In telemedicine,the realization of reversible watermarking through information security is an emerging research field.However,adding watermarks hinders the distribution of pixels in the cover image because it creates ...In telemedicine,the realization of reversible watermarking through information security is an emerging research field.However,adding watermarks hinders the distribution of pixels in the cover image because it creates distortions(which lead to an increase in the detection probability).In this article,we introduce a reversible watermarking method that can transmit medical images with minimal distortion and high security.The proposed method selects two adjacent gray pixels whose least significant bit(LSB)is different from the relevant message bit and then calculates the distortion degree.We use the LSB pairing method to embed the secret matrix of patient record into the cover image and exchange pixel values.Experimental results show that the designed method is robust to different attacks and has a high PSNR(peak signal-to-noise ratio)value.The MRI image quality and imperceptibility are verified by embedding a secret matrix of up to 262,688 bits to achieve an average PSNR of 51.657 dB.In addition,the proposed algorithm is tested against the latest technology on standard images,and it is found that the average PSNR of our proposed reversible watermarking technology is higher(i.e.,51.71 dB).Numerical results show that the algorithm can be extended to normal images and medical images.展开更多
The authenticity and integrity of healthcare is the primary objective.Numerous reversible watermarking schemes have been developed to improve the primary objective but increasing the quantity of embedding data leads t...The authenticity and integrity of healthcare is the primary objective.Numerous reversible watermarking schemes have been developed to improve the primary objective but increasing the quantity of embedding data leads to covering image distortion and visual quality resulting in data security detection.A trade-off between robustness,imperceptibility,and embedded capacity is difficult to achieve with current algorithms due to limitations in their ability.Keeping this purpose insight,an improved reversibility watermarking methodology is proposed to maximize data embedding capacity and imperceptibility while maintaining data security as a primary concern.A key is generated by a random path with minimum bit flipping is selected in the 4 × 4 block to gain access to the data embedding patterns.The random path's complex structure ensures data security.Data of various sizes(8 KB,16 KB,32 KB)are used to analyze image imperceptibility and evaluate quality factors.The proposed reversible watermarking methodology performance is tested under standard structures PSNR,SSIM,and MSE.The results revealed that the MRI watermarked images are imperceptible,like the cover image when LSB is 3 bits plane.Our proposed reversible watermarking methodology outperforms other related techniques in terms of average PSNR(49.29).Experiment results show that the suggested reversible watermarking method improves data embedding capacity and imperceptibility compared to existing state-of-the-art approaches.展开更多
Sentiment analysis depends on individuals’comments and opinions on events.Data from social media platforms like Twitter,Quora,or Facebook poses challenges due to informal language,including acronyms,misspellings,and ...Sentiment analysis depends on individuals’comments and opinions on events.Data from social media platforms like Twitter,Quora,or Facebook poses challenges due to informal language,including acronyms,misspellings,and ambiguous terms.Additionally,hyperparameters in machine learning models significantly impact performance.To address these issues,we propose advanced feature engineering techniques in Natural Language Processing(NLP)and hyperparameter optimization to enhance prediction accuracy and generalization capabilities.Our study employs Naïve Bayes,Logistic Regression(LR),Multi-layer Perceptron(MLP),and Support Vector Machine(SVM)to classify sentiments in tweets about Elon Musk’s potential acquisition of Twitter.The dataset,consisting of 100,000 tweets,is fetched using the Twitter representational state transfer application programming interface(REST API).We outline a sentiment analysis procedure to classify unstructured Twitter data,identify influential keywords,and categorize sentiments as Positive,Negative,or Neutral.Using a hybrid Lexicon NLP approach,we extract contextually significant emotionally charged words and assign sentiment polarities.Hyperparameter optimization via automated search methods ensures alignment with classifier performance estimates.SVM achieved an impressive accuracy rate of 97%.Cross-validation minimizes random variations,providing a reliable assessment of the model’s generalization capabilities,and demonstrating the method’s accuracy in predicting sentiments with larger new unseen standard datasets,and varying sentiment.展开更多
Metasurface,a forefront in emerging optical devices,has demonstrated remarkable potential for complex amplitude manipulation of light beams.However,prevailing approaches face challenges in spatial resolution and compl...Metasurface,a forefront in emerging optical devices,has demonstrated remarkable potential for complex amplitude manipulation of light beams.However,prevailing approaches face challenges in spatial resolution and complexities associated with integrating dynamic phases,impeding the simplified design and reproducible fabrication of metasurfaces.Here,we introduce an innovative approach for complex amplitude modulation within 3D nano-printed geometric phase metasurfaces.Our approach enables the generation of self-accelerating beams by encoding amplitude through phase-only manipulation,achieving high spatial resolution.Notably,this method circumvents the conventional need to adjust the geometric parameters of metasurface unit structures for amplitude manipulation,offering a streamlined and efficient route for design and fabrication complexity.This novel methodology holds promise for expedited and low-cost manufacturing of complex amplitude manipulation metasurfaces.展开更多
A method is presented for one-to-many information encryption transmission by using temporal ghost imaging and code division multiple access.In the encryption transmission process,code division multiple access technolo...A method is presented for one-to-many information encryption transmission by using temporal ghost imaging and code division multiple access.In the encryption transmission process,code division multiple access technologies combine multiple information sources,and the chip sequence corresponding to each set of information is used as the first key.The transmission end loads the transmission information onto a series of temporal random patterns of temporal ghost imaging and transmits it to the receivers.A series of temporal random patterns is the second key.During the decryption,each receiver can get the same encrypted information and use the second key to obtain the transmitted information.Finally,each receiver uses the unique chip sequence to get corresponding information.This encryption transmission method realizes one-to-many information encryption transmission at the same time over the same channel.Double encryption ensures the security of information.Simulation and experiment results verify the effectiveness and security of the method.The method has strong antinoise ability and can effectively resist various attack modes.At the same time,this method solves the problem that the use of code division multiple access enlarges the signal bandwidth,and ensures that no cross talk occurs between various sources of information.展开更多
Airy optical beams have emerged to hold enormous theoretical and experimental research interest due to their outstanding characteristics.Conventional approaches suffer from bulky and costly systems,as well as poor pha...Airy optical beams have emerged to hold enormous theoretical and experimental research interest due to their outstanding characteristics.Conventional approaches suffer from bulky and costly systems,as well as poor phase discretization.The newly developed metasurface-based Airy beam generators have constraints of polarization dependence or limited generation efficiency.Here,we experimentally demonstrate a polarization-independent silicon dielectric metasurface for generation of high-efficiency Airy optical beams.In our implementation,rather than synchronous manipulation of the amplitude and phase by plasmonic or Huygens’metasurfaces,we employ and impose a 3/2 phase-only manipulation to the dielectric metasurface,consisting of an array of silicon nanopillars with an optimized transmission efficiency as high as 97%.The resultant Airy optical beams possess extraordinarily large deflection angles and relatively narrow beam widths.Our validated scheme will open up a fascinating doorway to broaden the application scenarios of Airy optical beams on ultracompact photonic platforms.展开更多
基金This work is supported by the National Natural Science Foundation of China(Grant 61762060)Educational Commission of Gansu Province,China(Grant 2017C-05)Foundation for the Key Research and Development Program of Gansu Province,China(Grant 20YF3GA016).
文摘In telemedicine,the realization of reversible watermarking through information security is an emerging research field.However,adding watermarks hinders the distribution of pixels in the cover image because it creates distortions(which lead to an increase in the detection probability).In this article,we introduce a reversible watermarking method that can transmit medical images with minimal distortion and high security.The proposed method selects two adjacent gray pixels whose least significant bit(LSB)is different from the relevant message bit and then calculates the distortion degree.We use the LSB pairing method to embed the secret matrix of patient record into the cover image and exchange pixel values.Experimental results show that the designed method is robust to different attacks and has a high PSNR(peak signal-to-noise ratio)value.The MRI image quality and imperceptibility are verified by embedding a secret matrix of up to 262,688 bits to achieve an average PSNR of 51.657 dB.In addition,the proposed algorithm is tested against the latest technology on standard images,and it is found that the average PSNR of our proposed reversible watermarking technology is higher(i.e.,51.71 dB).Numerical results show that the algorithm can be extended to normal images and medical images.
基金supported by the National Natural Science Foundation of China(Grant No.61762060)Educational Commission of Gansu Province,China(Grant No.2017C-05)+2 种基金Foundation for the Key Research and Development Program of Gansu Province,China(Grant No.20YF3GA016)supported by King Saud University,Riyadh,Saudi Arabia,through Researchers Supporting Project No.RSP-2022/184The work of author Ayman Radwan was supported by FCT/MEC through Programa Operacional Regional do Centro and by the European Union through the European Social Fund(ESF)under Investigator FCT Grant(5G-AHEAD IF/FCT-IF/01393/2015/CP1310/CT0002).
文摘The authenticity and integrity of healthcare is the primary objective.Numerous reversible watermarking schemes have been developed to improve the primary objective but increasing the quantity of embedding data leads to covering image distortion and visual quality resulting in data security detection.A trade-off between robustness,imperceptibility,and embedded capacity is difficult to achieve with current algorithms due to limitations in their ability.Keeping this purpose insight,an improved reversibility watermarking methodology is proposed to maximize data embedding capacity and imperceptibility while maintaining data security as a primary concern.A key is generated by a random path with minimum bit flipping is selected in the 4 × 4 block to gain access to the data embedding patterns.The random path's complex structure ensures data security.Data of various sizes(8 KB,16 KB,32 KB)are used to analyze image imperceptibility and evaluate quality factors.The proposed reversible watermarking methodology performance is tested under standard structures PSNR,SSIM,and MSE.The results revealed that the MRI watermarked images are imperceptible,like the cover image when LSB is 3 bits plane.Our proposed reversible watermarking methodology outperforms other related techniques in terms of average PSNR(49.29).Experiment results show that the suggested reversible watermarking method improves data embedding capacity and imperceptibility compared to existing state-of-the-art approaches.
基金supported by the National Key R&D Program of China(2018YFA0701800)the National Natural Science Foundation of China(NSFC,project no.62175153).
文摘Sentiment analysis depends on individuals’comments and opinions on events.Data from social media platforms like Twitter,Quora,or Facebook poses challenges due to informal language,including acronyms,misspellings,and ambiguous terms.Additionally,hyperparameters in machine learning models significantly impact performance.To address these issues,we propose advanced feature engineering techniques in Natural Language Processing(NLP)and hyperparameter optimization to enhance prediction accuracy and generalization capabilities.Our study employs Naïve Bayes,Logistic Regression(LR),Multi-layer Perceptron(MLP),and Support Vector Machine(SVM)to classify sentiments in tweets about Elon Musk’s potential acquisition of Twitter.The dataset,consisting of 100,000 tweets,is fetched using the Twitter representational state transfer application programming interface(REST API).We outline a sentiment analysis procedure to classify unstructured Twitter data,identify influential keywords,and categorize sentiments as Positive,Negative,or Neutral.Using a hybrid Lexicon NLP approach,we extract contextually significant emotionally charged words and assign sentiment polarities.Hyperparameter optimization via automated search methods ensures alignment with classifier performance estimates.SVM achieved an impressive accuracy rate of 97%.Cross-validation minimizes random variations,providing a reliable assessment of the model’s generalization capabilities,and demonstrating the method’s accuracy in predicting sentiments with larger new unseen standard datasets,and varying sentiment.
基金supported by the National Natural Science Foundation of China(Grant No.62175153)the National Key R&D Program of China(Grant No.2018YFA0701800)。
文摘Metasurface,a forefront in emerging optical devices,has demonstrated remarkable potential for complex amplitude manipulation of light beams.However,prevailing approaches face challenges in spatial resolution and complexities associated with integrating dynamic phases,impeding the simplified design and reproducible fabrication of metasurfaces.Here,we introduce an innovative approach for complex amplitude modulation within 3D nano-printed geometric phase metasurfaces.Our approach enables the generation of self-accelerating beams by encoding amplitude through phase-only manipulation,achieving high spatial resolution.Notably,this method circumvents the conventional need to adjust the geometric parameters of metasurface unit structures for amplitude manipulation,offering a streamlined and efficient route for design and fabrication complexity.This novel methodology holds promise for expedited and low-cost manufacturing of complex amplitude manipulation metasurfaces.
基金Natural Science Foundation of Shanghai(18ZR1425800)Anhui Province Key Laboratory of Nondestructive Evaluation(CGHBMWSJC03)National Natural Science Foundation of China(61775140,61875125)
文摘A method is presented for one-to-many information encryption transmission by using temporal ghost imaging and code division multiple access.In the encryption transmission process,code division multiple access technologies combine multiple information sources,and the chip sequence corresponding to each set of information is used as the first key.The transmission end loads the transmission information onto a series of temporal random patterns of temporal ghost imaging and transmits it to the receivers.A series of temporal random patterns is the second key.During the decryption,each receiver can get the same encrypted information and use the second key to obtain the transmitted information.Finally,each receiver uses the unique chip sequence to get corresponding information.This encryption transmission method realizes one-to-many information encryption transmission at the same time over the same channel.Double encryption ensures the security of information.Simulation and experiment results verify the effectiveness and security of the method.The method has strong antinoise ability and can effectively resist various attack modes.At the same time,this method solves the problem that the use of code division multiple access enlarges the signal bandwidth,and ensures that no cross talk occurs between various sources of information.
基金National Natural Science Foundation of China(61775140,81701745)National Key Research and Development Program of China(2018YFA0701800)+1 种基金Shanghai Municipal Science and Technology Commission Innovation Action Plan(18DZ1100400)City University of Hong Kong(9610456)。
文摘Airy optical beams have emerged to hold enormous theoretical and experimental research interest due to their outstanding characteristics.Conventional approaches suffer from bulky and costly systems,as well as poor phase discretization.The newly developed metasurface-based Airy beam generators have constraints of polarization dependence or limited generation efficiency.Here,we experimentally demonstrate a polarization-independent silicon dielectric metasurface for generation of high-efficiency Airy optical beams.In our implementation,rather than synchronous manipulation of the amplitude and phase by plasmonic or Huygens’metasurfaces,we employ and impose a 3/2 phase-only manipulation to the dielectric metasurface,consisting of an array of silicon nanopillars with an optimized transmission efficiency as high as 97%.The resultant Airy optical beams possess extraordinarily large deflection angles and relatively narrow beam widths.Our validated scheme will open up a fascinating doorway to broaden the application scenarios of Airy optical beams on ultracompact photonic platforms.