Leonardo da Vinci's Contributions from a Design Perspective

[EN] The figure of Leonardo da Vinci has been extensively studied. In fact, the Leonardiana Library brings together tens of thousands of titles on Leonardo and his work. During the second half of the 20th century, various treaties were published focusing on Leonardo¿s activity as an engineer, and more recently, an increasing number of scientific articles that focus on certain aspects of the prolific work of the genius such as construction, mechanics, strength of materials, etc. have been published. This article analyses the main contributions of the Tuscan genius in the field of design focusing on his processes for generating new solutions, his developments regarding graphic representation techniques, his improvements in plotting and measuring instruments, and how some of his devices were implemented and continue to maintain their usefulness.Cerveró-Meliá, E.; Capuz-Rizo, SF.; Ferrer-Gisbert, P. (2020). Leonardo da Vinci's Contributions from a Design Perspective. Designs. 4(3):1-20. https://doi.org/10.3390/designs4030038S12043Braha, D., & Maimon, O. (1997). The design process: properties, paradigms, and structure. IEEE Transactions on Systems, Man, and Cybernetics - Part A: Systems and Humans, 27(2), 146-166. doi:10.1109/3468.554679Criteria for Accrediting Engineering Programs, 2019–2020 https://www.abet.org/accreditation/accreditation-criteria/criteria-for-accrediting-engineering-programs-2019-2020/#definitionsVeltman, K. H. (2008). Leonardo da Vinci: A Review. Leonardo, 41(4), 381-388. doi:10.1162/leon.2008.41.4.381Innocenzi, P. (2020). Leonardo and the Design of Machines. Advances in Intelligent Systems and Computing, 36-46. doi:10.1007/978-3-030-41018-6_5Oliveira, A. R. E. (2019). The Mechanical Sciences in Leonardo da Vinci’s Work. Advances in Historical Studies, 08(05), 215-238. doi:10.4236/ahs.2019.85016Jaramillo, H. E. (2011). Un Análisis de la Resistencia de Materiales a partir de los Postulados de «Consideraciones y Demostraciones Matemáticas sobre dos Nuevas Ciencias» de Galileo Galilei. Lámpsakos, (5), 53. doi:10.21501/21454086.819Reciprocating machine for weight lifting (Argano), Codex Atlanticus f. 30 v, (1478–1480) https://commons.wikimedia.org/wiki/File:Reproduction_of_page_from_notebook_of_Leonardo_da_Vinci_showing_a_geared_device_assembled_and_disassembled_LCCN2006681098.jpgModel at the Museum of Science and Technology of Milan https://commons.wikimedia.org/wiki/File:Argano_sollevatore_pesi_Leonardo_Museo_scienza_e_tecnologia_Milano.jpgMap of the Val di Chiana, Royal Collection, RLW 12278, (1502–1504) https://commons.wikimedia.org/wiki/File:Val_di_Chiana.jpgReproduction of a compass designed by Leonardo https://commons.wikimedia.org/wiki/File:Compas_Léonard_de_Vinci.JPGProportional or reduction compass. Forster Codex I f. 45 (1485) https://commons.wikimedia.org/wiki/File:Reduction_Compass_Leonardo.jpgParabolic Compass. Codex Atlanticus f. 1093 r https://upload.wikimedia.org/wikipedia/commons/archive/0/03/20171027130237%21Leonardo_parabolic_compass.JPG.Detail of the Codex Atlanticus f. 5 r. Enlarged detail of the prospectograph being used by Leonardo https://commons.wikimedia.org/wiki/File:Codice_Atlantico_-_Perspectograph.jpgStudy ot two odometers. Codex Atlanticus, f. 1b r https://commons.wikimedia.org/wiki/File:Odomètre-Léonard.jpgOdometer model. Museo Nazionale della Scienza e della Tecnologia Leonardo da Vinci. (National Museum of Science and Technology of Milan) https://commons.wikimedia.org/wiki/File:Odometro_a_carriola_-_Museo_scienza_tecnologia_Milano_09908_01.jpgPugno, N. M. (2019). The commemoration of Leonardo da Vinci. Meccanica, 54(15), 2317-2324. doi:10.1007/s11012-019-01099-9Study for the mechanism of a manual lift (1495–1497), Madrid Codex I, f. 9 r https://commons.wikimedia.org/wiki/File:Ascenceur_à_manivelle-Léonard.jpgStudy of a piling machine. Codex Atlanticus, f 785, Ambrosian Library of Milan https://commons.wikimedia.org/wiki/File:Sonnette-Léonard.jpgModel of Leonardo’s pile machine, at the National Museum of Science and Technology of Milan https://commons.wikimedia.org/wiki/File:Battipalo_-_Museo_scienza_tecnologia_Milano_00040_01.jpgDetail of a mechanical jack, Codex Atlanticus, f. 0998 r, Ambrosian Library of Milan https://commons.wikimedia.org/wiki/File:Cric-Léonard.jpgManuscript of the self-propelled vehicle, Codex Atlanticus, f. 812 r (1478-1480), Ambrosiana Library of Milan https://commons.wikimedia.org/wiki/File:Leonardo_da_vinci,_Automobile.jpgModel of the self-propelled vehicle, at the National Museum of Science and Technology of Milan https://commons.wikimedia.org/wiki/File:Carro_semovente_-_Museo_scienza_tecnologia_Milano_09082_02.jp

Quasi-static Flow Model for Predicting the Extreme Values of Air Pocket Pressure in Draining and Filling Operations in Single Water Installations

[EN] Inertial models have been used by researchers to simulate the draining and filling processes in water pipelines, based on the evolution of the main hydraulic and thermodynamic variables. These models use complex differential equations, which are solved using advanced numerical codes. In this study, a quasi-static flow model is developed to study these operations in hydraulic installations. The quasi-static flow model represents a simplified formulation compared with inertial flow models, in which its numerical resolution is easier because only algebraic equations must be addressed. Experimental measurements of air pocket pressure patterns were conducted in a 4.36 m long single pipeline with an internal diameter of 42 mm. Comparisons between measured and computed air pocket pressure oscillations indicate how the quasi-static flow model can predict extreme values of air pocket pressure for experimental runs, demonstrating the possibility of selecting stiffness and pipe classes in actual pipelines using this model. Two case studies were analysed to determine the behaviour of the quasi-static flow model in large water pipelines.This research and the APC were funded by the Comision Nacional de Investigacion Cientifica y Tecnologica (Conicyt), grant number 1180660.Coronado-Hernández, ÓE.; Fuertes-Miquel, VS.; Mora-Meliá, D.; Salgueiro, Y. (2020). Quasi-static Flow Model for Predicting the Extreme Values of Air Pocket Pressure in Draining and Filling Operations in Single Water Installations. Water. 12(3):1-16. https://doi.org/10.3390/w12030664S116123Abreu, J., Cabrera, E., Izquierdo, J., & García-Serra, J. (1999). Flow Modeling in Pressurized Systems Revisited. Journal of Hydraulic Engineering, 125(11), 1154-1169. doi:10.1061/(asce)0733-9429(1999)125:11(1154)Izquierdo, J., Fuertes, V. S., Cabrera, E., Iglesias, P. L., & Garcia-Serra, J. (1999). Pipeline start-up with entrapped air. Journal of Hydraulic Research, 37(5), 579-590. doi:10.1080/00221689909498518Simpson, A. R., & Wylie, E. B. (1991). Large Water‐Hammer Pressures for Column Separation in Pipelines. Journal of Hydraulic Engineering, 117(10), 1310-1316. doi:10.1061/(asce)0733-9429(1991)117:10(1310)Zhou, L., Liu, D., Karney, B., & Wang, P. (2013). Phenomenon of White Mist in Pipelines Rapidly Filling with Water with Entrapped Air Pockets. Journal of Hydraulic Engineering, 139(10), 1041-1051. doi:10.1061/(asce)hy.1943-7900.0000765Zhou, L., & Liu, D. (2013). Experimental investigation of entrapped air pocket in a partially full water pipe. Journal of Hydraulic Research, 51(4), 469-474. doi:10.1080/00221686.2013.785985Coronado-Hernández, O., Fuertes-Miquel, V., Besharat, M., & Ramos, H. (2017). Experimental and Numerical Analysis of a Water Emptying Pipeline Using Different Air Valves. Water, 9(2), 98. doi:10.3390/w9020098Coronado-Hernández, Ó. E., Besharat, M., Fuertes-Miquel, V. S., & Ramos, H. M. (2019). Effect of a Commercial Air Valve on the Rapid Filling of a Single Pipeline: a Numerical and Experimental Analysis. Water, 11(9), 1814. doi:10.3390/w11091814Vasconcelos, J. G., & Wright, S. J. (2008). Rapid Flow Startup in Filled Horizontal Pipelines. Journal of Hydraulic Engineering, 134(7), 984-992. doi:10.1061/(asce)0733-9429(2008)134:7(984)Fuertes-Miquel, V. S., Coronado-Hernández, O. E., Iglesias-Rey, P. L., & Mora-Meliá, D. (2018). Transient phenomena during the emptying process of a single pipe with water–air interaction. Journal of Hydraulic Research, 57(3), 318-326. doi:10.1080/00221686.2018.1492465Fuertes-Miquel, V. S., Coronado-Hernández, O. E., Mora-Meliá, D., & Iglesias-Rey, P. L. (2019). Hydraulic modeling during filling and emptying processes in pressurized pipelines: a literature review. Urban Water Journal, 16(4), 299-311. doi:10.1080/1573062x.2019.1669188Besharat, M., Coronado-Hernández, O. E., Fuertes-Miquel, V. S., Viseu, M. T., & Ramos, H. M. (2018). Backflow air and pressure analysis in emptying a pipeline containing an entrapped air pocket. Urban Water Journal, 15(8), 769-779. doi:10.1080/1573062x.2018.1540711Besharat, M., Coronado-Hernández, O. E., Fuertes-Miquel, V. S., Viseu, M. T., & Ramos, H. M. (2019). Computational fluid dynamics for sub-atmospheric pressure analysis in pipe drainage. Journal of Hydraulic Research, 58(4), 553-565. doi:10.1080/00221686.2019.1625819Laanearu, J., Annus, I., Koppel, T., Bergant, A., Vučković, S., Hou, Q., … van’t Westende, J. M. C. (2012). Emptying of Large-Scale Pipeline by Pressurized Air. Journal of Hydraulic Engineering, 138(12), 1090-1100. doi:10.1061/(asce)hy.1943-7900.0000631Tijsseling, A. S., Hou, Q., Bozkuş, Z., & Laanearu, J. (2015). Improved One-Dimensional Models for Rapid Emptying and Filling of Pipelines. Journal of Pressure Vessel Technology, 138(3). doi:10.1115/1.4031508Malekpour, A., Karney, B. W., & Nault, J. (2016). Physical Understanding of Sudden Pressurization of Pipe Systems with Entrapped Air: Energy Auditing Approach. Journal of Hydraulic Engineering, 142(2), 04015044. doi:10.1061/(asce)hy.1943-7900.0001067Noto, L., & Tucciarelli, T. (2001). DORA Algorithm for Network Flow Models with Improved Stability and Convergence Properties. Journal of Hydraulic Engineering, 127(5), 380-391. doi:10.1061/(asce)0733-9429(2001)127:5(380)Zhou, L., Liu, D., & Ou, C. (2011). Simulation of Flow Transients in a Water Filling Pipe Containing Entrapped Air Pocket with VOF Model. Engineering Applications of Computational Fluid Mechanics, 5(1), 127-140. doi:10.1080/19942060.2011.11015357SaemI, S., Raisee, M., Cervantes, M. J., & Nourbakhsh, A. (2018). Computation of two- and three-dimensional water hammer flows. Journal of Hydraulic Research, 57(3), 386-404. doi:10.1080/00221686.2018.1459892Apollonio, C., Balacco, G., Fontana, N., Giugni, M., Marini, G., & Piccinni, A. (2016). Hydraulic Transients Caused by Air Expulsion During Rapid Filling of Undulating Pipelines. Water, 8(1), 25. doi:10.3390/w8010025Wang, L., Wang, F., Karney, B., & Malekpour, A. (2017). Numerical investigation of rapid filling in bypass pipelines. Journal of Hydraulic Research, 55(5), 647-656. doi:10.1080/00221686.2017.1300193Coronado-Hernández, O. E., Fuertes-Miquel, V. S., Besharat, M., & Ramos, H. M. (2018). Subatmospheric pressure in a water draining pipeline with an air pocket. Urban Water Journal, 15(4), 346-352. doi:10.1080/1573062x.2018.1475578Ramezani, L., Karney, B., & Malekpour, A. (2016). Encouraging Effective Air Management in Water Pipelines: A Critical Review. Journal of Water Resources Planning and Management, 142(12), 04016055. doi:10.1061/(asce)wr.1943-5452.0000695Martins, S. C., Ramos, H. M., & Almeida, A. B. (2015). Conceptual analogy for modelling entrapped air action in hydraulic systems. Journal of Hydraulic Research, 53(5), 678-686. doi:10.1080/00221686.2015.1077353Zhou, F., Hicks, F. E., & Steffler, P. M. (2002). Transient Flow in a Rapidly Filling Horizontal Pipe Containing Trapped Air. Journal of Hydraulic Engineering, 128(6), 625-634. doi:10.1061/(asce)0733-9429(2002)128:6(625)Cabrera, E., Abreu, J., Pérez, R., & Vela, A. (1992). Influence of Liquid Length Variation in Hydraulic Transients. Journal of Hydraulic Engineering, 118(12), 1639-1650. doi:10.1061/(asce)0733-9429(1992)118:12(1639

Exact skeletonization method in water distribution systems for hydraulic and quality models

[EN] A mathematical model is a powerful tool for simulating different scenarios that occur in a water distribution network without making physical experimentation. According to the objectives, a model can be classified into three categories: layout, design and operation. Furthermore, the level of detail is strongly related to the objective that the model tries to achieve. However, bigger amount of information does not mean better accuracy. For example, a fully detailed mathematical model of the network would lead to know every single connection. Usually, this information is so difficult to compile as imprecise. Therefore, one of the most important stages in elaborating a model consists of the model simplification, also known as skeletonization. During the works made for model skeletonization some assumptions are made. Most of the times, these assumptions may produce significant errors. Among the different techniques for network skeletonization, series pipe removal is one of the most used. It consists of replacing several adjacent pipes with a single one which must present the same head losses than the pipes being substituted. When there are no intermediate consumptions the problem has been effectively solved. The problem arises when a demand appears in one of the pipes being removed. It has been demonstrated that methods which assume constant roughness coefficients (either Hazen-Williams or Darcy equations) produce errors in the head losses. These errors may be even higher if travel time is included as a restriction, for example in water quality models. This paper reviews the most common techniques for serial pipes association. The error will be evaluated in both hydraulic and quality models. Finally, a method for exact substitution of serial pipes with intermediate demands is proposed. This method imposes two restrictions (head losses and travel time) and gives exact results when the flow direction is known. The method is tested with an example that highlights the results.This work was supported by the projects “OPERAGUA”, (Project DPI2009-13674, Spain) and by the Program Initiation into research (Project 11140128) of the Comisión Nacional de Invest. Científica y Tecnológica, Chile.Martínez-Solano, FJ.; Iglesias Rey, PL.; Mora Meliá, D.; Fuertes-Miquel, VS. (2017). Exact skeletonization method in water distribution systems for hydraulic and quality models. Procedia Engineering. 186:286-293. https://doi.org/10.1016/j.proeng.2017.03.246S28629318

Transient phenomena during the emptying process of a single pipe with water air interaction

[EN] Emptying pipelines can be critical in many water distribution networks because subatmospheric pressure troughs could cause considerable damage to the system due to the expansion of entrapped air. Researchers have given relatively little attention to emptying processes compared to filling processes. The intricacy of computations of this phenomenon makes it difficult to predict the behaviour during emptying, and there are only a few reliable models in the literature. In this work, a computational model for simulating the transient phenomena in single pipes is proposed, and was validated using experimental results. The proposed model is based on a rigid column to analyse water movement, the air¿water interface, and air pocket equations. Two practical cases were used to validate the model: (1) a single pipe with the upstream end closed, and (2) a single pipe with an air valve installed on the upstream end. The results show how the model accurately predicts the experimental data, including the pressure oscillation patterns and subatmospheric pressure troughs.This study was supported by the Program Fondecyt Regular [Project 1180660] of the Comision Nacional de Investigacion Cientifica y Tecnologica (Conicyt), Chile, http://data.crossref.org/fundingdata/funder/10.13039/501100002848.Fuertes-Miquel, VS.; Coronado-Hernández, OE.; Iglesias Rey, PL.; Mora Melia, D. (2019). Transient phenomena during the emptying process of a single pipe with water air interaction. Journal of Hydraulic Research. 57(3):318-326. https://doi.org/10.1080/00221686.2018.1492465S318326573Bashiri-Atrabi, H., & Hosoda, T. (2015). The motion of entrapped air cavities in inclined ducts. Journal of Hydraulic Research, 53(6), 814-819. doi:10.1080/00221686.2015.1060272Cabrera, E., Abreu, J., Pérez, R., & Vela, A. (1992). Influence of Liquid Length Variation in Hydraulic Transients. Journal of Hydraulic Engineering, 118(12), 1639-1650. doi:10.1061/(asce)0733-9429(1992)118:12(1639)Coronado-Hernández, O. E., Fuertes-Miquel, V. S., Iglesias-Rey, P. L., & Martínez-Solano, F. J. (2018). Rigid Water Column Model for Simulating the Emptying Process in a Pipeline Using Pressurized Air. Journal of Hydraulic Engineering, 144(4), 06018004. doi:10.1061/(asce)hy.1943-7900.0001446Fuertes-Miquel, V. S., López-Jiménez, P. A., Martínez-Solano, F. J., & López-Patiño, G. (2016). Numerical modelling of pipelines with air pockets and air valves. Canadian Journal of Civil Engineering, 43(12), 1052-1061. doi:10.1139/cjce-2016-0209Guinot, V. (2001). The discontinuous profile method for simulating two-phase flow in pipes using the single component approximation. International Journal for Numerical Methods in Fluids, 37(3), 341-359. doi:10.1002/fld.177Hou, Q., Tijsseling, A. S., Laanearu, J., Annus, I., Koppel, T., Bergant, A., … van ’t Westende, J. M. C. (2014). Experimental Investigation on Rapid Filling of a Large-Scale Pipeline. Journal of Hydraulic Engineering, 140(11), 04014053. doi:10.1061/(asce)hy.1943-7900.0000914Izquierdo, J., Fuertes, V. S., Cabrera, E., Iglesias, P. L., & Garcia-Serra, J. (1999). Pipeline start-up with entrapped air. Journal of Hydraulic Research, 37(5), 579-590. doi:10.1080/00221689909498518Laanearu, J., Annus, I., Koppel, T., Bergant, A., Vučković, S., Hou, Q., … van’t Westende, J. M. C. (2012). Emptying of Large-Scale Pipeline by Pressurized Air. Journal of Hydraulic Engineering, 138(12), 1090-1100. doi:10.1061/(asce)hy.1943-7900.0000631Leon, A. S., Ghidaoui, M. S., Schmidt, A. R., & Garcia, M. H. (2010). A robust two-equation model for transient-mixed flows. Journal of Hydraulic Research, 48(1), 44-56. doi:10.1080/00221680903565911Liou, C. P., & Hunt, W. A. (1996). Filling of Pipelines with Undulating Elevation Profiles. Journal of Hydraulic Engineering, 122(10), 534-539. doi:10.1061/(asce)0733-9429(1996)122:10(534)Liu, D., Zhou, L., Karney, B., Zhang, Q., & Ou, C. (2011). Rigid-plug elastic-water model for transient pipe flow with entrapped air pocket. Journal of Hydraulic Research, 49(6), 799-803. doi:10.1080/00221686.2011.621740Malekpour, A., & Karney, B. (2014). Column separation and rejoinder during rapid pipeline filling induced by a partial flow blockage. Journal of Hydraulic Research, 52(5), 693-704. doi:10.1080/00221686.2014.905502Martins, S. C., Ramos, H. M., & Almeida, A. B. (2015). Conceptual analogy for modelling entrapped air action in hydraulic systems. Journal of Hydraulic Research, 53(5), 678-686. doi:10.1080/00221686.2015.1077353Pozos, O., Gonzalez, C. A., Giesecke, J., Marx, W., & Rodal, E. A. (2010). Air entrapped in gravity pipeline systems. Journal of Hydraulic Research, 48(3), 338-347. doi:10.1080/00221686.2010.481839Tijsseling, A. S., Hou, Q., Bozkuş, Z., & Laanearu, J. (2015). Improved One-Dimensional Models for Rapid Emptying and Filling of Pipelines. Journal of Pressure Vessel Technology, 138(3). doi:10.1115/1.4031508Wang, K.-H., Shen, Q., & Zhang, B. (2003). Modeling propagation of pressure surges with the formation of an air pocket in pipelines. Computers & Fluids, 32(9), 1179-1194. doi:10.1016/s0045-7930(02)00103-2Wang, H., Zhou, L., Liu, D., Karney, B., Wang, P., Xia, L., … Xu, C. (2016). CFD Approach for Column Separation in Water Pipelines. Journal of Hydraulic Engineering, 142(10), 04016036. doi:10.1061/(asce)hy.1943-7900.0001171Zhou, L., & Liu, D. (2013). Experimental investigation of entrapped air pocket in a partially full water pipe. Journal of Hydraulic Research, 51(4), 469-474. doi:10.1080/00221686.2013.785985Zhou, L., Liu, D., & Karney, B. (2013). Investigation of Hydraulic Transients of Two Entrapped Air Pockets in a Water Pipeline. Journal of Hydraulic Engineering, 139(9), 949-959. doi:10.1061/(asce)hy.1943-7900.0000750Zhou, L., Liu, D., Karney, B., & Wang, P. (2013). Phenomenon of White Mist in Pipelines Rapidly Filling with Water with Entrapped Air Pockets. Journal of Hydraulic Engineering, 139(10), 1041-1051. doi:10.1061/(asce)hy.1943-7900.000076

The short and long-term effects of aerobic, strength, or mixed exercise programs on schizophrenia symptomatology

The purpose of this study was to compare the effects of three different physical exercise programs on the symptomatology, body composition, physical activity, physical fitness, and quality of life of individuals with schizophrenia. A total of 432 patients were assessed for eligibility and 86 were randomized into the aerobic (n = 28), strength (n = 29) or mixed (n = 29) groups. Positive, negative, and general symptoms of psychosis, body mass index (BMI), physical activity (IPAQ-SF), physical fitness (6-min walk test [6MWT] and hand-grip strength [HGS]), and quality of life (WHOQUOL-BREF) were assessed at baseline, post-intervention (16 weeks), and at 10-months. Our results at 16 weeks showed significant improvements in all three groups in the negative, general, and total symptoms with moderate to large effect sizes (P < 0.01, ¿p2 > 0.11), no change in the BMI, 6MWT or IPAQ-SF, and a significant improvement in the HGS test in the strength and mixed groups (P = 0.05, ¿p2 > 0.08). Nonetheless, all the improvements had disappeared at 10 months. We concluded that 3 weekly sessions of a moderate to vigorous progressive exercise program for 16 weeks improved the symptomatology of individuals with schizophrenia in all three groups, with no differences between them. However, the effects had declined to baseline levels by the 10-month follow-up, suggesting that exercise interventions should be maintained over time. © 2021, The Author(s)

Analysis of the technical documentation of the designs and projects of Leonardo da Vinci

[EN] Leonardo da Vinci improved and fully completed the drawings and sketches of the designs of the Italian engineers who were contemporaries or who preceded him. Thus, he improved the machine designs of Paolo Santini and Francesco di Giorgio Martini, or those of the hydraulic devices of Mariano di Iacopo. He also complemented and exceeded Brunelleschi's crane designs for his Arno River detour project, arriving to elaborate specifications and documents with similar characteristics to the current ones. As an example, in his project of the Sforza¿s Great Horse, he develops the memory, the general and detailed plans, the legends incorporated into the plans, etc., and in his project of the Mausoleum for Marshal Trivulcio he incorporates a budget with detailed prices by items, almost equivalent to those made today. The article aims to demonstrate the document superiority of Leonardo's designs in front of his contemporaries, showing that the documentation elaborated by him for some of his technical designs allow us to qualify him as a precursor of the modern technical documentation.[ES] Leonardo da Vinci mejoró y completó con creces los dibujos y esbozos de los diseños de los ingenieros italianos coetáneos o que le precedieron. Así, mejoró los diseños de máquinas de Paolo Santini y de Francesco di Giorgio Martini, o los de los artilugios hidráulicos de Mariano di Iacopo. Igualmente complementó y superó los diseños de grúas de Brunelleschi para su proyecto de desvío del Río Arno, llegando a elaborar especificaciones y documentos con características similares a las actuales. A modo de ejemplo, en su proyecto del Gran Caballo Sforza, desarrolla la memoria, los planos generales y de detalle, las leyendas incorporadas a los planos, etc., y en su proyecto del Mausoleo para el Mariscal Trivulcio incorpora un presupuesto con precios detallados por partidas, casi equivalente a los que se realizan hoy en día. El artículo quiere demostrar la superioridad documental de los diseños de Leonardo frente a sus coetáneos, mostrando que la documentación por él elaborada para algunos de sus diseños técnicos permiten calificarle como un precursor de la moderna documentación técnica.Cerveró Meliá, E.; Ferrer-Gisbert, P.; Capuz-Rizo, SF. (2019). Análisis de la documentación técnica de los diseños y proyectos de Leonardo da VInci. AEIPRO. 731-743. http://hdl.handle.net/10251/181235S73174

Sensor Data Visualisation: A Composition-Based Approach to Support Domain Variability

International audienceIn the context of the Internet of Things, sensors are surrounding our environment. These small pieces of electronics are inserted in everyday life's elements (e.g., cars, doors, radiators, smartphones) and continuously collect information about their environment. One of the biggest challenges is to support the development of accurate monitoring dashboard to visualise such data. The one-size-fits-all paradigm does not apply in this context, as user's roles are variable and impact the way data should be visualised: a building manager does not need to work on the same data as classical users. This paper presents an approach based on model composition techniques to support the development of such monitoring dashboards, taking into account the domain variability. This variability is supported at both implementation and modelling levels. The results are validated on a case study named SmartCampus, involving sensors deployed in a real academic campus

Compiling the actuarial balance for pay-as-you-go pension systems. Is it better to use the hidden asset or the contribution asset?

The aim of this article is twofold: to establish the connection between the 'Contribution Asset' (CA) and the 'Hidden Asset' (HA) and to determine whether using either of them to compile the Actuarial Balance (AB) sheet in the Pay-As-You-Go (PAYG) pension system will provide a reliable solvency indicator. With these aims in mind, we develop a model based on those first put forward by Settergren and Mikula (2005) and Boado-Penas et al. (2008) to obtain the analytical properties of the CA and to confirm its soundness as a measure of the assets of a PAYG scheme. Our model also enables us to explore whether, and to what extent, the HA can be considered a second alternative measure of the assets for PAYG schemes. The main theoretical finding is that, despite their very different natures, the HA and the CA may nearly coincide at the limit when the interest rate of the financial market approaches the growth of the covered wage bill from above, but the HA supplies a solvency indicator which is not always consistent with the system's financial health.</p

Psychosocial study about the consequences of work in hospital nurses as human resource management

OBJECTIVES: To analyze the relation between psychosocial and sociodemographic variables in nursing professionals. To discover the levels of job satisfaction, psychosomatic symptoms and psychological well-being in nurses. METHOD: The research was conducted in a sample of 476 nurses / as from nine hospitals in the region of Murcia (Spain). An occupational health protocol was distributed among the sample participants for completion, which contained tools for measuring and describing psychosocial and sociodemographic variables. RESULTS: Although there is no high risk for psychological problems among the sample participants, psychosomatic symptoms, job dissatisfaction, and low psychological wellbeing are present. CONCLUSIONS: The results contribute to research on the subject by identifying the presence of psychosocial disorders in nursing professionals, associated with job conditions and certain psychosocial and sociodemographic variables