Results 31 to 40 of about 387,211 (278)
BMC Biology, 2021 Background A major goal of evolutionary developmental biology is to discover general models and mechanisms that create the phenotypes of organisms. However, universal models of such fundamental growth and form are rare, presumably due to the limited ...
Alistair R. Evans +9 more
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Spiral-logarithmic structures in a Heisenberg ferromagnet [PDF]
Journal of Experimental and Theoretical Physics Letters, 2001 Spiral-logarithmic structure is suggested as a stationary solution of a modified equation for the Heisenberg model, and the single- and N-soliton solutions are constructed on this base.
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THE LOGARITHMIC SPIRAL AND ITS SPHERICAL COUNTERPART
Journal of Industrial Design and Engineering Graphics, 2020 Logarithmic spirals are isogonal trajectories of pencils of lines. From a series of geometric consequences, we pick out a few which are relevant for kinematics: When a logarithmic spiral rolls on a line, its asymptotic point traces a straight line. Hence,
Hellmuth Stachel +2 more
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Well-posedness of logarithmic spiral vortex sheets [PDF]
, 2023 We consider a family of 2D logarithmic spiral vortex sheets which include the celebrated spirals introduced by Prandtl (Vortr\"age aus dem Gebiete der Hydro- und Aero-dynamik, 1922) and by Alexander (Phys. Fluids, 1971).
Cieślak, T. +2 more
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A geometric approach to inelastic collapse
Journal of Computational Geometry, 2022 We show in this note how to interpret logarithmic spiral tilings as one-dimensional particle systems undergoing inelastic collapse. By deforming the spirals appropriately, we can simulate collisions among particles with distinct or varying coefficients ...
Yufei Zheng +2 more
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The Elliptic Logarithmic Spiral—a New Curve [PDF]
Nature, 1922 IF, in an elastic system with one degree of freedom, and friction proportional to the velocity, the relation of the “free” force to the displacement be considered, an interesting curve results.
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Universe, 2021 Double-spiral galaxies are common in the Universe. It is known that the logarithmic double spiral is a Maximum Entropy geometry in hyperbolic (flat) spacetime that well represents an idealised spiral galaxy, with its central supermassive black hole (SMBH)
Michael C. Parker, Chris Jeynes
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Influence of Vane Structure on Flow Field in Turbo-air Classifier
Shiyou jixie, 2021 Turbo-air classifiers have low classifying precision and efficiency, which are mainly resulted from its internal structure. In this study, based on the air flow trajectory equation, three structural types of guide vanes are designed including straight ...
Yu Dankui +6 more
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Inverse Stereographic Projection of the Logarithmic Spiral
, 2016 Educação Superior::Ciências Exatas e da Terra::MatemáticaThis Demonstration shows the inverse stereographic projection of a logarithmic spiral onto the unit sphere.
Mahieu, Erik
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Acoustic Imaging-Based UAV Sound Source Separation Technology [PDF]
E3S Web of ConferencesTo address the key technical challenge of accurately separating and localizing noise sources from the propellers of quadrotor UAVs, this paper innovatively proposes an acoustic imaging method based on a 64-channel multi-arm logarithmic spiral array ...
Wang Lingzhi, He Tianlun, Chen Da
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