Results 11 to 20 of about 23,228 (258)
The Jordan curve theorem in the Khalimsky plane
Applied General Topology, 2008 The connectivity in Alexandroff topological spaces is equivalent to the path connectivity. This fact gets some specific properties to Z2, equipped with the Khalimsky topology.
Ezzeddine Bouassida
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A Note on the Geometry of Closed Loops
Mathematics, 2023 In this paper, we utilize the Ramsey theory to investigate the geometrical characteristics of closed contours. We begin by examining a set of six points arranged on a closed contour and connected as a complete graph. We assign the downward-pointing edges
Nir Shvalb +3 more
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A Crossing Lemma for Jordan curves
Advances in Mathematics, 2018 If two Jordan curves in the plane have precisely one point in common, and there they do not properly cross, then the common point is called a {\em touching point}. The main result of this paper is a Crossing Lemma for simple curves: Let $X$ and $T$ stand for the sets of intersection points and touching points, respectively, in a family of $n$ simple ...
Pach, János +2 more
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Discrete Jordan Curve Theorems
Journal of Combinatorial Theory, Series B, 1989 Short proofs of three graph theoretic versions of the Jordan Curve Theorem are given.
Department of Mathematics, University of Florida, Gainesville, Florida 32611 USA ( host institution ) +2 more
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One Health, 2021 The evolution of the COVID-19 pandemic in Jordan during the first 10 months of the epidemic was peculiar and can be easily categorized in three different phases: a first period featuring a very low number of reported cases, a second period with ...
Saverio Bellizzi +11 more
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A ternary relation for structuring the digital plane
ITM Web of Conferences, 2017 We discuss certain ternary relations, called plain, and show that each of them induces a connectedness on its underlying set. This connectedness allows for definitions of concepts of simple closed and Jordan curves.
Šlapal Josef
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A Proof of the Jordan Curve Theorem [PDF]
Bulletin of the London Mathematical Society, 1980 Let F be a Jordan curve in the plane, i.e. the image of the unit circle C = {(x,y);x + y = 1} under an injective continuous mapping y into R. The Jordan curve theorem [1] says that / ? 2 \ F is disconnected and consists of two components. (We shall use the original definition whereby two points are in the same component if and only if they can be ...
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On Disks Enclosed by Smooth Jordan Curves
Symmetry, 2023 Given a smooth-plane Jordan curve with bounded absolute curvature κ>0, we determine equivalence classes of distinctive disks of radius 1/κ included in both plane regions separated by the curve. The bound on absolute curvature leads to a completely symmetric trajectory behaviour with respect to the curve turning.
José Ayala-Hoffmann, Víctor Ayala
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Journal of Asthma and Allergy, 2023 Ebaa M Alzayadneh,1 Suzan A Al Bdour,1 Eman R Elayeh,2 Mai M Ababneh,3 Ruqaya A Al-ani,3 Alia Shatanawi,4 Montaha Al-Iede,3 Enas Al-Zayadneh3 1Department of Physiology and Biochemistry, School of Medicine, The University of Jordan, Amman, Jordan ...
Alzayadneh EM +7 more
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Journal of Primary Care & Community Health, 2021 Background One of the newly faced challenges during the COVID-19 is vaccine hesitancy (VH). The validated 5C scale, that assesses 5 psychological antecedents of vaccination, could be effective in exploring COVID-19 VH.
Ramy Mohamed Ghazy +6 more
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