935 resultados para Technical specifications
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The apparition of new mobile phones operating systems often leads to a flood of mobile applications rushing into the market without taking into account needs of the most vulnerable users groups: the people with disabilities. The need of accessible applications for mobile is very important especially when it comes to access basic mobile functions such as making calls through a contact manager. This paper presents the technical validation process and results of an Accessible Contact Manager for mobile phones as a part of the evaluation of accessible applications for mobile phones for people with disabilities.
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The results obtained after incorporating the competence “creativity” to the subject Technical Drawing of the first course of the Degree in Forestry, Technical University of Madrid, are presented in this study.At first, learning activities which could serve two functions at the same time -developing students’ creativity and developing other specific competences of the subject- were considered. Besides, changes in the assessment procedure were made and a method which analyzes two aspects of the assessment of the competence creativity was established. On the one hand, the products are evaluated by analyzing the outcomes obtained by students in the essays suggested and by establishing a parameter to assess the creativity expressed in those essays. On the other, an assessment of the student is directly carried out through a psychometric test which has been previously chosen by the team.Moreover, these results can be applied to similar or could be of general application
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The heterogeneous incoming heat flux in solar parabolic trough absorber tubes generates huge temperature difference in each pipe section. Helical internal fins can reduce this effect, homogenising the temperature profile and reducing thermal stress with the drawback of increasing pressure drop. Another effect is the decreasing of the outer surface temperature and thermal losses, improving the thermal efficiency of the collector. The application of internal finned tubes for the design of parabolic trough collectors is analysed with computational fluid dynamics tools. Our numerical approach has been qualified with the computational estimation of reported experimental data regarding phenomena involved in finned tube applications and solar irradiation of parabolic trough collector. The application of finned tubes to the design of parabolic trough collectors must take into account issues as the pressure losses, thermal losses and thermo-mechanical stress, and thermal fatigue. Our analysis shows an improvement potential in parabolic trough solar plants efficiency by the application of internal finned tubes.
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The competence evaluation promoted by the European High Education Area entails a very important methodological change that requires guiding support to help teachers carry out this new and complex task. In this regard, the Technical University of Madrid (UPM, by its Spanish acronym) has financed a series of coordinated projects with a two-fold objective: a) To develop a model for teaching and evaluating core competences that is useful and easily applicable to its different degrees, and b) to provide support to teachers by creating an area within the Website for Educational Innovation where they can search for information on the model corresponding to each core competence approved by UPM. Information available on each competence includes its definition, the formulation of indicators providing evidence on the level of acquisition, the recommended teaching and evaluation methodology, examples of evaluation rules for the different levels of competence acquisition, and descriptions of best practices. These best practices correspond to pilot tests applied to several of the academic subjects conducted at UPM in order to validate the model. This work describes the general procedure that was used and presents the model developed specifically for the problem-solving competence. Some of the pilot experiences are also summarised and their results analysed
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The use of ion microbeams as probes for computedtomography has proven to be a powerful tool for the three-dimensional characterization of specimens a few tens of micrometers in size. Compared to other types of probes, the main advantage is that quantitative information about mass density and composition can be obtained directly, using specific reconstruction codes. At the Centre d’Etudes Nucléaires de Bordeaux Gradignan (CENBG), this technique was initially developed for applications in cellular biology. However, the observation of the cell ultrastructure requires a sub-micron resolution. The construction of the nanobeamline at the Applications Interdisciplinaires des Faisceaux d’Ions en Region Aquitaine (AIFIRA) irradiation facility has opened new perspectives for such applications. The implementation of computedtomography on the nanobeamline of CENBG has required a careful design of the analysis chamber, especially microscopes for precise sample visualization, and detectors for scanning transmission ion microscopy (STIM) and for particle induced X-ray emission (PIXE). The sample can be precisely positioned in the three directions X, Y, Z and a stepper motor coupled to a goniometer ensures the rotational motion. First images of 3D tomography were obtained on a reference sample containing microspheres of certified diameter, showing the good stability of the beam and the sample stage, and the precision of the motion.
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Inverter features are reviewed from a PV systems perspective, with a view to contributing to possible codes, procurement specifications and testing procedures, in order to assure the technical quality of these systems. A laboratory testing campaign has been carried out on a representative set of sixteen currently available inverters and a set of the most common AC appliances. The results of the tests are discussed with the aim of divulging the particular features of operating AC appliances in PV systems and the provisions to be taken into account in PV system design. The development of testing procedures has followed the motto ?keep it as simple as possible?, in order to make their application easier in conventional laboratories in developing countries.
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The technique of Abstract Interpretation [11] has allowed the development of sophisticated program analyses which are provably correct and practical. The semantic approximations produced by such analyses have been traditionally applied to optimization during program compilation. However, recently, novel and promising applications of semantic approximations have been proposed in the more general context of program validation and debugging [3,9,7].
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Esta Tesis Doctoral se encuadra en el ámbito de la medida de emisiones contaminantes y de consumo de combustible en motores de combustión interna alternativos cuando se utilizan como plantas de potencia para propulsión de vehículos ligeros de carretera, y más concretamente en las medidas dinámicas con el vehículo circulando en tráfico real. En este ámbito, el objetivo principal de la Tesis es estudiar los problemas asociados a la medición en tiempo real con equipos embarcados de variables medioambientales, energéticas y de actividad, de vehículos ligeros propulsados por motores térmicos en tráfico real. Y como consecuencia, desarrollar un equipo y una metodología apropiada para este objetivo, con el fin de realizar consiguientemente un estudio sobre los diferentes factores que influyen sobre las emisiones y el consumo de combustible de vehículos turismo en tráfico real. La Tesis se comienza realizando un estudio prospectivo sobre los trabajos de otros autores relativos al desarrollo de equipos portátiles de medida de emisiones (Portable Emission Measurement Systems – PEMS), problemas asociados a la medición dinámica de emisiones y estudios de aplicación en tráfico real utilizando este tipo de equipos. Como resultado de este estudio se plantea la necesidad de disponer de un equipo específicamente diseñado para ser embarcado en un vehículo que sea capaz de medir en tiempo real las concentraciones de emisiones y el caudal de gases de escape, al mismo tiempo que se registran variables del motor, del vehículo y del entorno como son la pendiente y los datos meteorológicos. De esta forma se establecen las especificaciones y condiciones de diseño del equipo PEMS. Aunque al inicio de esta Tesis ya existían en el mercado algunos sistemas portátiles de medida de emisiones (PEMS: Portable Emissions Measurement Systems), en esta Tesis se investiga, diseña y construye un nuevo sistema propio, denominado MIVECO – PEMS. Se exponen, discuten y justifican todas las soluciones técnicas incorporadas en el sistema que incluyen los subsistema de análisis de gases, subsistemas de toma de muestra incluyendo caudalímetro de gases de escape, el subsistema de medida de variables del entorno y actividad del vehículo y el conjunto de sistemas auxiliares. El diseño final responde a las hipótesis y necesidades planteadas y se valida en uso real, en banco de rodillos y en comparación con otro equipos de medida de emisiones estacionarios y portátiles. En esta Tesis se presenta también toda la investigación que ha conducido a establecer la metodología de tratamiento de las señales registradas en tiempo real que incluye la sincronización, cálculos y propagación de errores. La metodología de selección y caracterización de los recorridos y circuitos y de las pautas de conducción, preparación del vehículo y calibración de los equipos forma también parte del legado de esta Tesis. Para demostrar la capacidad de medida del equipo y el tipo de resultados que pueden obtenerse y que son útiles para la comunidad científica, y las autoridades medioambientales en la parte final de esta Tesis se plantean y se presentan los resultados de varios estudios de variables endógenas y exógenas que afectan a las emisiones instantáneas y a los factores de emisión y consumo (g/km) como: el estilo de conducción, la infraestructura vial, el nivel de congestión del tráfico, tráfico urbano o extraurbano, el contenido de biocarburante, tipo de motor (diesel y encendido provocado), etc. Las principales conclusiones de esta Tesis son que es posible medir emisiones másicas y consumo de motores de vehículos en uso real y que los resultados permiten establecer políticas de reducción de impacto medio ambiental y de eficiencia energética, pero, se deben establecer unas metodologías precisas y se debe tener mucho cuidado en todo el proceso de calibración, medida y postratamientos de los datos. Abstract This doctoral thesis is in the field of emissions and fuel consumption measurement of reciprocating internal combustion engines when are used as power-trains for light-duty road vehicles, and especially in the real-time dynamic measurements procedures when the vehicle is being driven in real traffic. In this context, the main objective of this thesis is to study the problems associated with on-board real-time measuring systems of environmental, energy and activity variables of light vehicles powered by internal combustion engines in real traffic, and as a result, to develop an instrument and an appropriate methodology for this purpose, and consequently to make a study of the different factors which influence the emissions and the fuel consumption of passenger cars in real traffic. The thesis begins developing a prospective study on other authors’ works about development of Portable Emission Measurement Systems (PEMS), problems associated with dynamic emission measurements and application studies on actual traffic using PEMS. As a result of this study, it was shown that a measuring system specifically designed for being on-board on a vehicle, which can measure in real time emission concentrations and exhaust flow, and at the same time to record motor vehicle and environment variables as the slope and atmospheric data, is needed; and the specifications and design parameters of the equipment are proposed. Although at the beginning of this research work there were already on the market some PEMS, in this Thesis a new system is researched, designed and built, called MIVECO – PEMS, in order to meet such measurements needs. Following that, there are presented, discussed and justify all technical solutions incorporated in the system, including the gas analysis subsystem, sampling and exhaust gas flowmeter subsystem, the subsystem for measurement of environment variables and of the vehicle activity and the set of auxiliary subsystems. The final design meets the needs and hypotheses proposed, and is validated in real-life use and chassis dynamometer testing and is also compared with other stationary and on-board systems. This thesis also presents all the research that has led to the methodology of processing the set of signals recorded in real time including signal timing, calculations and error propagation. The methodology to select and characterize of the routes and circuits, the driving patterns, and the vehicle preparation and calibration of the instruments and sensors are part of the legacy of this thesis. To demonstrate the measurement capabilities of the system and the type of results that can be obtained and that are useful for the scientific community and the environmental authorities, at the end of this Thesis is presented the results of several studies of endogenous and exogenous variables that affect the instantaneous and averaged emissions and consumption factors (g/km), as: driving style, road infrastructure, the level of traffic congestion, urban and extra-urban traffic, biofuels content, type of engine (diesel or spark ignition) etc. The main conclusions of this thesis are that it is possible to measure mass emissions and consumption of vehicle engines in actual use and that the results allow us to establish policies to reduce environmental impact and improve energy efficiency, but, to establish precise methodologies and to be very careful in the entire process of calibration, measurement and data post-treatment is necessary.
Resumo:
We discuss a framework for the application of abstract interpretation as an aid during program development, rather than in the more traditional application of program optimization. Program validation and detection of errors is first performed statically by comparing (partial) specifications written in terms of assertions against information obtained from (global) static analysis of the program. The results of this process are expressed in the user assertion language. Assertions (or parts of assertions) which cannot be checked statically are translated into run-time tests. The framework allows the use of assertions to be optional. It also allows using very general properties in assertions, beyond the predefined set understandable by the static analyzer and including properties defined by user programs. We also report briefly on an implementation of the framework. The resulting tool generates and checks assertions for Prolog, CLP(R), and CHIP/CLP(fd) programs, and integrates compile-time and run-time checking in a uniform way. The tool allows using properties such as types, modes, non-failure, determinacy, and computational cost, and can treat modules separately, performing incremental analysis.
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El Colegio de Nuestra Señora de la Antigua de Monforte de Lemos (1593-1619) constituye el principal ejemplo del clasicismo herreriano de Galicia. Esta tesis analiza los aspectos técnicos de la construcción de sus bóvedas de cantería, en el marco disciplinar de la Historia de la Construcción. El Colegio contiene varios tipos de bóvedas entre las que destacan su cúpula trasdosada y su escalera monumental. Además, se conservan los documentos notariales históricos que describen las obras y una de las monteas más importantes de Galicia. Las bóvedas han sufrido movimientos y algunas presentan importantes deformaciones, que han suscitado preocupación sobre su estabilidad. El estudio se organiza en tres epígrafes: geometría, construcción y mecánica, tres aspectos estrechamente interrelacionados en este tipo de estructuras. La parte de estudio geométrico parte de un levantamiento en el que se emplea una estación total sin reflectante, una técnica que permite una medición muy precisa de la forma real de las bóvedas. Como complemento se ha recurrido a técnicas de escáner fotográfico. Con los datos de las mediciones se han elaborado los dibujos de las bóvedas, y analizado sus medidas e irregularidades. Se ha incluido un análisis metrológico por métodos inductivos, que ha puesto de manifiesto la unidad utilizada en la construcción. El estudio se completa con la recopilación de las reglas de dimensionamiento que figuran en los tratados, que se comparan con las dimensiones de las bóvedas analizadas. En el estudio constructivo se registran los despieces y la configuración constructiva y se contrastan, por un lado, con las soluciones que aparecen en los principales tratados de los siglos XVI, XVII y XVIII, y por otro, con las descripciones que se encuentran en los documentos históricos del Colegio. Se ha prestado especial atención al estudio de estos documentos, que han permitido conocer algunos aspectos originales del proceso de construcción de estas bóvedas. En una de las paredes del claustro se ha identificado una montea inédita cuyo levantamiento y análisis se incorpora en esta parte. En el estudio mecánico se analiza la estabilidad dentro del marco teórico del Moderno Análisis Límite de Estructuras de Fábricas. La comprensión del comportamiento estructural, unida a la precisión de los levantamientos, ha permitido explicar los movimientos de las fábricas e inferir la geometría original de algunas de las bóvedas, no siempre evidente en los casos de fuertes deformaciones. Los estudios realizados hasta ahora en bóvedas de los siglos XVI y XVII permiten vislumbrar un panorama de soluciones constructivas más rico que el que recogen los tratados históricos. Las nuevas técnicas de medición sin contacto abren nuevas posibilidades para analizar estas estructuras. Los casos estudiados todavía son escasos y se necesita un conjunto más amplio para poder realizar un análisis general. Esta tesis aporta el estudio de uno de esos casos con el fin de contribuir al mejor conocimiento de la construcción en España en los siglos XVI y XVII. ABSTRACT The Colegio de Nuestra Señora de la Antigua (1593-1619), in Monforte de Lemos, Spain, is the best example in Galicia of the classicism influenced by the Monastery of El Escorial and his architect, Juan de Herrera. This thesis analyzes the technical aspects of the construction of its masonry vaults within the discipline of Construction History. The Colegio exhibits various types of vaults, among which the extradosed ashlar dome and the grand staircase are particularly worth mentioning. In addition, the legal documents containing thorough specifications of the work, as well as one of the construction drawings at actual size —one of the best examples in Galicia—, have both been preserved to this date. Some of the vaults have undergone important deformations that have raised concerns about their stability. The study is organized in three sections: geometry, construction, and mechanics, the three clearly interrelated in this type of structures. The geometrical study starts out with a metric survey using a reflectorless total station, a technique that allows a very precise measurement of the actual shape of the vault. This technique was complemented with the use of a photo-based 3D scanner. The resulting measurements were used to draw the vaults, and analyze their dimensions and irregularities. An inductive metrological analysis, which was able to reveal the exact metric unit utilized during the construction, is included in this section. The section is completed with the gathering of the dimensional rules appearing in the various historical treatises, which are compared with the dimensions of the actual vaults. The construction study deals with the quartering of the structure, whose results are compared, on the one hand, with the approaches appearing in the main treatises of the 16th- 18th centuries, and on the other, with the descriptions in the historical documents of the Colegio itself. Special attention has been paid to the study of these documents, which have revealed some original aspects in the construction process of the vaults. In one of the cloister’s walls, a hitherto unheard-of construction drawing at actual size was found. Its survey and analysis is included in this section. The mechanical study analyzes the Colegio's vaults stability within the theoretical frame of the Modern Limit Analysis of Masonry Structures. The interpretation of the structural behavior, coupled with the precision of the surveys, has allowed a deep understanding of the masonry’s movements and the original geometry of some of the vaults —not always evident in the case of strong deformations— has been inferred. The studies dealing with XVI and XVII century vaults conducted up to this date show a landscape of constructive solutions far richer than the one suggested in the historical treatises. The new contactless measuring techniques offer exciting possibilities for the analysis of these structures. The cases studied are still few and more would be needed before a general analysis can be attempted. This thesis constitutes one such additional case and its goal is to improve our understanding of Spanish construction in the 16th-17th centuries.
Resumo:
We present a framework for the application of abstract interpretation as an aid during program development, rather than in the more traditional application of program optimization. Program validation and detection of errors is first performed statically by comparing (partial) specifications written in terms of assertions against information obtained from static analysis of the program. The results of this process are expressed in the user assertion language. Assertions (or parts of assertions) which cannot be verified statically are translated into run-time tests. The framework allows the use of assertions to be optional. It also allows using very general properties in assertions, beyond the predefined set understandable by the static analyzer and including properties defined by means of user programs. We also report briefly on an implementation of the framework. The resulting tool generates and checks assertions for Prolog, CLP(R), and CHIP/CLP(fd) programs, and integrates compile-time and run-time checking in a uniform way. The tool allows using properties such as types, modes, non-failure, determinacy, and computational cost, and can treat modules separately, performing incremental analysis. In practice, this modularity allows detecting statically bugs in user programs even if they do not contain any assertions.
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Abstract is not available.
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A Kuhnian approach to research assessment requires us to consider that the important scientific breakthroughs that drive scientific progress are infrequent and that the progress of science does not depend on normal research. Consequently, indicators of research performance based on the total number of papers do not accurately measure scientific progress. Similarly, those universities with the best reputations in terms of scientific progress differ widely from other universities in terms of the scale of investments made in research and in the higher concentrations of outstanding scientists present, but less so in terms of the total number of papers or citations. This study argues that indicators for the 1% high-citation tail of the citation distribution reveal the contribution of universities to the progress of science and provide quantifiable justification for the large investments in research made by elite research universities. In this tail, which follows a power low, the number of the less frequent and highly cited important breakthroughs can be predicted from the frequencies of papers in the upper part of the tail. This study quantifies the false impression of excellence produced by multinational papers, and by other types of papers that do not contribute to the progress of science. Many of these papers are concentrated in and dominate lists of highly cited papers, especially in lower-ranked universities. The h-index obscures the differences between higher- and lower-ranked universities because the proportion of h-core papers in the 1% high-citation tail is not proportional to the value of the h-index.
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Se analiza el absentismo, el fallo y el abandono de los estudiantes en los primeros semestres del grado sobre la base de su formación en la educación secundaria.
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During the first decade of the new millennium, fueled by the economic development in Spain, urban bus services were extended. Since the years 2008 and 2009, the root of the economic crisis, the improvement of these services is at risk due to economic problems. In this paper, the technical efficiency of the main urban bus companies in Spain during the 2004–2009 period are studied using SBM (slack-based measures) models and by establishing the slacks in the services' production inputs. The influence of a series of exogenous variables on the operation of the different services is also analyzed. It is concluded that only the 24% of the case studies are efficient, and some urban form variables can explain part of the inefficiency. The methodology used allows studying the inefficiency in a disaggregated way that other DEA (data envelopment analysis) models do not.