918 resultados para G520 Systems Design Methodologies
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Aplanatic designs present great interest in the optics field since they are free from spherical aberration and linear coma at the axial direction. Nevertheless nowadays it cannot be found on literature any thin aplanatic design based on a lens. This work presents the first aplanatic thin lens (in this case a dome-shaped faceted TIR lens performing light collimation), designed for LED illumination applications. This device, due to its TIR structure (defined as an anomalous microstructure as we will see) presents good color-mixing properties. We will show this by means of raytrace simulations, as well as high optical efficiency.
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LEDs are substituting fluorescent and incandescent bulbs as illumination sources due to their low power consumption and long lifetime. Visible Light Communications (VLC) makes use of the LEDs short switching times to transmit information. Although LEDs switching speed is around Mbps range, higher speeds (hundred of Mbps) can be reached by using high bandwidth-efficiency modulation techniques. However, the use of these techniques requires a more complex driver which elevates drastically its power consumption. In this work an energy efficiency analysis of the different VLC modulation techniques and drivers is presented. Besides, the design of new schemes of VLC drivers is described.
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Una de las dificultades principales en el desarrollo de software es la ausencia de un marco conceptual adecuado para su estudio. Una propuesta la constituye el modelo transformativo, que entiende el desarrollo de software como un proceso iterativo de transformación de especificaciones: se parte de una especificación inicial que va transformándose sucesivamente hasta obtener una especificación final que se toma como programa. Este modelo básico puede llevarse a la práctica de varias maneras. En concreto, la aproximación deductiva toma una sentencia lógica como especificación inicial y su proceso transformador consiste en la demostración de la sentencia; como producto secundario de la demostración se deriva un programa que satisface la especificación inicial. La tesis desarrolla un método deductivo para la derivación de programas funcionales con patrones, escritos en un lenguaje similar a Hope. El método utiliza una lógica multigénero, cuya relación con el lenguaje de programación es estudiada. También se identifican los esquemas de demostración necesarios para la derivación de funciones con patrones, basados en la demostración independiente de varias subsentencias. Cada subsentencia proporciona una subespecificación de una ecuación del futuro programa a derivar. Nuestro método deductivo está inspirado en uno previo de Zohar Manna y Richard Waldinger, conocido como el cuadro deductivo, que deriva programas en un lenguaje similar a Lisp. El nuevo método es una modificación del cuadro de estos autores, que incorpora géneros y permite demostrar una especificación mediante varios cuadros. Cada cuadro demuestra una subespecificación y por tanto deriva una ecuación del programa. Se prevén mecanismos para que los programas derivados puedan contener definiciones locales con patrones y variables anónimas y sinónimas y para que las funciones auxiliares derivadas no usen variables de las funciones principales. La tesis se completa con varios ejemplos de aplicación, un mecanismo que independentiza el método del lenguaje de programación y un prototipo de entorno interactivo de derivación deductiva. Categorías y descriptores de materia CR D.l.l [Técnicas de programación]: Programación funcional; D.2.10 [Ingeniería de software]: Diseño - métodos; F.3.1 [Lógica y significado de los programas]: Especificación, verificación y razonamiento sobre programas - lógica de programas; F.3.3 [Lógica y significado de los programas]: Estudios de construcciones de programas - construcciones funcionales; esquemas de programa y de recursion; 1.2.2 [Inteligencia artificial]: Programación automática - síntesis de programas; 1.2.3 [Inteligencia artificial]: Deducción y demostración de teoremas]: extracción de respuesta/razón; inducción matemática. Términos generales Programación funcional, síntesis de programas, demostración de teoremas. Otras palabras claves y expresiones Funciones con patrones, cuadro deductivo, especificación parcial, inducción estructural, teorema de descomposición.---ABSTRACT---One of the main difficulties in software development is the lack of an adequate conceptual framework of study. The transformational model is one such proposal that conceives software development as an iterative process of specifications transformation: an initial specification is developed and successively transformed until a final specification is obtained and taken as a program. This basic model can be implemented in several ways. The deductive approach takes a logical sentence as the initial specification and its proof constitutes the transformational process; as a byproduct of the proof, a program which satisfies the initial specification is derived. In the thesis, a deductive method for the derivation of Hope-like functional programs with patterns is developed. The method uses a many-sorted logic, whose relation to the programming language is studied. Also the proof schemes necessary for the derivation of functional programs with patterns, based on the independent proof of several subsentences, are identified. Each subsentence provides a subspecification of one equation of the future program to be derived. Our deductive method is inspired on a previous one by Zohar Manna and Richard Waldinger, known as the deductive tableau, which derives Lisp-like programs. The new method incorporates sorts in the tableau and allows to prove a sentence with several tableaux. Each tableau proves a subspecification and therefore derives an equation of the program. Mechanisms are included to allow the derived programs to contain local definitions with patterns and anonymous and synonymous variables; also, the derived auxiliary functions cannot reference parameters of their main functions. The thesis is completed with several application examples, i mechanism to make the method independent from the programming language and an interactive environment prototype for deductive derivation. CR categories and subject descriptors D.l.l [Programming techniques]: Functional programming; D.2.10 [Software engineering]: Design - methodologies; F.3.1 [Logics and meanings of programa]: Specifying and verifying and reasoning about programs - logics of programs; F.3.3 [Logics and meanings of programs]: Studies of program constructs - functional constructs; program and recursion schemes; 1.2.2 [Artificial intelligence]: Automatic programming - program synthesis; 1.2.3 [Artificial intelligence]: Deduction and theorem proving - answer/reason extraction; mathematical induction. General tenas Functional programming, program synthesis, theorem proving. Additional key words and phrases Functions with patterns, deductive tableau, structural induction, partial specification, descomposition theorem.
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Las personas con discapacidad a menudo se encuentran con problemas de acceso a las Tecnologías de la Información y la Comunicación (TIC), debido a diseños y desarrollos que no tienen en cuenta sus diferencias funcionales, y en consecuencia se encuentran en riesgo de exclusión social. Cada vez es más común encontrar productos de apoyo que permitan utilizar diferentes tecnologías (ordenadores, Internet, dispositivos móviles), pero muchos de ellos no se encuentran integrados debido a que funcionan esencialmente modificando la plataforma donde están instalados, siendo soluciones de acceso de segunda generación. Más allá del desarrollo de los productos de apoyo, que sin duda ha evolucionado positivamente en los últimos años, cabe resaltar que existe una falta de herramientas y de aproximación holística que ayuden a los desarrolladores y diseñadores hacer las TIC accesibles. Esta tesis doctoral pretende validar la hipótesis de que una metodología holística de desarrollo de aplicaciones y productos de apoyo TIC, llamada Marco Abierto Accesible, facilita el desarrollo y la integración de modo nativo de la accesibilidad en las aplicaciones y productos apoyo, independientemente de la tecnología utilizada, dando lugar a soluciones de acceso de tercera generación que permitan mejorar la utilización de dichas aplicaciones por parte de personas con discapacidad. Este trabajo se ha desarrollado en el marco del proyecto AEGIS (del inglés, open Accessibility Everywhere: Groundwork, Infrastructure, Standards), que fue parcialmente financiado por la Comisión Europea (CE) bajo el VII Programa Marco y tuvo una duración de cuatro años. La metodología para el diseño, desarrollo y validación seguida en esta tesis es una adaptación de dos metodologías de diseño existentes (el Diseño Centrado en el Usuario y el Diseño Orientado a Metas), la implementación del Marco Abierto Accesible y el uso de diferentes técnicas de validación. Además se ha desarrollado un marco metodológico de entrenamiento para minimizar el efecto que tiene la curva de aprendizaje cuando los usuarios prueban por primera vez las soluciones desarrolladas. En esta tesis se presenta el Marco Abierto Accesible aplicado a las TIC en las tres áreas en las que se desarrolla este trabajo: ordenadores, Internet y dispositivos móviles, partiendo de las necesidades y problemas que tienen los usuarios con discapacidad en el uso de las TIC. Diferentes instanciaciones del Marco Abierto Accesible se definen en las tres áreas TIC mencionadas anteriormente y se describen varios ejemplos de sus implementaciones particulares. Los resultados de las evaluaciones de las implementaciones particulares con usuarios finales y expertos, una vez discutidos y contrastados con las hipótesis, sirven para probar la validez del Marco Abierto Accesible para la integración nativa de productos de apoyo en Tecnologías de la Información y la Comunicación. Finalmente, se presentan las líneas de investigación y trabajo futuro en el área de la accesibilidad en las TIC. ABSTRACT People with disabilities often encounter problems of access to Information and Communications Technology (ICT), due to design and developments that do not take into account their functional differences and therefore put them at risk of social exclusion. It is increasingly common to find assistive products that allow to use different technologies (computers, Internet, mobile devices), but many of them are not well integrated because they work essentially modifying the platform where they are installed, beeing the second-generation access solutions. Beyond the assistive product development, which has certainly evolved positively in recent years, it is notable that there is a lack of tools and holistic approach to help developers and designers make accessible ICT. This doctoral thesis aims to validate the hypothesis that a holistic approach to application development and assistive ICT products, called Open Accessibility Framework, facilitates the development and integration of native accessible applications and assistive products, regardless of the technology used, resulting in third-generation access solutions that improve the use of such applications by people with disabilities. This work was developed under the AEGIS project (open Accessibility Everywhere: Groundwork, Infrastructure, Standards), which was partially funded by the European Commission (EC) under the Seventh Framework Programme and lasted four years. The methodology for the design, development and validation followed in this thesis is an adaptation of two existing design methodologies (User Centered Design and Goal Oriented Design), the implementation of the Open Accessibility Framework and the usage of different validation techniques. A training methodological framework ha also been developed to minimize the effect of the learning curve when users first try the solutions developed. This thesis presents the Open Accessibility Framework applied to ICT in three areas in which this work is developed: computers, Internet and mobile devices, based on the needs and problems of the disabled users in the use of ICT. Different instantiations of the Open Accessibility Framework are defined in the three aforementioned ICT areas and various examples of its particular implementations are described. The results of the evaluations of the particular implementations which have been carried with end users and experts, once discussed and contrasted with the hypotheses, have been used to test the validity of the Open Accessibility Framework for the native integration of assistive products in Information and Communications Technology. Finally, the future research lines and future work in the area of ICT accessibility are presented.
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The role of matter has remained central to the making and the thinking of architecture, yet many attempts to capture its essence have been trapped in a dialectic tension between form and materiality, between material consistency and immaterial modes of perception, between static states and dynamic processes, between the real and the virtual, thus advancing an increasing awareness of the perplexing complexity of the material world. Within that complexity, the notion of agency – emerging from and within ecological, politico-economic and socio-cultural processes – calls for a reconceptualization of matter, and consequently processes of materialisation, offering a new understanding of context and space, approached as a field of dynamic relationships. In this context, cutting across boundaries between architectural discourse and practice as well as across the vast trans-disciplinary territory, this dissertation aims to illustrate a variety of design methodologies that have derived from the relational approach. More specifically, the intention is to offer new insights into spatial epistemologies embedded within the notion of atmosphere – commonly associated with the so-called New Phenomenology – and to reflect upon its implications for architectural production. In what follows, the intended argumentation has a twofold dimension. First, through a scrutiny of the notion of atmosphere, the aim is to explore ways of thinking and shaping reality through relations, thus acknowledging the aforementioned complexity of the material universe disclosed through human and non-human as well as material and immaterial forces. Secondly, despite the fact that concerns for atmospherics have flourished over the last few decades, the objective is to reveal that the conceptual foundations and procedures for the production of atmosphere might be found beneath the surface of contemporary debates. Hence, in order to unfold and illustrate previously advocated assumptions, an archaeological approach is adopted, tracing a particular projective genealogy, one that builds upon an atmospheric awareness. Accordingly, in tracing such an atmospheric awareness the study explores the notoriously ambiguous nature and the twofold dimension of atmosphere – meteorological and aesthetic – and the heterogeneity of meanings embedded in them. In this context, the notion of atmosphere is presented as parallactic. It transgresses the formal and material boundaries of bodies. It calls for a reevaluation of perceptual experience, opening a new gap that exposes the orthodox space-bodyenvironment relationships to questioning. It offers to architecture an expanded domain in which to manifest itself, defining architectural space as a contingent construction and field of engagement, and presenting matter as a locus of production/performance/action. Consequently, it is such an expanded or relational dimension that constitutes the foundation of what in the context of this study is to be referred to as affective tectonics. Namely, a tectonics that represents processual and experiential multiplicity of convergent time and space, body and environment, the material and the immaterial; a tectonics in which matter neither appears as an inert and passive substance, nor is limited to the traditionally regarded tectonic significance or expressive values, but is presented as an active element charged with inherent potential and vitality. By defining such a relational materialism, the intention is to expand the spectrum of material attributes revealing the intrinsic relationships between the physical properties of materials and their performative, transformative and affective capacities, including effects of interference and haptic dynamics – i.e. protocols of transmission and interaction. The expression that encapsulates its essence is: ACTIVE MATERIALITY RESUMEN El significado de la materia ha estado desde siempre ligado al pensamiento y el quehacer arquitectónico. Sin embargo, muchos intentos de capturar su esencia se han visto sumergidos en una tensión dialéctica entre la forma y la materialidad, entre la consistencia material y los modos inmateriales de la percepción, entre los estados estáticos y los procesos dinámicos, entre lo real y lo virtual, revelando una creciente conciencia de la desconcertante complejidad del mundo material. En esta complejidad, la noción de la operatividad o capacidad agencial– que emerge desde y dentro de los procesos ecológicos, políticos y socio-culturales– requiere de una reconceptualización de la materia y los procesos inherentes a la materialización, ofreciendo una nueva visión del contexto y el espacio, entendidos como un campo relacional dinámico. Oscilando entre el discurso arquitectónico y la práctica arquitectónica, y atravesando un extenso territorio trans-disciplinar, el objetivo de la presente tesis es ilustrar la variedad de metodologías proyectuales que emergieron desde este enfoque relacional. Concretamente, la intención es indagar en las epistemologías espaciales vinculadas a la noción de la atmósfera– generalmente asociada a la llamada Nueva Fenomenología–, reflexionando sobre su impacto en la producción arquitectónica. A continuación, el estudio ofrece una doble línea argumental. Primero, a través del análisis crítico de la noción de atmósfera, el objetivo es explorar maneras de pensar y dar forma a la realidad a través de las relaciones, reconociendo la mencionada complejidad del universo material revelado a través de fuerzas humanas y no-humanas, materiales e inmateriales. Segundo, a pesar de que el interés por las atmósferas ha florecido en las últimas décadas, la intención es demostrar que las bases conceptuales y los protocolos proyectuales de la creación de atmósferas se pueden encontrar bajo la superficie de los debates contemporáneos. Para corroborar e ilustrar estas hipótesis se propone una metodología de carácter arqueológico, trazando una particular genealogía de proyectos– la que se basa en una conciencia atmosférica. Asimismo, al definir esta conciencia atmosférica, el estudio explora tanto la naturaleza notoriamente ambigua y la dimensión dual de la atmósfera– meteorológica y estética–, como la heterogeneidad de significados derivados de ellas. En este contexto, la atmósfera se entiende como un concepto detonante, ya que sobrepasa los limites formales y materiales de los cuerpos, llevando a la re-evaluación de la experiencia perceptiva y abriendo a preguntas la ortodoxa relación espacio- cuerpo-ambiente. En consecuencia, la noción de la atmósfera ofrece a la arquitectura una dimensión expandida donde manifestarse, definiendo el espacio como una construcción contingente, performativa y afectiva, y presentando la materia como locus de producción/ actuación/ acción. Es precisamente esta dimensión expandida relacional la que constituye una base para lo que en el contexto del presente estudio se define como una tectónica afectiva. Es decir, una tectónica que representa una multiplicidad procesual y experiencial derivada de la convergencia entre el tiempo y el espacio, el cuerpo y el entorno, lo material y lo inmaterial; una tectónica en la que la materia no aparece como una substancia pasiva e inerte, ni es limitada al significado considerado tradicionalmente constructivo o a sus valores expresivos, sino que se presenta como elemento activo cargado de un potencial y vitalidad inherentes. A través de la definición de este tipo de materialismo afectivo, la intención es expandir el espectro de los atributos materiales, revelando las relaciones intrínsecas entre las propiedades físicas de los materiales y sus capacidades performativas, transformativas y afectivas, incluyendo efectos de interferencias y dinámicas hápticas– o dicho de otro modo, protocolos de transmisión e interacción. Una expresión que encapsula su esencia vendría a ser: MATERIALIDAD ACTIVA
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These days as we are facing extremely powerful attacks on servers over the Internet (say, by the Advanced Persistent Threat attackers or by Surveillance by powerful adversary), Shamir has claimed that “Cryptography is Ineffective”and some understood it as “Cryptography is Dead!” In this talk I will discuss the implications on cryptographic systems design while facing such strong adversaries. Is crypto dead or we need to design it better, taking into account, mathematical constraints, but also systems vulnerability constraints. Can crypto be effective at all when your computer or your cloud is penetrated? What is lost and what can be saved? These are very basic issues at this point of time, when we are facing potential loss of privacy and security.
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Paper submitted to Euromicro Symposium on Digital Systems Design (DSD), Belek-Antalya, Turkey, 2003.
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This qualitative study focuses on what contributes to making a music information-seeking experience satisfying in the context of everyday life. Data were collected through in-depth interviews conducted with 15 younger adults (18 to 29 years old). The analysis revealed that satisfaction could depend on both hedonic (i.e., experiencing pleasure) and utilitarian outcomes. It was found that two types of utilitarian outcomes contributed to satisfaction: (1) the acquisition of music, and (2) the acquisition of information about music. Information about music was gathered to (1) enrich the listening experience, (2) increase one's music knowledge, and/or (3) optimize future acquisition. This study contributes to a better understanding of music information-seeking behavior in recreational contexts. It also has implications for music information retrieval systems design: results suggest that these systems should be engaging, include a wealth of extra-musical information, allow users to navigate among music items, and encourage serendipitous encountering of music.
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This paper proposes to build on previous research on the use of real options in strategic decision making (Carayannis and Sipp, 2010) and instill some real options-related concepts stemming from systems design, more particularly engineering. It also builds on previously-established concepts of strategic knowledge serendipity and arbitrage and strategic knowledge co-opetition, co-evolution and co-specialization developed by Carayannis (2009). The application of real options “in” system and real options to innovation and innovation policies demonstrate how embedded real options can more effectively be identified and therefore the decision to execute them or not more effectively made.
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This qualitative study focuses on what contributes to making a music information-seeking experience satisfying in the context of everyday life. Data were collected through in-depth interviews conducted with 15 younger adults (18 to 29 years old). The analysis revealed that satisfaction could depend on both hedonic (i.e., experiencing pleasure) and utilitarian outcomes. It was found that two types of utilitarian outcomes contributed to satisfaction: (1) the acquisition of music, and (2) the acquisition of information about music. Information about music was gathered to (1) enrich the listening experience, (2) increase one's music knowledge, and/or (3) optimize future acquisition. This study contributes to a better understanding of music information-seeking behavior in recreational contexts. It also has implications for music information retrieval systems design: results suggest that these systems should be engaging, include a wealth of extra-musical information, allow users to navigate among music items, and encourage serendipitous encountering of music.
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Texas Department of Transportation, Austin
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Transportation Systems Center, Cambridge, Mass.
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Federal Highway Administration, Office of Research, Washington, D.C.
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Transportation Systems Center, Cambridge, Mass.
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Mode of access: Internet.