We prove an upper bound on the sum of distances between eigenvalues a perturbed Schrödinger operator H0 − V and lowest eigenvalue H0. Our results hold for operators = −Δ V0 in one dimension with single-well potentials. rely variation well-known commutation method. In Pöschl–Teller Coulomb cases, we are able to use explicit factorizations establish improved bounds.

For any pseudo-Anosov automorphism on an orientable closed surface, inequality is established by bounding certain growth of virtual homological eigenvalues with the Weil-Petersson translation length. The new fits nicely other known inequalities due to Kojima and McShane (2018) Lê (2014). quantity be considered square sum logarithmic radii (with multiplicity) outside complex unit circle, called ...

for a simple digraph $g$ of order $n$ with vertex set${v_1,v_2,ldots, v_n}$, let $d_i^+$ and $d_i^-$ denote theout-degree and in-degree of a vertex $v_i$ in $g$, respectively. let$d^+(g)=diag(d_1^+,d_2^+,ldots,d_n^+)$ and$d^-(g)=diag(d_1^-,d_2^-,ldots,d_n^-)$. in this paper we introduce$widetilde{sl}(g)=widetilde{d}(g)-s(g)$ to be a new kind of skewlaplacian matrix of $g$, where $widetilde{d}(g...

let $d$ be a digraph with skew-adjacency matrix $s(d)$. then the skew energyof $d$ is defined to be the sum of the norms of all eigenvalues of $s(d)$. denote by$mathcal{o}_n$ the class of digraphs on order $n$ with no even cycles, and by$mathcal{o}_{n,m}$ the class of digraphs in $mathcal{o}_n$ with $m$ arcs.in this paper, we first give the minimal skew energy digraphs in$mathcal{o}_n$ and $mat...

The paper presents a mathematical base modeling combined to Modified-Winding -Function-Approach (MWFA) for eccentricity fault detection of a round-rotor synchronous machine. For this aim, a 6-pole machine is considered, and the machine inductances are computed by MWFA in healthy and also under eccentricity fault. A numerical discrete-time method has been proposed to machine modeling in voltage-...

Direct displacement based design (DDBD) is a conceptual framework that directly design a structure to achieve an expected performance level under specified seismic intensity. In this study, two important issues relevant to torsional response of mass eccentric 8-story RC building designed with DDBD approach are investigated. These issues are including the effects of unbalanced mass distribution ...

the eccentricity connectivity index of a molecular graph g is defined as (g) = av(g)deg(a)ε(a), where ε(a) is defined as the length of a maximal path connecting a to othervertices of g and deg(a) is degree of vertex a. here, we compute this topological index forsome infinite classes of dendrimer graphs.

Usually, principal components analysis is carried out by calculating the eigenvalues and eigenvectors of the correlation matrix. With N cases and P variables, if we write X for the N × P matrix which has been standardised so that columns have zero mean and unit standard deviation, we find the eigenvalues and eigenvectors of the P × P matrix X.X (which is N or (N − 1) times the correlation matri...