Results 31 to 40 of about 1,605,869 (375)
Enhanced photovoltage for inverted planar heterojunction perovskite solar cells
Science, 2018 Perovskite layers make the grade Inverted planar perovskite solar cells offer opportunities for a simplified device structure compared with conventional mesoporous titanium oxide interlayers.
Deying Luo +23 more
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Clustered Planarity = Flat Clustered Planarity [PDF]
, 2018 The complexity of deciding whether a clustered graph admits a clustered planar drawing is a long-standing open problem in the graph drawing research area. Several research efforts focus on a restricted version of this problem where the hierarchy of the clusters is "flat", i.e., no cluster different from the root contains other clusters.
Maurizio Patrignani +1 more
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Every Planar Map Is Four Colorable
Mathematical Solitaires & Games, 2019 As has become standard, the four color map problem will be considered in the dual sense as the problem of whether the vertices of every planar graph (without loops) can be colored with at most four colors in such a way that no pair of vertices which lie ...
K. Appel, W. Haken
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Abelian Equations and Rank Problems for Planar Webs [PDF]
, 2006 We find an invariant characterization of planar webs of maximum rank. For 4-webs, we prove that a planar 4-web is of maximum rank three if and only if it is linearizable and its curvature vanishes. This result leads to the direct web-theoretical proof of
Goldberg, Vladislav V. +1 more
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Journal of Graph Algorithms and Applications, 2018 In this paper, we introduce and study multilevel planarity, a generalization of upward planarity and level planarity. Let $G = (V, E)$ be a directed graph and let $\ell: V \to \mathcal P(\mathbb Z)$ be a function that assigns a finite set of integers to each vertex.
Barth, Lukas +3 more
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IEEE Microwave Magazine, 2006 The development of the broadband antenna for ultrawideband (UWB) applications such as communications, imaging, radar, and localization is discussed. UWB systems are based on transmitting and receiving impulses with extremely wide spectra. As the antennas for UWB should have broad operating bandwidths for impedance matching and high-gain radiation in ...
Cheng, Zhi Ning +5 more
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Italian National Conference on Sensors, 2021 Recent developments in the field of microwave planar sensors have led to a renewed interest in industrial, chemical, biological and medical applications that are capable of performing real-time and non-invasive measurement of material properties.
R. Alahnomi +6 more
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Communications in Mathematical Physics, 1978 The authors describe their method for counting planar Feynman diagrams of quantum field theory. Mathematicians who are not familiar with the current jargon of quantum field theory are likely to find this paper rather difficult to follow. In order to demonstrate the usefulness of their method, the authors calculate the ground state energy of a system of
Brézin, E. +3 more
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Circularly Polarized Broadband Printed Antenna for Wireless Applications
Sensors, 2018 A simple, compact sickle-shaped printed antenna with a slotted ground plane is designed and developed for broadband circularly polarized (CP) radiation.
Md. Samsuzzaman, Mohammad Tariqul Islam
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Structural properties of 1-planar graphs and an application to acyclic edge coloring [PDF]
, 2010 A graph is called 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, we establish a local property of 1-planar graphs which describes the structure in the neighborhood of small vertices (i.e ...
Liu, Guizhen, Wu, Jian-Liang, Zhang, Xin
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