How not to characterize planar-emulable graphs
نویسندگان
چکیده
منابع مشابه
How Not to Characterize Planar-Emulable Graphs
We investigate the question of which graphs have planar emulators (a locally-surjective homomorphism from some finite planar graph)—a problem raised already in Fellows’ thesis (1985) and conceptually related to the better known planar cover conjecture by Negami (1986). For over two decades, the planar emulator problem lived poorly in a shadow of Negami’s conjecture—which is still open—as the tw...
متن کاملIntroduction to Planar Graphs
The topic of planar graphs is covered in many books and articles, but the treatment usually relies on intuition or on deep topological theorems that are quoted without proof. I give a self-contained rigorous introduction to planar graphs. 1 The Jordan curve theorem and Euler’s formula Throughout these notes graphs are allowed to have loops and multiple edges. Definition 1.1. A polygonal arc is ...
متن کاملMechanical properties of How to characterize differen
Face deformations during speech in different styles are observed by measuring movements of 65 markers glued on the subject's face including the lips. A factor analysis decomposes lower lip movements generated by jaw gestures and those by intrinsic lip gestures. We then characterize mechanical properties of these movements in terms of global variables calculated over an utterance as the total mo...
متن کاملPlanar Graphs as VPG-Graphs
A graph is Bk-VPG when it has an intersection representation by paths in a rectangular grid with at most k bends (turns). It is known that all planar graphs are B3-VPG and this was conjectured to be tight. We disprove this conjecture by showing that all planar graphs are B2-VPG. We also show that the 4-connected planar graphs constitute a subclass of the intersection graphs of Z-shapes (i.e., a...
متن کاملConvex drawings of hierarchical planar graphs and clustered planar graphs
Hierarchical graphs are graphs with layering structures; clustered graphs are graphs with recursive clustering structures. Both have applications in VLSI design, CASE tools, software visualisation and visualisation of social networks and biological networks. Straight-line drawing algorithms for hierarchical graphs and clustered graphs have been presented in [P. Eades, Q. Feng, X. Lin and H. Nag...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Advances in Applied Mathematics
سال: 2013
ISSN: 0196-8858
DOI: 10.1016/j.aam.2012.06.004