14,394 research outputs found

    A Reuse-based framework for the design of analog and mixed-signal ICs

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    Despite the spectacular breakthroughs of the semiconductor industry, the ability to design integrated circuits (ICs) under stringent time-to-market (TTM) requirements is lagging behind integration capacity, so far keeping pace with still valid Moore's Law. The resulting gap is threatening with slowing down such a phenomenal growth. The design community believes that it is only by means of powerful CAD tools and design methodologies -and, possibly, a design paradigm shift-that this design gap can be bridged. In this sense, reuse-based design is seen as a promising solution, and concepts such as IP Block, Virtual Component, and Design Reuse have become commonplace thanks to the significant advances in the digital arena. Unfortunately, the very nature of analog and mixed-signal (AMS) design has hindered a similar level of consensus and development. This paper presents a framework for the reuse-based design of AMS circuits. The framework is founded on three key elements: (1) a CAD-supported hierarchical design flow that facilitates the incorporation of AMS reusable blocks, reduces the overall design time, and expedites the management of increasing AMS design complexity; (2) a complete, clear definition of the AMS reusable block, structured into three separate facets or views: the behavioral, structural, and layout facets, the two first for top-down electrical synthesis and bottom-up verification, the latter used during bottom-up physical synthesis; (3) the design for reusability set of tools, methods, and guidelines that, relying on intensive parameterization as well as on design knowledge capture and encapsulation, allows to produce fully reusable AMS blocks. A case study and a functional silicon prototype demonstrate the validity of the paper's proposals.Ministerio de Educación y Ciencia TEC2004-0175

    Geometrically-constrained, parasitic-aware synthesis of analog ICs

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    In order to speed up the design process of analog ICs, iterations between different design stages should be avoided as much as possible. More specifically, spins between electrical and physical synthesis should be reduced for this is a very time-consuming task: if circuit performance including layout-induced degradations proves unacceptable, a re-design cycle must be entered, and electrical, physical, or both synthesis processes, would have to be repeated. It is also worth noting that if geometric optimization (e.g., area minimization) is undertaken after electrical synthesis, it may add up as another source of unexpected degradation of the circuit performance due to the impact of the geometric variables (e.g., transistor folds) on the device and the routing parasitic values. This awkward scenario is caused by the complete separation of said electrical and physical synthesis, a design practice commonly followed so far. Parasitic-aware synthesis, consisting in including parasitic estimates to the circuit netlist directly during electrical synthesis, has been proposed as solution. While most of the reported contributions either tackle parasitic-aware synthesis without paying special attention to geometric optimization or approach both issues only partially, this paper addresses the problem in a unified way. In what has been called layout-aware electrical synthesis, a simulation-based optimization algorithm explores the design space with geometric variables constrained to meet certain user-defined goals, which provides reliable estimates of layout-induced parasitics at each iteration, and, thereby, accurate evaluation of the circuit ultimate performance. This technique, demonstrated here through several design examples, requires knowing layout details beforehand; to facilitate this, procedural layout generation is used as physical synthesis approach due to its rapidness and ability to capture analog layout know-how.Ministerio de Educación y Ciencia TEC2004-0175

    On the suitability and development of layout templates for analog layout reuse and layout-aware synthesis

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    Accelerating the synthesis of increasingly complex analog integrated circuits is key to bridge the widening gap between what we can integrate and what we can design while meeting ever-tightening time-to-market constraints. It is a well-known fact in the semiconductor industry that such goal can only be attained by means of adequate CAD methodologies, techniques, and accompanying tools. This is particularly important in analog physical synthesis (a.k.a. layout generation), where large sensitivities of the circuit performances to the many subtle details of layout implementation (device matching, loading and coupling effects, reliability, and area features are of utmost importance to analog designers), render complete automation a truly challenging task. To approach the problem, two directions have been traditionally considered, knowledge-based and optimization-based, both with their own pros and cons. Besides, recently reported solutions oriented to speed up the overall design flow by means of reuse-based practices or by cutting off time-consuming, error-prone spins between electrical and layout synthesis (a technique known as layout-aware synthesis), rely on a outstandingly rapid yet efficient layout generation method. This paper analyses the suitability of procedural layout generation based on templates (a knowledge-based approach) by examining the requirements that both layout reuse and layout-aware solutions impose, and how layout templates face them. The ability to capture the know-how of experienced layout designers and the turnaround times for layout instancing are considered main comparative aspects in relation to other layout generation approaches. A discussion on the benefit-cost trade-off of using layout templates is also included. In addition to this analysis, the paper delves deeper into systematic techniques to develop fully reusable layout templates for analog circuits, either for a change of the circuit sizing (i.e., layout retargeting) or a change of the fabrication process (i.e., layout migration). Several examples implemented with the Cadence's Virtuoso tool suite are provided as demonstration of the paper's contributions.Ministerio de Educación y Ciencia TEC2004-0175

    Complementary music therapy for cancer patients in at-home palliative care and their caregivers: protocol for a multicentre randomised controlled trial

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    Background Patients with advanced cancer, receiving at-home palliative care, are subject to numerous symptoms that are changeable and often require attention, a stressful situation that also impacts on the family caregiver. It has been suggested that music therapy may benefit both the patient and the caregiver. We propose a study to analyse the efficacy and cost utility of a music intervention programme, applied as complementary therapy, for cancer patients in palliative care and for their at-home caregivers, compared to usual treatment. Method A randomised, double-blind, multicentre clinical trial will be performed in cancer patients in at-home palliative care and their family caregivers. The study population will include two samples of 40 patients and two samples of 41 caregivers. Participants will be randomly assigned either to the intervention group or to the control group. The intervention group will receive a seven-day programme including music sessions, while the control group will receive seven sessions of (spoken word) therapeutic education. In this study, the primary outcome measure is the assessment of patients' symptoms, according to the Edmonton Symptom Assessment System, and of the overload experienced by family caregivers, measured by the Caregiver Strain Index. The secondary outcomes considered will be the participants' health-related quality of life, their satisfaction with the intervention, and an economic valuation. Discussion This study is expected to enhance our understanding of the efficacy and cost-utility of music therapy for cancer patients in palliative care and for their family caregivers. The results of this project are expected to be applicable and transferrable to usual clinical practice for patients in home palliative care and for their caregivers. The approach described can be incorporated as an additional therapeutic resource within comprehensive palliative care. To our knowledge, no previous high quality studies, based on a double-blind clinical trial, have been undertaken to evaluate the cost-effectiveness of music therapy. The cost-effectiveness of the project will provide information to support decision making, thereby improving the management of health resources and their use within the health system

    Chemical Fingerprints in an Underwater Archaeological Shipwreck using a Remote Laser-Induced Breakdown Spectroscopy System

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    Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Sometimes extracting the archeological material from the marine environment is not practical due to the size of the sample, or is not permitted by the legislation or preservation practices. In these cases, the in-situ analysis turns into the only alternative. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography [1]. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. A fiber-optics-based remote instrument has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multipulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variefy of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In this work, parametric studies in the laboratory such as gas flow pressure, beam focal conditions and angle of incidence, among others, were performed to optimize the best conditions for field analysis. Finally, results obtained in these field trials confirmed the capability of remole LIBS for in-situ analysis of underwater archeological samples.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Libs in cultural heritage: recognition and identification of objects in an underwater archaeological shipwreck

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    Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Nevertheless, sometimes it is not possible to extract the archaeological material from the marine environment due to size of the sample, the legislation or preservation purposes. In these cases, the in-situ analysis turns into the only alternative for obtaining information. In spite of this demand, no analytical techniques are available for the in-situ chemical characterization of underwater materials. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. To further exploit the inherent advantages of the technology, a mobile fiber-based LIBS platform capable of performing remote measurements up to 50 meters range has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS) 2. The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In the present work, the design and construction considerations of the instrument are reported and its performance is discussed on the basis of the spectral response, the remote irradiance achieved upon the range of analysis and its influence on plasma properties, as well as the effect of the laser pulse duration and purge gas to the LIBS signal. Also, to check the reliability and reproducibility of the instrument for field analysis several robustness tests were performed outside the lab. Finally, the capability of this instrument was successfully demonstrated in an underwater archaeological shipwreck (San Pedro de Alcántara, Malaga).Universidad de Málaga. Campus de Excelencia Internacional Andalucí

    UCTx: a multi-agent system to assist a transplant coordination unit

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    We present a system called UCTx, designed to model and automate some of the tasks performed by a Transplant Coordination Unit (UCTx) inside a Hospital. The aim of this work is to show how a multi-agent approach allows us to describe and implement the model, and how UCTx is capable of dealing with another multi-agent (Carrel, an Agent Mediated Institution for the exchange of Human Tissues among Hospitals for Transplantation) in order to meet its own goals, acting as the representative of the hospital in the negotiation. As an example we introduce the use of this Agency in the case of Cornea Transplantation.Postprint (published version

    Remote Laser-Induced Breakdown Spectroscopy in Underwater Archaeology: Identification of Chemical Fingerprints in Shipwrecks

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    Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Sometimes extracting the archeological material from the marine environment is not practical due to the size of the sample, or is not permitted by the legislation or preservation practices. In these cases, the in-situ analysis turns into the only alternative. The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. A fiber-optics-based remote instrument has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In this work, parametric studies in the laboratory such as gas flow pressure, beam focal conditions and angle of incidence, among others, were performed to optimize the best conditions for field analysis. Finally, results obtained in these field trials confirmed the capability of remote LIBS for in-situ analysis of underwater archeological samples.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Cómo y en qué se gasta el presupuesto de la Administración de Justicia en España

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    En anteriores publicaciones pudimos concluir que el deficiente funcionamiento de la Administración de Justicia (AJ) en España obedece más a factores organizativos que a falta de presupuesto, destacando la confluencia de una elevada litigiosidad con una insuficiente planta de jueces, que, además, está mal distribuida territorialmente; y el hecho de que el incremento del gasto habido desde 2004 no ha mejorado su funcionamiento. Bajo estas premisas, el presente trabajo tiene como principal objetivo indagar a qué partidas se destina el gasto de la AJ, en un intento de aislar las razones que explicarían el por qué su incremento no se ha trasladado a su mejora. Para ello hemos tenido, en primer lugar, que reorganizar unas partidas presupuestarias dispersas entre los distintos Organismos que intervienen en la compleja organización judicial española. También hemos debido adoptar decisiones oportunamente justificadas acerca de qué partidas incluimos o no en los gastos, ya que no existen normas ni criteros reglados. Esto, a juicio de los autores, constituye un valor añadido al trabajo, al poner en conocimiento de la comunidad científica datos de díficil elboración

    El ayer, el hoy y el ay de la gestión de la Administración de Justicia en la Comunidad Autónoma de Andalucía

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    La Constitución Española dispuso en su artículo 149 que la Administración de Justicia (AJ) era competencia exclusiva del Estado, pero el Tribunal Constitucional distinguiendo entre Administración de Justicia, Poder Judicial (PJ), que no se puede transferir, y la administración de la Administración de Justicia, encargada de proveer de medios materiales y personales a la primera, que sí se puede transferir, conformó una AJ desconcentrada y descentralizada. La Comunidad Autónoma de Andalucía es una de las doce CCAA que tienen las competencias transferidas (RD 141 y 142) desde 1997. Puesto que hoy en día la AJ está siendo severamente cuestionada y desde numerosos sectores, tanto de los profesionales como de la ciudadanía general, abogan por un mayor gasto como vía de solución al mal funcionamiento, la presente investigación analiza si verdaderamente es esta la solución o si el problema radica fundamentalmente en que los recursos no se están utilizando con eficiencia. Aunque la incidencia de la gestión y del gasto de las CCAA en el funcionamiento de la AJ es relativa por cuanto no todo depende exclusivamente de ellas, sí es posible analizar la evolución del funcionamiento de los juzgados y tribunales en Andalucía desde 2004 y la comparación con el resto de CCAA. Para ello usamos tres grupos de indicadores: el gasto, los medios personales y la actividad jurisdiccional durante el periodo 2004-2015. Nuestros resultados muestran que, aunque la situación en Andalucía es dispar entre las distintas jurisdicciones, podemos afirmar un mayor deterioro del funcionamiento de la AJen el TSJA frente a otros TSJ.Esto se explica por la sobrecarga de trabajo de los jueces en Andalucía, que no ha paliado el aumento de gasto realizado en el periodo (50,2%). Así, el esfuerzo ha resultado ineficaz, al no incidir en las variables más condicionantes: número de jueces y litigiosidad
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