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A multi layered encryption framework using intuitionistic fuzzy graphs and graph theoretic domination for secure communication networks
2025
Secure communication is essential in today’s rapidly evolving digital environment, and strong encryption methods are required to protect private data from unwanted access. The aim of this study is to strengthen the security and complexity of encrypted communications by adopting a new form of cryptographic encryption technique based on the principles of an intuitionistic fuzzy graph. Key graph-theoretic measures, such as domination number, vertex categorization (alpha-strong, beta-strong, and gamma-strong), vertex order coloring, and chromatic number, play important roles in this process. Domination number finds the key vertices of the network, while vertex strength categorization and fuzzy graph coloring provide multiple encryption layers, hence the encoded message is highly resistant to decryption unless a proper key is used. The chromatic number offers further security through various patterns of vertex coloring. The comparative analysis shows the proposed approach to be superior compared to RSA, AES, ECC, and Blowfish due to its increased security, computational efficiency, and resilience to attacks. This framework can be applied to the protection of banking PINs, military access codes, government identification numbers, cryptographic keys, and medical records, so it is an extremely versatile solution for protecting sensitive data. This multi-step approach to encryption through the proposed technique ensures safe transfer and efficient encoding as it establishes a complicated framework.
Journal Article
From Vertex Operator Algebras to Conformal Nets and Back
by
Kawahigashi, Yasuyuki
,
Carpi, Sebastiano
,
Longo, Roberto
in
Conformal invariants
,
Vertex operator algebras
2018
We consider unitary simple vertex operator algebras whose vertex operators satisfy certain energy bounds and a strong form of
locality and call them strongly local. We present a general procedure which associates to every strongly local vertex operator algebra
Some results on 3-monochromatic vertex index
2026
A tree T in a vertex colored graph G is called a vertex-monochromatic tree if all the internal vertices of T have the same color. For S ⊆ V(G), a vertex-monochromatic S-tree in G is a vertex-monochromatic tree of G containing the vertices of S. For a connected graph G and a given integer k with 2 ≤ k ≤ |V(G)|, the k-monochromatic vertex-index mvxk
(G) of G is the maximum number of colors needed such that for each subset S ⊆ V(G) of k vertices, there exists a vertex-monochromatic S-tree. In this paper, we give an upper bound of mvx₃(G). We present all graphs with mvx₃(G) of 3, 4, and verify that almost all simple graphs satisfy mvx₃(G) = n. We investigate the 3-monochromatic vertex-index of a graph G of order n and ω(G) = n − i for 1 ≤ i ≤ 3.
Journal Article
Solving the KPZ equation
2013
We introduce a new concept of solution to the KPZ equation which is shown to extend the classical Cole-Hopf solution. This notion provides a factorisation of the Cole-Hopf solution map into a \"universal\" measurable map from the probability space into an explicitly described auxiliary metric space, composed with a new solution map that has very good continuity properties. The advantage of such a formulation is that it essentially provides a pathwise notion of a solution, together with a very detailed approximation theory. In particular, our construction completely bypasses the Cole-Hopf transform, thus laying the groundwork for proving that the KPZ equation describes the fluctuations of systems in the KPZ universality class. As a corollary of our construction, we obtain very detailed new regularity results about the solution, as well as its derivative with respect to the initial condition. Other byproducts of the proof include an explicit approximation to the stationary solution of the KPZ equation, a well-posedness result for the Fokker-Planck equation associated to a particle diffusing in a rough space-time dependent potential, and a new periodic homogenisation result for the heat equation with a space-time periodic potential. One ingredient in our construction is an example of a non-Gaussian rough path such that the area process of its natural approximations needs to be renormalised by a diverging term for the approximations to converge.
Journal Article
Interlacing families I: Bipartite Ramanujan graphs of all degrees
by
Spielman, Daniel A.
,
Marcus, Adam W.
,
Srivastava, Nikhil
in
Absolute value
,
Adjacency matrix
,
Combinatorics
2015
We prove that there exist infinite families of regular bipartite Ramanujan graphs of every degree bigger than 2. We do this by proving a variant of a conjecture of Bilu and Linial about the existence of good 2-lifts of every graph. We also establish the existence of infinite families of \"irregular Ramanujan\" graphs, whose eigenvalues are bounded by the spectral radius of their universal cover. Such families were conjectured to exist by Linial and others. In particular, we prove the existence of infinite families of (c, d)-biregular bipartite graphs with all nontrivial eigenvalues bounded by $\\sqrt{c-1}+\\sqrt{d-1}$ for all c, d ≥ 3. Our proof exploits a new technique for controlling the eigenvalues of certain random matrices, which we call the \"method of interlacing polynomials.\"
Journal Article
Rationality of W-algebras: principal nilpotent cases
2015
We prove the rationality of all the minimal series principal W-algebras discovered by Frenkel, Kac and Wakimoto, thereby giving a new family of rational and C2-cofinite vertex operator algebras. A key ingredient in our proof is the study of Zhu's algebra of simple W-algebras via the quantized Drinfeld-Sokolov reduction. We show that the functor of taking Zhu's algebra commutes with the reduction functor. Using this general fact we determine the maximal spectrums of the associated graded of Zhu's algebras of vertex operator algebras associated with admissible representations of affine Kac-Moody algebras as well.
Journal Article
GA₂ INDEX OF SOME GRAPH OPERATIONS
2010
Let 𝐺 = (𝑉, 𝐸) be a graph. For 𝑒 = 𝑢𝑣 ∈ 𝐸(𝐺), 𝑛𝑢(𝑒) is the number of vertices of 𝐺 lying closer to 𝑢 than to 𝑣 and 𝑛𝑣(𝑒) is the number of vertices of 𝐺 lying closer to 𝑣 than 𝑢. The 𝐺𝐴₂ index of 𝐺 is defined as
∑
u
v
∈
E
(
G
)
2
n
u
(
e
)
n
v
(
e
)
n
u
(
e
)
+
n
v
(
e
)
. We explore here some mathematical properties and present explicit formulas for this new index under several graph operations.
Journal Article
DETOUR INDEX OF A CLASS OF UNICYCLIC GRAPHS
The detour index of a connected graph is defined as the sum of detour distances between all unordered pairs of vertices. We determine the 𝑛-vertex unicyclic graphs whose vertices on its unique cycle all have degree at least three with the first, the second and the third smallest and largest detour indices respectively for 𝑛 ≥ 7.
Journal Article
Spectral redemption in clustering sparse networks
2013
Spectral algorithms are classic approaches to clustering and community detection in networks. However, for sparse networks the standard versions of these algorithms are suboptimal, in some cases completely failing to detect communities even when other algorithms such as belief propagation can do so. Here, we present a class of spectral algorithms based on a nonbacktracking walk on the directed edges of the graph. The spectrum of this operator is much better-behaved than that of the adjacency matrix or other commonly used matrices, maintaining a strong separation between the bulk eigenvalues and the eigenvalues relevant to community structure even in the sparse case. We show that our algorithm is optimal for graphs generated by the stochastic block model, detecting communities all of the way down to the theoretical limit. We also show the spectrum of the nonbacktracking operator for some real-world networks, illustrating its advantages over traditional spectral clustering.
Journal Article