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em AMS Tesi di Dottorato - Alm@DL - Università di Bologna


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I Max Bill is an intense giornata of a big fresco. An analysis of the main social, artistic and cultural events throughout the twentieth century is needed in order to trace his career through his masterpieces and architectures. Some of the faces of this hypothetical mural painting are, among others, Le Corbusier, Walter Gropius, Ernesto Nathan Rogers, Kandinskij, Klee, Mondrian, Vatongerloo, Ignazio Silone, while the backcloth is given by artistic avant-gardes, Bauhaus, International Exhibitions, CIAM, war events, reconstruction, Milan Triennali, Venice Biennali, the School of Ulm. Architect, even though more known as painter, sculptor, designer and graphic artist, Max Bill attends the Bauhaus as a student in the years 1927-1929, and from this experience derives the main features of a rational, objective, constructive and non figurative art. His research is devoted to give his art a scientific methodology: each work proceeds from the analysis of a problem to the logical and always verifiable solution of the same problem. By means of composition elements (such as rhythm, seriality, theme and its variation, harmony and dissonance), he faces, with consistent results, themes apparently very distant from each other as the project for the H.f.G. or the design for a font. Mathematics are a constant reference frame as field of certainties, order, objectivity: for Bill mathematics are never confined to a simple function: they represent a climate of spiritual certainties, and also the theme of non attempted in its purest state, objectivity of the sign and of the geometrical place, and at the same time restlessness of the infinity: Limited and Unlimited . In almost sixty years of activity, experiencing all artistic fields, Max Bill works, projects, designs, holds conferences and exhibitions in Europe, Asia and Americas, confronting himself with the most influencing personalities of the twentieth century. In such a vast scenery, the need to limit the investigation field combined with the necessity to address and analyse the unpublished and original aspect of Bills relations with Italy. The original contribution of the present research regards this particular geographic delimitation; in particular, beyond the deep cultural exchanges between Bill and a series of Milanese architects, most of all with Rogers, two main projects have been addressed: the realt nuova at Milan Triennale in 1947, and the Contemporary Art Museum in Florence in 1980. It is important to note that these projects have not been previously investigated, and the former never appears in the sources either. These works, together with the most well-known ones, such as the projects for the VI and IX Triennale, and the Swiss pavilion for the Biennale, add important details to the reference frame of the relations which took place between Zurich and Milan. Most of the occasions for exchanges took part in between the Thirties and the Fifties, years during which Bill underwent a significant period of artistic growth. He meets the Swiss progressive architects and the Paris artists from the Abstraction-Cration movement, enters the CIAM, collaborates with Le Corbusier to the third volume of his Complete Works, and in Milan he works and gets confronted with the events related to post-war reconstruction. In these years Bill defines his own working methodology, attaining an artistic maturity in his work. The present research investigates the mentioned time period, despite some necessary exceptions. II The official Max Bill bibliography is naturally wide, including spreading works along with ones more devoted to analytical investigation, mainly written in German and often translated into French and English (Max Bill himself published his works in three languages). Few works have been published in Italian and, excluding the catalogue of the Parma exhibition from 1977, they cannot be considered comprehensive. Many publications are exhibition catalogues, some of which include essays written by Max Bill himself, some others bring Bills comments in a educational-pedagogical approach, to accompany the observer towards a full understanding of the composition processes of his art works. Bill also left a great amount of theoretical speculations to encourage a critical reading of his works in the form of books edited or written by him, and essays published in Werk, magazine of the Swiss Werkbund, and other international reviews, among which Domus and Casabella. These three reviews have been important tools of analysis, since they include tracks of some of Max Bills architectural works. The architectural aspect is less investigated than the plastic and pictorial ones in all the main reference manuals on the subject: Benevolo, Tafuri and Dal Co, Frampton, Allenspach consider Max Bill as an artist proceeding in his work from Bauhaus in the Ulm experience . A first filing of his works was published in 2004 in the monographic issue of the Spanish magazine 2G, together with critical essays by Karin Gimmi, Stanislaus von Moos, Arthur Regg and Hans Frei, and in Konkrete Architektur?, again by Hans Frei. Moreover, the monographic essay on the Atelier Haus building by Arthur Regg from 1997, and the DPA 17 issue of the Catalonia Polytechnic with contributions of Carlos Mart, Bruno Reichlin and Ton Salvad, the latter publication concentrating on a few Bills themes and architectures. An urge to studying and going in depth in Max Bills works was marked in 2008 by the centenary of his birth and by a recent rediscovery of Bill as initiator of the minimalist tradition in Swiss architecture. Bills heirs are both very active in promoting exhibitions, researching and publishing. Jakob Bill, Max Bills son and painter himself, recently published a work on Bills experience in Bauhaus, and earlier on he had published an in-depth study on Endless Ribbons sculptures. Angela Thomas Schmid, Bills wife and art historian, published in end 2008 the first volume of a biography on Max Bill and, together with the film maker Eric Schmid, produced a documentary film which was also presented at the last Locarno Film Festival. Both biography and documentary concentrate on Max Bills political involvement, from antifascism and 1968 protest movements to Bill experiences as Zurich Municipality councilman and member of the Swiss Confederation Parliament. In the present research, the bibliography includes also direct sources, such as interviews and original materials in the form of letters correspondence and graphic works together with related essays, kept in the max+binia+jakob bill stiftung archive in Zurich. III The results of the present research are organized into four main chapters, each of them subdivided into four parts. The first chapter concentrates on the research field, reasons, tools and methodologies employed, whereas the second one consists of a short biographical note organized by topics, introducing the subject of the research. The third chapter, which includes unpublished events, traces the historical and cultural frame with particular reference to the relations between Max Bill and the Italian scene, especially Milan and the architects Rogers and Baldessari around the Fifties, searching the themes and the keys for interpretation of Bills architectures and investigating the critical debate on the reviews and the plastic survey through sculpture. The fourth and last chapter examines four main architectures chosen on a geographical basis, all devoted to exhibition spaces, investigating Max Bills composition process related to the pictorial field. Paintings has surely been easier and faster to investigate and verify than the building field. A doctoral thesis discussed in Lausanne in 1977 investigating Max Bills plastic and pictorial works, provided a series of devices which were corrected and adapted for the definition of the interpretation grid for the composition structures of Bills main architectures. Four different tools are employed in the investigation of each work: a context analysis related to chapter three results; a specific theoretical essay by Max Bill briefly explaining his main theses, even though not directly linked to the very same work of art considered; the interpretation grid for the composition themes derived from a related pictorial work; the architecture drawing and digital three-dimensional model. The double analysis of the architectural and pictorial fields is functional to underlining the relation among the different elements of the composition process; the two fields, however, cannot be compared and they stay, in Max Bills works as in the present research, interdependent though self-sufficient. IV An important aspect of Max Bill production is self-referentiality: talking of Max Bill, also through Max Bill, as a need for coherence instead of a method limitation. Ernesto Nathan Rogers describes Bill as the last humanist, and his horizon is the known world but, as the Concrete Art of which he is one of the main representatives, his production justifies itself: Max Bill not only found a method, but he autonomously re-wrote the rules of the game, derived timeless theoretical principles and verified them through a rich and interdisciplinary artistic production. The most recurrent words in the present research work are synthesis, unity, space and logic. These terms are part of Max Bills vocabulary and can be referred to his works. Similarly, graphic settings or analytical schemes in this research text referring to or commenting Bills architectural projects were drawn up keeping in mind the concise precision of his architectural design. As for Mies van der Rohe, it has been written that Max Bill took art to zero degree reaching in this way a high complexity. His works are a synthesis of art: they conceptually encompass all previous and considered their developments- most of contemporary pictures. Contents and message are generally explicitly declared in the title or in Bills essays on his artistic works and architectural projects: the beneficiary is invited to go through and re-build the process of synthesis generating the shape. In the course of the interview with the Milan artist Getulio Alviani, he tells how he would not write more than a page for an essay on Josef Albers: everything was already evident on the surface and any additional sentence would be redundant. Two years after that interview, these pages attempt to decompose and single out the elements and processes connected with some of Max Bills works which, for their own origin, already contain all possible explanations and interpretations. The formal reduction in favour of contents maximization is, perhaps, Max Bills main lesson.

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The hydrogen production in the green microalga Chlamydomonas reinhardtii was evaluated by means of a detailed physiological and biotechnological study. First, a wide screening of the hydrogen productivity was done on 22 strains of C. reinhardtii, most of which mutated at the level of the D1 protein. The screening revealed for the first time that mutations upon the D1 protein may result on an increased hydrogen production. Indeed, productions ranged between 0 and more than 500 mL hydrogen per liter of culture (Torzillo, Scoma et al., 2007a), the highest producer (L159I-N230Y) being up to 5 times more performant than the strain cc124 widely adopted in literature (Torzillo, Scoma, et al., 2007b). Improved productivities by D1 protein mutants were generally a result of high photosynthetic capabilities counteracted by high respiration rates. Optimization of culture conditions were addressed according to the results of the physiological study of selected strains. In a first step, the photobioreactor (PBR) was provided with a multiple-impeller stirring system designed, developed and tested by us, using the strain cc124. It was found that the impeller system was effectively able to induce regular and turbulent mixing, which led to improved photosynthetic yields by means of light/dark cycles. Moreover, improved mixing regime sustained higher respiration rates, compared to what obtained with the commonly used stir bar mixing system. As far as the results of the initial screening phase are considered, both these factors are relevant to the hydrogen production. Indeed, very high energy conversion efficiencies (light to hydrogen) were obtained with the impeller device, prooving that our PBR was a good tool to both improve and study photosynthetic processes (Giannelli, Scoma et al., 2009). In the second part of the optimization, an accurate analysis of all the positive features of the high performance strain L159I-N230Y pointed out, respect to the WT, it has: (1) a larger chlorophyll optical cross-section; (2) a higher electron transfer rate by PSII; (3) a higher respiration rate; (4) a higher efficiency of utilization of the hydrogenase; (5) a higher starch synthesis capability; (6) a higher per cell D1 protein amount; (7) a higher zeaxanthin synthesis capability (Torzillo, Scoma et al., 2009). These information were gathered with those obtained with the impeller mixing device to find out the best culture conditions to optimize productivity with strain L159I-N230Y. The main aim was to sustain as long as possible the direct PSII contribution, which leads to hydrogen production without net CO2 release. Finally, an outstanding maximum rate of 11.1 1.0 mL/L/h was reached and maintained for 21.8 7.7 hours, when the effective photochemical efficiency of PSII (F/F'm) underwent a last drop to zero. If expressed in terms of chl (24.0 2.2 moles/mg chl/h), these rates of production are 4 times higher than what reported in literature to date (Scoma et al., 2010a submitted). DCMU addition experiments confirmed the key role played by PSII in sustaining such rates. On the other hand, experiments carried out in similar conditions with the control strain cc124 showed an improved final productivity, but no constant PSII direct contribution. These results showed that, aside from fermentation processes, if proper conditions are supplied to selected strains, hydrogen production can be substantially enhanced by means of biophotolysis. A last study on the physiology of the process was carried out with the mutant IL. Although able to express and very efficiently utilize the hydrogenase enzyme, this strain was unable to produce hydrogen when sulfur deprived. However, in a specific set of experiments this goal was finally reached, pointing out that other than (1) a state 1-2 transition of the photosynthetic apparatus, (2) starch storage and (3) anaerobiosis establishment, a timely transition to the hydrogen production is also needed in sulfur deprivation to induce the process before energy reserves are driven towards other processes necessary for the survival of the cell. This information turned out to be crucial when moving outdoor for the hydrogen production in a tubular horizontal 50-liter PBR under sunlight radiation. First attempts with laboratory grown cultures showed that no hydrogen production under sulfur starvation can be induced if a previous adaptation of the culture is not pursued outdoor. Indeed, in these conditions the hydrogen production under direct sunlight radiation with C. reinhardtii was finally achieved for the first time in literature (Scoma et al., 2010b submitted). Experiments were also made to optimize productivity in outdoor conditions, with respect to the light dilution within the culture layers. Finally, a brief study of the anaerobic metabolism of C. reinhardtii during hydrogen oxidation has been carried out. This study represents a good integration to the understanding of the complex interplay of pathways that operate concomitantly in this microalga.

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Since the development of quantum mechanics it has been natural to analyze the connection between classical and quantum mechanical descriptions of physical systems. In particular one should expect that in some sense when quantum mechanical effects becomes negligible the system will behave like it is dictated by classical mechanics. One famous relation between classical and quantum theory is due to Ehrenfest. This result was later developed and put on firm mathematical foundations by Hepp. He proved that matrix elements of bounded functions of quantum observables between suitable coherents states (that depend on Planck's constant h) converge to classical values evolving according to the expected classical equations when h goes to zero. His results were later generalized by Ginibre and Velo to bosonic systems with infinite degrees of freedom and scattering theory. In this thesis we study the classical limit of Nelson model, that describes non relativistic particles, whose evolution is dictated by Schrdinger equation, interacting with a scalar relativistic field, whose evolution is dictated by Klein-Gordon equation, by means of a Yukawa-type potential. The classical limit is a mean field and weak coupling limit. We proved that the transition amplitude of a creation or annihilation operator, between suitable coherent states, converges in the classical limit to the solution of the system of differential equations that describes the classical evolution of the theory. The quantum evolution operator converges to the evolution operator of fluctuations around the classical solution. Transition amplitudes of normal ordered products of creation and annihilation operators between coherent states converge to suitable products of the classical solutions. Transition amplitudes of normal ordered products of creation and annihilation operators between fixed particle states converge to an average of products of classical solutions, corresponding to different initial conditions.

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La recente Direttiva 31/2010 dellUnione Europea impone agli stati membri di riorganizzare il quadro legislativo nazionale in materia di prestazione energetica degli edifici, affinch tutte le nuove costruzioni presentino dal 1 gennaio 2021 un bilancio energetico tendente allo zero; termine peraltro anticipato al 1 gennaio 2019 per gli edifici pubblici. La concezione di edifici a energia quasi zero (nZEB) parte dal presupposto di un involucro energeticamente di standard passivo per arrivare a compensare, attraverso la produzione preferibilmente in sito di energia da fonti rinnovabili, gli esigui consumi richiesti su base annuale. In questottica la riconsiderazione delle potenzialit dellarchitettura solare individua degli strumenti concreti e delle valide metodologie per supportare la progettazione di involucri sempre pi performanti che sfruttino pienamente una risorsa inesauribile, diffusa e alla portata di tutti come quella solare. Tutto ci in considerazione anche della non pi procrastinabile necessit di ridurre il carico energetico imputabile agli edifici, responsabili come noto di oltre il 40% dei consumi mondiali e del 24% delle emissioni di gas climalteranti. Secondo queste premesse la ricerca pone come centrale il tema dellintegrazione dei sistemi di guadagno termico, cosiddetti passivi, e di produzione energetica, cosiddetti attivi, da fonte solare nellinvolucro architettonico. Il percorso sia analitico che operativo effettuato si posto la finalit di fornire degli strumenti metodologici e pratici al progetto dellarchitettura, bisognoso di un nuovo approccio integrato mirato al raggiungimento degli obiettivi di risparmio energetico. Attraverso una ricognizione generale del concetto di architettura solare e dei presupposti teorici e terminologici che stanno alla base della stessa, la ricerca ha prefigurato tre tipologie di esito finale: una codificazione delle morfologie ricorrenti nelle realizzazioni solari, unanalisi comparata del rendimento solare nelle principali aggregazioni tipologiche edilizie e una parte importante di verifica progettuale dove sono stati applicati gli assunti delle categorie precedenti

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This thesis focuses on the energy efficiency in wireless networks under the transmission and information diffusion points of view. In particular, on one hand, the communication efficiency is investigated, attempting to reduce the consumption during transmissions, while on the other hand the energy efficiency of the procedures required to distribute the information among wireless nodes in complex networks is taken into account. For what concerns energy efficient communications, an innovative transmission scheme reusing source of opportunity signals is introduced. This kind of signals has never been previously studied in literature for communication purposes. The scope is to provide a way for transmitting information with energy consumption close to zero. On the theoretical side, starting from a general communication channel model subject to a limited input amplitude, the theme of low power transmission signals is tackled under the perspective of stating sufficient conditions for the capacity achieving input distribution to be discrete. Finally, the focus is shifted towards the design of energy efficient algorithms for the diffusion of information. In particular, the endeavours are aimed at solving an estimation problem distributed over a wireless sensor network. The proposed solutions are deeply analyzed both to ensure their energy efficiency and to guarantee their robustness against losses during the diffusion of information (against information diffusion truncation more in general).

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Il lavoro si propone come unindagine sulla letteratura italiana del primo decennio del XXI secolo, in una prospettiva non di semplice ricognizione ma di individuazione di linee interpretative capaci di ripercorrere un archivio di materiali molto vasto e non ancora chiuso. La prima parte affronta questioni relative a condizioni produttive, ricezione e valutazione critica della letteratura contemporanea. Il primo capitolo dedicato alla discussione di problemi relativi allo studio della narrativa italiana del XXI secolo a partire dalla definizione utilizzata per riferirsi ad essa, quella di anni zero. Il secondo capitolo situa la narrativa contemporanea nelle linee di sviluppo della letteratura italiana degli ultimi trentanni, a partire da un mutamento del rapporto dello scrittore con la tradizione umanistica che risale allinizio degli anni ottanta. Il terzo capitolo approfondisce uno dei generi maggiormente praticati: il romanzo storico. Considerato negli anni ottanta e novanta un genere d'evasione e intrattenimento, negli anni zero divenuto veicolo di punti di vista critici nei confronti delle narrazioni dominanti. La seconda parte dedicata allapprofondimento di romanzi che raccontano, da unottica non testimoniale, gli anni settanta italiani, periodo complesso non solo sul piano evenemenziale, ma anche su quello della rielaborazione artistica. I romanzi su cui si concentra lindagine offrono un racconto degli anni settanta italiani a partire da unidea di storia plurale, ricostruita attraverso una molteplicit di voci, che muta a seconda della prospettiva da cui viene affrontata. Le storie false dei romanzi sugli anni settanta non chiedono di essere lette come vere, ma dicono comunque qualcosa di vero sulle modalit attraverso le quali si va costruendo il rapporto con il passato recente, nel pi ampio contesto dei percorsi della letteratura italiana di inizio millennio, tra spinte che vanno nella direzione del mantenimento dellautonomia da parte degli autori e pressioni del mercato editoriale.