1,356,041 research outputs found
<i>Nemesignis</i>, a Replacement Name for <i>Nemesis</i> Furfaro & Mariottini, 2021 (Mollusca, Gastropoda, Myrrhinidae), Preoccupied by <i>Nemesis</i> Risso, 1826 (Crustacea, Copepoda)
No full textThe genus Nemesis Furfaro & Mariottini, 2021, was recently introduced for an independent lineage of aeolid nudibranchs, and Dondice banyulensis Portmann & Sandmeier, 1960, established as its type species. Anyway, the presence of a senior homonym, Nemesis Risso, 1826, was evidently missed. In fact, in 1826, Risso established this genus for a group of Copepoda (Arthropoda, Crustacea) and according to the Principle of Priority (ICZN) only the senior homonym may be used as a valid name. Therefore, a new replacement name is here proposed. Furthermore, the genus name Nanuca Er. Marcus, 1957, has priority over Dondice Er. Marcus, 1958 and consequently, the species in this clade should be classified under Nanuca, mostly as new combinations
Ecology and distribution of the Mediterranean Dondice trainitoi Furfaro and Mariottini, 2020 (Mollusca: Nudibranchia)
No full textDuring scientific technical dives in a marine animal forest (MAF) environment, the nudibranch Dondice trainitoi Furfaro & Mariottini 2020 was recorded on a rocky bottom at 50 m depth in the Salento Peninsula, Southern Italy, Eastern Mediterranean Sea. Further in situ explorations and broad bibliographic research within both the scientific and grey literature revealed that D. trainitoi is widely distributed across the Mediterranean Sea, despite what was previously known. Herein are the first records for the Adriatic Sea and the Apulia region of Italy, together with the deepest record of this species. An analysis of collected samples and both in situ and laboratory photographs of the hydrozoan colonies associated with D. trainitoi revealed its ecology and trophic behaviour; we conclude that the hydrozoan Obelia bidentata Clark, 1875 is its preferred prey, but that it also feeds on the athecate hydroid Eudendrium glomeratum Picard, 1952. These findings shed some light on the little-known ecology and distribution, on both a geographical and a bathymetric scale, of this species, which are fundamental to increasing knowledge on Mediterranean biodiversity and its ecosystem functions
Other institutionalization and everyday life : analytical possibilities from a pragmatic conception
No full textFil: Furfaro, Cristian. Universidad Nacional de La Plata; Argentin
As cabeças indígenas de Franco Furfaro
No full textFour sculptural heads by the artist Franco Furfaro are on display in the upper rotunda of the Museo de La Plata. These pieces share the space with ten other similar works sculpted by Ernesto Soto Avendaño, which at first glance would seem to all belong to the same author. However, a closer look allows distinquishing between them and even finding interesting differences, when we delve deeper into the knowledge of this heritage. This work, despite the scarcity of data and sources of information, focuses on the history of how these sculptures were acquired, the institutional goals of the museum when purchasing them and the possible motivations that led the artist to make them.En la rotonda superior del Museo de La Plata se exponen cuatro cabezas escultóricas del artista Franco Furfaro. Las piezas comparten el espacio con otras diez obras similares, las esculturas de Ernesto Soto Avendaño, que en una vista general parecen pertenecer todas a un mismo autor. Sin embargo, una mirada más aguda permite distinguirlas y aún encontrar interesantes diferencias cuando se profundiza en el conocimiento sobre este patrimonio. Este trabajo, a pesar de contar con escasos datos y fuentes de información, se detiene en la historia de la adquisición de la esculturas, los objetivos institucionales del museo al comprarlas y las posibles motivaciones que llevaron al artista a realizarlas.Na rotunda superior do Museu de La Plata estão expostas quatro cabeças escultóricas do artista Franco Furfaro. As peças compartilham o espaço com outras dez obras semelhantes, as esculturas de Ernesto Soto Avendaño, que numa visão geral parecem pertencer todas ao mesmo autor. No entanto, um olhar mais atento permite distingui-las e até encontrar diferenças interessantes quando se aprofunda no conhecimento deste patrimônio. Este trabalho, apesar de contar com poucos dados e fontes de informação, centra-se na história da aquisição das esculturas, nos objetivos institucionais do museu ao adquiri-las e nas possíveis motivações que levaram o artista a realizá-las
The indigenous heads by Franco Furfaro
No full textEn la rotonda superior del Museo de La Plata se exponen cuatro cabezas escultóricas del artista Franco Furfaro. Las piezas comparten el espacio con otras diez obras similares, las esculturas de Ernesto Soto Avendaño, que en una vista general parecen pertenecer todas a un mismo autor. Sin embargo, una mirada más aguda permite distinguirlas y aún encontrar interesantes diferencias cuando se profundiza en el conocimiento sobre este patrimonio. Este trabajo, a pesar de contar con escasos datos y fuentes de información, se detiene en la historia de la adquisición de la esculturas, los objetivos institucionales del museo al comprarlas y las posibles motivaciones que llevaron al artista a realizarlas.Four sculptural heads by the artist Franco Furfaro are on display in the upper rotunda of the Museo de La Plata. These pieces share the space with ten other similar works sculpted by Ernesto Soto Avendaño, which at first glance would seem to all belong to the same author. However, a closer look allows distinquishing between them and even finding interesting differences, when we delve deeper into the knowledge of this heritage. This work, despite the scarcity of data and sources of information, focuses on the history of how these sculptures were acquired, the institutional goals of the museum when purchasing them and the possible motivations that led the artist to make them.Facultad de Ciencias Naturales y Muse
¿As the ethnographer writes?: A look towards Bourgois's methodology from the idea of ethnographic authority
No full textEl objetivo del presente artículo es analizar la propuesta metodológica que Philippe Bourgois desarrolla en su obra En busca de respeto. Vendiendo crack en Harlem. Para ello, revisaremos la forma en que construye sus categorías teóricas y la estructura del libro, a partir de las observaciones realizadas y de las experiencias y opiniones de los habitantes de East Harlem. En este recorrido, repasaremos las perspectivas teóricas que el autor pone en juego, como así también los elementos que utiliza en la construcción de los relatos. Finalmente, reflexionaremos sobre la idea de autoridad etnográfica presente en el trabajo del antropólogo norteamericano.The objective of this article is to analyze the methodological proposal that Philippe Bourgois presents in his book In search of respect. Selling crack in El Barrio, reflecting on the way in which builds its conceptual categories and the structure of the book, based on the observations made and the experiences and opinions of the people of East Harlem. On this tour, we will review the theoretical perspectives that the author puts into play, as well as the items that he uses in the construction of the stories, to finally reflect on the idea of authority ethnographic present in the work of the American anthropologist.Fil: Furfaro, Cristian. Instituto de de Cultura Jurídica, Facultad de Ciencias Jurídicas y Sociales, Universidad Nacional de La Plata, CONICET
Learning Fuel-Optimal Trajectories for Space Applications via Pontryagin Neural Networks
No full textThis paper demonstrates the utilization of Pontryagin Neural Networks (PoNNs) to acquire control strategies for achieving fuel-optimal trajectories. PoNNs, a subtype of Physics-Informed Neural Networks (PINNs), are tailored for solving optimal control problems through indirect methods. Specifically, PoNNs learn to solve the Two-Point Boundary Value Problem derived from the application of the Pontryagin Minimum Principle to the problem’s Hamiltonian. Within PoNNs, the Extreme Theory of Functional Connections (X-TFC) is leveraged to approximate states and costates using constrained expressions (CEs). These CEs comprise a free function, modeled by a shallow neural network trained via Extreme Learning Machine, and a functional component that consistently satisfies boundary conditions analytically. Addressing discontinuous control, a smoothing technique is employed, substituting the sign function with a hyperbolic tangent function and implementing a continuation procedure on the smoothing parameter. The proposed methodology is applied to scenarios involving fuel-optimal Earth−Mars interplanetary transfers and Mars landing trajectories. Remarkably, PoNNs exhibit convergence to solutions even with randomly initialized parameters, determining the number and timing of control switches without prior information. Additionally, an analytical approximation of the solution allows for optimal control computation at unencountered points during training. Comparative analysis reveals the efficacy of the proposed approach, which rivals state-of-the-art methods such as the shooting technique and the adaptive Gaussian quadrature collocation method
Derecho a la resistencia en la Filosofía práctica contemporánea
No full textResumen temporalmente no disponible. La presente obra no cuenta con resumen provisto por el autor.Fil: Furfaro, María Alejandra. Universidad de Buenos Aires. Facultad de Filosofía y Letras
Derecho a la resistencia en la Filosofía práctica contemporánea
No full textResumen temporalmente no disponible. La presente obra no cuenta con resumen provisto por el autor.Fil: Furfaro, María Alejandra. Universidad de Buenos Aires. Facultad de Filosofía y Letras
Analysis and Performance Evaluation of ZEM/ZEV Guidance and Its Sliding Robustification for Autonomous Rendezvous in Relative Motion
No full textDevising closed-loop guidance algorithms for autonomous relative motion is an important problem within the field of orbital dynamics. However, very few closed-loop algorithms have been devised that can autonomously generate feedback trajectories to execute rendezvous in relative motion (e.g. Lopez and McInnes, 1995, JGCD). In this paper, we explore the application of the generalized Zero-Effort-Miss/Zero-Effort-Velocity (ZEM/ZEV) feedback guidance (Guo et al., 2013, JGCD) and its robustified version known as Optimal Sliding Guidance (OSG, Wibben and Furfaro, 2016, ASR) to the problem of closed-loop spacecraft rendezvous guidance. The ZEM/ZEV feedback guidance has been studied extensively and can be found in the literature for intercept, rendezvous, terminal guidance and landing applications. Such analytical closed-loop guidance has been originally conceived by Battin who devised an energy optimal, feedback acceleration command for powered planetary descent. Ebrahimi et al. (2008, AA) introduced the ZEV concept, as a partner for the well-known ZEM and integrated it with a sliding surface for missile guidance with fixed-time propulsive maneuvers. Furfaro et al. (2011, Advances in Astronautical Sciences) extended the idea to the problem of lunar landing guidance and set the basis for the theoretical development of a robust closed-loop algorithm for precision landing. ZEM/ZEM feedback guidance is attractive because of its analytical simplicity as well as potential for quasi-optimal fuel performance. When robustified by a time-dependent sliding term, the resulting OSG can be proven to be Globally Finite-Time Stable (GFTS) in spite of perturbation with known upper bound. Here, we study the guided relative motion of two spacecraft for which one of them is executing an autonomous rendezvous via the ZEM/ZEV feedback guidance and its robustifed OSG counterpart. When augmented via time-dependent sliding, the application of Lyapunov stability theory for non-autonomous systems provides the sufficient conditions for GFTS. Indeed, the OSG can be demonstrated to be GFTS for any linear and non-linear relative motion model (e.g. rendezvous in circular orbit or in highly eccentric orbit). Starting from the classical Clohessy-Wiltshire (CW) model, we systematically analyze the ability of the ZEM/ZEV feedback guidance to execute quasi-optimal closed-loop maneuvers and its ability to correct disturbances for precision guidance. Comparison with the OSG counterpart will provide an assessment of the need for robustification as function of different rendezvous conditions (e.g. rendezvous in highly elliptical orbit) and different thrusting constraints (e.g. limited thrust)
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