Search results for "Networking & Telecommunications"
showing 10 items of 962 documents
CORMORANT
2019
People own and carry an increasing number of ubiquitous mobile devices, such as smartphones, tablets, and notebooks. Being small and mobile, those devices have a high propensity to become lost or stolen. Since mobile devices provide access to their owners' digital lives, strong authentication is vital to protect sensitive information and services against unauthorized access. However, at least one in three devices is unprotected, with inconvenience of traditional authentication being the paramount reason. We present the concept of CORMORANT, an approach to significantly reduce the manual burden of mobile user verification through risk-aware, multi-modal biometric, cross-device authentication…
Can individuals’ neutralization techniques be overcome? A field experiment on password policy
2020
Individuals’ lack of adherence to password security policy is a persistent problem for organizations. This problem is especially worrisome because passwords remain the primary authentication mechanism for information systems, and the number of passwords has been increasing. For these reasons, determining methods to improve individuals’ adherence to password-security policies constitutes an important issue for organizations. Extant research has shown that individuals use neutralization techniques, i.e., types of rationalizations, to disregard organizational information-security policies. What has not been determined from extant information security research is whether these neutralizations c…
Detection and Discrimination of Inter-Turn Short Circuit and Demagnetization Faults in PMSMs Based on Structural Analysis
2021
This paper presents a fault diagnosis method based on structural analysis of permanent magnet synchronous motors (PMSMs), focusing on detecting and discriminating two of the most common faults in PMSMs, namely demagnetization and inter-turn short circuit faults. The structural analysis technique uses the dynamic mathematical model of the PMSM in matrix form to evaluate the system’s structural model. After obtaining the analytical redundancy using the over-determined part of the system, it is divided into redundant testable sub-models. Four structured residuals are designed to detect and isolate the investigated faults, which are applied to the system in different time intervals. Finally, th…
Reference-Plane Invariant Method for Measuring Electromagnetic Parameters of Materials
2010
This paper presents a simple and effective wideband method for the determination of material properties, such as the complex index of refraction and the complex permittivity and permeability. The method is explicit (non-iterative) and reference-plane invariant: it uses a certain combination of scattering parameters in conjunction with group-velocity data. This technique can be used to characterize both dielectric and magnetic materials. The proposed method is verified experimentally within a frequency range between 2 to 18 GHz on polytetrafluoroethylene and polyvinylchloride samples. A comprehensive error and stability analysis reveals that, similar to other methods based on transmission/re…
Anharmonic effects on the dynamic behavior’s of Klein Gordon model’s
2021
Abstract This work completes and extends the Ref. Tchakoutio Nguetcho et al. (2017), in which we have focused our attention only on the dynamic behavior of gap soliton solutions of the anharmonic Klein-Gordon model immersed in a parameterized on-site substrate potential. We expand our work now inside the permissible frequency band. These considerations have crucial effects on the response of nonlinear excitations that can propagate along this model. Moreover, working in the allowed frequency band is not only interesting from a physical point of view, it also provides an extraordinary mathematical model, a new class of differential equations possessing vital parameters and vertical singular …
Geometry-Based Statistical Modeling of Non-WSSUS Mobile-to-Mobile Rayleigh Fading Channels
2017
In this paper, we present a novel geometry-based statistical model for small-scale non-wide-sense stationary uncorrelated scattering (non-WSSUS) mobile-to-mobile (M2M) Rayleigh fading channels. The proposed model builds on the principles of plane wave propagation to capture the temporal evolution of the propagation delay and Doppler shift of the received multipath signal. This is different from existing non-WSSUS geometry-based statistical channel models, which are based on a spherical wave propagation approach, that in spite of being more realistic is more mathematically intricate. By considering an arbitrary geometrical configuration of the propagation area, we derive general expressions …
Standard model higher order corrections to the WW gamma/WWZ vertex
1995
Using the S--matrix pinch technique we obtain to one loop order gauge independent $\gamma W^-W^+$ and $Z W^-W^+$ vertices in the context of the standard model, with all incoming momenta off--shell. We show that the vertices so constructed satisfy simple QED--like Ward identities. These gauge invariant vertices give rise to expressions for the magnetic dipole and electric quadrupole form factors of the $W$ gauge boson, which, unlike previous treatments, satisfy the crucial properties of infrared finiteness and perturbative unitarity.
Design of a Compact Dual Circular-Polarized Antenna for L-Band Satellite Applications
2020
In this paper, we propose the design of a dual circular-polarized antenna for L-band applications (1.1-1.6 GHz). The designed antenna has been developed by considering crossed-dipoles on top of which a circular patch has been placed to properly act on the mutual coupling between the dipoles. The dual circular polarization is achieved by feeding dipoles in quadrature. Moreover, to increase the antenna gain and polarization purity at high elevation angles, a fence of passive monopoles has been added. The proposed antenna can profitably used as primary feed of a low-frequency parabolic reflector.
Production and Characterization of the $^{7}$H Resonance
2006
Détecteur MAYA; International audience; The 7H resonance was produced via one-proton transfer reaction between a 8He beam at 15.4A MeV and a 12C gas target. The experimental setup was based on the active-target MAYA which allowed a complete reconstruction of the reaction kinematics. The characterization of the identified 7H events resulted in a resonance energy of 600 keV above the 3H+4n threshold and a resonance width of 100 keV. This study represents the first unambiguous proof of the existence of the 7H state.
New determination of the N-Δ(1232) axial form factors from weak pion production and coherent pion production off nuclei at T2K and MiniBooNE energies…
2010
We re-evaluate our model predictions in Phys. Rev. D 79, 013002 (2009) for different observables in neutrino induced coherent pion production. This comes as a result of the new improved fit to old bubble chamber data of the dominant axial C_5^A nucleon-to-Delta form factor. We find an increase of 20%-30% in the values for the total cross sections. Uncertainties induced by the errors in the determination of C_5^A are computed. Our new results turn out to be compatible within about $1\sigma$ with the former ones. We also stress the existing tension between the recent experimental determination of the \sigma(CC coh \pi^+)}/\sigma(NC coh \pi^0)} $ ratio by the SciBooNE Collaboration and the the…