Rapid prototyping of multi-scale biomedical microdevices by combining additive manufacturing technologies

The possibility of designing and manufacturing biomedical microdevices with multiple length-scale geometries can help to promote special interactions both with their environment and with surrounding biological systems. These interactions aim to enhance biocompatibility and overall performance by using biomimetic approaches. In this paper, we present a design and manufacturing procedure for obtaining multi-scale biomedical microsystems based on the combination of two additive manufacturing processes: a conventional laser writer to manufacture the overall device structure, and a direct-laser writer based on two-photon polymerization to yield finer details. The process excels for its versatility, accuracy and manufacturing speed and allows for the manufacture of microsystems and implants with overall sizes up to several millimeters and with details down to sub-micrometric structures. As an application example we have focused on manufacturing a biomedical microsystem to analyze the impact of microtextured surfaces on cell motility. This process yielded a relevant increase in precision and manufacturing speed when compared with more conventional rapid prototyping procedures.

Design and implementation of a modular interface to integrate CLP and tabled execution

Logic programming (LP) is a family of high-level programming languages which provides high expressive power. With LP, the programmer writes the properties of the result and / or executable specifications instead of detailed computation steps. Logic programming systems which feature tabled execution and constraint logic programming have been shown to increase the declarativeness and efficiency of Prolog, while at the same time making it possible to write very expressive programs. Tabled execution avoids infinite failure in some cases, while improving efficiency in programs which repeat computations. CLP reduces the search tree and brings the power of solving (in)equations over arbitrary domains. Similarly to the LP case, CLP systems can also benefit from the power of tabling. Previous implementations which take ful advantage of the ideas behind tabling (e.g., forcing suspension, answer subsumption, etc. wherever it is necessary to avoid recomputation and terminate whenever possible) did not offer a simple, well-documented, easy-to-understand interface. This would be necessary to make the integratation of arbitrary CLP solvers into existing tabling systems possible. This clearly hinders a more widespread usage of the combination of both facilities. In this thesis we examine the requirements that a constraint solver must fulfill in order to be interfaced with a tabling system. We propose and implement a framework, which we have called Mod TCLP, with a minimal set of operations (e.g., entailment checking and projection) which the constraint solver has to provide to the tabling engine. We validate the design of Mod TCLP by a series of use cases: we re-engineer a previously existing tabled constrain domain (difference constraints) which was connected in an ad-hoc manner with the tabling engine in Ciao Prolog; we integrateHolzbauer���s CLP(Q) implementationwith Ciao Prolog���s tabling engine; and we implement a constraint solver over (finite) lattices. We evaluate its performance with several benchmarks that implement a simple abstract interpreter whose fixpoint is reached by means of tabled execution, and whose domain operations are handled by the constraint over (finite) lattices, where TCLP avoids recomputing subsumed abstractions.---ABSTRACT---La programaci��n l��gica con restricciones (CLP) y la tabulaci��n son extensiones de la programaci��n l��gica que incrementan la declaratividad y eficiencia de Prolog, al mismo tiempo que hacen posible escribir programasm��s expresivos. Las implementaciones anteriores que integran completamente ambas extensiones, incluyendo la suspensi��n de la ejecuci��n de objetivos siempre que sea necesario, la implementaci��n de inclusi��n (subsumption) de respuestas, etc., en todos los puntos en los que sea necesario para evitar recomputaciones y garantizar la terminaci��n cuando sea posible, no han proporcionan una interfaz simple, bien documentada y f��cil de entender. Esta interfaz es necesaria para permitir integrar resolutores de CLP arbitrarios en el sistema de tabulaci��n. Esto claramente dificulta un uso m��s generalizado de la integraci��n de ambas extensiones. En esta tesis examinamos los requisitos que un resolutor de restricciones debe cumplir para ser integrado con un sistema de tabulaci��n. Proponemos un esquema (y su implementaci��n), que hemos llamadoMod TCLP, que requiere un reducido conjunto de operaciones (en particular, y entre otras, entailment y proyecci��n de almacenes de restricciones) que el resolutor de restricciones debe ofrecer al sistema de tabulaci��n. Hemos validado el dise��o de Mod TCLP con una serie de casos de uso: la refactorizaci��n de un sistema de restricciones (difference constraints) previamente conectado de un modo ad-hoc con la tabulaci��n de Ciao Prolog; la integraci��n del sistema de restricciones CLP(Q) de Holzbauer; y la implementaci��n de un resolutor de restricciones sobre ret��culos finitos. Hemos evaluado su rendimiento con varios programas de prueba, incluyendo la implementaci��n de un int��rprete abstracto que alcanza su punto fijo mediante el sistema de tabulaci��n y en el que las operaciones en el dominio son realizadas por el resolutor de restricciones sobre ret��culos (finitos) donde TCLP evita la recomputaci��n de valores abstractos de las variables ya contenidos en llamadas anteriores.

Sobre el comportamiento de micropilotes trabajando a flexi��n y/o cortante en estructuras de tierra

El empleo de los micropilotes en la ingenier��a civil ha revolucionado las t��cnicas de estabilizaci��n de terraplenes a media ladera, ya que aunque los pilotes pueden ser la opci��n m��s econ��mica, el uso de micropilotes permite llegar a sitios inaccesibles con menor coste de movimientos de tierras, realizaci��n de plataformas de trabajo de dimensiones reducidas, maquinaria necesaria es mucho m��s peque��a, liviana y vers��til en su uso, incluyendo la posibilidad de situar la fabricaci��n de morteros o lechadas a distancias de varias decenas de metros del elemento a ejecutar. Sin embargo, realizando una revisi��n de la documentaci��n t��cnica que se tiene en el ��mbito ingenieril, se comprob�� que los sistemas de dise��o de algunos casos (micropilotes en terraplenes a media ladera, micropilotes en pantallas verticales, micropilotes como ���paraguas��� en t��neles, etc.) eran bastante deficientes o poco desarrollados. Premisa que permite concluir que el constructor ha ido por delante (como suele ocurrir en ingenier��a geot��cnica) del c��lculo o de su an��lisis te��rico. Del mismo modo se determin�� que en su mayor��a los micropilotes se utilizan en labores de recalce o como nueva soluci��n de cimentaci��n en condiciones de dif��cil acceso, casos en los que el dise��o de los micropilotes viene definido por cargas axiales, de compresi��n o de tracci��n, consideraciones que se contemplan en reglamentaciones como la ���Gu��a para el proyecto y la ejecuci��n de micropilotes en obras de carretera��� del Ministerio de Fomento. En los micropilotes utilizados para estabilizar terraplenes a media ladera y micropilotes actuando como muros pantalla, en los que ��stos trabajan a esfuerzo cortante y flexi��n, no se dispone de sistemas de an��lisis fiables o no se introduce adecuadamente el problema de interacci��n terreno-micropilote. Adem��s en muchos casos, los par��metros geot��cnicos que se utilizan no tienen una base t��cnico-te��rica adecuada por lo que los dise��os pueden quedar excesivamente del lado de la seguridad, en la mayor��a de los casos, o todo lo contrario. Uno de los objetivos principales de esta investigaci��n es estudiar el comportamiento de los micropilotes que est��n sometidos a esfuerzos de flexi��n y cortante, adem��s de otros objetivos de gran importancia que se describen en el apartado correspondiente de esta tesis. Cabe indicar que en este estudio no se ha incluido el caso de micropilotes quasi-horizontales trabajando a flexion (como los ���paraguas��� en t��neles), por considerarse que estos tienen un comportamiento y un c��lculo diferente, que est�� fuera del alcance de esta investigaci��n. Se ha profundizado en el estudio del empleo de micropilotes en taludes, presentando casos reales de obras ejecutadas, datos estad��sticos, problemas de dise��o y ejecuci��n, m��todos de c��lculo simplificados y modelaci��n te��rica en cada caso, efectuada mediante el empleo de elementos finitos con el C��digo Plaxis 2D. Para llevar a cabo los objetivos que se buscan con esta investigaci��n, se ha iniciado con el desarrollo del ���Estado del Arte��� que ha permitido establecer tipolog��a, aplicaciones, caracter��sticas y c��lculo de los micropilotes que se emplean habitualmente. Seguidamente y a efectos de estudiar el problema dentro de un marco geot��cnico real, se ha seleccionado una zona espa��ola de actuaci��n, siendo ��sta Andaluc��a, en la que se ha utilizado de manera muy importante la t��cnica de micropilotes sobre todo en problemas de estabilidad de terraplenes a media ladera. A partir de ah��, se ha realizado un estudio de las propiedades geot��cnicas de los materiales (principalmente suelos y rocas muy blandas) que est��n presentes en esta zona geogr��fica, estudio que ha sido principalmente bibliogr��fico o a partir de la experiencia en la zona del Director de esta tesis. Del an��lisis realizado se han establecido ordenes de magnitud de los par��metros geot��cnicos, principalmente la cohesi��n y el ��ngulo de rozamiento interno (adem��s del m��dulo de deformaci��n aparente o de un m��dulo de reacci��n lateral equivalente) para los diversos terrenos andaluces. Con el objeto de conocer el efecto de la ejecuci��n de un micropilote en el terreno (volumen medio real del micropilote, una vez ejecutado; efecto de la presi��n aplicada en las propiedades del suelo circundante, etc.) se ha realizado una encuesta entre diversas empresas espa��olas especializadas en la t��cnica de los micropilotes, a efectos de controlar los vol��menes de inyecci��n y las presiones aplicadas, en funci��n de la deformabilidad del terreno circundante a dichos micropilotes, con lo que se ha logrado definir una rigidez a flexi��n equivalente de los mismos y la definici��n y caracter��sticas de una corona de terreno ���mejorado��� lograda mediante la introducci��n de la lechada y el efecto de la presi��n alrededor del micropilote. Con las premisas anteriores y a partir de los par��metros geot��cnicos determinados para los terrenos andaluces, se ha procedido a estudiar la estabilidad de terraplenes apoyados sobre taludes a media ladera, mediante el uso de elementos finitos con el C��digo Plaxis 2D. En el cap��tulo 5. ���Simulaci��n del comportamiento de micropilotes estabilizando terraplenes���, se han desarrollado diversas simulaciones. Para empezar se simplific�� el problema simulando casos similares a algunos reales en los que se conoc��a que los terraplenes hab��an llegado hasta su situaci��n l��mite (de los que se dispon��a informaci��n de movimientos medidos con inclin��metros), a partir de ah�� se inici�� la simulaci��n de la inestabilidad para establecer el valor de los par��metros de resistencia al corte del terreno (mediante un an��lisis retrospectivo ��� back-an��lisis) comprobando a su vez que estos valores eran similares a los deducidos del estudio bibliogr��fico. Seguidamente se han introducido los micropilotes en el borde de la carretera y se ha analizado el comportamiento de ��stos y del talud del terrapl��n (una vez construidos los micropilotes), con el objeto de establecer las bases para su dise��o. De este modo y adoptando los distintos par��metros geot��cnicos establecidos para los terrenos andaluces, se simularon tres casos reales (en Granada, M��laga y Ceuta), comparando los resultados de dichas simulaciones num��ricas con los resultados de medidas reales de campo (desplazamientos del terreno, medidos con inclin��metros), obteni��ndose una reproducci��n bastante acorde a los movimientos registrados. Con las primeras simulaciones se concluye que al instalar los micropilotes la zona m��s insegura de la ladera es la de aguas abajo. La superficie de rotura ya no afecta a la calzada que protegen los micropilotes. De ah�� que se deduzca que esta soluci��n sea v��lida y se haya aplicado masivamente en Andaluc��a. En esas condiciones, podr��a decirse que no se est�� simulando adecuadamente el trabajo de flexi��n de los micropilotes (en la superficie de rotura, ya que no les corta), aunque se utilicen elementos viga. Por esta raz��n se ha realizado otra simulaci��n, basada en las siguientes hip��tesis: ��� Se desprecia totalmente la masa potencialmente deslizante, es decir, la que est�� por delante de la fila exterior de micros. ��� La estratigraf��a del terreno es similar a la considerada en las primeras simulaciones. ��� La barrera de micropilotes est�� constituida por dos elementos inclinados (uno hacia dentro del terrapl��n y otro hacia fuera), con inclinaci��n 1(H):3(V). ��� Se puede introducir la rigidez del encepado. ��� Los micros est��n separados 0,556 m �� 1,00 m dentro de la misma alineaci��n. ��� El empotramiento de los micropilotes en el sustrato resistente puede ser entre 1,5 y 7,0 m. Al ���anular��� el terreno que est�� por delante de los micropilotes, a lo largo del talud, estos elementos empiezan claramente a trabajar, pudiendo deducirse los esfuerzos de cortante y de flexi��n que puedan actuar sobre ellos (cota superior pero pr��cticamente muy cerca de la soluci��n real). En esta nueva modelaci��n se ha considerado tanto la rigidez equivalente (coeficiente ��) como la corona de terreno tratado conc��ntrico al micropilote. De acuerdo a esto ��ltimo, y gracias a la comparaci��n de estas modelaciones con valores reales de movimientos en laderas instrumentadas con problemas de estabilidad, se ha verificado que existe una similitud bastante importante entre los valores te��ricos obtenidos y los medidos en campo, en relaci��n al comportamiento de los micropilotes ejecutados en terraplenes a media ladera. Finalmente para completar el an��lisis de los micropilotes trabajando a flexi��n, se ha estudiado el caso de micropilotes dispuestos verticalmente, trabajando como pantallas discontinuas provistas de anclajes, aplicado a un caso real en la ciudad de Granada, en la obra ���Hospital de Nuestra Se��ora de la Salud���. Para su an��lisis se utiliz�� el c��digo num��rico CYPE, basado en que la reacci��n del terreno se simula con muelles de rigidez Kh o ���m��dulo de balasto��� horizontal, introduciendo en la modelaci��n como variables: a) Las diferentes medidas obtenidas en campo; b) El espesor de terreno cuaternario, que por lo que se pudo determinar, era variable, c) La rigidez y tensi��n inicial de los anclajes. d) La rigidez del terreno a trav��s de valores relativos de Kh, recopilados en el estudio de los suelos de Andaluc��a, concretamente en la zona de Granada. Dicha pantalla se instrument�� con 4 inclin��metros (introducidos en los tubos de armadura de cuatro micropilotes), a efectos de controlar los desplazamientos horizontales del muro de contenci��n durante las excavaciones pertinentes, a efectos de comprobar la seguridad del conjunto. A partir del modelo de c��lculo desarrollado, se ha comprobado que el valor de Kh pierde importancia debido al gran n��mero de niveles de anclajes, en lo concerniente a las deformaciones horizontales de la pantalla. Por otro lado, los momentos flectores son bastante sensibles a la distancia entre anclajes, al valor de la tensi��n inicial de los mismos y al valor de Kh. Dicho modelo tambi��n ha permitido reproducir de manera fiable los valores de desplazamientos medidos en campo y deducir los par��metros de deformabilidad del terreno, Kh, con valores del orden de la mitad de los medidos en el Metro Ligero de Granada, pero visiblemente superiores a los deducibles de ��bacos que permiten obtener Kh para suelos granulares con poca cohesi��n (gravas y cuaternario superior de Sevilla) como es el caso del ��baco de Arozamena, debido, a nuestro juicio, a la cementaci��n de los materiales presentes en Granada. En definitiva, de las anteriores deducciones se podr��a pensar en la optimizaci��n del dise��o de los micropilotes en las obras que se prevean ejecutar en Granada, con similares caracter��sticas al caso de la pantalla vertical arriostrada mediante varios niveles de anclajes y en las que los materiales de emplazamiento tengan un comportamiento geot��cnico similar a los estudiados, con el consiguiente ahorro econ��mico. Con todo ello, se considera que se ha hecho una importante aportaci��n para el dise��o de futuras obras de micropilotes, trabajando a flexi��n y cortante, en obras de estabilizaci��n de laderas o de excavaciones. Using micropiles in civil engineering has transformed the techniques of stabilization of embankments on the natural or artificial slopes, because although the piles may be the cheapest option, the use of micropiles can reach inaccessible places with lower cost of earthworks, carrying out small work platforms. Machinery used is smaller, lightweight and versatile, including the possibility of manufacturing mortars or cement grouts over distances of several tens of meters of the element to build. However, making a review of the technical documentation available in the engineering field, it was found that systems designed in some cases (micropiles in embankments on the natural slopes, micropiles in vertical cut-off walls, micropiles like "umbrella" in tunnels, etc.) were quite poor or underdeveloped. Premise that concludes the builder has gone ahead (as usually happen in geotechnical engineering) of calculation or theoretical analysis. In the same way it was determined that most of the micropiles are used in underpinning works or as a new foundation solution in conditions of difficult access, in which case the design of micropiles is defined by axial, compressive or tensile loads, considered in regulations as the " Handbook for the design and execution of micropiles in road construction" of the Ministry of Development. The micropiles used to stabilize embankments on the slopes and micropiles act as retaining walls, where they work under shear stress and bending moment, there are not neither reliable systems analysis nor the problem of soil-micropile interaction are properly introduced. Moreover, in many cases, the geotechnical parameters used do not have a proper technical and theoretical basis for what designs may be excessively safe, or the opposite, in most cases. One of the main objectives of this research is to study the behavior of micro piles which are subjected to bending moment and shear stress, as well as other important objectives described in the pertinent section of this thesis. It should be noted that this study has not included the case of quasi-horizontal micropiles working bending moment (as the "umbrella" in tunnels), because it is considered they have a different behavior and calculation, which is outside the scope of this research. It has gone in depth in the study of using micropiles on slopes, presenting real cases of works made, statistics, problems of design and implementation, simplified calculation methods and theoretical modeling in each case, carried out by using FEM (Finite Element Method) Code Plaxis 2D. To accomplish the objectives of this research, It has been started with the development of the "state of the art" which stipulate types, applications, characteristics and calculation of micropiles that are commonly used. In order to study the problem in a real geotechnical field, it has been selected a Spanish zone of action, this being Andalusia, in which it has been used in a very important way, the technique of micropiles especially in embankments stability on natural slopes. From there, it has made a study of the geotechnical properties of the materials (mainly very soft soils and rocks) that are found in this geographical area, which has been mainly a bibliographic study or from the experience in the area of the Director of this thesis. It has been set orders of magnitude of the geotechnical parameters from analyzing made, especially the cohesion and angle of internal friction (also apparent deformation module or a side reaction module equivalent) for various typical Andalusian ground. In order to determine the effect of the implementation of a micropile on the ground (real average volume of micropile once carried out, effect of the pressure applied on the properties of the surrounding soil, etc.) it has conducted a survey among various skilled companies in the technique of micropiles, in order to control injection volumes and pressures applied, depending on the deformability of surrounding terrain such micropiles, whereby it has been possible to define a bending stiffness and the definition and characteristics of a crown land "improved" achieved by introducing the slurry and the effect of the pressure around the micropile. With the previous premises and from the geotechnical parameters determined for the Andalusian terrain, we proceeded to study the stability of embankments resting on batters on the slope, using FEM Code Plaxis 2D. In the fifth chapter "Simulation of the behavior of micropiles stabilizing embankments", there were several different numerical simulations. To begin the problem was simplified simulating similar to some real in which it was known that the embankments had reached their limit situation (for which information of movements measured with inclinometers were available), from there the simulation of instability is initiated to set the value of the shear strength parameters of the ground (by a retrospective analysis or back-analysis) checking these values were similar to those deduced from the bibliographical study Then micropiles have been introduced along the roadside and its behavior was analyzed as well as the slope of embankment (once micropiles were built ), in order to establish the basis for its design. In this way and taking the different geotechnical parameters for the Andalusian terrain, three real cases (in Granada, Malaga and Ceuta) were simulated by comparing the results of these numerical simulations with the results of real field measurements (ground displacements measured with inclinometers), getting quite consistent information according to registered movements. After the first simulations it has been concluded that after installing the micropiles the most insecure area of the natural slope is the downstream. The failure surface no longer affects the road that protects micropiles. Hence it is inferred that this solution is acceptable and it has been massively applied in Andalusia. Under these conditions, one could say that it is not working properly simulating the bending moment of micropiles (on the failure surface, and that does not cut them), although beam elements are used. Therefore another simulation was performed based on the following hypotheses: ��� The potentially sliding mass is totally neglected, that is, which is ahead of the outer row of micropiles. ��� Stratigraphy field is similar to the one considered in the first simulations. ��� Micropiles barrier is constituted by two inclined elements (one inward and one fill out) with inclination 1 (H): 3 (V). ��� You can enter the stiffness of the pile cap. ��� The microlies lines are separated 0.556 m or 1.00 m in the same alignment. ��� The embedding of the micropiles in the tough substrate can be between 1.5 and 7.0 m. To "annul" the ground that is in front of the micro piles, along the slope, these elements clearly start working, efforts can be inferred shear stress and bending moment which may affect them (upper bound but pretty close to the real) solution. In this new modeling it has been considered both equivalent stiffness coefficient (��) as the treated soil crown concentric to the micropile. According to the latter, and by comparing these values with real modeling movements on field slopes instrumented with stability problems, it was verified that there is quite a significant similarity between the obtained theoretical values and the measured field in relation to the behavior of micropiles executed in embankments along the natural slope. Finally to complete the analysis of micropiles working in bending conditions, we have studied the case of micropiles arranged vertically, working as discontinued cut-off walls including anchors, applied to a real case in the city of Granada, in the play "Hospital of Our Lady of the Health ". CYPE numeric code, based on the reaction of the ground is simulated spring stiffness Kh or "subgrade" horizontal, introduced in modeling was used as variables for analysis: a) The different measurements obtained in field; b) The thickness of quaternary ground, so that could be determined, was variable, c) The stiffness and the prestress of the anchors. d) The stiffness of the ground through relative values of Kh, collected in the study of soils in Andalusia, particularly in the area of Granada. (previously study of the Andalusia soils) This cut-off wall was implemented with 4 inclinometers (introduced in armor tubes four micropiles) in order to control the horizontal displacements of the retaining wall during the relevant excavations, in order to ensure the safety of the whole. From the developed model calculation, it was found that the value of Kh becomes less important because a large number of anchors levels, with regard to the horizontal deformation of the cut-off wall. On the other hand, the bending moments are quite sensitive to the distance between anchors, the initial voltage value thereof and the value of Kh. This model has also been reproduced reliably displacement values measured in the field and deduce parameters terrain deformability, Kh, with values around half the measured Light Rail in Granada, but visibly higher than deductible of abacuses which can obtain Kh for granular soils with low cohesion (upper Quaternary gravels and Sevilla) such as Abacus Arozamena, because, in our view, to cementing materials in Granada. In short, previous deductions you might think on optimizing the design of micropiles in the works that are expected to perform in Granada, with similar characteristics to the case of the vertical cut-off wall braced through several levels of anchors and in which materials location have a geotechnical behavior similar to those studied, with the consequent economic savings. With all this, it is considered that a significant contribution have been made for the design of future works of micropiles, bending moment and shear stress working in slope stabilization works or excavations.

Evaluation of configurations of supply networks supported by it systems

Los sistemas transaccionales tales como los programas inform��ticos para la planificaci��n de recursos empresariales (ERP software) se han implementado ampliamente mientras que los sistemas anal��ticos para la gesti��n de la cadena de suministro (SCM software) no han tenido el ��xito deseado por la industria de tecnolog��a de informaci��n (TI). Aunque se documentan beneficios importantes derivados de las implantaciones de SCM software, las empresas industriales son reacias a invertir en este tipo de sistemas. Por una parte esto es debido a la falta de m��todos que son capaces de detectar los beneficios por emplear esos sistemas, y por otra parte porque el coste asociado no est�� identificado, detallado y cuantificado suficientemente. Los esquemas de coordinaci��n basados ��nicamente en sistemas ERP son alternativas v��lidas en la pr��ctica industrial siempre que la relaci��n coste-beneficio esta favorable. Por lo tanto, la evaluaci��n de formas organizativas teniendo en cuenta expl��citamente el coste debido a procesos administrativos, en particular por ciclos iterativos, es de gran inter��s para la toma de decisiones en el ��mbito de inversiones en TI. Con el fin de cerrar la brecha, el prop��sito de esta investigaci��n es proporcionar m��todos de evaluaci��n que permitan la comparaci��n de diferentes formas de organizaci��n y niveles de soporte por sistemas inform��ticos. La tesis proporciona una amplia introducci��n, analizando los retos a los que se enfrenta la industria. Concluye con las necesidades de la industria de SCM software: unas herramientas que facilitan la evaluaci��n integral de diferentes propuestas de organizaci��n. A continuaci��n, la terminolog��a clave se detalla centr��ndose en la teor��a de la organizaci��n, las peculiaridades de inversi��n en TI y la tipolog��a de software de gesti��n de la cadena de suministro. La revisi��n de la literatura clasifica las contribuciones recientes sobre la gesti��n de la cadena de suministro, tratando ambos conceptos, el dise��o de la organizaci��n y su soporte por las TI. La clasificaci��n incluye criterios relacionados con la metodolog��a de la investigaci��n y su contenido. Los estudios emp��ricos en el ��mbito de la administraci��n de empresas se centran en tipolog��as de redes industriales. Nuevos algoritmos de planificaci��n y esquemas de coordinaci��n innovadoras se desarrollan principalmente en el campo de la investigaci��n de operaciones con el fin de proponer nuevas funciones de software. Art��culos procedentes del ��rea de la gesti��n de la producci��n se centran en el an��lisis de coste y beneficio de las implantaciones de sistemas. La revisi��n de la literatura revela que el ��xito de las TI para la coordinaci��n de redes industriales depende en gran medida de caracter��sticas de tres dimensiones: la configuraci��n de la red industrial, los esquemas de coordinaci��n y las funcionalidades del software. La literatura disponible est�� enfocada sobre todo en los beneficios de las implantaciones de SCM software. Sin embargo, la coordinaci��n de la cadena de suministro, bas��ndose en el sistema ERP, sigue siendo la pr��ctica industrial generalizada, pero el coste de coordinaci��n asociado no ha sido abordado por los investigadores. Los fundamentos de dise��o organizativo eficiente se explican en detalle en la medida necesaria para la comprensi��n de la s��ntesis de las diferentes formas de organizaci��n. Se han generado varios esquemas de coordinaci��n variando los siguientes par��metros de dise��o: la estructura organizativa, los mecanismos de coordinaci��n y el soporte por TI. Las diferentes propuestas de organizaci��n desarrolladas son evaluadas por un m��todo heur��stico y otro basado en la simulaci��n por eventos discretos. Para ambos m��todos, se tienen en cuenta los principios de la teor��a de la organizaci��n. La falta de rendimiento empresarial se debe a las dependencias entre actividades que no se gestionan adecuadamente. Dentro del m��todo heur��stico, se clasifican las dependencias y se mide su intensidad bas��ndose en factores contextuales. A continuaci��n, se valora la idoneidad de cada elemento de dise��o organizativo para cada dependencia espec��fica. Por ��ltimo, cada forma de organizaci��n se eval��a bas��ndose en la contribuci��n de los elementos de dise��o tanto al beneficio como al coste. El beneficio de coordinaci��n se refiere a la mejora en el rendimiento log��stico - este concepto es el objeto central en la mayor��a de modelos de evaluaci��n de la gesti��n de la cadena de suministro. Por el contrario, el coste de coordinaci��n que se debe incurrir para lograr beneficios no se suele considerar en detalle. Procesos iterativos son costosos si se ejecutan manualmente. Este es el caso cuando SCM software no est�� implementada y el sistema ERP es el ��nico instrumento de coordinaci��n disponible. El modelo heur��stico proporciona un procedimiento simplificado para la clasificaci��n sistem��tica de las dependencias, la cuantificaci��n de los factores de influencia y la identificaci��n de configuraciones que indican el uso de formas organizativas y de soporte de TI m��s o menos complejas. La simulaci��n de eventos discretos se aplica en el segundo modelo de evaluaci��n utilizando el paquete de software ���Plant Simulation���. Con respecto al rendimiento log��stico, por un lado se mide el coste de fabricaci��n, de inventario y de transporte y las penalizaciones por p��rdida de ventas. Por otro lado, se cuantifica expl��citamente el coste de la coordinaci��n teniendo en cuenta los ciclos de coordinaci��n iterativos. El m��todo se aplica a una configuraci��n de cadena de suministro ejemplar considerando diversos par��metros. Los resultados de la simulaci��n confirman que, en la mayor��a de los casos, el beneficio aumenta cuando se intensifica la coordinaci��n. Sin embargo, en ciertas situaciones en las que se aplican ciclos de planificaci��n manuales e iterativos el coste de coordinaci��n adicional no siempre conduce a mejor rendimiento log��stico. Estos resultados inesperados no se pueden atribuir a ning��n par��metro particular. La investigaci��n confirma la gran importancia de nuevas dimensiones hasta ahora ignoradas en la evaluaci��n de propuestas organizativas y herramientas de TI. A trav��s del m��todo heur��stico se puede comparar de forma r��pida, pero s��lo aproximada, la eficiencia de diferentes formas de organizaci��n. Por el contrario, el m��todo de simulaci��n es m��s complejo pero da resultados m��s detallados, teniendo en cuenta par��metros espec��ficos del contexto del caso concreto y del dise��o organizativo. ABSTRACT Transactional systems such as Enterprise Resource Planning (ERP) systems have been implemented widely while analytical software like Supply Chain Management (SCM) add-ons are adopted less by manufacturing companies. Although significant benefits are reported stemming from SCM software implementations, companies are reluctant to invest in such systems. On the one hand this is due to the lack of methods that are able to detect benefits from the use of SCM software and on the other hand associated costs are not identified, detailed and quantified sufficiently. Coordination schemes based only on ERP systems are valid alternatives in industrial practice because significant investment in IT can be avoided. Therefore, the evaluation of these coordination procedures, in particular the cost due to iterations, is of high managerial interest and corresponding methods are comprehensive tools for strategic IT decision making. The purpose of this research is to provide evaluation methods that allow the comparison of different organizational forms and software support levels. The research begins with a comprehensive introduction dealing with the business environment that industrial networks are facing and concludes highlighting the challenges for the supply chain software industry. Afterwards, the central terminology is addressed, focusing on organization theory, IT investment peculiarities and supply chain management software typology. The literature review classifies recent supply chain management research referring to organizational design and its software support. The classification encompasses criteria related to research methodology and content. Empirical studies from management science focus on network types and organizational fit. Novel planning algorithms and innovative coordination schemes are developed mostly in the field of operations research in order to propose new software features. Operations and production management researchers realize cost-benefit analysis of IT software implementations. The literature review reveals that the success of software solutions for network coordination depends strongly on the fit of three dimensions: network configuration, coordination scheme and software functionality. Reviewed literature is mostly centered on the benefits of SCM software implementations. However, ERP system based supply chain coordination is still widespread industrial practice but the associated coordination cost has not been addressed by researchers. Fundamentals of efficient organizational design are explained in detail as far as required for the understanding of the synthesis of different organizational forms. Several coordination schemes have been shaped through the variation of the following design parameters: organizational structuring, coordination mechanisms and software support. The different organizational proposals are evaluated using a heuristic approach and a simulation-based method. For both cases, the principles of organization theory are respected. A lack of performance is due to dependencies between activities which are not managed properly. Therefore, within the heuristic method, dependencies are classified and their intensity is measured based on contextual factors. Afterwards the suitability of each organizational design element for the management of a specific dependency is determined. Finally, each organizational form is evaluated based on the contribution of the sum of design elements to coordination benefit and to coordination cost. Coordination benefit refers to improvement in logistic performance ��� this is the core concept of most supply chain evaluation models. Unfortunately, coordination cost which must be incurred to achieve benefits is usually not considered in detail. Iterative processes are costly when manually executed. This is the case when SCM software is not implemented and the ERP system is the only available coordination instrument. The heuristic model provides a simplified procedure for the classification of dependencies, quantification of influence factors and systematic search for adequate organizational forms and IT support. Discrete event simulation is applied in the second evaluation model using the software package ���Plant Simulation���. On the one hand logistic performance is measured by manufacturing, inventory and transportation cost and penalties for lost sales. On the other hand coordination cost is explicitly considered taking into account iterative coordination cycles. The method is applied to an exemplary supply chain configuration considering various parameter settings. The simulation results confirm that, in most cases, benefit increases when coordination is intensified. However, in some situations when manual, iterative planning cycles are applied, additional coordination cost does not always lead to improved logistic performance. These unexpected results cannot be attributed to any particular parameter. The research confirms the great importance of up to now disregarded dimensions when evaluating SCM concepts and IT tools. The heuristic method provides a quick, but only approximate comparison of coordination efficiency for different organizational forms. In contrast, the more complex simulation method delivers detailed results taking into consideration specific parameter settings of network context and organizational design.

Improving manufacturing performance by standardization of interprocess communication

A number of environmental forces such as increasing value chain network complexity, decreasing product life-cycle cost, and time-to-market requirements or increasing product complexity act upon manufacturing organizations, enhancing the acute need for organizational routines that foster efficient and effective communication between processes. Such organizational routines erode quickly in the absence of common standards for knowledge sharing, that is why successful manufacturing systems benefit from interprocess standardization. The purpose of this paper is to offer a standardization model of interprocess communication that increases manufacturing operational performance (MOP). First, we propose a novel holistic model that makes standardized interprocess communication possible in manufacturing organizations. Second, we propose a model for quantifying the implications of standardizing interprocess communication upon MOP. Finally, as a matter of application, we show the results of its successful implementation in one Japanese manufacturing organization.

Implementing fully homomorphic encryption schemes in FPGA-based systems

LLas nuevas tecnolog��as orientadas a la nube, el internet de las cosas o las tendencias "as a service" se basan en el almacenamiento y procesamiento de datos en servidores remotos. Para garantizar la seguridad en la comunicaci��n de dichos datos al servidor remoto, y en el manejo de los mismos en dicho servidor, se hace uso de diferentes esquemas criptogr��ficos. Tradicionalmente, dichos sistemas criptogr��ficos se centran en encriptar los datos mientras no sea necesario procesarlos (es decir, durante la comunicaci��n y almacenamiento de los mismos). Sin embargo, una vez es necesario procesar dichos datos encriptados (en el servidor remoto), es necesario desencriptarlos, momento en el cual un intruso en dicho servidor podr��a a acceder a datos sensibles de usuarios del mismo. Es m��s, este enfoque tradicional necesita que el servidor sea capaz de desencriptar dichos datos, teniendo que confiar en la integridad de dicho servidor de no comprometer los datos. Como posible soluci��n a estos problemas, surgen los esquemas de encriptaci��n homom��rficos completos. Un esquema homom��rfico completo no requiere desencriptar los datos para operar con ellos, sino que es capaz de realizar las operaciones sobre los datos encriptados, manteniendo un homomorfismo entre el mensaje cifrado y el mensaje plano. De esta manera, cualquier intruso en el sistema no podr��a robar m��s que textos cifrados, siendo imposible un robo de los datos sensibles sin un robo de las claves de cifrado. Sin embargo, los esquemas de encriptaci��n homom��rfica son, actualmente, dr��s-ticamente lentos comparados con otros esquemas de encriptaci��n cl��sicos. Una op��eraci��n en el anillo del texto plano puede conllevar numerosas operaciones en el anillo del texto encriptado. Por esta raz��n, est��n surgiendo distintos planteamientos sobre como acelerar estos esquemas para un uso pr��ctico. Una de las propuestas para acelerar los esquemas homom��rficos consiste en el uso de High-Performance Computing (HPC) usando FPGAs (Field Programmable Gate Arrays). Una FPGA es un dispositivo semiconductor que contiene bloques de l��gica cuya interconexi��n y funcionalidad puede ser reprogramada. Al compilar para FPGAs, se genera un circuito hardware espec��fico para el algorithmo proporcionado, en lugar de hacer uso de instrucciones en una m��quina universal, lo que supone una gran ventaja con respecto a CPUs. Las FPGAs tienen, por tanto, claras difrencias con respecto a CPUs: -Arquitectura en pipeline: permite la obtenci��n de outputs sucesivos en tiempo constante -Posibilidad de tener multiples pipes para computaci��n concurrente/paralela. As��, en este proyecto: -Se realizan diferentes implementaciones de esquemas homom��rficos en sistemas basados en FPGAs. -Se analizan y estudian las ventajas y desventajas de los esquemas criptogr��ficos en sistemas basados en FPGAs, comparando con proyectos relacionados. -Se comparan las implementaciones con trabajos relacionados New cloud-based technologies, the internet of things or "as a service" trends are based in data storage and processing in a remote server. In order to guarantee a secure communication and handling of data, cryptographic schemes are used. Tradi��tionally, these cryptographic schemes focus on guaranteeing the security of data while storing and transferring it, not while operating with it. Therefore, once the server has to operate with that encrypted data, it first decrypts it, exposing unencrypted data to intruders in the server. Moreover, the whole traditional scheme is based on the assumption the server is reliable, giving it enough credentials to decipher data to process it. As a possible solution for this issues, fully homomorphic encryption(FHE) schemes is introduced. A fully homomorphic scheme does not require data decryption to operate, but rather operates over the cyphertext ring, keeping an homomorphism between the cyphertext ring and the plaintext ring. As a result, an outsider could only obtain encrypted data, making it impossible to retrieve the actual sensitive data without its associated cypher keys. However, using homomorphic encryption(HE) schemes impacts performance dras-tically, slowing it down. One operation in the plaintext space can lead to several operations in the cyphertext space. Because of this, different approaches address the problem of speeding up these schemes in order to become practical. One of these approaches consists in the use of High-Performance Computing (HPC) using FPGAs (Field Programmable Gate Array). An FPGA is an integrated circuit designed to be configured by a customer or a designer after manufacturing - hence "field-programmable". Compiling into FPGA means generating a circuit (hardware) specific for that algorithm, instead of having an universal machine and generating a set of machine instructions. FPGAs have, thus, clear differences compared to CPUs: - Pipeline architecture, which allows obtaining successive outputs in constant time. -Possibility of having multiple pipes for concurrent/parallel computation. Thereby, In this project: -We present different implementations of FHE schemes in FPGA-based systems. -We analyse and study advantages and drawbacks of the implemented FHE schemes, compared to related work.

El an��lisis de la construcci��n sin p��rdidas (Lean Construction) y su relaci��n con el Project & Construction Management : propuesta de regulaci��n en Espa��a y su inclusi��n en la ley de la ordenaci��n de la edificaci��n

El presente trabajo se basa en la filosof��a de la Construcci��n sin P��rdidas (���Lean Construction���), analizando la situaci��n de esta filosof��a en el sector de la edificaci��n en el contexto internacional y espa��ol, respondiendo las siguientes preguntas: 1. ��C��mo surge el ���Lean Construction���? 2. ��Cu��les son sus actividades, funciones y cometidos? 3. ��Existe regulaci��n del ��Lean Construction��� en otros pa��ses? 4. ��Existe demanda del ��Lean Construction��� en Espa��a? 5. ��Existe regulaci��n del ��Lean Construction��� en Espa��a? 6. ��C��mo deber��a ser la regulaci��n ��Lean Construction��� en Espa��a? 7. ��Cu��l es la relaci��n del ���Lean Construction��� con el ���Project & Construction Management���? 8. ��C��mo deber��a ser la regulaci��n de ���Lean Construction��� en Espa��a considerando su relaci��n con el ���Project & Construction Management���? Las preguntas indicadas las hemos respondido detalladamente en el presente trabajo, a continuaci��n se resume las respuestas a dichas preguntas: 1. El ���Lean Construction��� surge en agosto de 1992, cuando el investigador finland��s Lauri Koskela public�� en la Universidad de Stanford el reporte TECHNICAL REPORT N�� 72 titulado ���Application of the New Production Philosophy to Construction���. Un a��o m��s tarde el Dr. Koskela invit�� a un grupo de especialistas en construcci��n al primer workshop de esta materia en Finlandia, dando origen al International Group for Lean Construction (IGLC) lo que ha permitido extender la filosof��a a EEUU, Europa, Am��rica, Asia, Ocean��a y ��frica. ���Lean Construction��� es un sistema basado en el enfoque ���Lean Production��� desarrollado en Jap��n por Toyota Motors a partir de los a��os cincuenta, sistema que permiti�� a sus f��bricas producir unidades con mayor eficiencia que las industrias americanas, con menores recursos, en menor tiempo, y con un n��mero menor de errores de fabricaci��n. 2. El sistema ���Lean Construction��� busca maximizar el valor y disminuir las p��rdidas de los proyectos generando una coordinaci��n eficiente entre los involucrados, manejando un proyecto como un sistema de producci��n, estrechando la colaboraci��n entre los participantes de los proyectos, capacit��ndoles y empoder��ndoles, fomentando una cultura de cambio. Su prop��sito es desarrollar un proceso de construcci��n en el que no hayan accidentes, ni da��os a equipos, instalaciones, entorno y comunidad, que se realice en conformidad con los requerimientos contractuales, sin defectos, en el plazo requerido, respetando los costes presupuestados y con un claro enfoque en la eliminaci��n o reducci��n de las p��rdidas, es decir, las actividades que no generen beneficios. El ���Last Planner System���, o ���Sistema del ��ltimo Planificador���, es un sistema del ���Lean Construction��� que por su propia naturaleza protege a la planificaci��n y, por ende, ayuda a maximizar el valor y minimizar las p��rdidas, optimizando de manera sustancial los sistemas de seguridad y salud. El ���Lean Construction��� se inici�� como un concepto enfocado a la ejecuci��n de las obras, posteriormente se aplic�� la filosof��a a todas las etapas del proyecto. Actualmente considera el desarrollo total de un proyecto, desde que nace la idea hasta la culminaci��n de la obra y puesta en marcha, considerando el ciclo de vida completo del proyecto. Es una filosof��a de gesti��n, metodolog��as de trabajo y una cultura empresarial orientada a la eficiencia de los procesos y flujos. La filosof��a ���Lean Construction��� se est�� expandiendo en todo el mundo, adem��s est�� creciendo en su alcance, influyendo en la gesti��n contractual de los proyectos. Su primera evoluci��n consisti�� en la creaci��n del sistema ���Lean Project Delivery System���, que es el concepto global de desarrollo de proyectos. Posteriormente, se proponen el ���Target Value Design���, que consiste en dise��ar de forma colaborativa para alcanzar los costes y el valor requerido, y el ���Integrated Project Delivery���, en relaci��n con sistemas de contratos relacionales (colaborativos) integrados, distintos a los contratos convencionales. 3. Se verific�� que no existe regulaci��n espec��fica del ��Lean Construction��� en otros pa��ses, en otras palabras, no existe el agente con el nombre espec��fico de ���Especialista en Lean Construction��� o similar, en consecuencia, es un agente adicional en el proyecto de la edificaci��n, cuyas funciones y cometidos se pueden solapar con los del ���Project Manager���, ���Construction Manager���, ���Contract Manager���, ���Safety Manager���, entre otros. Sin embargo, se comprob�� la existencia de formatos privados de contratos colaborativos de Integrated Project Delivery, los cuales podr��an ser tomados como unas primeras referencias para futuras regulaciones. 4. Se verific�� que s�� existe demanda del ��Lean Construction��� en el desarrollo del presente trabajo, aunque a��n su uso es incipiente, cada d��a existe m��s interesados en el tema. 5. No existe regulaci��n del ��Lean Construction��� en Espa��a. 6. Uno de los objetivos fundamentales de esta tesis es el de regular esta figura cuando act��e en un proyecto, definir y realizar una estructura de Agente de la Edificaci��n, seg��n la Ley de Ordenaci��n de la Edificaci��n (LOE), y de esta manera poder introducirla dentro de la Legislaci��n Espa��ola, protegi��ndola de eventuales responsabilidades civiles. En Espa��a existe jurisprudencia (sentencias de los tribunales de justicia espa��oles) con jurisdicci��n civil basada en la LOE para absolver o condenar a agentes de la edificaci��n que son definidos en los tribunales como ���gestores constructivos��� o similares. Por este motivo, en un futuro los tribunales podr��an dictaminar responsabilidades solidarias entre el especialista ���Lean Construction��� y otros agentes del proyecto, dependiendo de sus actuaciones, y seg��n se implemente el ���Lean Project Delivery System���, el ���Target Value Design��� y el ���Integrated Project Delivery���. Por otro lado, es posible que el nivel de actuaci��n del especialista ���Lean Construcci��n��� pueda abarcar la gesti��n del dise��o, la gesti��n de la ejecuci��n material (construcci��n), la gesti��n de contratos, o la gesti��n integral de todo el proyecto de edificaci��n, esto ��ltimo, en concordancia con la ��ltima Norma ISO 21500:2012 o UNE-ISO 21500:2013 Directrices para la direcci��n y gesti��n de proyectos. En consecuencia, se deber��a incorporar adecuadamente a uno o m��s agentes de la edificaci��n en la LOE de acuerdo a sus funciones y responsabilidades seg��n los niveles de actuaci��n del ���Especialista en Lean Construction���. Se propone la creaci��n de los siguientes agentes: Gestor del Dise��o, Gestor Constructivo y Gestor de Contratos, cuyas definiciones est��n desarrolladas en este trabajo. Estas figuras son definidas de manera general, puesto que cualquier ���Project Manager��� o ���DIPE���, gestor BIM (Building Information Modeling), o similar, puede actuar como uno o varios de ellos. Tambi��n se propone la creaci��n del agente ���Gestor de la Construcci��n sin P��rdidas���, como aquel agente que asume las actuaciones del ���gestor de dise��o���, ���gestor constructivo��� y ���gestor de contratos��� con un enfoque en los principios del Lean Production. 7. En la tesis se demuestra, por medio del uso de la ISO 21500, que ambos sistemas son complementarios, de manera que los proyectos pueden tener ambos enfoques y ser compatibilizados. Un proyecto que use el ���Project & Construction Management��� puede perfectamente apoyarse en las herramientas y t��cnicas del ���Lean Construction��� para asegurar la eliminaci��n o reducci��n de las p��rdidas, es decir, las actividades que no generen valor, dise��ando el sistema de producci��n, el sistema de dise��o o el sistema de contratos. 8. Se deber��a incorporar adecuadamente al agente de la edificaci��n ���Especialista en Lean Construction��� o similar y al agente ��Especialista en Project & Construction Management��� o DIPE en la Ley de Ordenaci��n de la Edificaci��n (LOE) de acuerdo a sus funciones y responsabilidades, puesto que la jurisprudencia se ha basado para absolver o condenar en la referida Ley. Uno de los objetivos fundamentales de esta tesis es el de regular la figura del ���Especialista en Lean Construction��� cuando act��a simult��neamente con el DIPE, y realizar una estructura de Agente de la Edificaci��n seg��n la LOE, y de esta manera protegerlo de eventuales responsabilidades solidarias. Esta investigaci��n comprueba que la propuesta de definici��n del agente de edificaci��n DIPE, seg��n la LOE, presentada en la tesis doctoral del Doctor Manuel Soler Severino es compatible con las nuevas definiciones propuestas. El agente DIPE puede asumir los roles de los diferentes gestores propuestos en esta tesis si es que se especializa en dichas materias, o, si lo estima pertinente, recomendar sus contrataciones. ABSTRACT This work is based on the Lean Construction philosophy; an analysis is made herein with regard to the situation of this philosophy in the building sector within the international and Spanish context, replying to the following questions: 1. How did the concept of Lean Construction emerge? 2. Which are the activities, functions and objectives of Lean Construction? 3. Are there regulations on Lean Construction in other countries? 4. Is there a demand for Lean Construction in Spain? 5. Are there regulations on Lean Construction in Spain? 6. How should regulations on Lean Construction be developed in Spain? 7. What is the relationship between Lean Construction and the Project & Construction Management? 8. How should regulations on Lean Construction be developed in Spain considering its relationship with the Project & Construction Management? We have answered these questions in detail here and the replies are summarized as follows: 1. The concept of Lean Construction emerged in august of 1992, when Finnish researcher Lauri Koskela published in Stanford University TECHNICAL REPORT N�� 72 entitled ���Application of the New Production Philosophy to Construction���. A year later, Professor Koskela invited a group of construction specialists to Finland to the first workshop conducted on this matter; thus, the International Group for Lean Construction (IGLC) was established, which has contributed to extending the philosophy to the United States, Europe, the Americas, Asia, Oceania, and Africa. Lean Construction is a system based on the Lean Production approach, which was developed in Japan by Toyota Motors in the 1950s. Thanks to this system, the Toyota plants were able to produce more units, with greater efficiency than the American industry, less resources, in less time, and with fewer manufacturing errors. 2. The Lean Construction system aims at maximizing the value of projects while reducing waste, producing an effective coordination among those involved; it manages projects as a production system, enhancing collaboration between the parties that participate in the projects while building their capacities, empowering them, and promoting a culture of change. Its purpose is to develop a construction process free of accidents, without damages to the equipment, facilities, environment and community, flawless, in accordance with contractual requirements, within the terms established, respecting budgeted costs, and with a clear approach to eliminating or reducing waste, that is, activities that do not generate benefits. The Last Planner System is a Lean Construction system, which by its own nature protects planning and, therefore, helps to maximize the value and minimize waste, optimizing substantially the safety and health systems. Lean Construction started as a concept focused on the execution of works, and subsequently the philosophy was applied to all the stages of the project. At present it considers the project���s total development, since the time ideas are born until the completion and start-up of the work, taking into account the entire life cycle of the project. It is a philosophy of management, work methodologies, and entrepreneurial culture aimed at the effectiveness of processes and flows. The Lean Construction philosophy is extending all over the world and its scope is becoming broader, having greater influence on the contractual management of projects. It evolved initially through the creation of the Lean Project Delivery System, a global project development concept. Later on, the Target Value Design was developed, based on collaborative design to achieve the costs and value required, as well as the Integrated Project Delivery, in connection with integrated relational (collaborative) contract systems, as opposed to conventional contracts. 3. It was verified that no specific regulations on Lean Construction exist in other countries, in other words, there are no agents with the specific name of ���Lean Construction Specialist��� or other similar names; therefore, it is an additional agent in building projects, which functions and objectives can overlap those of the Project Manager, Construction Manager, Contract Manager, or Safety Manager, among others. However, the existence of private collaborative contracts of Integrated Project Delivery was confirmed, which could be considered as first references for future regulations. 4. There is a demand for Lean Construction in the development of this work; even though it is still emerging, there is a growing interest in this topic. 5. There are no regulations on Lean Construction in Spain. 6. One of the main objectives of this thesis is to regulate this role when acting in a project, and to define and develop a Building Agent structure, according to the Building Standards Law (LOE by its acronym in Spanish), in order to be able to incorporate it into the Spanish law, protecting it from civil liabilities. In Spain there is jurisprudence in civil jurisdiction based on the LOE to acquit or convict building agents, which are defined in the courts as ���construction managers��� or similar. For this reason, courts could establish in the future joint and several liabilities between the Lean Construction Specialist and other agents of the project, depending on their actions and based on the implementation of the Lean Project Delivery System, the Target Value Design, and the Integrated Project Delivery. On the other hand, it is possible that the level of action of the Lean Construction Specialist may comprise design management, construction management and contract management, or the integral management of the entire building project in accordance with the last ISO 21500:2012 or UNE-ISO 21500:2013, guidelines for the management of projects. Accordingly, one or more building agents should be appropriately incorporated into the LOE according to their functions and responsibilities and based on the levels of action of the Lean Construction Specialist. The creation of the following agents is proposed: Design Manager, Construction Manager, and Contract Manager, which definitions are developed in this work. These agents are defined in general, since any Project Manager or DIPE, Building Information Modeling (BIM) Manager or similar, may act as one or as many of them. The creation of the Lean Construction Manager is also proposed, as the agent that takes on the role of the Design Manager, Construction Manager and Contract Manager with a focus on the Lean Production principles. 7. In the thesis it is demonstrated that through the implementation of the ISO 21500, both systems are supplementary, so projects may have both approaches and be compatible. A project that applies the Project & Construction Management may perfectly have the support of the tools, techniques and practices of Lean Construction to ensure the elimination or reduction of losses, that is, those activities that do not generate value, thus designing the production system, the design system, or the contract system. 8. The Lean Construction Specialist or similar and the Specialist in Project & Construction Management should be incorporated appropriately into the LOE according to their functions and responsibilities, since jurisprudence has been based on such Law to acquit or convict. One of the main objectives of this thesis is the regulate the role of the Lean Construction Specialist when acting simultaneously with the DIPE, and to develop a structure of the building agent, according to the LOE, and in this way protect such agent from joint and several liabilities. This research proves that the proposal to define the DIPE building agent, according to the LOE, and presented in the doctoral dissertation of Manuel Soler Severino, Ph.D. is compatible with the new definitions proposed. The DIPE agent may assume the roles of the different managers proposed in this thesis if he specializes in those topics or, if deemed pertinent, recommends that they be engaged.

Aprendizaje integrado en arquitectura con modelos virtuales : implementaci��n de metodolog��a BIM en la docencia universitaria

Los procesos de dise��o y construcci��n en Arquitectura han mostrado un desarrollo de optimizaci��n hist��ricamente muy deficiente cuando se compara con las restantes actividades t��picamente industriales. La aspiraci��n constante a una industrializaci��n efectiva, tanto en aras de alcanzar mayores cotas de calidad as�� como de ahorro de recursos, recibe hoy una oportunidad inmejorable desde el ��mbito inform��tico: el Building Information Modelling o BIM. Lo que en un inicio puede parecer meramente un determinado tipo de programa inform��tico, en realidad supone un concepto de ���proceso��� que subvierte muchas rutinas hoy habituales en el desarrollo de proyectos y construcciones arquitect��nicas. La inclusi��n y desarrollo de datos ligados al proyecto, desde su inicio hasta el fin de su ciclo de vida, conlleva la oportunidad de crear una realidad virtual din��mica y actualizable, que por a��adidura posibilita su ensayo y optimizaci��n en todos sus aspectos: antes y durante su ejecuci��n, as�� como vida ��til. A ello se suma la oportunidad de transmitir eficientemente los datos completos de proyecto, sin apenas p��rdidas o reelaboraci��n, a la cadena de fabricaci��n, lo que facilita el paso a una industrializaci��n verdaderamente significativa en edificaci��n. Ante una llamada mundial a la optimizaci��n de recursos y el inter��s indudable de aumentar beneficios econ��micos por medio de la reducci��n del factor de incertidumbre de los procesos, BIM supone un opci��n de mejora indudable, y as�� ha sido reconocido a trav��s de la inminente implantaci��n obligatoria por parte de los gobiernos (p. ej. Gran Breta��a en 2016 y Espa��a en 2018). La modificaci��n de procesos y roles profesionales que conlleva la incorporaci��n de BIM resulta muy significativa y marcar�� el ejercicio profesional de los futuros graduados en las disciplinas de Arquitectura, Ingenier��a y Construcci��n (AEC por sus siglas en ingl��s). La universidad debe responder ��gilmente a estas nuevas necesidades incorporando esta metodolog��a en la ense��anza reglada y aportando una visi��n sin��rgica que permita extraer los beneficios formativos subyacentes en el propio marco BIM. En este sentido BIM, al aglutinar el conjunto de datos sobre un ��nico modelo virtual, ofrece un potencial singularmente interesante. La realidad tridimensional del modelo, desarrollada y actualizada continuamente, ofrece al estudiante una gesti��n radicalmente distinta de la representaci��n gr��fica, en la que las vistas parciales de secciones y plantas, tan complejas de asimilar en los inicios de la formaci��n universitaria, resultan en una mera petici��n a posteriori, para ser extra��da seg��n necesidad del modelo virtual. El dise��o se realiza siempre sobre el propio modelo ��nico, independientemente de la vista de trabajo elegida en cada momento, permaneciendo los datos y sus relaciones constructivas siempre actualizados y plenamente coherentes. Esta descripci��n condensada de caracter��sticas de BIM preconfiguran gran parte de las beneficios formativos que ofrecen los procesos BIM, en especial, en referencia al desarrollo del dise��o integrado y la gesti��n de la informaci��n (incluyendo TIC). Destacan a su vez las facilidades en comprensi��n visual de elementos arquitect��nicos, sistemas t��cnicos, sus relaciones intr��nsecas as�� como procesos constructivos. A ello se une el desarrollo experimental que la plataforma BIM ofrece a trav��s de sus software colaborativos: la simulaci��n del comportamiento estructural, energ��tico, econ��mico, entre otros muchos, del modelo virtual en base a los datos inherentes del proyecto. En la presente tesis se describe un estudio de conjunto para explicitar tanto las cualidades como posibles reservas en el uso de procesos BIM, en el marco de una disciplina concreta: la docencia de la Arquitectura. Para ello se ha realizado una revisi��n bibliogr��fica general sobre BIM y espec��fica sobre docencia en Arquitectura, as�� como analizado las experiencias de distintos grupos de inter��s en el marco concreto de la ense��anza de la en Arquitectura en la Universidad Europea de Madrid. El an��lisis de beneficios o reservas respecto al uso de BIM se ha enfocado a trav��s de la encuesta a estudiantes y la entrevista a profesionales AEC relacionados o no con BIM. Las conclusiones del estudio permiten sintetizar una implantaci��n de metodolog��a BIM que para mayor claridad y facilidad de comunicaci��n y manejo, se ha volcado en un Marco de Implantaci��n eminentemente gr��fico. En ��l se orienta sobre las acciones docentes para el desarrollo de competencias concretas, vali��ndose de la flexibilidad conceptual de los Planes de Estudio en el contexto del Espacio Europeo de Educaci��n Superior (Declaraci��n de Bolonia) para incorporar con naturalidad la nueva herramienta docente al servicio de los objetivos formativo legalmente establecidos. El enfoque global del Marco de Implementaci��n propuesto facilita la planificaci��n de acciones formativas con perspectiva de conjunto: combinar los formatos puntuales o vehiculares BIM, establecer sinergias transversales y armonizar recursos, de modo que la metodolog��a pueda beneficiar tanto la asimilaci��n de conocimientos y habilidades establecidas para el t��tulo, como el propio flujo de aprendizaje o learn flow BIM. Del mismo modo reserva, incluso visualmente, aquellas ��reas de conocimiento en las que, al menos en la planificaci��n actual, la inclusi��n de procesos BIM no se considera ventajosa respecto a otras metodolog��as, o incluso inadecuadas para los objetivos docentes establecidos. Y es esta ��ltima categorizaci��n la que caracteriza el conjunto de conclusiones de esta investigaci��n, centrada en: 1. la incuestionable necesidad de formar en conceptos y procesos BIM desde etapas muy iniciales de la formaci��n universitaria en Arquitectura, 2. los beneficios formativos adicionales que aporta BIM en el desarrollo de competencias muy diversas contempladas en el curr��culum acad��mico y 3. la especificidad del rol profesional del arquitecto que exigir�� una implantaci��n cuidadosa y ponderada de BIM que respete las metodolog��as de desarrollo creativo tradicionalmente efectivas, y aporte valor en una reorientaci��n simbi��tica con el dise��o param��trico y fabricaci��n digital que permita un dise��o finalmente generativo. ABSTRACT The traditional architectural design and construction procedures have proven to be deficient where process optimization is concerned, particularly when compared to other common industrial activities. The ever���growing strife to achieve effective industrialization, both in favor of reaching greater quality levels as well as sustainable management of resources, has a better chance today than ever through a mean out of the realm of information technology, the Building Information Modelling o BIM. What may initially seem to be merely another computer program, in reality turns out to be a ���process��� concept that subverts many of today���s routines in architectural design and construction. Including and working with project data from the very beginning to the end of its full life cycle allows for creating a dynamic and updatable virtual reality, enabling data testing and optimizing throughout: before and during execution, all the way to the end of its lifespan. In addition, there is an opportunity to transmit complete project data efficiently, with hardly any loss or redeveloping of the manufacture chain required, which facilitates attaining a truly significant industrialization within the construction industry. In the presence of a world���wide call for optimizing resources, along with an undeniable interest in increasing economic benefits through reducing uncertainty factors in its processes, BIM undoubtedly offers a chance for improvement as acknowledged by its imminent and mandatory implementation on the part of governments (for example United Kingdom in 2016 and Spain in 2018). The changes involved in professional roles and procedures upon incorporating BIM are highly significant and will set the course for future graduates of Architecture, Engineering and Construction disciplines (AEC) within their professions. Higher Education must respond to such needs with swiftness by incorporating this methodology into their educational standards and providing a synergetic vision that focuses on the underlying educational benefits inherent in the BIM framework. In this respect, BIM, in gathering data set under one single virtual model, offers a uniquely interesting potential. The three���dimensional reality of the model, under continuous development and updating, provides students with a radically different graphic environment, in which partial views of elevation, section or plan that tend characteristically to be difficult to assimilate at the beginning of their studies, become mere post hoc requests to be ordered when needed directly out the virtual model. The design is always carried out on the sole model itself, independently of the working view chosen at any particular moment, with all data and data relations within construction permanently updated and fully coherent. This condensed description of the features of BIM begin to shape an important part of the educational benefits posed by BIM processes, particularly in reference to integrated design development and information management (including ITC). At the same time, it highlights the ease with which visual understanding is achieved regarding architectural elements, technology systems, their intrinsic relationships, and construction processes. In addition to this, there is the experimental development the BIM platform grants through its collaborative software: simulation of structural, energetic, and economic behavior, among others, of the virtual model according to the data inherent to the project. This doctoral dissertation presents a broad study including a wide array of research methods and issues in order to specify both the virtues and possible reservations in the use of BIM processes within the framework of a specific discipline: teaching Architecture. To do so, a literature review on BIM has been carried out, specifically concerning teaching in the discipline of Architecture, as well as an analysis of the experience of different groups of interest delimited to Universidad Europea de Madrid. The analysis of the benefits and/or limitations of using BIM has been approached through student surveys and interviews with professionals from the AEC sector, associated or not, with BIM. Various diverse educational experiences are described and academic management for experimental implementation has been analyzed. The conclusions of this study offer a synthesis for a Framework of Implementation of BIM methodology, which in order to reach greater clarity, communication ease and user���friendliness, have been posed in an eminently graphic manner. The proposed framework proffers guidance on teaching methods conducive to the development of specific skills, taking advantage of the conceptual flexibility of the European Higher Education Area guidelines based on competencies, which naturally facilitate for the incorporation of this new teaching tool to achieve the educational objectives established by law. The global approach of the Implementation Framework put forth in this study facilitates the planning of educational actions within a common perspective: combining exceptional or vehicular BIM formats, establishing cross���disciplinary synergies, and sharing resources, so as to purport a methodology that contributes to the assimilation of knowledge and pre���defined competencies within the degree program, and to the flow of learning itself. At the same time, it reserves, even visually, those areas of knowledge in which the use of BIM processes is not considered necessarily an advantage over other methodologies, or even inadequate for the learning outcomes established, at least where current planning is concerned. It is this last category which characterizes the research conclusions as a whole, centering on: 1. The unquestionable need for teaching BIM concepts and processes in Architecture very early on, in the initial stages of higher education; 2. The additional educational benefits that BIM offers in a varied array of competency development within the academic curriculum; and 3. The specific nature of the professional role of the Architect, which demands a careful and balanced implementation of BIM that respects the traditional teaching methodologies that have proven effective and creative, and adds value by a symbiotic reorientation merged with parametric design and digital manufacturing so to enable for a finally generative design.

Automated wordlength optimization framework for multi-source statistical interval-based analysis of nonlinear systems with control-flow structures

El uso de aritm��tica de punto fijo es una opci��n de dise��o muy extendida en sistemas con fuertes restricciones de ��rea, consumo o rendimiento. Para producir implementaciones donde los costes se minimicen sin impactar negativamente en la precisi��n de los resultados debemos llevar a cabo una asignaci��n cuidadosa de anchuras de palabra. Encontrar la combinaci��n ��ptima de anchuras de palabra en coma fija para un sistema dado es un problema combinatorio NP-hard al que los dise��adores dedican entre el 25 y el 50 % del ciclo de dise��o. Las plataformas hardware reconfigurables, como son las FPGAs, tambi��n se benefician de las ventajas que ofrece la aritm��tica de coma fija, ya que ��stas compensan las frecuencias de reloj m��s bajas y el uso m��s ineficiente del hardware que hacen estas plataformas respecto a los ASICs. A medida que las FPGAs se popularizan para su uso en computaci��n cient��fica los dise��os aumentan de tama��o y complejidad hasta llegar al punto en que no pueden ser manejados eficientemente por las t��cnicas actuales de modelado de se��al y ruido de cuantificaci��n y de optimizaci��n de anchura de palabra. En esta Tesis Doctoral exploramos distintos aspectos del problema de la cuantificaci��n y presentamos nuevas metodolog��as para cada uno de ellos: Las t��cnicas basadas en extensiones de intervalos han permitido obtener modelos de propagaci��n de se��al y ruido de cuantificaci��n muy precisos en sistemas con operaciones no lineales. Nosotros llevamos esta aproximaci��n un paso m��s all�� introduciendo elementos de Multi-Element Generalized Polynomial Chaos (ME-gPC) y combin��ndolos con una t��cnica moderna basada en Modified Affine Arithmetic (MAA) estad��stico para as�� modelar sistemas que contienen estructuras de control de flujo. Nuestra metodolog��a genera los distintos caminos de ejecuci��n autom��ticamente, determina las regiones del dominio de entrada que ejercitar��n cada uno de ellos y extrae los momentos estad��sticos del sistema a partir de dichas soluciones parciales. Utilizamos esta t��cnica para estimar tanto el rango din��mico como el ruido de redondeo en sistemas con las ya mencionadas estructuras de control de flujo y mostramos la precisi��n de nuestra aproximaci��n, que en determinados casos de uso con operadores no lineales llega a tener tan solo una desviaci��n del 0.04% con respecto a los valores de referencia obtenidos mediante simulaci��n. Un inconveniente conocido de las t��cnicas basadas en extensiones de intervalos es la explosi��n combinacional de t��rminos a medida que el tama��o de los sistemas a estudiar crece, lo cual conlleva problemas de escalabilidad. Para afrontar este problema presen tamos una t��cnica de inyecci��n de ruidos agrupados que hace grupos con las se��ales del sistema, introduce las fuentes de ruido para cada uno de los grupos por separado y finalmente combina los resultados de cada uno de ellos. De esta forma, el n��mero de fuentes de ruido queda controlado en cada momento y, debido a ello, la explosi��n combinatoria se minimiza. Tambi��n presentamos un algoritmo de particionado multi-v��a destinado a minimizar la desviaci��n de los resultados a causa de la p��rdida de correlaci��n entre t��rminos de ruido con el objetivo de mantener los resultados tan precisos como sea posible. La presente Tesis Doctoral tambi��n aborda el desarrollo de metodolog��as de optimizaci��n de anchura de palabra basadas en simulaciones de Monte-Cario que se ejecuten en tiempos razonables. Para ello presentamos dos nuevas t��cnicas que exploran la reducci��n del tiempo de ejecuci��n desde distintos ��ngulos: En primer lugar, el m��todo interpolativo aplica un interpolador sencillo pero preciso para estimar la sensibilidad de cada se��al, y que es usado despu��s durante la etapa de optimizaci��n. En segundo lugar, el m��todo incremental gira en torno al hecho de que, aunque es estrictamente necesario mantener un intervalo de confianza dado para los resultados finales de nuestra b��squeda, podemos emplear niveles de confianza m��s relajados, lo cual deriva en un menor n��mero de pruebas por simulaci��n, en las etapas iniciales de la b��squeda, cuando todav��a estamos lejos de las soluciones optimizadas. Mediante estas dos aproximaciones demostramos que podemos acelerar el tiempo de ejecuci��n de los algoritmos cl��sicos de b��squeda voraz en factores de hasta x240 para problemas de tama��o peque��o/mediano. Finalmente, este libro presenta HOPLITE, una infraestructura de cuantificaci��n automatizada, flexible y modular que incluye la implementaci��n de las t��cnicas anteriores y se proporciona de forma p��blica. Su objetivo es ofrecer a desabolladores e investigadores un entorno com��n para prototipar y verificar nuevas metodolog��as de cuantificaci��n de forma sencilla. Describimos el flujo de trabajo, justificamos las decisiones de dise��o tomadas, explicamos su API p��blica y hacemos una demostraci��n paso a paso de su funcionamiento. Adem��s mostramos, a trav��s de un ejemplo sencillo, la forma en que conectar nuevas extensiones a la herramienta con las interfaces ya existentes para poder as�� expandir y mejorar las capacidades de HOPLITE. ABSTRACT Using fixed-point arithmetic is one of the most common design choices for systems where area, power or throughput are heavily constrained. In order to produce implementations where the cost is minimized without negatively impacting the accuracy of the results, a careful assignment of word-lengths is required. The problem of finding the optimal combination of fixed-point word-lengths for a given system is a combinatorial NP-hard problem to which developers devote between 25 and 50% of the design-cycle time. Reconfigurable hardware platforms such as FPGAs also benefit of the advantages of fixed-point arithmetic, as it compensates for the slower clock frequencies and less efficient area utilization of the hardware platform with respect to ASICs. As FPGAs become commonly used for scientific computation, designs constantly grow larger and more complex, up to the point where they cannot be handled efficiently by current signal and quantization noise modelling and word-length optimization methodologies. In this Ph.D. Thesis we explore different aspects of the quantization problem and we present new methodologies for each of them: The techniques based on extensions of intervals have allowed to obtain accurate models of the signal and quantization noise propagation in systems with non-linear operations. We take this approach a step further by introducing elements of MultiElement Generalized Polynomial Chaos (ME-gPC) and combining them with an stateof- the-art Statistical Modified Affine Arithmetic (MAA) based methodology in order to model systems that contain control-flow structures. Our methodology produces the different execution paths automatically, determines the regions of the input domain that will exercise them, and extracts the system statistical moments from the partial results. We use this technique to estimate both the dynamic range and the round-off noise in systems with the aforementioned control-flow structures. We show the good accuracy of our approach, which in some case studies with non-linear operators shows a 0.04 % deviation respect to the simulation-based reference values. A known drawback of the techniques based on extensions of intervals is the combinatorial explosion of terms as the size of the targeted systems grows, which leads to scalability problems. To address this issue we present a clustered noise injection technique that groups the signals in the system, introduces the noise terms in each group independently and then combines the results at the end. In this way, the number of noise sources in the system at a given time is controlled and, because of this, the combinato rial explosion is minimized. We also present a multi-way partitioning algorithm aimed at minimizing the deviation of the results due to the loss of correlation between noise terms, in order to keep the results as accurate as possible. This Ph.D. Thesis also covers the development of methodologies for word-length optimization based on Monte-Carlo simulations in reasonable times. We do so by presenting two novel techniques that explore the reduction of the execution times approaching the problem in two different ways: First, the interpolative method applies a simple but precise interpolator to estimate the sensitivity of each signal, which is later used to guide the optimization effort. Second, the incremental method revolves on the fact that, although we strictly need to guarantee a certain confidence level in the simulations for the final results of the optimization process, we can do it with more relaxed levels, which in turn implies using a considerably smaller amount of samples, in the initial stages of the process, when we are still far from the optimized solution. Through these two approaches we demonstrate that the execution time of classical greedy techniques can be accelerated by factors of up to ��240 for small/medium sized problems. Finally, this book introduces HOPLITE, an automated, flexible and modular framework for quantization that includes the implementation of the previous techniques and is provided for public access. The aim is to offer a common ground for developers and researches for prototyping and verifying new techniques for system modelling and word-length optimization easily. We describe its work flow, justifying the taken design decisions, explain its public API and we do a step-by-step demonstration of its execution. We also show, through an example, the way new extensions to the flow should be connected to the existing interfaces in order to expand and improve the capabilities of HOPLITE.

Understanding structural divergence in European manufacturing

The heterogeneity among European manufacturing systems has widened in the last fifteen years under the competitive pressure of new industrial powers within and outside the EU boundaries, and as a result of the 2008 global recession. This paper describes such transformation, in terms of the sectoral composition and the geographical concentration of industrial activities. It also analyzes how cross-country differences in the export performance, in the levels of domestic demand and in the exposure to low-cost import competition have contributed to the divergence in European manufacturing.

Implementing an Integrated Management System (IMS) at an Aerospace Manufacturing Facility

This project analyzes the challenges, issues, benefits, and lessons learned that several companies experienced while implementing integrated management systems. Based on previous experiences, this paper defines several strategies that an organization should use to increase the probability of implementing an integrated management system (IMS) successfully. Strategies include completing a feasibility analysis, creating a policy, allocating resources, developing objectives, modifying documentation, and creating a continuous monitoring process. Moreover, an organization can reduce potential obstacles by promoting a culture that encourages management commitment and employee participation. Results indicate the implementation of an IMS provides the framework to manage environmental, health, and safety programs effectively. By implementing an IMS, an organization can save time and money, as well as proactively control risk.

A new paradigm: cloud agile manufacturing

Cloud Agile Manufacturing is a new paradigm proposed in this article. The main objective of Cloud Agile Manufacturing is to offer industrial production systems as a service. Thus users can access any functionality available in the cloud of manufacturing (process design, production, management, business integration, factories virtualization, etc.) without knowledge ��� or at least without having to be experts ��� in managing the required resources. The proposal takes advantage of many of the benefits that can offer technologies and models like: Business Process Management (BPM), Cloud Computing, Service Oriented Architectures (SOA) and Ontologies. To develop the proposal has been taken as a starting point the Semantic Industrial Machinery as a Service (SIMaaS) proposed in previous work. This proposal facilitates the effective integration of industrial machinery in a computing environment, offering it as a network service. The work also includes an analysis of the benefits and disadvantages of the proposal.

Cloud agile manufacturing

This paper proposes a new manufacturing paradigm, we call Cloud Agile Manufacturing, and whose principal objective is to offer industrial production systems as a service. Thus users can access any functionality available in the cloud of manufacturing (process design, production, management, business integration, factories virtualization, etc.) without knowledge ��� or at least without having to be experts ��� in managing the required resources. The proposal takes advantage of many of the benefits that can offer technologies and models like: Business Process Management (BPM), Cloud Computing, Service Oriented Architectures (SOA) and Ontologies. To develop the proposal has been taken as a starting point the Semantic Industrial Machinery as a Service (SIMaaS) proposed in previous work. This proposal facilitates the effective integration of industrial machinery in a computing environment, offering it as a network service. The work also includes an analysis of the benefits and disadvantages of the proposal.

An application of fuzzy logic for hardware/software partitioning in embedded systems

Hardware/Software partitioning (HSP) is a key task for embedded system co-design. The main goal of this task is to decide which components of an application are to be executed in a general purpose processor (software) and which ones, on a specific hardware, taking into account a set of restrictions expressed by metrics. In last years, several approaches have been proposed for solving the HSP problem, directed by metaheuristic algorithms. However, due to diversity of models and metrics used, the choice of the best suited algorithm is an open problem yet. This article presents the results of applying a fuzzy approach to the HSP problem. This approach is more flexible than many others due to the fact that it is possible to accept quite good solutions or to reject other ones which do not seem good. In this work we compare six metaheuristic algorithms: Random Search, Tabu Search, Simulated Annealing, Hill Climbing, Genetic Algorithm and Evolutionary Strategy. The presented model is aimed to simultaneously minimize the hardware area and the execution time. The obtained results show that Restart Hill Climbing is the best performing algorithm in most cases.

A parallel method for impulsive image noise removal on hybrid CPU/GPU systems

A parallel algorithm for image noise removal is proposed. The algorithm is based on peer group concept and uses a fuzzy metric. An optimization study on the use of the CUDA platform to remove impulsive noise using this algorithm is presented. Moreover, an implementation of the algorithm on multi-core platforms using OpenMP is presented. Performance is evaluated in terms of execution time and a comparison of the implementation parallelised in multi-core, GPUs and the combination of both is conducted. A performance analysis with large images is conducted in order to identify the amount of pixels to allocate in the CPU and GPU. The observed time shows that both devices must have work to do, leaving the most to the GPU. Results show that parallel implementations of denoising filters on GPUs and multi-cores are very advisable, and they open the door to use such algorithms for real-time processing.