On a Discrete Chaos Induction Via an Aperiodic Kicks Pattern

2017 ◽  
Vol 12 (4) ◽  
Author(s):  
Mehdi Nategh ◽  
Dumitru Baleanu ◽  
Mohammad Reza Valinejad
Keyword(s):  
Time Scales ◽  
Time Dependent ◽  
Encryption Scheme ◽  
Chaotic Encryption ◽  
Dynamic Problems ◽  
Plain Text ◽  
Discrete Chaos ◽  
The Senses

In this work, a class of kicked systems perturbed with an irregular kicks pattern is studied and formation of a chaos in the senses of Devaney and Li–Yorke in the corresponding discretized system is investigated. Beside a discussion on chaotic stability, an example is presented. Then, the existence of a period three orbit of a 2D map which governs a class of dynamic problems on time scales is studied. As an application, a chaotic encryption scheme for a time-dependent plain text with the help of chaos induction in the sense of Li–Yorke is presented.

Hiding Data in Plain Sight: Towards Provably Unbreakable Encryption with Short Secret Keys and One-Way Functions

2021 ◽  
Author(s):  
Mircea-Adrian Digulescu
Keyword(s):  
Encryption Scheme ◽  
Secret Key ◽  
Small Probability ◽  
Random Data ◽  
Computing Power ◽  
Plain Text ◽  
Secret Keys ◽  
The One ◽  
One Way Function ◽  
The Cost

It has long been known that cryptographic schemes offering provably unbreakable security exist, namely the One Time Pad (OTP). The OTP, however, comes at the cost of a very long secret key - as long as the plain-text itself. In this paper we propose an encryption scheme which we (boldly) claim offers the same level of security as the OTP, while allowing for much shorter keys, of size polylogarithmic in the computing power available to the adversary. The Scheme requires a large sequence of truly random words, of length polynomial in the both plain-text size and the logarithm of the computing power the adversary has. We claim that it ensures such an attacker cannot discern the cipher output from random data, except with small probability. We also show how it can be adapted to allow for several plain-texts to be encrypted in the same cipher output, with almost independent keys. Also, we describe how it can be used in lieu of a One Way Function.

3D Chaotic Encryption Scheme for Compressed Image

2010 ◽  
Vol 30 (2) ◽  
pp. 399-404
Author(s):  
李娟 Li Juan ◽  
冯勇 Feng Yong ◽  
杨旭强 Yang Xuqiang
Keyword(s):  
Encryption Scheme ◽  
Chaotic Encryption

scholarly journals A novel chaotic encryption scheme based on efficient secret keys and confusion technique for confidential of DICOM images

2020 ◽  
Vol 20 ◽  
pp. 100396 ◽  
Author(s):  
Sareh Mortajez ◽  
Marziyeh Tahmasbi ◽  
Javad Zarei ◽  
Amir Jamshidnezhad
Keyword(s):  
Encryption Scheme ◽  
Chaotic Encryption ◽  
Secret Keys

Local non-integer order dynamic problems on time scales revisited

2017 ◽  
Vol 6 (2) ◽  
pp. 486-498 ◽  
Author(s):  
Abdolali Neamaty ◽  
Mehdi Nategh ◽  
Bahram Agheli
Keyword(s):  
Time Scales ◽  
Dynamic Problems ◽  
Integer Order

scholarly journals Analyzing Monthly Extreme Sea Levels with a Time-Dependent GEV Model

2007 ◽  
Vol 24 (5) ◽  
pp. 894-911 ◽  
Author(s):  
Fernando J. Méndez ◽  
Melisa Menéndez ◽  
Alberto Luceño ◽  
Inigo J. Losada
Keyword(s):  
San Francisco ◽  
Time Scales ◽  
Southern Oscillation ◽  
Efficient Estimation ◽  
Time Dependent ◽  
Seasonal Effects ◽  
Complete Analysis ◽  
Sea Levels ◽  
Data Variability ◽  
Extreme Sea Levels

Abstract A statistical model to analyze different time scales of the variability of extreme high sea levels is presented. This model uses a time-dependent generalized extreme value (GEV) distribution to fit monthly maxima series and is applied to a large historical tidal gauge record (San Francisco, California). The model allows the identification and estimation of the effects of several time scales—such as seasonality, interdecadal variability, and secular trends—in the location, scale, and shape parameters of the probability distribution of extreme sea levels. The inclusion of seasonal effects explains a large amount of data variability, thereby allowing a more efficient estimation of the processes involved. Significant correlation with the Southern Oscillation index and the nodal cycle, as well as an increase of about 20% for the secular variability of the scale parameter have been detected for the particular dataset analyzed. Results show that the model is adequate for a complete analysis of seasonal-to-interannual sea level extremes providing time-dependent quantiles and confidence intervals.

TIME-DEPENDENT SSC COOLING EFFECTS ON BLAZAR EMISSION

2014 ◽  
Vol 28 ◽  
pp. 1460181
Author(s):  
MICHAEL ZACHARIAS ◽  
REINHARD SCHLICKEISER
Keyword(s):  
Time Scales ◽  
Doubling Time ◽  
Spectral Energy Distribution ◽  
Nonlinear Behavior ◽  
Time Dependent ◽  
Spectral Energy ◽  
Relativistic Electrons ◽  
Linear Approach ◽  
Standard Linear ◽  
Cooling Effects

Blazars are among the most violent sources in the cosmos exhibiting flaring states with remarkably different variability time scales. Especially rapid flares with flux doubling time scales of the order of minutes have been puzzling for quite some time. Many modeling attempts use the well known linear and steady-state scenario for the cooling and emission processes in the jet, albeit the obvious strongly time-dependent nature of flares. Due to the feedback of the self-produced synchrotron radiation with additional scattering by the relativistic electrons, the synchrotron-self Compton (SSC) effect is inherently time-dependent. Recently, an analytical analysis on the effects of this nonlinear behavior has been presented. Here, we summarize these results concerning the effect of the time-dependent SSC cooling on the spectral energy distribution (SED), and the synchrotron lightcurves of blazars. For that, we calculated analytically the synchrotron, SSC and external Compton (EC) component of the SED, giving remarkably different spectral features compared to the standard linear approach. The resulting fluxes strongly depend on the parameters, and SSC might have a strong effect even in sources with strong external photon fields (such as FSRQs). For the synchrotron lightcurve we considered the effects of retardation, including the geometry of the source. The retardation might smear out some effects of the time-dependent cooling, but since lightcurves and SEDs have to be fitted simultaneously with the same set of parameters, the results give nonetheless important clues about the source. Thus, we argue for a wide utilization of the time-dependent treatment in modeling (especially rapid) blazar flares, since it accounts for features in the SED and the lightcurves that are usually accounted for by introducing several breaks in the electron distribution without any physical justification.

scholarly journals A Key Space Enhanced Chaotic Encryption Scheme for Physical Layer Security in OFDM-PON

2017 ◽  
Vol 9 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Meihua Bi ◽  
Xiaosong Fu ◽  
Xuefang Zhou ◽  
Lu Zhang ◽  
Guowei Yang ◽  
...  
Keyword(s):  
Physical Layer Security ◽  
Physical Layer ◽  
Encryption Scheme ◽  
Chaotic Encryption ◽  
Key Space

Time-dependent treatment of scattering: potential referenced and kinetic energy referenced modified Cayley approaches to atom–diatom collisions and time-scale separations

1992 ◽  
Vol 70 (2) ◽  
pp. 686-692
Author(s):  
Omar A.Sharafeddin ◽  
Donald J. Kouri ◽  
David K. Hoffman
Keyword(s):  
Kinetic Energy ◽  
Potential Energy ◽  
Time Scales ◽  
Quantum Dynamics ◽  
Time Dependent ◽  
Multiple Time Scales ◽  
Binding Potential ◽  
Multiple Time ◽  
General Reference ◽  
Cayley Transformation

The time-dependent Lippmann–Schwinger equation describing atom–diatom collisions is expressed in terms of a general reference Hamiltonian, Hr, whose dynamics are easily solved in one representation, and a corresponding disturbance Hamiltonian, Hd, whose dynamics are easily solved in a different representation. The wavefunction at time t + τ t is then expressed in terms of its value at a previous time t by means of a simple quadrature approximation. The resulting expression for ψ(t + τ) has a form similar to that occurring in earlier numerical unitary solutions to the time-dependent Schrodinger equation via a Cayley transformation. The structure of the new equations is made explicit for (a) the choice where Hr is taken to be the kinetic energy and Hd is the potential energy and (b) the choice where Hr is taken to be the potential energy and Hd is the kinetic energy. In addition, we also deal with several alternatives for treating the binding potential of the diatom. Several alternatives for choosing representations are then explored for reducing the equations to a form amenable to computation. The short time structure of the equations is discussed in terms of a multiple time-scales analysis. Keywords: molecular collisions, multiple time scales, quantum dynamics.

Sign in / Sign up

Export Citation Format

Share Document