the relative accuracy of a DEM, specifically ASTER and SRTM DEMs with Lebanon coverage as the area of study, analysis have showed that ASTER has a low significance in the majority of the area where only 2% of the modeled terrain has 50% or more significance. On the other hand, SRTM showed a better significance, where 37% of the modeled terrain has 50% or more significance. Statistical analysis deduced that the accuracy of the slope dataset, calculated on a cell-by-cell basis, is highly correlated to the accuracy of the input DEM. However, this correlation becomes lower between the slope accuracy and the slope significance, whereas it becomes much higher between the modeled slope and the slope significance.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The Spanish NGO "Alianza por la Solidaridad" has installed improved cookstoves in 3000 households during 2012 and 2013 to improve energy efficiency reducing fuelwood consumption and to improve indoor air quality. The type of cookstoves were Noflaye Jeeg and Noflaye Jaboot and were installed in the Cassamance Natural Subregion covering part of Senegal, The Gambia and Guinea-Bissau. The Technical University of Madrid (UPM) has conducted a field study on a sample of these households to assess the effect of improved cookstoves on kitchen air quality. Measurements of carbon monoxide (CO) and fine particle matter (PM2.5) were taken for 24-hr period before and after the installation of improved cookstoves. The 24-hr mean CO concentrations were lower than the World Health Organization (WHO) guidelines for Guinea-Bissau but higher for Senegal and Gambia, even after the installation of improved cookstoves. As for PM2.5 concentrations, 24-hr mean were always higher than these guidelines. However, improved cookstoves produced significant reductions on 24-hr mean CO and PM2.5 concentrations in Senegal and for mean and maximum PM2.5 concentration on Gambia. Although this variability needs to be explained by further research to determine which other factors could affect indoor air pollution, the study provided a better understanding of the problem and envisaged alternatives to be implemented in future phases of the NGO project.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Este documento presenta el diseño de un proyecto para la asignatura de tecnología de tercero de educación secundaria obligatoria en un instituto de enseñanza bilingüe. Se perfilan una serie de tareas cíclicas que permitirán desarrollar a los alumnos una mayor comprensión sobre el uso de la energía y la importancia del medio ambiente a través de la lengua inglesa. Este ciclo de actividades organizadas en cuatro sesiones se fundamenta en la metodología del Aprendizaje Integrado de Contenidos y Lengua Extranjera, AICLE. A través de esta se persigue el doble objetivo del aprendizaje de la lengua a la par que el del contenido. Para ello, las estrategias que se proponen se centran en el alumno y se apoyan en el trabajo colaborativo, la interacción entre iguales y las metodologías activas y participativas en las que son los propios estudiantes los que diseñan los contenidos y los adaptan a su estilo de aprendizaje. Aunque sin resultados concluyentes, el trabajo supone una aportación más a las propuestas de actividades cooperativas que centran el aprendizaje en las aulas AICLE. This project presents the design of a teaching sequence for the subject of technology in the third grade in a bilingual high school. A task cycle is created with the double objective of providing students with a deeper understanding about the use of energy and the importance of the environment through the English language. The series of activities were organized in four sessions, attending to Content and Language Integrated Learning (CLIL) methodology. Throughout this double focussed objective of learning the language and the subject matter content at the same time, the strategies proposed are focused on the student and support collaborative work, peer interaction and active participatory methodologies, focussed in the students who are the real designers of the content materials based on their own learning style. Although no conclusive results are presented, this work aims to be a contribution to other cooperative task proposals as one of the main basis of CLIL methodology.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Desde hace más de una década se vienen realizando en España enormes esfuerzos por implantar programas bilingües español-inglés en los centros educativos y es, por tanto, de gran interés conocer qué efectos ha tenido y está teniendo actualmente la implantación de dichos programas en los alumnos. Son, así pues, objetivos de este trabajo: identificar los efectos de la educación bilingüe en España, establecer propuestas de mejora frente a los problemas o insuficiencias detectadas y, por último, ofrecer una serie de propuestas relativas a la elaboración de materiales didácticos dentro del enfoque metodológico de Aprendizaje Integrado de Contenidos y Lenguas Extranjeras (AICLE). Se presentan también un banco de recursos didácticos de apoyo a uno de los bloques en los que se organiza la asignatura de Tecnología de la Enseñanza Secundaria Obligatoria, los resultados esperados del proyecto, una propuesta de valoración de la puesta en práctica del mismo y, como conclusión, se valoran positivamente este tipo de recursos y se propone la conveniencia de desarrollar nuevos recursos didácticos que aborden otras temáticas dentro de la Tecnología. ABSTRACT From the mid-nineties onwards great efforts have been made in Spain in order to implement bilingual education programs into primary and secondary schools. Therefore, this work’s main objectives are to identify the effects of bilingual education in Spain and to make proposals for the improvement or elimination of the identified problems and weaknesses and for creating Content and Language Integrated Learning- specific learning materials. The work also includes a teacher resource bank to support one of the blocks in which the subject of Technology in Secondary Education is organized, the expected results, an assessment plan to measure the project’s success and, as a conclusion, it is highlighted the need for creating new materials that address other thematic areas within the subject of Tecnology.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

El trabajo desarrollado pretende dar a conocer cuales son las necesidades especificas de alumnos con trastorno del espectro autista (TEA).Se enmarca en los estudios que afrontan la temática de la Atención a Diversidad y la inclusión de los alumnos con TEA en centros ordinarios educativos. Se pretende desarrollar recursos metodológicos para ofrecer una respuesta adaptativa ante el reto de afrontar las competencias clave a través de la nueva asignatura de “Tecnología, programación y robótica”; Para ello se analizan las características de cuatro estudiantes con TEA escolarizados en secundaria del centro concertado Colegio Lourdes (FUHEM) de la comunidad de Madrid y se ofrecen respuestas diferentes en función de ellas, apoyándonos en sus fortalezas para vencer sus dificultades, con el objetivo de alcanzar las mismas competencias claveque el resto de compañeros, como marca la Ley Orgánica de Mejora de la Calidad de la Educación, LOMCE, que entra en vigor en este nivel en el curso 2015-2016. ABSTRACT The developed work seeks to highlight what are the specific needs of students with autism spectrum (ASDs).The part of the studies faced the issue of Attention to diversity and the inclusion of students with ASD in mainstream schools educational disorder. It aims to develop methodological resources to offer an adaptive response to the challenge of addressing key skills through the new subject of "Technology, Programming and Robotics"; To do the characteristics of four students with ASD are discussed in secondary school concerted Lourdes (FUHEM) of the Madrid and different responses depending on them are offered, building on their strengths to overcome their difficulties, in order to achieve the same core competencies of other colleagues as brand organic law of Quality Improvement of Education, LOMCE, which takes effect in the 2015-2016 year.