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Wei-hong Meng

Bio: Wei-hong Meng is an academic researcher from Northern Hospital. The author has contributed to research in topics: Encryption & Digital image processing. The author has an hindex of 2, co-authored 2 publications receiving 352 citations.

Papers
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Journal ArticleDOI
TL;DR: A novel bidirectional diffusion strategy is proposed to promote the efficiency of the most widely investigated permutation-diffusion type image cipher and has a satisfactory security level with a low computational complexity, which renders it a good candidate for real-time secure image transmission applications.
Abstract: Chaos-based image cipher has been widely investigated over the last decade or so to meet the increasing demand for real-time secure image transmission over public networks. In this paper, an improved diffusion strategy is proposed to promote the efficiency of the most widely investigated permutation-diffusion type image cipher. By using the novel bidirectional diffusion strategy, the spreading process is significantly accelerated and hence the same level of security can be achieved with fewer overall encryption rounds. Moreover, to further enhance the security of the cryptosystem, a plain-text related chaotic orbit turbulence mechanism is introduced in diffusion procedure by perturbing the control parameter of the employed chaotic system according to the cipher-pixel. Extensive cryptanalysis has been performed on the proposed scheme using differential analysis, key space analysis, various statistical analyses and key sensitivity analysis. Results of our analyses indicate that the new scheme has a satisfactory security level with a low computational complexity, which renders it a good candidate for real-time secure image transmission applications.

253 citations

Journal ArticleDOI
TL;DR: The proposed scheme introduces a substitution mechanism in the permutation process through a bit-level shuffling algorithm to address the efficiency problem encountered by many existing permutation-substitution type image ciphers.

154 citations

Journal ArticleDOI
TL;DR: In this article , the authors compared post-thrombolytic END between anterior circulation stroke and posterior circulation stroke based on the data from INTRECIS, and found no significant difference in the incidence of end between two groups (3.8% vs 5.2%, adjusted p = 0.406).
Abstract: Anterior circulation stroke (ACS) differs from posterior circulation stroke (PCS) in many ways, but it remains unclear whether there is any difference in early neurological deterioration (END) in two stroke territories. We compared post-thrombolytic END between ACS and PCS based on the data from INTRECIS. We screened patients receiving intravenous 0.9 mg/kg alteplase within 4.5 h in the INTRECIS cohort. According to stroke territory, patients were divided into ACS and PCS groups. The primary outcome was incidence of END, which was defined as an increase in NIHSS score ≥ 4 or death within 24 h from baseline. The secondary outcomes were associated factors of END and 90-day modified Rankin Scale (mRS) distribution. Overall, 1194 patients were enrolled in this study: 942 in ACS group and 252 in PCS group. There was no significant difference in the incidence of END between two groups (3.8% vs 5.2%, adjusted p = 0.406). Atrial fibrillation (adjusted p = 0.012) and TOAST classification (adjusted p = 0.009) were associated with END in ACS, while hypertension history (adjusted p = 0.046) and baseline NIHSS score (adjusted p = 0.011) with END in PCS. END was associated with worse outcome on 90-day mRS in ACS and PCS (adjusted p < 0.001). Based on a prospective nationwide cohort, we provided first report for similar incidence, but different risk factors of post-thrombolytic END in ACS vs PCS patients.Trial Registration-URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02854592.

8 citations


Cited by
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Journal ArticleDOI
TL;DR: A two-dimensional Logistic-adjusted-Sine map (2D-LASM) is proposed that has better ergodicity and unpredictability, and a wider chaotic range than many existing chaotic maps.

496 citations

Journal ArticleDOI
TL;DR: A two-dimensional (2D) Logistic-Sine-coupling map (LSCM) is presented and performance estimations demonstrate that it has better ergodicity, more complex behavior and larger chaotic range than several newly developed 2D chaotic maps.

383 citations

Journal ArticleDOI
TL;DR: This paper proposes a parallel diffusion method that ensures the parallelism of diffusion to the utmost extent and achieves a qualitative improvement in efficiency over traditional streaming diffusion methods.

301 citations

Journal ArticleDOI
TL;DR: This paper introduces a general chaotic framework called the cascade chaotic system (CCS), and introduces a pseudo-random number generator (PRNG) and a data encryption system using a chaotic map generated by CCS.
Abstract: Chaotic maps are widely used in different applications. Motivated by the cascade structure in electronic circuits, this paper introduces a general chaotic framework called the cascade chaotic system (CCS). Using two 1-D chaotic maps as seed maps, CCS is able to generate a huge number of new chaotic maps. Examples and evaluations show the CCS’s robustness. Compared with corresponding seed maps, newly generated chaotic maps are more unpredictable and have better chaotic performance, more parameters, and complex chaotic properties. To investigate applications of CCS, we introduce a pseudo-random number generator (PRNG) and a data encryption system using a chaotic map generated by CCS. Simulation and analysis demonstrate that the proposed PRNG has high quality of randomness and that the data encryption system is able to protect different types of data with a high-security level.

263 citations

Journal ArticleDOI
TL;DR: Simulations and evaluations show that both encryption schemes using bitwise XOR and modulo arithmetic have high security levels, can achieve much faster speeds, and can better adapt to impulse noise and data loss interference than several typical and state-of-the-art encryption schemes.

246 citations