Evaluating True Cryptographic Key Space Size

Purpose The study sets out to investigate inter- and intraspeaker variation in German infant-directed speech (IDS) and considers the potential impact that the factors gender, parental involvement, and speech material (read vs. spontaneous speech) may have. In addition, we analyze data from 3 time points prior to and after the birth of the child to examine potential changes in the features of IDS and, particularly also, of adult-directed speech (ADS). Here, the gender identity of a speaker is considered as an additional factor. Method IDS and ADS data from 34 participants (15 mothers, 19 fathers) is gathered by means of a reading and a picture description task. For IDS, 2 recordings were made when the baby was approximately 6 and 9 months old, respectively. For ADS, an additional recording was made before the baby was born. Phonetic analyses comprise mean fundamental frequency (f0), variation in f0, the 1st 2 formants measured in /i: ɛ a u:/, and the vowel space size. Moreover, social and behavioral data were gathered regarding parental involvement and gender identity. Results German IDS is characterized by an increase in mean f0, a larger variation in f0, vowel- and formant-specific differences, and a larger acoustic vowel space. No effect of gender or parental involvement was found. Also, the phonetic features of IDS were found in both spontaneous and read speech. Regarding ADS, changes in vowel space size in some of the fathers and in mean f0 in mothers were found. Conclusion Phonetic features of German IDS are robust with respect to the factors gender, parental involvement, speech material (read vs. spontaneous speech), and time. Some phonetic features of ADS changed within the child's first year depending on gender and parental involvement/gender identity. Thus, further research on IDS needs to address also potential changes in ADS.

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Image encryption based on Fractional wavelet transform, Arnold transform with the double random phases in HSV color domain

Recent Advances in Computer Science and Communications ◽

10.2174/2666255813999200918123535 ◽

2020 ◽

Vol 13 ◽

Author(s):

Aarushi Shrivastava ◽

Janki Ballabh Sharma ◽

Sunil Dutt Purohit

Keyword(s):

Wavelet Transform ◽

Image Encryption ◽

Fractional Fourier Transform ◽

Color Image ◽

Random Phase ◽

Arnold Transform ◽

Time Frequency ◽

Key Space ◽

Secret Keys ◽

Fractional Wavelet Transform

Objective: In the recent multimedia technology images play an integral role in communication. Here in this paper, we propose a new color image encryption method using FWT (Fractional Wavelet transform), double random phases and Arnold transform in HSV color domain. Methods: Firstly the image is changed into the HSV domain and the encoding is done using the FWT which is the combination of the fractional Fourier transform with wavelet transform and the two random phase masks are used in the double random phase encoding. In this one inverse DWT is taken at the end in order to obtain the encrypted image. To scramble the matrices the Arnold transform is used with different iterative values. The fractional order of FRFT, the wavelet family and the iterative numbers of Arnold transform are used as various secret keys in order to enhance the level of security of the proposed method. Results: The performance of the scheme is analyzed through its PSNR and SSIM values, key space, entropy, statistical analysis which demonstrates its effectiveness and feasibility of the proposed technique. Stimulation result verifies its robustness in comparison to nearby schemes. Conclusion: This method develops the better security, enlarged and sensitive key space with improved PSNR and SSIM. FWT reflecting time frequency information adds on to its flexibility with additional variables and making it more suitable for secure transmission.

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LOKI: A Lightweight Cryptographic Key Distribution Protocol for Controller Area Networks

2020 IEEE 16th International Conference on Intelligent Computer Communication and Processing (ICCP) ◽

10.1109/iccp51029.2020.9266192 ◽

2020 ◽

Author(s):

Teri Lenard ◽

Roland Bolboaca ◽

Bela Genge

Keyword(s):

Key Distribution ◽

Controller Area Networks ◽

Cryptographic Key

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Coexisting Attractors and Multistability in a Simple Memristive Wien-Bridge Chaotic Circuit

Entropy ◽

10.3390/e21070678 ◽

2019 ◽

Vol 21 (7) ◽

pp. 678 ◽

Cited By ~ 13

Author(s):

Yixuan Song ◽

Fang Yuan ◽

Yuxia Li

Keyword(s):

Chaotic System ◽

Analog Circuit ◽

Random Sequence ◽

Mathematical Expression ◽

Digital Signal ◽

Approximate Entropy ◽

Chaotic Circuit ◽

Coexisting Attractors ◽

Key Space ◽

Sequence Generator

In this paper, a new voltage-controlled memristor is presented. The mathematical expression of this memristor has an absolute value term, so it is called an absolute voltage-controlled memristor. The proposed memristor is locally active, which is proved by its DC V–I (Voltage–Current) plot. A simple three-order Wien-bridge chaotic circuit without inductor is constructed on the basis of the presented memristor. The dynamical behaviors of the simple chaotic system are analyzed in this paper. The main properties of this system are coexisting attractors and multistability. Furthermore, an analog circuit of this chaotic system is realized by the Multisim software. The multistability of the proposed system can enlarge the key space in encryption, which makes the encryption effect better. Therefore, the proposed chaotic system can be used as a pseudo-random sequence generator to provide key sequences for digital encryption systems. Thus, the chaotic system is discretized and implemented by Digital Signal Processing (DSP) technology. The National Institute of Standards and Technology (NIST) test and Approximate Entropy analysis of the proposed chaotic system are conducted in this paper.

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Chaotic Path Planning for 3D Area Coverage Using a Pseudo-Random Bit Generator from a 1D Chaotic Map

Mathematics ◽

10.3390/math9151821 ◽

2021 ◽

Vol 9 (15) ◽

pp. 1821

Author(s):

Lazaros Moysis ◽

Karthikeyan Rajagopal ◽

Aleksandra V. Tutueva ◽

Christos Volos ◽

Beteley Teka ◽

...

Keyword(s):

Path Planning ◽

Chaotic Map ◽

Dynamical Behavior ◽

Area Coverage ◽

Phase Portraits ◽

Planning Strategy ◽

Spline Curves ◽

Key Space ◽

Aerial Vehicle ◽

Discrete Motion

This work proposes a one-dimensional chaotic map with a simple structure and three parameters. The phase portraits, bifurcation diagrams, and Lyapunov exponent diagrams are first plotted to study the dynamical behavior of the map. It is seen that the map exhibits areas of constant chaos with respect to all parameters. This map is then applied to the problem of pseudo-random bit generation using a simple technique to generate four bits per iteration. It is shown that the algorithm passes all statistical NIST and ENT tests, as well as shows low correlation and an acceptable key space. The generated bitstream is applied to the problem of chaotic path planning, for an autonomous robot or generally an unmanned aerial vehicle (UAV) exploring a given 3D area. The aim is to ensure efficient area coverage, while also maintaining an unpredictable motion. Numerical simulations were performed to evaluate the performance of the path planning strategy, and it is shown that the coverage percentage converges exponentially to 100% as the number of iterations increases. The discrete motion is also adapted to a smooth one through the use of B-Spline curves.

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GEOMETRY AND THE IMAGINATION: In Hyperbolic Space, Size Matters

Science ◽

10.1126/science.317.5834.38a ◽

2007 ◽

Vol 317 (5834) ◽

pp. 38a-38a

Author(s):

B. Cipra

Keyword(s):

Hyperbolic Space ◽

Space Size

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Optimal machining conditions and buffer space size for the two-stage case

International Journal of Production Research ◽

10.1080/00207548708919844 ◽

1987 ◽

Vol 25 (3) ◽

pp. 327-336 ◽

Cited By ~ 15

Author(s):

C. P. KOULAMAS ◽

B. K. LAMBERT ◽

M. L. SMITH

Keyword(s):

Two Stage ◽

Buffer Space ◽

Machining Conditions ◽

Space Size

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An improvement of a dynamic cryptographic key assignment scheme in a tree hierarchy

Computers & Mathematics with Applications ◽

10.1016/s0898-1221(99)00042-5 ◽

1999 ◽

Vol 37 (3) ◽

pp. 19-22 ◽

Cited By ~ 14

Author(s):

Min-Shiang Hwang

Keyword(s):

Cryptographic Key ◽

Assignment Scheme

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A Generalized Stability Theorem for Discrete-Time Nonautonomous Chaos System with Applications

Mathematical Problems in Engineering ◽

10.1155/2015/121359 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Mei Zhang ◽

Danling Wang ◽

Lequan Min ◽

Xue Wang

Keyword(s):

Discrete Time ◽

Chaotic Map ◽

Stability Theorem ◽

Pseudorandom Number Generator ◽

Generalized Synchronization ◽

Key Space ◽

Chaos System ◽

Definition Of ◽

Study Designs ◽

Generalized Stability

Firstly, this study introduces a definition of generalized stability (GST) in discrete-time nonautonomous chaos system (DNCS), which is an extension for chaos generalized synchronization. Secondly, a constructive theorem of DNCS has been proposed. As an example, a GST DNCS is constructed based on a novel 4-dimensional discrete chaotic map. Numerical simulations show that the dynamic behaviors of this map have chaotic attractor characteristics. As one application, we design a chaotic pseudorandom number generator (CPRNG) based on the GST DNCS. We use the SP800-22 test suite to test the randomness of four 100-key streams consisting of 1,000,000 bits generated by the CPRNG, the RC4 algorithm, the ZUC algorithm, and a 6-dimensional CGS-based CPRNG, respectively. The numerical results show that the randomness performances of the two CPRNGs are promising. In addition, theoretically the key space of the CPRNG is larger than 21116. As another application, this study designs a stream avalanche encryption scheme (SAES) in RGB image encryption. The results show that the GST DNCS is able to generate the avalanche effects which are similar to those generated via ideal CPRNGs.

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