The Twisted Heisenberg Algebra Uh,w(H(4)){\cal U}_{h,w}({\cal H}(4))

A two parametric deformation of the enveloping Heisenberg algebra ${\cal H}(4)$ which appear as a combination of the standard and a nonstandard quantization given by Ballesteros and Herranz is defined and proved to be Ribbon Hopf algebra. The universal ${\cal R}$-matrix and its associated quantum group are constructed. New solution of Braid group are obtained. The contribution of these parameters in invariants of links and WZW model are analyzed. General results for twisted Ribbon Hopf algebra are derived.Comment: 21 pages, latex, no figures, Somes comments and references has been added, version to be published in Journal of Mathematical Physic

Ecological Diagnosis and Diversity Structure of the Forest Birds Community in Machroha Forest (Souk Ahras – Northeastern Algeria)

Machroha forest is a large hot spot of biodiversity of northeastern region of Algeria. It is dominated by several species of oak tree that can contribute to the conservation of many animals such as birds. Our study was carried out from February 2019 to July 2021, in order to diagnosis the ecological status of forest birds and their dynamics. Our results reported that this forest was including 19.21% of the Algerian avifauna diversity. We recorded 78 species of birds classified in 32 families. The main species were sedentary with an insectivorous trophic categories and terrestrial guild. Three species observed in this forest were threatened, the Dartford warbler, the European turtle dove and the Egyptian vulture. We reported many factors that affected bird’s population dynamics “such as population isolation and habitat structure”. So, in the future the monitoring of the bird’s population must follow a management plan and proposing a new national classification status “wildlife refuge”

La communication écrite numérique :enquête sur le cyberviolence

Résumé : La question des échanges en ligne est digne d’intérêt dans la mesure où la violence verbale demeure omniprésente dans ce monde virtuel. Notre étude porte sur la cyberviolence en milieu scolaire. Elle s’inscrit dans une perspective sociolinguistique. Il s’agit de mettre l’accent sur l’émergence de la violence verbale dans les pratiques langagières des élèves algériens sur le réseau social Facebook. Notre analyse vise à rendre compte du processus global de la transgression des normes fixées par l’institution éducative. Les perspectives à partir desquelles nous abordons la violence verbale nous permettront de définir ses actes, de les repérer et les analyser linguistiquement.  Mots-clés : communication écrite, cyberviolence, monde virtuel, réseau social, normes

Buckling Cascade of Thin Plates: Forms, Constraints and Similarity

We experimentally study compression of thin plates in rectangular boxes with variable height. A cascade of buckling is generated. It gives rise to a self-similar evolution of elastic reaction of plates with box height which surprisingly exhibits repetitive vanishing and negative stiffness. These features are understood from properties of Euler's equation for elastica

Securing vehicular cloud networks

Vehicular Cloud Networks (VCN) is the network that ensures mobility and availability of resources allowing new services and applications like Network as a Service (NaaS), STorage as a Service (STaaS), Computation as a Service (CompaaS) and Cooperation as a Service (CaaS). In this paper, we propose a solution to secure the Vehicular Cloud Network (VCN). Our challenge in this work is to adapt the PKI architecture, which is mainly used in wired networks to be used in VCN. To propose a security solution for Vehicular Cloud Networks (VCN), our work is based on three steps; the first one is to make network architecture study, where we tried to highlight the main network components. The second step is to propose the security solution architecture. Finally, the last step is to program a test and validate the solution using a simulation

Atypical Representations of Uq(sl(N))U_{q}(sl(N)) at Roots of Unity

We show how to adapt the Gelfand-Zetlin basis for describing the atypical representation of ${\cal U}_{\displaystyle{q}}(sl(N))$ when $q$ is root of unity. The explicit construction of atypical representation is presented in details for $N=3$.Comment: 18 pages, Tex-file and 2 figures. Uuencoded, compressed and tared archive of plain tex file and postscript figure file. Upon uudecoding, uncompressing and taring, tex the file atypique.te

Density, speed of sound and refractive index of mixtures containing 2-phenoxyethanol with propanol or butanol at various temperatures

In this work, we reported the new experimental data of densities, speeds of sound, and refractive indices for four binary mixtures: {2-phenoxyethanol (2PhEE) + 1-propanol or 2-propanol or 1-butanol or 2-butanol) over the entire composition range and at temperatures of (293.15, 303.15, 313.15 and 323.15) K and at pressure p = 0.1 MPa. From these experimental data, thermodynamics properties: excess molar volume, isentropic compressibility, deviation in isentropic compressibility and deviation in refractive indices were calculated. Excess molar volume, deviation in isentropic compressibility and deviation in refractive indices data have been correlated using the Redlich–Kister equation. From the obtained results, a discussion was carried out in terms of nature of intermolecular interactions and structure factors in these binary mixtures

Coiling Instabilities in Multilamellar Tubes

Myelin figures are densely packed stacks of coaxial cylindrical bilayers that are unstable to the formation of coils or double helices. These myelin figures appear to have no intrinsic chirality. We show that such cylindrical membrane stacks can develop an instability when they acquire a spontaneous curvature or when the equilibrium distance between membranes is decreased. This instability breaks the chiral symmetry of the stack and may result in coiling. A unilamellar cylindrical vesicle, on the other hand, will develop an axisymmetric instability, possibly related to the pearling instability.Comment: 6 pages, 2 figure