900 resultados para Modernism in art


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The basic hedonic hypothesis is that goods are valued for their utility-bearing characteristics and not for the good itself. Each attribute can be evaluated by consumers when making a purchasing decision and an implicit price can be identified for each of them. Thus, the observed price of a certain good can be analyzed as the sum of the implicit prices paid for each quality attribute. Literature has reported hedonic models estimates in the case of wines, which are excellent examples of differentiated goods worldwide.The impact of different wine attributes (intrinsic or extrinsic) on consumers’ willingness to pay has been analyzed with dissimilar results. Wines coming from "New World" producers seem to be appreciated for different attributes than wines produced in the "Old World". Moreover, "Old and New World" consumers seem to value differently the wine’s characteristics. To our knowledge, no cross country analysis has been done dealing with "New World" wines in "Old World" countries, leaving an important gap in understanding underlying attributes influencing buying decisions.

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New actuation technology in functional or "smart" materials has opened new horizons in robotics actuation systems. Materials such as piezo-electric fiber composites, electro-active polymers and shape memory alloys (SMA) are being investigated as promising alternatives to standard servomotor technology [52]. This paper focuses on the use of SMAs for building muscle-like actuators. SMAs are extremely cheap, easily available commercially and have the advantage of working at low voltages. The use of SMA provides a very interesting alternative to the mechanisms used by conventional actuators. SMAs allow to drastically reduce the size, weight and complexity of robotic systems. In fact, their large force-weight ratio, large life cycles, negligible volume, sensing capability and noise-free operation make possible the use of this technology for building a new class of actuation devices. Nonetheless, high power consumption and low bandwidth limit this technology for certain kind of applications. This presents a challenge that must be addressed from both materials and control perspectives in order to overcome these drawbacks. Here, the latter is tackled. It has been demonstrated that suitable control strategies and proper mechanical arrangements can dramatically improve on SMA performance, mostly in terms of actuation speed and limit cycles.

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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.

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The study of supply networks sustainability is a field with a long path behind. Nonetheless, most studies to date are focused on the environmental sub dimension of sustainability, while the social perspective in supply chain networks research still shows a potential for pioneering contri butions. Moreover, from the development standpoint we have observed a paradigm shift advancing from a narrow concept of development, centered on purely economic dimensions, towards more refined issues such as inclusive business, shared value or poverty footprint, all of which are highly related to supply chain activities. In this paper we present a review of the current state of the art on social sustainability of supply chains and we identify the main existing trends in this field. After conducting this study, we can state that a new sphere of knowledge is emerging at the interface between sustainable supply chain networks and development research. The academic community is called to play an important dovetailing role in this scenario by advancing both conceptual and methodological contributions.

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Isolated electrical systems lack electrical interconnection to other networks and are usually placed in geographically isolated areas—mainly islands or locations in developing countries. Until recently, only diesel generators were able to assure a safe and reliable supply in exchange for very high costs for fuel transportation and system operation. Transmission system operators (TSOs) are increasingly seeking to replace traditional energy models based on large groups of conventional generation units with mixed solutions where diesel groups are held as backup generation and important advantages are provided by renewable energy sources. The grid codes determine the technical requirements to be fulfilled by the generators connected in any electrical network, but regulations applied to isolated grids are more demanding. In technical literature it is rather easy to find and compare grid codes for interconnected electrical systems. However, the existing literature is incomplete and sparse regarding isolated grids. This paper aims to review the current state of isolated systems and grid codes applicable to them, specifying points of comparison and defining the guidelines to be followed by the upcoming regulations.

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Electrical power systems are changing their traditional structure, which was based on a little number of large generating power plants placed at great distances from loads by new models that tend to split the big production nodes in many smaller ones. The set of small groups which are located close to consumers and provide safe and quality energy is called distributed generation (DG). The proximity of the sources to the loads reduces losses associated with transportation and increases overall system efficiency. DG also favors the inclusion of renewable energy sources in isolated electrical systems or remote microgrids, because they can be installed where the natural resource is located. In both cases, as weak grids unable to get help from other nearby networks, it is essential to ensure appropriate behavior of DG sources to guarantee power system safety and stability. The grid codes sets out the technical requirements to be fulfilled for the sources connected in these electrical networks. In technical literature it is rather easy to find and compare grid codes for interconnected electrical systems. However, the existing literature is incomplete and sparse regarding isolated electrical systems and this happens due to the difficulties inherent in the pursuit of codes. Some countries have developed their own legislation only for their island territory (as Spain or France), others apply the same set of rules as in mainland, another group of island countries have elaborated a complete grid code for all generating sources and some others lack specific regulation. This paper aims to make a complete review of the state of the art in grid codes applicable to isolated systems, setting the comparison between them and defining the guidelines predictably followed by the upcoming regulations in these particular systems.

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Análisis de la situación actual de la planificación urbana en España