On the allowance for support costs in Prager-Rozvany’ optimal layout theory

A recent study by Rozvany and Sokól discussed an important topic in structural design: the allowance for support costs in the optimization process. This paper examines a frequently used kind of support —that of simple foundation with horizontal reaction by friction— that appears no covered for the Authors’ approach. A simple example is examined to illustrate the case and to apply the Authors’ method and the standard design method.

Xyloglucan endotransglucosylase and cell wall extensibility

Transgenic tomato hypocotyls with altered levels of an XTH gene were used to study how XET activity could affect the hypocotyl growth and cell wall extensibility. Transgenic hypocotyls showed significant over-expression (line 13) or co-suppression (line 33) of the SlXTH1 in comparison with the wild type, with these results being correlated with the results on specific soluble XET activity, suggesting that SlXTH1 translates mainly for a soluble XET isoenzyme. A relationship between XET activity and cell wall extensibility was found, and the highest total extensibility was located in the apical hypocotyl segment of the over-expressing SlXTH1 line, where the XET-specific activity and hypocotyl growth were also highest compared with the wild line.

On the layout of a least weight single span structure with uniform load. Some comments and improvements

Beghini et al (Struct Multidisc Optim doi:10.1007/s00158-013-1030-6, 2013) have published a very interesting paper arriving to practically the same nearly optimal solutions for the so named “bridge prob- lem” that the Writers published a year before, but using an alternative and remarkable approach to the problem. In spite of this general agreement, the Writers think that some details of the paper can be improved and there are results that can be given a clear and mean- ingful interpretation thanks to an old and practically unknown theorem on optimal slenderness.

Tools for mixed-criticality partitioned systems: partitioning algorithm and extensibility support

The development of mixed-criticality virtualized multicore systems poses new challenges that are being subject of active research work. There is an additional complexity: it is now required to identify a set of partitions, and allocate applications to partitions. In this job, a number of issues have to be considered, such as the criticality level of the application, security and dependability requirements, operating system used by the application, time requirements granularity, specific hardware needs, etc. MultiPARTES [6] toolset relies on Model Driven Engineering (MDE) [12], which is a suitable approach in this setting. In this paper, it is described the support provided for automatic system partitioning generation and toolset extensibility.

Similarities and Differences in Barrel Vaults of Traditional and Stately Houses in the Historic Centre of Arequipa, Perú

The traditional architecture of the centre of the city of Arequipa has been analyzed by comparing floor-plans of houses from the eighteenth and nineteenth centuries in order to explain the reasons behind the arrangement of their constructional elements and the evolution of said elements and floor-plans. The historic centre of Arequipa, a city located in the South of Perú, South America (Latitude 16°23' South, Longitude 71 °31' West), is based on a ground plan from 1540 that was set during the city's Spanish foundation. It was declared Patrimony of the Humanity by UNESCO. The manorial architecture is widely known for its decorated fronts and one-of-a-kind designs, but its differences with respect to the popular architecture are not based exclusively on decorative aspects. Peru's colonial period finished around 1825, but the barrel-vault, construction style continued in Arequipa through 1868, when an earthquake destroyed the city. Thereafter, the vaults were replaced by roofs made of rails, with cinders made out of the lava stone. The stately houses belonged to the founding families who settled around the main square on forty nine blocks that formed a square-grid, street layout. Also belonging to this category are the houses of landlords and traders from post-colonial times.

Using the Journalistic Metaphor to Design User Interfaces That Explain Sensor Data

Facilitating general access to data from sensor networks (including traffic, hydrology and other domains) increases their utility. In this paper we argue that the journalistic metaphor can be effectively used to automatically generate multimedia presentations that help non-expert users analyze and understand sensor data. The journalistic layout and style are familiar to most users. Furthermore, the journalistic approach of ordering information from most general to most specific helps users obtain a high-level understanding while providing them the freedom to choose the depth of analysis to which they want to go. We describe the general characteristics and architectural requirements for an interactive intelligent user interface for exploring sensor data that uses the journalistic metaphor. We also describe our experience in developing this interface in real-world domains (e.g., hydrology).

Application of virtual certification techniques to vehicle design and track maintenance

Virtual certification partially substitutes by computer simulations the experimental techniques required for rail vehicle certification. In this paper, several works were these techniques were used in the vehicle design and track maintenance processes are presented. Dynamic simulation of multibody systems was used to virtually apply the EN14363 standard to certify the dynamic behaviour of vehicles. The works described are: assessment of a freight bogie design adapted to meter-gauge, assessment of a railway track layout for a subway network, freight bogie design with higher speed and axle load, and processing of the data acquired by a track recording vehicle for track maintenance.

Sistema de comunicaciones para una planta fotovoltaica

Las plantas solares fotovoltaicas, que son cada vez más habituales en nuestra sociedad, necesitan contar con un sistema de comunicaciones que permita la monitorización continua del funcionamiento de los diferentes equipos así como el control remoto de los mismos y la regulación de la producción. En este Proyecto se ha estudiado la estructura eléctrica y constructiva de una planta fotovoltaica genérica, prestando especial atención a los requerimientos que debe reunir el sistema de comunicaciones. El diseño del sistema de comunicaciones se ha realizado sobre una planta solar ficticia aún sin construir analizando su estructura sobre plano y aproximando la topología de red que se necesita implementar. Partiendo de esta estructura y de las cualidades de este tipo de instalaciones se ha realizado un análisis de las tecnologías disponibles, optando por una solución inalámbrica mixta, utilizando enlaces WiMAX y WiFi, manteniendo tecnología cableada únicamente para interconexión cercana de equipos. Esta elección se ha realizado con la intención de dotar a la planta de un sistema fiable, robusto y flexible sin descuidar el factor económico; para eso se ha cuidado la selección de equipamiento, su disposición en la planta y su configuración básica de funcionamiento. A partir de la solución definitiva se ha obtenido un presupuesto económico de la instalación. Se ha completado el diseño mediante simulaciones radioeléctricas, para asegurar un correcto funcionamiento de los diferentes enlaces. The photovoltaic solar power plants, which are becoming more common in our society, need a communications system that allowing continuous monitoring of the operation of the different devices as well as their remote control and regulation of the production. In this Project, electrical structure and construction of a generic photovoltaic solar plant have been studied, paying special attention to the essential requirements which must be fulfilled by the communication system. The communication system design is was carried out assuming that photovoltaic solar plant is fictitious and before its construction, analysing its structure over site plan and approximating the net topology in order to implement it. The analysis of the available technologies was performed basing on this structure as well as the qualities of this kind of facilities. As a result, a wireless mix option with WIMAX and WiFi links was chosen, using cable technology only to the close interconnection between equipments. This choice was made with the intention of giving the plant with a reliable, robust and flexible system without neglecting the economic factor, so that, the selection of equipment, the layout at the plant and operating basic configuration have been paid great attention. From the final solution is obtained a financial budget of the facility. Design is completed by radioelectric simulations to ensure the operation of the several links properly.

Las presentaciones de trabajo en lengua inglesa: una propuesta de curso on-line.

Desde la explosión de crecimiento de internet que comenzó en los años 90, se han ido creando y poniendo a disposición de los usuarios diversas herramientas para compartir información y servicios de diversas formas, desde el nacimiento del primer navegador hasta nuestros días, donde hay infinidad de lenguajes aplicables al ámbito web. En esta fase de crecimiento, en primer lugar, de cara a usuarios individuales, saldrían herramientas que permitirían a cada cual hacer su web personal, con sus contenidos expuestos. Más adelante se fue generando el fenómeno “comunidad”, con, por ejemplo, foros, o webs en las que había múltiples usuarios que disfrutaban de contenidos o servicios que la web ofreciese. Este crecimiento del mundo web en lo comunitario ha avanzado en muchas ramas,entre ellas, por supuesto, la educacional, surgiendo plataformas como la que es base del proyecto que a continuación se presenta, y herramienta básica y prácticamente ya imprescindible en la enseñanza universitaria: Moodle. Moodle es una herramienta diseñada para compatir recursos y diseñar actividades para el usuario potencial, complementando su aprendizaje en aula, o incluso siendo una vía autónoma de aprendizaje en sí misma. Se ha realizado un estudio sobre el estado de saludo de los contenidos que se exponen en Moodle, y se ha encontrado que una gran mayoría de los cursos que se pueden visitar tienen un gran número de carencias. Por un lado, hay pocos con material original explotado exclusivamente para el curso, y, si tienen material original, no se ha observado una especial atención por la maquetación. Por otro lado, hay muchos otros sin material original, y, en ambos casos, no se ha encontrado ningún curso que ofrezca material audiovisual exclusivo para el curso, presentando algunos en su lugar material audiovisual encontrado en la red (Youtube, etc). A la vista de estos hechos, se ha realizado un proyecto que intenta aportar soluciones ante estas carencias, y se presenta un curso procedente de diversas referencias bibliográficas, para la parte textual, y material audiovisual original e inédito que también se ha explotado específicamente para este curso. Este material ha sido por un lado vídeo, que se ha visionado, editado y subtitulado con software de libre distribución, y por otro lado, audio, que complementa un completo glosario que se ha añadido como extra al curso y cuyo planteamiento no se ha encontrado en ningún curso online de los revisados. Todo esto se ha envuelto en una maquetación cuidada que ha sido fruto del estudio de los lenguajes web html y CSS, de forma que, por un lado, el curso sea un lugar agradable en el que aprender dentro de internet, y por otro, se pudiesen realizar ciertas operaciones que sin estos conocimientos habrían sido imposibles, como la realización del glosario o la incrustación de imágenes y vídeos. A su vez, se ha tratado de dar un enfoque didáctico a toda la memoria del proyecto, de forma que pueda ser de utilidad a un usuario futuro que quisiese profundizar en los usos de Moodle, introducirse en el lenguaje web, o introducirse en el mundo de la edición de vídeo. ABSTRACT: Since the explosion of Internet growth beginning in the 90s, many tools have been created and made available for users to share information and services in various ways, from the birth of the first browser until today, where there are plenty of web programming languages. This growth stage would give individual users tools that would allow everyone to make an own personal website, with their contents exposed. Later, the "community" phenomenon appeared with, for example, forums, or websites where multiple users enjoyed the content or web services that those websites offered. Also, this growth in the web community world has progressed in many fields, including education, with the emerge of platforms such as the one that this project uses as its basis, and which is the basic and imperative tool in college education: Moodle. Moodle is a tool designed to share resources and design activities for the potential user, completing class learning, or even letting this user learn in an autonomous way. In this project a study on the current situation of the content present in Moodle courses around the net has been carried out, and it has been found that most of them lack of original material exploited exclusively for the courses, and if they have original material, there has been not observed concern on the layout where that material lies. On the other hand, there are many other with non original material, and in both cases, there has not been found any course that offers audio- visual material made specifically for the course, instead of presenting some audiovisual material found on the net (Youtube, etc). In view of these facts, the project presented here seeks to provide solutions to these shortcomings, presenting a course with original material exploited from various references, and unpublished audioevisual material which also has been exploited specifically for this course. This material is, on one hand, video, which has been viewed, edited and subtitled with free software, and on the other, audio, which complements a comprehensive glossary that has been added as an extra feature to the course and whose approach was not found in any of the online courses reviewed. All of this has been packaged in a neat layout that has been the result of the study of web languages HTML and CSS, so that first, the course was a pleasant place to learn on the internet, and second, certain operations could be performed which without this knowledge would have been impossible, as the glossary design or embedding images and videos. Furthermore, a didactic approach has been adopted to the entire project memory, so it can be useful to a future user who wanted to go deeper on the uses of Moodle, containing an intro into the web language, or in the world video editing.

A new module system for prolog

It is now widely accepted that separating programs into modules is useful in program development and maintenance. While many Prolog implementations include useful module systems, we argüe that these systems can be improved in a number of ways, such as, for example, being more amenable to effective global analysis and transformation and allowing sepárate compilation or sensible creation of standalone executables. We discuss a number of issues related to the design of such an improved module system for Prolog and propose some novel solutions. Based on this, we present the choices made in the Ciao module system, which has been designed to meet a number of objectives: allowing sepárate compilation, extensibility in features and in syntax, amenability to modular global analysis and transformation, enhanced error detection, support for meta-programming and higher-order, compatibility to the extent possible with official and de-facto standards, etc.

Contradictio in terminis: dialéctica de la ambigüedad en la arquitectura contemporánea

The twentieth century brought a new sensibility characterized by the discredit of cartesian rationality and the weakening of universal truths, related with aesthetic values as order, proportion and harmony. In the middle of the century, theorists such as Theodor Adorno, Rudolf Arnheim and Anton Ehrenzweig warned about the transformation developed by the artistic field. Contemporary aesthetics seemed to have a new goal: to deny the idea of art as an organized, finished and coherent structure. The order had lost its privileged position. Disorder, probability, arbitrariness, accidentality, randomness, chaos, fragmentation, indeterminacy... Gradually new terms were coined by aesthetic criticism to explain what had been happening since the beginning of the century. The first essays on the matter sought to provide new interpretative models based on, among other arguments, the phenomenology of perception, the recent discoveries of quantum mechanics, the deeper layers of the psyche or the information theories. Overall, were worthy attempts to give theoretical content to a situation as obvious as devoid of founding charter. Finally, in 1962, Umberto Eco brought together all this efforts by proposing a single theoretical frame in his book Opera Aperta. According to his point of view, all of the aesthetic production of twentieth century had a characteristic in common: its capacity to express multiplicity. For this reason, he considered that the nature of contemporary art was, above all, ambiguous. The aim of this research is to clarify the consequences of the incorporation of ambiguity in architectural theoretical discourse. We should start making an accurate analysis of this concept. However, this task is quite difficult because ambiguity does not allow itself to be clearly defined. This concept has the disadvantage that its signifier is as imprecise as its signified. In addition, the negative connotations that ambiguity still has outside the aesthetic field, stigmatizes this term and makes its use problematic. Another problem of ambiguity is that the contemporary subject is able to locate it in all situations. This means that in addition to distinguish ambiguity in contemporary productions, so does in works belonging to remote ages and styles. For that reason, it could be said that everything is ambiguous. And that’s correct, because somehow ambiguity is present in any creation of the imperfect human being. However, as Eco, Arnheim and Ehrenzweig pointed out, there are two major differences between current and past contexts. One affects the subject and the other the object. First, it’s the contemporary subject, and no other, who has acquired the ability to value and assimilate ambiguity. Secondly, ambiguity was an unexpected aesthetic result in former periods, while in contemporary object it has been codified and is deliberately present. In any case, as Eco did, we consider appropriate the use of the term ambiguity to refer to the contemporary aesthetic field. Any other term with more specific meaning would only show partial and limited aspects of a situation quite complex and difficult to diagnose. Opposed to what normally might be expected, in this case ambiguity is the term that fits better due to its particular lack of specificity. In fact, this lack of specificity is what allows to assign a dynamic condition to the idea of ambiguity that in other terms would hardly be operative. Thus, instead of trying to define the idea of ambiguity, we will analyze how it has evolved and its consequences in architectural discipline. Instead of trying to define what it is, we will examine what its presence has supposed in each moment. We will deal with ambiguity as a constant presence that has always been latent in architectural production but whose nature has been modified over time. Eco, in the mid-twentieth century, discerned between classical ambiguity and contemporary ambiguity. Currently, half a century later, the challenge is to discern whether the idea of ambiguity has remained unchanged or have suffered a new transformation. What this research will demonstrate is that it’s possible to detect a new transformation that has much to do with the cultural and aesthetic context of last decades: the transition from modernism to postmodernism. This assumption leads us to establish two different levels of contemporary ambiguity: each one related to one these periods. The first level of ambiguity is widely well-known since many years. Its main characteristics are a codified multiplicity, an interpretative freedom and an active subject who gives conclusion to an object that is incomplete or indefinite. This level of ambiguity is related to the idea of indeterminacy, concept successfully introduced into contemporary aesthetic language. The second level of ambiguity has been almost unnoticed for architectural criticism, although it has been identified and studied in other theoretical disciplines. Much of the work of Fredric Jameson and François Lyotard shows reasonable evidences that the aesthetic production of postmodernism has transcended modern ambiguity to reach a new level in which, despite of the existence of multiplicity, the interpretative freedom and the active subject have been questioned, and at last denied. In this period ambiguity seems to have reached a new level in which it’s no longer possible to obtain a conclusive and complete interpretation of the object because it has became an unreadable device. The postmodern production offers a kind of inaccessible multiplicity and its nature is deeply contradictory. This hypothetical transformation of the idea of ambiguity has an outstanding analogy with that shown in the poetic analysis made by William Empson, published in 1936 in his Seven Types of Ambiguity. Empson established different levels of ambiguity and classified them according to their poetic effect. This layout had an ascendant logic towards incoherence. In seventh level, where ambiguity is higher, he located the contradiction between irreconcilable opposites. It could be said that contradiction, once it undermines the coherence of the object, was the better way that contemporary aesthetics found to confirm the Hegelian judgment, according to which art would ultimately reject its capacity to express truth. Much of the transformation of architecture throughout last century is related to the active involvement of ambiguity in its theoretical discourse. In modern architecture ambiguity is present afterwards, in its critical review made by theoreticians like Colin Rowe, Manfredo Tafuri and Bruno Zevi. The publication of several studies about Mannerism in the forties and fifties rescued certain virtues of an historical style that had been undervalued due to its deviation from Renacentist canon. Rowe, Tafuri and Zevi, among others, pointed out the similarities between Mannerism and certain qualities of modern architecture, both devoted to break previous dogmas. The recovery of Mannerism allowed joining ambiguity and modernity for first time in the same sentence. In postmodernism, on the other hand, ambiguity is present ex-professo, developing a prominent role in the theoretical discourse of this period. The distance between its analytical identification and its operational use quickly disappeared because of structuralism, an analytical methodology with the aspiration of becoming a modus operandi. Under its influence, architecture began to be identified and studied as a language. Thus, postmodern theoretical project discerned between the components of architectural language and developed them separately. Consequently, there is not only one, but three projects related to postmodern contradiction: semantic project, syntactic project and pragmatic project. Leading these projects are those prominent architects whose work manifested an especial interest in exploring and developing the potential of the use of contradiction in architecture. Thus, Robert Venturi, Peter Eisenman and Rem Koolhaas were who established the main features through which architecture developed the dialectics of ambiguity, in its last and extreme level, as a theoretical project in each component of architectural language. Robert Venturi developed a new interpretation of architecture based on its semantic component, Peter Eisenman did the same with its syntactic component, and also did Rem Koolhaas with its pragmatic component. With this approach this research aims to establish a new reflection on the architectural transformation from modernity to postmodernity. Also, it can serve to light certain aspects still unaware that have shaped the architectural heritage of past decades, consequence of a fruitful relationship between architecture and ambiguity and its provocative consummation in a contradictio in terminis. Esta investigación centra su atención fundamentalmente sobre las repercusiones de la incorporación de la ambigüedad en forma de contradicción en el discurso arquitectónico postmoderno, a través de cada uno de sus tres proyectos teóricos. Está estructurada, por tanto, en torno a un capítulo principal titulado Dialéctica de la ambigüedad como proyecto teórico postmoderno, que se desglosa en tres, de títulos: Proyecto semántico. Robert Venturi; Proyecto sintáctico. Peter Eisenman; y Proyecto pragmático. Rem Koolhaas. El capítulo central se complementa con otros dos situados al inicio. El primero, titulado Dialéctica de la ambigüedad contemporánea. Una aproximación realiza un análisis cronológico de la evolución que ha experimentado la idea de la ambigüedad en la teoría estética del siglo XX, sin entrar aún en cuestiones arquitectónicas. El segundo, titulado Dialéctica de la ambigüedad como crítica del proyecto moderno se ocupa de examinar la paulatina incorporación de la ambigüedad en la revisión crítica de la modernidad, que sería de vital importancia para posibilitar su posterior introducción operativa en la postmodernidad. Un último capítulo, situado al final del texto, propone una serie de Proyecciones que, a tenor de lo analizado en los capítulos anteriores, tratan de establecer una relectura del contexto arquitectónico actual y su evolución posible, considerando, en todo momento, que la reflexión en torno a la ambigüedad todavía hoy permite vislumbrar nuevos horizontes discursivos. Cada doble página de la Tesis sintetiza la estructura tripartita del capítulo central y, a grandes rasgos, la principal herramienta metodológica utilizada en la investigación. De este modo, la triple vertiente semántica, sintáctica y pragmática con que se ha identificado al proyecto teórico postmoderno se reproduce aquí en una distribución específica de imágenes, notas a pie de página y cuerpo principal del texto. En la columna de la izquierda están colocadas las imágenes que acompañan al texto principal. Su distribución atiende a criterios estéticos y compositivos, cualificando, en la medida de lo posible, su condición semántica. A continuación, a su derecha, están colocadas las notas a pie de página. Su disposición es en columna y cada nota está colocada a la misma altura que su correspondiente llamada en el texto principal. Su distribución reglada, su valor como notación y su posible equiparación con una estructura profunda aluden a su condición sintáctica. Finalmente, el cuerpo principal del texto ocupa por completo la mitad derecha de cada doble página. Concebido como un relato continuo, sin apenas interrupciones, su papel como responsable de satisfacer las demandas discursivas que plantea una investigación doctoral está en correspondencia con su condición pragmática.

A new module system for prolog

It is now widely accepted that separating programs into modules has proven very useful in program development and maintenance. While many Prolog implementations include useful module systems, we feel that these systems can be improved in a number of ways, such as, for example, being more amenable to effective global analysis and allowing sepárate compilation or sensible creation of standalone executables. We discuss a number of issues related to the design of such an improved module system for Prolog. Based on this, we present the choices made in the Ciao module system, which has been designed to meet a number of objectives: allowing sepárate compilation, extensibility in features and in syntax, amenability to modular global analysis, etc.

Sequential origin in the high performance properties of spider dragline silk

Major ampullate (MA) dragline silk supports spider orb webs, combining strength and extensibility in the toughest biomaterial. MA silk evolved ~376 MYA and identifying how evolutionary changes in proteins influenced silk mechanics is crucial for biomimetics, but is hindered by high spinning plasticity. We use supercontraction to remove that variation and characterize MA silk across the spider phylogeny. We show that mechanical performance is conserved within, but divergent among, major lineages, evolving in correlation with discrete changes in proteins. Early MA silk tensile strength improved rapidly with the origin of GGX amino acid motifs and increased repetitiveness. Tensile strength then maximized in basal entelegyne spiders, ~230 MYA. Toughness subsequently improved through increased extensibility within orb spiders, coupled with the origin of a novel protein (MaSp2). Key changes in MA silk proteins therefore correlate with the sequential evolution high performance orb spider silk and could aid design of biomimetic fibers.

ARGoS: a modular, multi-engine simulator for heterogeneous swarm robotics

We present ARGoS, a novel open source multi-robot simulator. The main design focus of ARGoS is the real-time simulation of large heterogeneous swarms of robots. Existing robot simulators obtain scalability by imposing limitations on their extensibility and on the accuracy of the robot models. By contrast, in ARGoS we pursue a deeply modular approach that allows the user both to easily add custom features and to allocate computational resources where needed by the experiment. A unique feature of ARGoS is the possibility to use multiple physics engines of different types and to assign them to different parts of the environment. Robots can migrate from one engine to another transparently. This feature enables entirely novel classes of optimizations to improve scalability and paves the way for a new approach to parallelism in robotics simulation. Results show that ARGoS can simulate about 10,000 simple wheeled robots 40% faster than real-time.

A comparative study of SISO and MIMO control strategies for floor vibration damping

Civil engineering structures such as floor systems with open-plan layout or lightweight footbridges are susceptible to excessive level of vibrations caused by human loading. Active vibration control (AVC) via inertial mass actuators has been shown to be a viable technique to mitigate vibrations, allowing structures to satisfy vibration serviceability limits. Most of the AVC applications involve the use of SISO (single input single-output) strategies based on collocated control. However, in the case of floor structures, in which mostof the vibration modes are locally spatially distributed, SISO or multi-SISO strategies are quite inefficient. In this paper, a MIMO (multi-inputs multi-outputs) control in decentralised and centralised configuration is designed. The design process simultaneously finds the placement of multiple actuators and sensors and the output feedback gains. Additionally, actuator dynamics, actuator nonlinearities and frequency and time weightings are considered into the design process. Results with SISO and decentralised and centralised MIMO control (for a given number of actuators and sensors) are compared, showing the advantages of MIMO control for floor vibration control.