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1,912 Results Found

  • Article
  • Open Access
8 Citations
2,829 Views
25 Pages

10 November 2022

Band subset selection (BSS) is one of the ways to implement band selection (BS) for a hyperspectral image (HSI). Different from conventional BS methods, which select bands one by one, BSS selects a band subset each time and preserves the best one fro...

  • Feature Paper
  • Article
  • Open Access
4 Citations
7,516 Views
22 Pages

Loop Representation of Wigner’s Little Groups

  • Sibel Başkal,
  • Young S. Kim and
  • Marilyn E. Noz

23 June 2017

Wigner’s little groups are the subgroups of the Lorentz group whose transformations leave the momentum of a given particle invariant. They thus define the internal space-time symmetries of relativistic particles. These symmetries take different mathe...

  • Article
  • Open Access
4 Citations
2,518 Views
14 Pages

Inner Product Groups and Riesz Representation Theorem

  • Alireza Pourmoslemi,
  • Tahereh Nazari and
  • Mehdi Salimi

15 October 2021

In this paper, we introduce an inner product on abelian groups and, after investigating the basic properties of the inner product, we first show that each inner product group is a torsion-free abelian normed group. We give examples of such groups and...

  • Article
  • Open Access
1 Citations
4,415 Views
37 Pages

16 March 2016

It is shown that, for both compact and non-compact Lie groups, vector-coherent-state methods provide straightforward derivations of holomorphic representations on symmetric spaces. Complementary vector-coherent-state methods are introduced to derive...

  • Article
  • Open Access
1 Citations
1,905 Views
14 Pages

Artificial Neural Networks Using Quiver Representations of Finite Cyclic Groups

  • Lucky Cahya Wanditra,
  • Intan Muchtadi-Alamsyah and
  • Dellavitha Nasution

24 November 2023

In this paper, we propose using quiver representations as a tool for understanding artificial neural network algorithms. Specifically, we construct these algorithms by utilizing the group algebra of a finite cyclic group as vertices and convolution t...

  • Article
  • Open Access
5 Citations
2,225 Views
16 Pages

4 January 2024

We show that, as in the case of the principle of minimum action in classical and quantum mechanics, there exists an even more general principle in the very fundamental structure of quantum spacetime: this is the principle of minimal group representat...

  • Article
  • Open Access
2 Citations
1,853 Views
17 Pages

Grouped Contrastive Learning of Self-Supervised Sentence Representation

  • Qian Wang,
  • Weiqi Zhang,
  • Tianyi Lei and
  • Dezhong Peng

31 August 2023

This paper proposes a method called Grouped Contrastive Learning of self-supervised Sentence Representation (GCLSR), which can learn an effective and meaningful representation of sentences. Previous works maximize the similarity between two vectors t...

  • Article
  • Open Access
2,499 Views
15 Pages

Sampling Associated with a Unitary Representation of a Semi-Direct Product of Groups: A Filter Bank Approach

  • Antonio G. García,
  • Miguel Angel Hernández-Medina and
  • Gerardo Pérez-Villalón

12 April 2019

An abstract sampling theory associated with a unitary representation of a countable discrete non abelian group G, which is a semi-direct product of groups, on a separable Hilbert space is studied. A suitable expression of the data samples, the use of...

  • Article
  • Open Access
24 Citations
8,774 Views
64 Pages

9 June 2020

In 1969, Jean-Marie Souriau introduced a “Lie Groups Thermodynamics” in Statistical Mechanics in the framework of Geometric Mechanics. This Souriau’s model considers the statistical mechanics of dynamic systems in their “space...

  • Article
  • Open Access
4 Citations
2,484 Views
12 Pages

Social Representations of Urinary Incontinence in Caregivers and General Population: A Focus Group Study

  • Lea Peroni,
  • Didier Armaingaud,
  • Tassadit Yakoubi and
  • Monique Rothan-Tondeur

Urinary incontinence (UI) is a major public health problem. Although trivialized, it affects nearly 9% of the world’s population and its prevalence increases with age. It affects many people living in nursing homes. In the literature, there is...

  • Article
  • Open Access
26 Citations
8,398 Views
19 Pages

9 January 2017

Restricted by technical and budget constraints, hyperspectral images (HSIs) are usually obtained with low spatial resolution. In order to improve the spatial resolution of a given hyperspectral image, a new spatial and spectral image fusion approach...

  • Article
  • Open Access
6 Citations
2,570 Views
26 Pages

7 October 2023

Hyperspectral image (HSI) super-resolution is a vital technique that generates high spatial-resolution HSI (HR-HSI) by integrating information from low spatial-resolution HSI with high spatial-resolution multispectral image (MSI). However, existing s...

  • Article
  • Open Access
2 Citations
3,015 Views
20 Pages

Symptoms resulting from childhood trauma can negatively impact socioemotional well-being and school performance during early adolescence unless positive changes in attachment security and mental representations of significant relationships occur. A s...

  • Article
  • Open Access
16 Citations
4,664 Views
19 Pages

24 May 2018

Spectral-spatial classification has been widely applied for remote sensing applications, especially for hyperspectral imagery. Traditional methods mainly focus on local spatial similarity and neglect nonlocal spatial similarity. Recently, nonlocal se...

  • Article
  • Open Access
10 Citations
2,540 Views
19 Pages

6 May 2023

Infrared (IR) Image preprocessing is aimed at image denoising and enhancement to help with small target detection. According to the sparse representation theory, the IR original image is low rank, and the coefficient shows a sparse character. The low...

  • Article
  • Open Access
1 Citations
2,325 Views
25 Pages

10 April 2024

We geometrically derive the explicit form of the unitary representation of the Poincaré group for vector-valued wave functions and use it to apply speed-of-light boosts to a simple polarization basis to end up with a Hawton–Baylis photon...

  • Article
  • Open Access
2 Citations
2,135 Views
9 Pages

20 July 2021

Although describing very different physical systems, both the Klein–Gordon equation for tachyons (m2<0) and the Helmholtz equation share a remarkable property: a unitary and irreducible representation of the corresponding invariance group on a sui...

  • Feature Paper
  • Article
  • Open Access
1,405 Views
27 Pages

28 August 2025

Permutations on a set, endowed with function composition, build a group called a symmetric group. In addition to their algebraic structure, symmetric groups have two metrics that are of particular interest to us here: the Cayley distance and the Kend...

  • Article
  • Open Access
10 Citations
7,778 Views
20 Pages

27 June 2013

Henri Poincaré formulated the mathematics of Lorentz transformations, known as the Poincaré group. He also formulated the Poincaré sphere for polarization optics. It is shown that these two mathematical instruments can be derived from the two-by-two...

  • Communication
  • Open Access
2 Citations
1,783 Views
9 Pages

11 May 2023

We study a projective unitary representation of the product G=G˜×G, where G is a locally compact Abelian group and G^ is its dual consisting of characters on G. It is proven that the representation is irreducible, which allows us to defin...

  • Feature Paper
  • Article
  • Open Access
1 Citations
2,495 Views
10 Pages

Seven Small Simple Groups Not Previously Known to Be Galois Over Q

  • Luis Dieulefait,
  • Enric Florit and
  • Núria Vila

13 June 2022

In this note we realize seven small simple groups as Galois groups over Q. The technique that we employ is the determination of the images of Galois representations attached to modular and automorphic forms, relying in two cases on recent results of...

  • Feature Paper
  • Article
  • Open Access
66 Views
34 Pages

21 January 2026

In this paper, we study Spin*(8)-Higgs bundles over compact Riemann surfaces, extending the work of Bradlow, García-Prada, and Gothen on SO*(8). The group Spin*(8) is exceptional among classical real forms, as its complexification Spin(8,C) ad...

  • Article
  • Open Access
5 Citations
4,838 Views
11 Pages

26 July 2021

The present article reviews the multiple applications of group theory to the symmetry problems in physics. In classical physics, this concerns primarily relativity: Euclidean, Galilean, and Einsteinian (special). Going over to quantum mechanics, we f...

  • Article
  • Open Access
4 Citations
3,238 Views
21 Pages

Heisenberg–Weyl Groups and Generalized Hermite Functions

  • Enrico Celeghini,
  • Manuel Gadella and
  • Mariano A. del Olmo

12 June 2021

We introduce a multi-parameter family of bases in the Hilbert space L2(R) that are associated to a set of Hermite functions, which also serve as a basis for L2(R). The Hermite functions are eigenfunctions of the Fourier transform, a property that is,...

  • Article
  • Open Access
34 Citations
12,150 Views
14 Pages

All ethnic/racial terminology may be seen as a form of representation, whereby meanings are generated by a range of social categorizers in settings of popular culture, political discourse, and statistical governmentality. This paper investigates thes...

  • Review
  • Open Access
11 Citations
4,768 Views
40 Pages

Groups, Special Functions and Rigged Hilbert Spaces

  • Enrico Celeghini,
  • Manuel Gadella and
  • Mariano A. del Olmo

27 July 2019

We show that Lie groups and their respective algebras, special functions and rigged Hilbert spaces are complementary concepts that coexist together in a common framework and that they are aspects of the same mathematical reality. Special functions se...

  • Article
  • Open Access
1 Citations
2,181 Views
7 Pages

On the Unitary Representations of the Braid Group B6

  • Malak M. Dally and
  • Mohammad N. Abdulrahim

9 November 2019

We consider a non-abelian leakage-free qudit system that consists of two qubits each composed of three anyons. For this system, we need to have a non-abelian four dimensional unitary representation of the braid group B 6 to obtain a totally l...

  • Article
  • Open Access
7 Citations
4,574 Views
7 Pages

An explanation of the origin of dark matter is suggested in this work. The argument is based on symmetry considerations about the concept of mass. In Wigner’s view, the rest mass and the spin of a free elementary particle in flat space-time are...

  • Article
  • Open Access
7 Citations
2,886 Views
54 Pages

Compact Lie Groups, Generalised Euler Angles, and Applications

  • Sergio Luigi Cacciatori and
  • Antonio Scotti

20 September 2022

This is mainly a review of an intense 15-year long collaboration between the authors on explicit realisations of compact Lie groups and their applications. Starting with an elementary example, we will illustrate the main idea at the foundation of the...

  • Article
  • Open Access
890 Views
19 Pages

25 September 2025

Just as Gauss’s interpretation of complex numbers as points in a number plane in the form of a suitably formulated axiom found its way into the vector representation of Fourier transforms, this is the case with Euler’s formula and Riemann...

  • Article
  • Open Access
6 Citations
2,067 Views
27 Pages

6 July 2022

Large-scale group decision-making (LS-GDM) problems are common in the daily life of human beings. Both information fusion and computing with words (CWW) technologies in LS-GDM suffer from challenges. In the current research, a proportional hesitant f...

  • Article
  • Open Access
1,297 Views
37 Pages

12 March 2025

We develop a new unsupervised symmetry learning method that starts with raw data and provides the minimal generator of an underlying Lie group of symmetries, together with a symmetry-equivariant representation of the data, which turns the hidden symm...

  • Article
  • Open Access
2,663 Views
5 Pages

22 March 2019

Let k be an algebraically closed field of prime characteristic and let G be a semisimple, simply connected, linear algebraic group. It is an open problem to find the cohomology of line bundles on the flag variety G / B , where B is a Borel sub...

  • Article
  • Open Access
2,521 Views
40 Pages

Beltrami Equations on Rossi Spheres

  • Elisabetta Barletta,
  • Sorin Dragomir and
  • Francesco Esposito

25 January 2022

Beltrami equations L¯t(g)=μ(·,t)Lt(g) on S3 (where Lt, |t|<1, are the Rossi operators i.e., Lt spans the globally nonembeddable CR structure H(t) on S3 discovered by H. Rossi) are derived such that to describe quasiconformal mapping...

  • Article
  • Open Access
32 Citations
4,434 Views
26 Pages

17 March 2022

Discriminative feature learning is the key to remote sensing scene classification. Previous research has found that most of the existing convolutional neural networks (CNN) focus on the global semantic features and ignore shallower features (low-leve...

  • Article
  • Open Access
1 Citations
7,051 Views
17 Pages

25 February 2010

Several situations of general interest, in which the symmetry groups usually applied to spectroscopy problems need to be extended, are reviewed. It is emphasized that any symmetry group of geometrical operations to be used in Molecular Spectroscopy s...

  • Article
  • Open Access
1 Citations
2,084 Views
19 Pages

3 August 2023

Representations of braid group Bn on n≥2 strands by automorphisms of a free group of rank n go back to Artin. In 1991, Kauffman introduced a theory of virtual braids, virtual knots, and links. The virtual braid group VBn on n≥2 strands is an ex...

  • Article
  • Open Access
7 Citations
2,932 Views
21 Pages

30 March 2022

Space-time adaptive processing (STAP) plays an essential role in clutter suppression and moving target detection in airborne radar systems. The main difficulty is that independent and identically distributed (i.i.d) training samples may not be suffic...

  • Article
  • Open Access
1 Citations
1,809 Views
17 Pages

21 December 2023

Motivated by a ternary generalization of the Pauli exclusion principle proposed by R. Kerner, we propose a notion of a Z3-skew-symmetric covariant SO(3)-tensor of the third order, consider it as a 3-dimensional matrix, and study the geometry of the 1...

  • Article
  • Open Access
9 Citations
3,398 Views
20 Pages

30 October 2019

A data center with a large number of servers, large storage, and many network devices requires power for cooling to reduce heat generation, air conditioning, and emergency power generation facilities, in addition to power for operation internally con...

  • Article
  • Open Access
1 Citations
504 Views
28 Pages

24 December 2025

Surface crack detection and temporal evolution analysis are fundamental tasks in remote sensing and photogrammetry, providing critical information for slope stability assessment, infrastructure safety inspection, and long-term geohazard monitoring. H...

  • Article
  • Open Access
1 Citations
3,804 Views
22 Pages

7 August 2019

The momentum-independent Casimir operators of the homogeneous spin-Lorentz group are employed in the construction of covariant projector operators, which can decompose anyone of its reducible finite-dimensional representation spaces into irreducible...

  • Article
  • Open Access
9 Citations
3,127 Views
18 Pages

Achieving high-quality reconstructions of images is the focus of research in image compressed sensing. Group sparse representation improves the quality of reconstructed images by exploiting the non-local similarity of images; however, block-matching...

  • Article
  • Open Access
1,236 Views
12 Pages

7 November 2024

The notion of matched pair (F,G,▹,◃) of finite groups was introduced by Takeuchi in 1981, which is equivalent to a factorization of the group F⋈G. We find in this paper some sufficient conditions when equations νm(F⋈G)=ν...

  • Article
  • Open Access
2 Citations
2,862 Views
15 Pages

1 June 2023

Although emotions occupy an important place in Alevism, their representation in Alevi history and the present has not yet been sufficiently researched. This study addresses this desideratum and discusses the representation and codification of emotion...

  • Article
  • Open Access
7 Citations
3,163 Views
18 Pages

13 October 2018

In this paper, we propose a boosting synthetic aperture radar (SAR) image despeckling method based on non-local weighted group low-rank representation (WGLRR). The spatial structure information of SAR images leads to the similarity of the patches. Fu...

  • Article
  • Open Access
4 Citations
2,395 Views
18 Pages

Multi-Perspective Representation to Part-Based Graph for Group Activity Recognition

  • Lifang Wu,
  • Xianglong Lang,
  • Ye Xiang,
  • Qi Wang and
  • Meng Tian

24 July 2022

Group activity recognition that infers the activity of a group of people is a challenging task and has received a great deal of interest in recent years. Different from individual action recognition, group activity recognition needs to model not only...

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