Results 11 to 20 of about 58,381 (161)
Scientific Reports, 2021 Ritz eigenvalues only provide upper bounds for the energy levels, while obtaining lower bounds requires at least the calculation of the variances associated with these eigenvalues. The well-known Weinstein and Temple lower bounds based on the eigenvalues
Miklos Ronto +2 more
doaj +1 more source
Lower and Upper Bounds of Fractional Metric Dimension of Connected Networks
Fractal and Fractional, 2021 The distance centric parameter in the theory of networks called by metric dimension plays a vital role in encountering the distance-related problems for the monitoring of the large-scale networks in the various fields of chemistry and computer science ...
Muhammad Javaid +5 more
doaj +1 more source
Tail Bounds for the Wiener Index of Random Trees [PDF]
Discrete Mathematics & Theoretical Computer Science, 2007 Upper and lower bounds for the tail probabilities of the Wiener index of random binary search trees are given. For upper bounds the moment generating function of the vector of Wiener index and internal path length is estimated.
Tämur Ali Khan, Ralph Neininger
doaj +1 more source
Boundary Value Problems, 2020 In the paper, we investigate global and blow-up solutions for a class of nonlinear reaction diffusion equations with Robin boundary conditions. By using auxiliary functions and a first-order differential inequality technique, we establish conditions on ...
Huimin Tian, Lingling Zhang
doaj +1 more source
Upper and lower bounds for $F_v(4,4;5)$ [PDF]
The Electronic Journal of Combinatorics, 2010 In this note we give a computer assisted proof showing that the unique $(5,3)$-Ramsey graph is the unique $K_5$-free graph of order 13 giving $F_v(3,4;5) \leq 13$, then we prove that $17 \leq F_v(2,2,2, 4; 5) \leq F_v(4, 4; 5) \leq 23$. This improves the previous best bounds $16 \leq F_v(4, 4; 5) \leq 25$ provided by Nenov and Kolev.
Xu, Xiaodong, Luo, Haipeng, Shao, Zehui
openaire +2 more sources
Improving bounds on packing densities of 4-point permutations [PDF]
Discrete Mathematics & Theoretical Computer Science, 2018 We consolidate what is currently known about packing densities of 4-point permutations and in the process improve the lower bounds for the packing densities of 1324 and 1342.
Jakub Sliacan, Walter Stromquist
doaj +1 more source
Lower and Upper Bounds for Nef Cones [PDF]
International Mathematics Research Notices, 2011 25 pages, 4 figures.
Gibney, Angela, Maclagan, Diane
openaire +2 more sources
Upper and lower bounds on gravitational entropy [PDF]
Journal of Cosmology and Astroparticle Physics, 2008 The gravitational entropy of the Universe is large and subtle to calculate. A lower bound is well known from supermassive black holes at the centers of galaxies, but the remainder is harder to pin down. A parametric model of clumped matter entropy is provided.
Frampton, Paul H., Kephart, Thomas W.
openaire +2 more sources
Method of intermediate problems in the theory of Gaussian quantum dots placed in a magnetic field
Condensed Matter Physics, 2006 Applicability of the method of intermediate problems to the investigation of the energy eigenvalues and eigenstates of a quantum dot (QD) formed by a Gaussian confining potential in the presence of an external magnetic field is discussed. Being smooth at
A.V.Soldatov +2 more
doaj +1 more source
Some lower and upper bounds on the third ABC index
AKCE International Journal of Graphs and Combinatorics, 2016 Atom-bond connectivity (ABC) index has been applied up to now to study the stability of alkanes and the strain energy of cycloalkanes. Graovac defined the second ABC index as ABC2(G)=∑vivj∈E(G)1ni+1nj−2ninj, and Kinkar studied the upper bounds.
Dae-Won Lee
doaj +1 more source