Desarrollo de una torre mixta de 100 metros de altura para un aerogenerador de 2MW de potencia

La tendencia del mercado eólico mundial es incrementar la potencia de los equipos de generación a través de la captación de mayores y más estables velocidades de viento, mayores diámetros de rotor y consecuentemente torres de mayor altura. El objetivo de este trabajo es presentar los fundamentos de diseño de una variante de construcción mixta de torres de cien metros de altura, la innovación de un sistema de fundación anular y el impacto económico que podría significar la implementación del conjunto. En primer término se describen los criterios de optimización del sistema de fundación y posteriormente el análisis estructural del tramo de torre en hormigón, realizado bajo lineamientos de normativa internacional y con la asistencia del método de elementos finitos. Por último se exponen en contraste los costos estimados de la alternativa propuesta y de una opción existente íntegramente realizada en hormigón.The global wind market trend is to increase the equipment power generation through the uptake of higher and more stable wind speeds, larger rotor diameters and consequently taller towers. The aim of this paper is to present the basics of design of a mixed tower variant of hundred meters high, the innovation of a ring foundation system and the economic impact that the implementation of the whole set could mean. First are described the optimization criteria of the foundation system and subsequently the structural analysis of the concrete tower part, performed under the guidelines of international standards and with the assistance of finite element method. Finally it is presented the estimated costs of the proposed alternative in contrast with an existing entirely concrete made option.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Preliminary Approach for a Prototype of Sustainable Antiseismic Dwelling in Nepal Based on the Historic Vernacular Tradition

The effects of the 2015 Gorkha earthquake in Nepal revealed deficiencies in the most recent vernacular architecture, which no longer uses wooden reinforcements due to national anti-deforestation laws. It also highlighted the shortcomings found in reinforced concrete architecture, which is generally scanty and poorly reinforced due to the high import cost of construction steel. The geography of Nepal has led to the development of a wide variety of vernacular architecture using local materials such as stone, brick or earth in the form of rammed earth and adobe walls [1]. Moreover, although its tradition in the construction of vaults is not as prominent as in neighbouring regions of India, Nepal has developed its own tradition in the construction of vaults and domes, which are generally self-supporting and made of brick or adobe with lime mortar. The design of a prototype of seismic house in Nepal aims to use a modular housing unit with rammed earth walls and/or walls made of materials recycled from previous earthquakes, as well as tile vaults with bamboo sleepers, and possibly vegetable fibre grids. These avoid the use of imported materials, favouring km0 and sustainable materials while following local tradition. Several potential housing units have undergone linear seismic analysis on finite element models, with variations in planimetric layout and the types of tile vault, from the simpler barrel vault to the sail vault. Both are analysed searching for the best shape in terms of seismic efficiency, evaluating stress and strain state. The results obtained from this preliminary study clearly show that, under seismic actions, the response from the construction system using depressed sail vaults and rammed earth walls with bamboo reinforcements is more efficient and homogeneous in terms of tension and deformation. This is due to the geometric symmetry which determines the same response in several directions, unlike vaults with a characteristically strong directionality (barrel vault). The seismic response of the prototype described is examined by assessing the influence in terms of thrust and deformation of bamboo reinforcements inside the walls. For this, laboratory tests are used to identify the mechanical characteristics of bamboo to be employed in the finite element modelling and calculation, as the values found in the literature vary depending on the physical and chemical characteristics of the material. This study therefore proposes a more sustainable architectural model with greater antiseismic resistance, always in keeping with local constructive tradition

Oval Domes: History, Geometry and Mechanics

An oval dome may be defined as a dome whose plan or profile (or both) has an oval form. The word Aoval@ comes from the latin Aovum@, egg. Then, an oval dome has an egg-shaped geometry. The first buildings with oval plans were built without a predetermined form, just trying to close an space in the most economical form. Eventually, the geometry was defined by using arcs of circle with common tangents in the points of change of curvature. Later the oval acquired a more regular form with two axis of symmetry. Therefore, an “oval” may be defined as an egg-shaped form, doubly symmetric, constructed with arcs of circle; an oval needs a minimum of four centres, but it is possible also to build polycentric ovals. The above definition corresponds with the origin and the use of oval forms in building and may be applied without problem until, say, the XVIIIth century. Since then, the teaching of conics in the elementary courses of geometry made the cultivated people to define the oval as an approximation to the ellipse, an “imperfect ellipse”: an oval was, then, a curve formed with arcs of circles which tries to approximate to the ellipse of the same axes. As we shall see, the ellipse has very rarely been used in building. Finally, in modern geometrical textbooks an oval is defined as a smooth closed convex curve, a more general definition which embraces the two previous, but which is of no particular use in the study of the employment of oval forms in building. The present paper contains the following parts: 1) an outline the origin and application of the oval in historical architecture; 2) a discussion of the spatial geometry of oval domes, i. e., the different methods employed to trace them; 3) a brief exposition of the mechanics of oval arches and domes; and 4) a final discussion of the role of Geometry in oval arch and dome design

Omega-3 supplementation in patients with sepsis: a systematic review and meta-analysis of randomized trials.

BACKGROUND: Nutritional supplementation of omega-3 fatty acids has been proposed to modulate the balance of pro- and anti-inflammatory mediators in sepsis. If proved to improve clinical outcomes in critically ill patients with sepsis, this intervention would be easy to implement. However, the cumulative evidence from several randomized clinical trials (RCTs) remains unclear. METHODS: We searched the Cochrane Library, MEDLINE, and EMBASE through December 2016 for RCTs on parenteral or enteral omega-3 supplementation in adult critically ill patients diagnosed with sepsis or septic shock. We analysed the included studies for mortality, intensive care unit (ICU) length of stay, and duration of mechanical ventilation, and used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the quality of the evidence for each outcome. RESULTS: A total of 17 RCTs enrolling 1239 patients met our inclusion criteria. Omega-3 supplementation compared to no supplementation or placebo had no significant effect on mortality [relative risk (RR) 0.85; 95% confidence interval (CI) 0.71, 1.03; P = 0.10; I (2) = 0%; moderate quality], but significantly reduced ICU length of stay [mean difference (MD) -3.79 days; 95% CI -5.49, -2.09; P < 0.0001, I (2) = 82%; very low quality] and duration of mechanical ventilation (MD -2.27 days; 95% CI -4.27, -0.27; P = 0.03, I (2) = 60%; very low quality). However, sensitivity analyses challenged the robustness of these results. CONCLUSION: Omega-3 nutritional supplementation may reduce ICU length of stay and duration of mechanical ventilation without significantly affecting mortality, but the very low quality of overall evidence is insufficient to justify the routine use of omega-3 fatty acids in the management of sepsis

Spanish version of the Satisfaction with Epilepsy Care questionnaire: Adaptation and psychometric properties

OBJECTIVE: The objective of this study was to perform a cross-cultural adaption and psychometric evaluation of the Spanish version of the Satisfaction with Epilepsy Care (SEC) questionnaire and analyze patient satisfaction with epilepsy care. METHODS: Transcultural adaptation and validation of the SEC were carried out using translation and back-translation with pilot testing and an expert panel. The SEC-E (Spanish) was analyzed in 213 patients with epilepsy to examine construct and criterion validity and internal consistency. RESULTS: The SEC-E achieved conceptual, semantic, and content equivalence with the original version. For content validity, one question was eliminated from the original questionnaire as it has little relevance in our cultural setting. Positive correlations for criterion validity were obtained using the gold standard measure (Satisfaction in Hospitalized Patients scale). Construct validity replicated the three dimensions of the original questionnaire. The scale showed adequate reliability through internal consistency (Cronbach's α of 0.94) and temporal stability on retest (n = 85). Patients scored (0 to 100) 77.5 [standard deviation (SD): 19.9] for satisfaction with communication, 76.9 (SD: 17) for organization, and 67.2 (SD: 22.1) for information. SIGNIFICANCE: The SEC-E is a valid and reliable tool for the assessment of educational interventions aiming to improve the quality of care in patients with epilepsy in Spanish clinical practice. The results showed a good level of patient satisfaction with epilepsy care

Oval Domes. The Case of the Basílica de la Virgen de los Desamparados of Valencia

[EN] The dome of the Basilica de la Virgen de los Desamparados of Valencia is an emblematic example of Valencian baroque architecture and painting. Its shape, oval or elliptical, has been the subject of controversy in various studies. The study of oval domes throughout history is a very interesting field of research because, among other things, the determination of the exact shape is important in order to conclude how it was built. We approach the problem from a new mathematical point of view, calculating the distances between the points that make up the real data cloud and the hypothetical form considered, oval or ellipse. The use of modern graphic surveying techniques, carried out with a 3D laser scanner, and computation with the powerful symbolic and numerical mathematical solver, Mathematica, has allowed us to accurately determine the shape of the dome and determine that its sections are not well-described by ellipses. A better fit is obtained assuming that sections are ovals. The programming and generalization of the mathematical method employed in this work will allow it to be applied to determine the exact geometry of other oval or ellipsoidal vaults.Calvo Roselló, V.; Capilla Tamborero, E.; Navarro Fajardo, JC. (2020). Oval Domes. The Case of the Basílica de la Virgen de los Desamparados of Valencia. Nexus Network Journal. 22(2):393-409. https://doi.org/10.1007/s00004-019-00465-0S393409222Arphe i Villafañe, Juan de. 1585. Tratado De varia conmmensuracion para la Escultura y Architectura. Sevilla: imprenta de Andrea Pescioni i Juan de León.Barrallo J. 2011. Ovals and Ellipses in Architecture. Proceedings of ISAMA 2011, Columbia College, Chicago, Illinois; p. 9–18.Bérchez Gómez, J. 1995. Basílica de Nuestra Señora de los Desamparados (Valencia). In: Monumentos de la Comunidad Valenciana. Catálogo de Monumentos declarados y conjuntos históricos incoados. Tomo X. Valencia. Arquitectura Religiosa. Valencia: Conselleria de Cultura, Educació i Ciència—Generalitat Valenciana, 204–217.Borngässer, B. 1997a. Arquitectura barroca en España y Portugal. In Toman R. (ed.) El barroco. Arquitectura-escultura-pintura. Köln: Könemann, 78–119.Borngässer, B. 1997b. Arquitectura barroca en Francia. In Toman R. (ed.) El barroco. Arquitectura-escultura-pintura. Köln: Könemann, 122–151.Bosch Reig, I., Roig Picazo, P. 1999. El proyecto de restauración arquitectónica de las cúpulas, tambor y linterna de la Basílica de la Virgen de los Desamparados de Valencia. In: Restauración de Pintura Mural aplicada a la Basílica de la Virgen de los Desamparados de Valencia, Roig Picazo, P. y Bosch Reig, I. Valencia: Servicio de Publicaciones de la U.P.V., 21–74.Calvo López, J., Alonso Rodríguez, M.A., Rabasa Díaz, E.; López Mozo, A. 2005. Cantería Renacentista en la Catedral de Murcia. Murcia: Colegio Oficial de Arquitectos.Capilla Tamborero E., Calvo Roselló, V. 2014. Chapter 8: La cúpula interior de la Basílica de la Virgen de los Desamparados de Valencia. Análisis geométrico y matemático. In: J. C. Navarro (ed.) Bóvedas Valencianas. Arquitecturas ideales, reales y virtuales en época medieval y moderna. Valencia: ed. UPV (Scientia), 196–237. ISBN: 978-84-9048-188-2.Connors, J. 1999. Un teorema sacro: San Carlo alle Quattro Fontane. In Il giovane Borromini. Dagli esordi a San Carlo alle Quattro Fontane. Milano: Skira, 459–512.Dotto, E. 2001. Note sulle costruzioni degli ovali a quattro centri. Vecchie e nuove costruzioni dell’ovale. Disegnare Idee Immagini; XII 23: 7–14.Duvernoy, Sylvie. 2015. Baroque Oval Churches: Innovative Geometrical Patterns in Early Modern Sacred Architecture. Nexus Network Journal 17 (2): 425–456.Fernández Gómez M. 1996. La planta oval. Traza y símbolo. Loggia. Arquitectura & Restauración 3: 16–21.García Jara F. 2008. Las cúpulas de la arquitectura religiosa de la provincia de Alicante: del Renacimiento al siglo XIX. Ph.D. Thesis.García Jara F. 2010. La estereotomía de las cúpulas sobre base oval. In: X Congreso Internacional de Expresión Gráfica aplicada a la Edificación, APEGA 2010, Alicante: 767–780.Gentil Baldrich, J. M. 1994. Planta oval y traza elíptica en la arquitectura: Consideraciones geométricas y un ejemplo español. Valladolid.Gentil Baldrich J.M. 1996. La traza oval y la Sala Capitular de la catedral de Sevilla. Una aproximación geométrica. In: J. A. Ruiz de la Rosa et al. Quatro edificios sevillanos. Sevilla: Colegio Oficial de Arquitectos de Andalucía, Demarcación Occidental, 73–147.Gómez-Collado, M.C.; Calvo Roselló, V; Capilla Tamborero, E. 2018. Mathematical modeling of oval arches. A study of the George V and Neuilly Bridges. Journal of Cultural Heritage Vol. 32: 144–155; https://doi.org/10.1016/j.culher.2018.01.012Hatch, John G. 2015. The Science Behind Francesco Borromini’s Divine Geometry. In: Architecture and Mathematics from Antiquity to the Future, eds. Kim Williams and Michael J. Oswald, vol. II, ch. 61, 217–228. Basel: Birkhäuser.Hill, Michael. 2013. Practical and Symbolic Geometry in Borromini’s San Carlo alle Quattro Fontane. Journal of the Society of Architectural Historians 72 (4): 555–583.Huerta Fernández, S. 2002. Informe sobre la estabilidad de la cúpula interior de la Basílica de la Virgen de los Desamparados de Valencia. Valencia. Conselleria Cultura, Educació y Ciència de la Generalitat Valenciana, 20 páginas.Huerta Fernández, S. 2007. Oval domes, geometry and mechanics. Nexus Network Journal 9(2), 211–248.Huerta Fernández, S. 2012a. Análisis estructural de cúpulas tabicadas: la cúpula interior de la Basílica de la Virgen de los Desamparados en Valencia. Construyendo Bóvedas Tabicadas. In: Actas del Simposio Internacional sobre bóvedas tabicadas. Valencia, 26 y 27 de mayo de 2011. Valencia: Editorial Universitat Politècnica de València, 318–335.Huerta Fernández, S. 2012b. Structural Analysis of Thin Tile Vaults and Domes: The Inner Oval Dome of the Basílica de la Virgen de los Desamparados in Valencia. In: Carvais et al (ed.) Nuts and Bolts of construction history. Culture, technology and society. Vol. 1. Paris: Picard, 375–383.Jung, W. 1997.) Arquitectura y ciudad en Italia. In Toman R. (ed.) El barroco. Arquitectura-escultura-pintura. Köln: Könemann, 12–75.Kluckert, E. 1997. Arquitectura barroca en Alemania, Suiza, Austria y Europa oriental. In Toman R. (ed.) El barroco. Arquitectura-escultura-pintura. Köln: Könemann, 184–273.López Manzanares, G. 2005. La contribución de R. G. Boscovich al desarrollo de la teoría de cúpulas: el informe sobre la Biblioteca Cesarea de Viena. In: Huerta, S. (ed.) Actas del Cuarto Congreso Nacional de Historia de la Construcción. Cádiz, 27–29 January 2005. Madrid: Instituto Juan de Herrera, 655–665.López Mozo A. 2011. Ovals for Any Given Proportion in Architecture: A Layout Possibly Known in the Sixteenth Century. Nexus Network Journal Vol. 13: 569–597.Mazzotti, A. 2014a. A Euclidean Approach to Eggs and Polycentric Curves. Nexus Network Journal, 16, 345–387. DOI https://doi.org/10.1007/s00004-014-0189-5Mazzotti, A. 2014b. What Borromini Might Have Known About Ovals. Ruler and Compass Constructions. Nexus Network Journal. https://doi.org/10.1007/s00004-014-0190-z .Mazzotti, A. 2017. All sides to an oval. Properties, Parameters, and Borromini’s Mysterious Construction. Springer. DOI https://doi.org/10.1007/978-3-319-39375-9Montoliu Soler, V. 2012. La Real Capilla de la Virgen de los Desamparados de Valencia: sus orígenes histórico-artísticos. Valencia: Real Academia de Cultura Valenciana.Navascués Palacio, P. 1974. El libro de arquitectura de Hernán Ruiz el Joven. Estudio y edición crítica por Pedro Navascues Palacio. Madrid: Escuela Técnica Superior de Arquitectura.Petrovic, Maja et al. 2019. A Focal Curve Approximation of a Borromini Oval Contour. Nexus Network Journal 21:19–31 https://doi.org/10.1007/s00004-018-00421-4Rabasa, E. 2009. Soluciones innecesariamente complicadas de la estereotomía clásica. In: AA.VV. El arte de la piedra, teoría y prática de la cantería. Madrid: CEU Ediciones, 50–69.Ragazzo, F. 1995, Geometria delle figure ovoidali, In Disegnare: 11, 17-24.Rosin P. 2001. On Serlio’s construction of ovals. The Mathematical Intelligencer 23(1): 58–69.Serlio S. 1552. Tercero y cuarto libro de Architectura de Sebastiano Serlio Boloñes. Translated by Francisco de Villalpando Architecto. Toledo: Casa de Iván de Ayala, 1552. (Edición facs. Barcelona: Serie Arte y Arquitectura, Editorial Alta Fulla, 1990.) (Edición digitalizada en Huerta, S. 2004. Selección de Tratados españoles de Arquitectura y Construcción de los siglos XVI al XX).Simona, M. 2005. Ovals in Borromini’s Geometry. In: Emmer, M., (ed.) Mathematics and Culture II. Visual Perfection: Mathematics and Creativity. Springer. 45–52. springeronline.comSoler Verdú, R. 1995. La cúpula en la arquitectura moderna valenciana. Siglos XVI a XVIII. Metodologías de estudios previos, para las arquitecturas de sistemas abovedados. Ph.D. Thesis. Universitat Politècnica de València.VV.AA. 2001. Real Basílica de la Virgen de los Desamparados de Valencia. Restauración de los fondos pictóricos y escultóricos. 1998–2001. I. Bosch (ed.) Valencia: Fundación para la Restauración de la Basílica de la Mare de Déu dels Desamparats

P and S velocity sturcture of the crust and the upper mantle beneath Central Java from local tomography inversion

Here we present the results of local source tomographic inversion beneath central Java. The data set was collected by a temporary seismic network. More than 100 stations were operated for almost half a year. About 13,000 P and S arrival times from 292 events were used to obtain three-dimensional (3-D) Vp, Vs, and Vp/Vs models of the crust and the mantle wedge beneath central Java. Source location and determination of the 3-D velocity models were performed simultaneously based on a new iterative tomographic algorithm, LOTOS-06. Final event locations clearly image the shape of the subduction zone beneath central Java. The dipping angle of the slab increases gradually from almost horizontal to about 70°. A double seismic zone is observed in the slab between 80 and 150 km depth. The most striking feature of the resulting P and S models is a pronounced low-velocity anomaly in the crust, just north of the volcanic arc (Merapi-Lawu anomaly (MLA)). An algorithm for estimation of the amplitude value, which is presented in the paper, shows that the difference between the fore arc and MLA velocities at a depth of 10 km reaches 30% and 36% in P and S models, respectively. The value of the Vp/Vs ratio inside the MLA is more than 1.9. This shows a probable high content of fluids and partial melts within the crust. In the upper mantle we observe an inclined low-velocity anomaly which links the cluster of seismicity at 100 km depth with MLA. This anomaly might reflect ascending paths of fluids released from the slab. The reliability of all these patterns was tested thoroughly

Theoretical Model for Cellular Shapes Driven by Protrusive and Adhesive Forces

The forces that arise from the actin cytoskeleton play a crucial role in determining the cell shape. These include protrusive forces due to actin polymerization and adhesion to the external matrix. We present here a theoretical model for the cellular shapes resulting from the feedback between the membrane shape and the forces acting on the membrane, mediated by curvature-sensitive membrane complexes of a convex shape. In previous theoretical studies we have investigated the regimes of linear instability where spontaneous formation of cellular protrusions is initiated. Here we calculate the evolution of a two dimensional cell contour beyond the linear regime and determine the final steady-state shapes arising within the model. We find that shapes driven by adhesion or by actin polymerization (lamellipodia) have very different morphologies, as observed in cells. Furthermore, we find that as the strength of the protrusive forces diminish, the system approaches a stabilization of a periodic pattern of protrusions. This result can provide an explanation for a number of puzzling experimental observations regarding cellular shape dependence on the properties of the extra-cellular matrix