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Related papers: On the Irregularity of Some Molecular Structures

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Let G be an n-vertex graph with m edges. The degree deviation measure of G is defined as s(G)=sum v in V(G)|degG(v)-(2m/n)|, where n and m are the number of vertices and edges of G, respectively. The aim of this paper is to prove the…

Combinatorics · Mathematics 2020-02-24 Ali Ghalavand , Ali Reza Ashrafi

The total $\sigma$-irregularity is given by $ \sigma_t(G) = \sum_{\{u,v\} \subseteq V(G)} \left(d_G(u) - d_G(v)\right)^2, $ where $d_G(z)$ indicates the degree of a vertex $z$ within the graph $G$. It is known that the graphs maximizing…

Combinatorics · Mathematics 2024-11-05 Martin Knor , Riste Škrekovski , Slobodan Filipovski , Darko Dimitrov

Local Irregularity Conjecture states that every simple connected graph, except special cacti, can be decomposed into at most three locally irregular graphs, i.e., graphs in which adjacent vertices have different degrees. The connected…

Combinatorics · Mathematics 2025-02-13 Igor Grzelec , Alfréd Onderko , Mariusz Woźniak

Topological relations between three degree-based invariants of a connected graph G are investigated. We present novel inequalities including M1(G), M2(G) and F(G), and show that in all cases equality holds if G is a regular or a semiregular…

Combinatorics · Mathematics 2015-09-29 Tamás Réti , Imre Felde

There is powerful relation between the chemical behaviour of chemical compounds and their molecular structures. Topological indices defined on these chemical molecular structures are capable to predict physical properties, chemical…

Combinatorics · Mathematics 2018-05-15 Sourav Mondal , Nilanjan De , Anita Pal

The Fibonacci index of a graph is the number of its stable sets. This parameter is widely studied and has applications in chemical graph theory. In this paper, we establish tight upper bounds for the Fibonacci index in terms of the…

Discrete Mathematics · Computer Science 2024-03-11 Véronique Bruyère , Hadrien Mélot

Judging the significance and reproducibility of quantitative research requires a good understanding of relevant uncertainties, but it is often unclear how well these have been evaluated and what they imply. Reported scientific uncertainties…

Applications · Statistics 2017-01-20 David C. Bailey

Introduction: molecular geometry, the three-dimensional arrangement of atoms within a molecule, is fundamental to understanding chemical reactivity, physical properties, and biological activity. The prevailing models used to describe…

General Physics · Physics 2026-05-12 Sebastian Ali Sacasa-Cespedes

The automatic analysis of chemical literature has immense potential to accelerate the discovery of new materials and drugs. Much of the critical information in patent documents and scientific articles is contained in figures, depicting the…

Computer Vision and Pattern Recognition · Computer Science 2024-08-29 Lucas Morin , Martin Danelljan , Maria Isabel Agea , Ahmed Nassar , Valery Weber , Ingmar Meijer , Peter Staar , Fisher Yu

In this paper, we consider a molecular descriptor called the Wiener polarity index, which is defined as the number of unordered pairs of vertices at distance three in a graph. Molecular descriptors play a fundamental role in chemistry,…

Combinatorics · Mathematics 2019-04-09 Niko Tratnik

In \cite{2012a}, Abdo and Dimitov defined the total irregularity of a graph $G=(V,E)$ as \hskip3.3cm $\rm irr_{t}$$(G) = \frac{1}{2}\sum_{u,v\in V}|d_{G}(u)-d_{G}(v)|, $ \noindent where $d_{G}(u)$ denotes the vertex degree of a vertex $u\in…

Combinatorics · Mathematics 2014-04-04 Yingxue Zhu , Lihua You , Jieshan Yang

We introduce a novel method, called Dispersion Entropy for Graph Signals, $DE_G$, as a powerful tool for analysing the irregularity of signals defined on graphs. We demonstrate the effectiveness of $DE_G$ in detecting changes in the…

Combinatorics · Mathematics 2023-04-03 John Stewart Fabila-Carrasco , Chao Tan , Javier Escudero

A graph is regularizable if it is possible to assign weights to its edges so that all nodes have the same degree. Weights can be positive, nonnegative or arbitrary as soon as the regularization degree is not null. Positive and nonnegative…

Social and Information Networks · Computer Science 2017-07-03 Massimo Franceschet , Enrico Bozzo

Analysis of chemical graphs is becoming a major research topic in computational molecular biology due to its potential applications to drug design. One of the major approaches in such a study is inverse quantitative structure…

Computational Engineering, Finance, and Science · Computer Science 2020-12-04 Tatsuya Akutsu , Hiroshi Nagamochi

Undetected anomalies in time series can trigger catastrophic failures in safety-critical systems, such as chemical plant explosions or power grid outages. Although many detection methods have been proposed, their performance remains unclear…

This work aims to assess the molecular architectures of anti-tuberculosis drugs using both degree-based topological indices and novel distance based indices. We can represent the chemical arrangement as a graph, with atoms serving as the…

Biomolecules · Quantitative Biology 2024-11-06 D. C. Gunawardhana , G. H. J. Lanel , K. K. K. R. Perera , A. G. M. J. Gunaratna

Regular $A_n$-, $B_n$- and $C_n$-crystals are edge-colored directed graphs, with ordered colors $1,2,...,n$, which are related to representations of quantized algebras $U_q(\mathfrak{sl}_{n+1})$, $U_q(\mathfrak{sp}_{2n})$ and…

Combinatorics · Mathematics 2012-08-17 Vladimir Danilov , Alexander Karzanov , Gleb Koshevoy

We consider the universality for the trace invariants of $c_1 N \times \cdots \times c_D N$ tensors with i.i.d. complex random elements. In the case $c_1 = \cdots = c_D$, Gurau derived the universality in the limit $N \to \infty$ by…

Mathematical Physics · Physics 2016-03-31 Nana Kanbe

In this paper, we tackle the problem of measuring similarity among graphs that represent real objects with noisy data. To account for noise, we relax the definition of similarity using the maximum weighted co-$k$-plex relaxation method,…

Data Structures and Algorithms · Computer Science 2016-01-26 Maritza Hernandez , Arman Zaribafiyan , Maliheh Aramon , Mohammad Naghibi

We consider here 6-regular plane graphs whose faces have size 1, 2 or 3. In Section 2 a practical enumeration method is given that allowed us to enumerate them up to 53 vertices. Subsequently, in Section 3 we enumerate all possible symmetry…

Combinatorics · Mathematics 2010-07-28 Michel Deza , Mathieu Dutour Sikiric