The exponential growth of audio data shared over the internet and communication channels has raised significant concerns about the security and privacy of transmitted information.Due to high processing requirements,tr...The exponential growth of audio data shared over the internet and communication channels has raised significant concerns about the security and privacy of transmitted information.Due to high processing requirements,traditional encryption algorithms demand considerable computational effort for real-time audio encryption.To address these challenges,this paper presents a permutation for secure audio encryption using a combination of Tent and 1D logistic maps.The audio data is first shuffled using Tent map for the random permutation.The high random secret key with a length equal to the size of the audio data is then generated using a 1D logistic map.Finally,the Exclusive OR(XOR)operation is applied between the generated key and the shuffled audio to yield the cipher audio.The experimental results prove that the proposed method surpassed the other techniques by encrypting two types of audio files,as mono and stereo audio files with large sizes up to 122 MB,different sample rates 22,050,44,100,48,000,and 96,000 for WAV and 44,100 sample rates for MP3 of size 11 MB.The results show high Mean Square Error(MSE),low Signal-to-Noise Ratio(SNR),spectral distortion,100%Number of Sample Change Rate(NSCR),high Percent Residual Deviation(PRD),low Correlation Coefficient(CC),large key space 2^(616),high sensitivity to a slight change in the secret key and that it can counter several attacks,namely brute force attack,statistical attack,differential attack,and noise attack.展开更多
In this paper,polyamide(PA)woven fabric was used as the base fabric,and polyurethane(PU)solution containing silica nanoparticles(PU@SiO_(2)NPs)was used as the coating solution to prepare composite tent fabric(PA/PU@Si...In this paper,polyamide(PA)woven fabric was used as the base fabric,and polyurethane(PU)solution containing silica nanoparticles(PU@SiO_(2)NPs)was used as the coating solution to prepare composite tent fabric(PA/PU@SiO_(2)).The morphology,structure,and durability of the tent fabric under ultraviolet(UV)radiation,waterstained,or thermal conditions were investigated.The results show that compared with PA/PU fabric without SiO_(2)NPs,when the mass fraction of SiO_(2)NPs in PU coating is 5%,the air permeability of PA/PU@SiO_(2)fabric decreases from about 7.5 to 6.0 nm/s,while the reflectivity to UVvisible light is significantly improved.The surface wettability decreases,as indicated by the average water contact angle(WCA)on PA/PU@SiO_(2)remaining stable at 47°after 9 min.After thermal treatment,the PA/PU@SiO_(2)fabric shows superior mechanical stability.The degradation rate of the tensile strength is only 6.3%,approximately half that of the PA/PU fabric.Meanwhile,the elongation at break increases to 98.9%,compared to 61.8%for the PA/PU fabric.展开更多
文摘The exponential growth of audio data shared over the internet and communication channels has raised significant concerns about the security and privacy of transmitted information.Due to high processing requirements,traditional encryption algorithms demand considerable computational effort for real-time audio encryption.To address these challenges,this paper presents a permutation for secure audio encryption using a combination of Tent and 1D logistic maps.The audio data is first shuffled using Tent map for the random permutation.The high random secret key with a length equal to the size of the audio data is then generated using a 1D logistic map.Finally,the Exclusive OR(XOR)operation is applied between the generated key and the shuffled audio to yield the cipher audio.The experimental results prove that the proposed method surpassed the other techniques by encrypting two types of audio files,as mono and stereo audio files with large sizes up to 122 MB,different sample rates 22,050,44,100,48,000,and 96,000 for WAV and 44,100 sample rates for MP3 of size 11 MB.The results show high Mean Square Error(MSE),low Signal-to-Noise Ratio(SNR),spectral distortion,100%Number of Sample Change Rate(NSCR),high Percent Residual Deviation(PRD),low Correlation Coefficient(CC),large key space 2^(616),high sensitivity to a slight change in the secret key and that it can counter several attacks,namely brute force attack,statistical attack,differential attack,and noise attack.
文摘In this paper,polyamide(PA)woven fabric was used as the base fabric,and polyurethane(PU)solution containing silica nanoparticles(PU@SiO_(2)NPs)was used as the coating solution to prepare composite tent fabric(PA/PU@SiO_(2)).The morphology,structure,and durability of the tent fabric under ultraviolet(UV)radiation,waterstained,or thermal conditions were investigated.The results show that compared with PA/PU fabric without SiO_(2)NPs,when the mass fraction of SiO_(2)NPs in PU coating is 5%,the air permeability of PA/PU@SiO_(2)fabric decreases from about 7.5 to 6.0 nm/s,while the reflectivity to UVvisible light is significantly improved.The surface wettability decreases,as indicated by the average water contact angle(WCA)on PA/PU@SiO_(2)remaining stable at 47°after 9 min.After thermal treatment,the PA/PU@SiO_(2)fabric shows superior mechanical stability.The degradation rate of the tensile strength is only 6.3%,approximately half that of the PA/PU fabric.Meanwhile,the elongation at break increases to 98.9%,compared to 61.8%for the PA/PU fabric.
文摘万有引力搜索算法(gravitational search algorithm,GSA)相比于传统的优化算法具有收敛速度快、开拓性能强等特点,但GSA易陷入早熟收敛和局部最优,搜索能力较弱.为此,提出一种基于改进的Tent混沌万有引力搜索算法(gravitational search algorithm based on improved tent chaos,ITC-GSA).首先,改进Tent混沌映射来初始化种群,利用Tent混沌序列随机性、遍历性和规律性的特性使得初始种群随机性和遍历性在可行域内,具有加强算法的全局搜索能力;其次,引入引力常数G的动态调整策略提高算法的收敛速度和收敛精度;再次,设计成熟度指标判断种群成熟度,并使用Tent混沌搜索有效抑制算法早熟收敛,帮助种群跳出局部最优;最后,对10个基准函数进行仿真实验,结果表明所提算法能够有效克服GSA易陷入早熟收敛和局部最优的缺点,提高算法的收敛速度和寻优精度.