scholarly journals Optimal Local Routing on Delaunay Triangulations Defined by Empty Equilateral Triangles

2015 ◽  
Vol 44 (6) ◽  
pp. 1626-1649 ◽  
Author(s):  
Prosenjit Bose ◽  
Rolf Fagerberg ◽  
André van Renssen ◽  
Sander Verdonschot
Keyword(s):  
Delaunay Triangulations ◽  
Equilateral Triangles ◽  
Local Routing

scholarly journals BioFilm©

2000 ◽  
Vol 8 (2) ◽  
pp. 6-7
Author(s):  
Lee van Hook
Keyword(s):  
Recent Article ◽  
Metal Halide ◽  
Toxic Effects ◽  
Polymer Science ◽  
Complex Combination ◽  
Dry Biomass ◽  
Equilateral Triangles ◽  
Silver Grains

Photographic chemistry has long been a complex combination of inorganic metal-halide and organic chemistries and polymer science. We at the P.R.I, have managed to add biology to this stew.Silver has long been known as a toxicelement to microbes, and so used as a drug to kill bacteria. But there are bacteria that can survive in environments high in silver. It has been reported that some bacteria can accumulate up to 25% of their dry biomass as silver, and so acquire resistance to the toxic effects of silver. Also, a recent article in the Proc. Nat. Acad.Sci. describes the intracellular deposition of silver grains in such shapes as hexagons and equilateral triangles.

Acute PEBI Grid Generation for Reservoir Geometries

2021 ◽  
Author(s):  
Shahid Manzooor ◽  
Michael G. Edwards ◽  
Ali H. Dogru
Keyword(s):  
Unstructured Grid ◽  
Control Volume ◽  
Control Point ◽  
Vertical Direction ◽  
Grid Generation ◽  
Geometric Constraints ◽  
Reconstruction Technique ◽  
Delaunay Triangulations ◽  
Flux Approximation ◽  
Mesh Reconstruction

Abstract An unstructured grid generation method is presented that automates control-volume boundary alignment to geological objects and control point alignment to complex wells. The grid generation method is coupled with an iterative acute mesh reconstruction technique, to construct essentially acute triangulations, while satisfying quite general geometric constraints. For well aligned grids control points are constrained to the well trajectory and protection circles are used, whereas for boundary aligned grids halo construction is performed. Unstructured Delaunay triangulations (DT) have the desirable locally orthogonal perpendicular bisectional (PEBI) property, required by the industry standard two-point flux approximation for consistency for isotropic fields. The PEBI property can only be exploited if such grids are comprised of acute simplexes, with circumcentres located inside their respective elements. The method presented enables acute DT layered mesh generation while honoring internal boundaries and wells in a two dimensional space. A dual (Voronoi) grid derived from a feature honored simplicial mesh is then projected in the vertical direction generating 2.5D PEBI grids. Effectiveness of the method to construct acute PEBI grids honoring geological objects and complex wells is demonstrated by meshing representative reservoir geometries. Numerical results are presented that verify consistency of the two-point flux on the resulting boundary-aligned acute PEBI grids. Development of an unstructured grid generation method which 1) Automates interior boundary alignment, 2) Honors features with respect to control point and/or control volume, and 3) Generates acute PEBI grids for reservoir geometries is presented. A unique workflow is presented to generate boundary aligned acute PEBI grids for complex geometries. Development of boundary aligned grids that honor both geological objects and multilateral complex wells, together with mesh reconstruction to ensure circumcenter containment is presented. Further, 3D PEBI grid generation method which can limit refinement to well perforations and geological objects is also described.

scholarly journals Sustainable Geometric and Bio-Cultural/Cultural Models of Human Society: The Role of Non-Capitalist Cooperation in Times of Civilizational/Environmental Crisis

2017 ◽  
Vol 10 (2) ◽  
pp. 13
Author(s):  
M. S. Sthel ◽  
J. G. R. Tostes ◽  
J. R. Tavares
Keyword(s):  
Carbon Footprint ◽  
Cultural Models ◽  
Total Carbon ◽  
Environmental Crisis ◽  
Human Society ◽  
Capitalist System ◽  
Equilateral Triangles ◽  
Footprint Area ◽  
The Individual

The Sustainable Complex Triangular Cells (SCTC) and bio-cultural/cultural models of human society are employed here. Regarding SCTC model, the cell areas represent the individual´s carbon footprint. Scalene triangles represent each individual in the present competitive standard (inward arrows). Equilateral triangles (outward arrows) are “summed” so as forming cooperative-hexagonal bodies leading to a collaborative model of society, reducing the total carbon footprint area as regard the formal analogous sum of each individual (inward) non-cooperative triangle. We particularly have focused on environmental global limits of the capitalist system, with SCTC modeling an accelerated global anti-ecological “scalenization” process from the 29 crisis to the present neoliberal stage of capitalism. Employing again the SCTC model, we describe and exemplify instable and short lifetime “islands” built up through evanescent local process of “cooperative equilateralization” (outward arrows) in the last 40 years. Such non-capitalist features were “mixed in” with competitive “scalenized” features of the capitalist “ocean”. In the final topic, we will consider bio-cultural (Nowak and Wilson) models of the human history and a cultural (Weber-Alberoni) model for great inflexions in the western history. All these models intersect via human cooperation. Particularly, that last model is complementary to the above small and instable “islands” sketch: but now we deal with western religious and secular, non- capitalist, purely cooperative experiences, which correspond to the above labeled SCTC “cooperative equilateralization”. Such weber-alberonian “islands” may be – some few times - sufficiently stable for rapid and great expansions leading, e.g., to a “civilizational/environmental jump” in the presently menaced planet.

Sign in / Sign up

Export Citation Format

Share Document