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The Cultural and Artistic Image of Modern China in the Perspective of Western Peregrinators
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作者 LI Chaojun 《Journal of Landscape Research》 2023年第4期53-56,共4页
Culture and art had always been the main field of western cognition of China.Since the middle and late 18th century,as Chinese civilization was on a downward trajectory,the image of oriental civilization with a long h... Culture and art had always been the main field of western cognition of China.Since the middle and late 18th century,as Chinese civilization was on a downward trajectory,the image of oriental civilization with a long history,prosperity,inclusiveness and harmony gradually disappeared,and“ancient”and“decline”became the main keywords to describe Chinese culture and art by western peregrinators. 展开更多
关键词 Peregrinator Cultural and artistic image image of China
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Estimation-free spatial-domain image reconstruction of structured illumination microscopy 被引量:1
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作者 Xiaoyan Li Shijie Tu +4 位作者 Yile Sun Yubing Han Xiang Hao Cuifang kuang Xu Liu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期45-58,共14页
Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditiona... Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditional Wiener-filtering-based reconstruction algorithm operates in the Fourier domain,it requires prior knowledge of the sinusoidal illumination patterns which makes the time-consuming procedure of parameter estimation to raw datasets necessary,besides,the parameter estimation is sensitive to noise or aberration-induced pattern distortion which leads to reconstruction artifacts.Here,we propose a spatial-domain image reconstruction method that does not require parameter estimation but calculates patterns from raw datasets,and a reconstructed image can be obtained just by calculating the spatial covariance of differential calculated patterns and differential filtered datasets(the notch filtering operation is performed to the raw datasets for attenuating and compensating the optical transfer function(OTF)).Experiments on reconstructing raw datasets including nonbiological,biological,and simulated samples demonstrate that our method has SR capability,high reconstruction speed,and high robustness to aberration and noise. 展开更多
关键词 Structured illumination microscopy image reconstruction spatial domain digital micromirror device(DMD)
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Wisdom of Spirit:The Heroic Images and Artistic Characteristics of The Old Man and The Sea 被引量:2
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作者 赵歆颖 《海外英语》 2010年第5X期219-221,共3页
The Old Man and The Sea is a masterpiece of the unyielding man:Hemingway.Being distinguished from many greatest American writers,Hemingway is noted for his writing style.Among all his works,The Old Man and the Sea is ... The Old Man and The Sea is a masterpiece of the unyielding man:Hemingway.Being distinguished from many greatest American writers,Hemingway is noted for his writing style.Among all his works,The Old Man and the Sea is a typical one which shows Hemingway's unique writing style and technique.The language is simple and natural on the surface,but actually deliberate and artificial.The heroic images of the old man are highly regarded by many writers and critics,the artistic characteristics of the novel make the work distinctive.This paper focuses mainly on the heroic images of the old man and artistic characteristics of the novel so as to help the readers get a better understanding of the work. 展开更多
关键词 Santiago HEROIC imageS artistic characteristics SPIRITUAL power
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RESEARCH ON KEY THECHNOLOGIES OF PORNOGRAPHIC IMAGE/VIDEO RECOGNITION IN COMPRESSED DOMAIN
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作者 Zhao Shiwei Zhuo Li Wang Suyu Shen Lansun 《Journal of Electronics(China)》 2009年第5期687-691,共5页
Pornographic image/video recognition plays a vital role in network information surveillance and management. In this paper, its key techniques, such as skin detection, key frame extraction, and classifier design, etc.,... Pornographic image/video recognition plays a vital role in network information surveillance and management. In this paper, its key techniques, such as skin detection, key frame extraction, and classifier design, etc., are studied in compressed domain. A skin detection method based on data-mining in compressed domain is proposed firstly and achieves the higher detection accuracy as well as higher speed. Then, a cascade scheme of pornographic image recognition based on selective decision tree ensemble is proposed in order to improve both the speed and accuracy of recognition. A pornographic video oriented key frame extraction solution in compressed domain and an approach of pornographic video recognition are discussed respectively in the end. 展开更多
关键词 视频识别 图像识别 压缩域 色情 关键帧提取 皮肤检测 分类器设计 信息监控
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Ghost imaging based on the control of light source bandwidth
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作者 刘兆骐 白艳锋 +3 位作者 邹璇彭凡 周立宇 付芹 傅喜泉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期276-279,共4页
A scheme to improve the quality in ghost imaging(GI)by controlling the bandwidth of light source(BCGI)is proposed.The theoretical and numerical results show that the reconstruction result with high quality can be obta... A scheme to improve the quality in ghost imaging(GI)by controlling the bandwidth of light source(BCGI)is proposed.The theoretical and numerical results show that the reconstruction result with high quality can be obtained by adjusting the bandwidth range of the light source appropriately,and the selection criterion of the bandwidth is analyzed by the power distribution of the imaging target.A proof-of-principle experiment is implemented to verify the theoretical and numerical results.In addition,the BCGI also presents better anti-noise performance when compared with some popular GI methods. 展开更多
关键词 ghost imaging light source property spatial frequency domain
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A Robust Zero-Watermarking Based on SIFT-DCT for Medical Images in the Encrypted Domain 被引量:5
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作者 Jialing Liu Jingbing Li +4 位作者 Yenwei Chen Xiangxi Zou Jieren Cheng Yanlin Liu Uzair Aslam Bhatti 《Computers, Materials & Continua》 SCIE EI 2019年第7期363-378,共16页
Remote medical diagnosis can be realized by using the Internet,but when transmitting medical images of patients through the Internet,personal information of patients may be leaked.Aim at the security of medical inform... Remote medical diagnosis can be realized by using the Internet,but when transmitting medical images of patients through the Internet,personal information of patients may be leaked.Aim at the security of medical information system and the protection of medical images,a novel robust zero-watermarking based on SIFT-DCT(Scale Invariant Feature Transform-Discrete Cosine Transform)for medical images in the encrypted domain is proposed.Firstly,the original medical image is encrypted in transform domain based on Logistic chaotic sequence to enhance the concealment of original medical images.Then,the SIFT-DCT is used to extract the feature sequences of encrypted medical images.Next,zero-watermarking technology is used to ensure that the region of interest of medical images are not changed.Finally,the robust of the algorithm is evaluated by the correlation coefficient between the original watermark and the attacked watermark.A series of attack experiments are carried out on this method,and the results show that the algorithm is not only secure,but also robust to both traditional and geometric attacks,especially in clipping attacks. 展开更多
关键词 ROBUSTNESS CT image ZERO-WATERMARKING SIFT-DCT encrypted domain
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A New Region-of-interest Coding Method to Control the Relative Quality of Progressive Decoded Images 被引量:2
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作者 李继良 方向忠 张冬冬 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第4期477-480,共4页
Based on the ideas of controlling relative quality and rearranging bitplanes, a new ROI coding method for JPEG2000 was proposed, which shifts and rearranges bitplanes in units of bitplane groups. It can code arbitrary... Based on the ideas of controlling relative quality and rearranging bitplanes, a new ROI coding method for JPEG2000 was proposed, which shifts and rearranges bitplanes in units of bitplane groups. It can code arbitrary shaped ROI without shape coding, and reserve almost arbitrary percent of background information. It also can control the relative quality of progressive decoded images. In addition, it is easy to be implemented and has low computational cost. 展开更多
关键词 region of INTEREST (ROI) image coding JPEG2000 transform domain
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A new approach for inversion of receiver function for crustal structure in the depth domain 被引量:2
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作者 TianYu Zheng YuMei He Yue Zhu 《Earth and Planetary Physics》 CSCD 2022年第1期83-95,共13页
A method for reconstructing crustal velocity structure using the optimization of stacking receiver function amplitude in the depth domain,named common conversion amplitude(CCA)inversion,is presented.The conversion amp... A method for reconstructing crustal velocity structure using the optimization of stacking receiver function amplitude in the depth domain,named common conversion amplitude(CCA)inversion,is presented.The conversion amplitude in the depth domain,which represents the impedance change in the medium,is obtained by assigning the receiver function amplitude to the corresponding conversion position where the P-to-S conversion occurred.Utilizing the conversion amplitude variation with depth as an optimization objective,imposing reliable prior constraints on the structural model frame and velocity range,and adopting a stepwise search inversion technique,this method efficiently weakens the tendency of easily falling into the local extremum in conventional receiver function inversion.Synthetic tests show that the CCA inversion can reconstruct complex crustal velocity structures well and is especially suitable for revealing crustal evolution by estimating diverse velocity distributions.Its performance in reconstructing crustal structure is superior to that of the conventional receiver function imaging method. 展开更多
关键词 crustal imaging receiver function depth domain INVERSION
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From the Gla domain to a novel small-molecule detector of apoptosis 被引量:12
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作者 Avi Cohen Anat Shirvan Galit Levin Hagit Grimberg Ayelet Reshef Ilan Ziv 《Cell Research》 SCIE CAS CSCD 2009年第5期625-637,共13页
Apoptosis 在众多的医药混乱的病原学或致病起一个枢轴的作用,并且这样, apoptotic 房间指向可以实质地推进耐心的照顾。在我们为为 apoptosis 的新奇 low-molecular-weight 探针的探索,我们集中了于不平常的氨基酸纬 - carboxygluta... Apoptosis 在众多的医药混乱的病原学或致病起一个枢轴的作用,并且这样, apoptotic 房间指向可以实质地推进耐心的照顾。在我们为为 apoptosis 的新奇 low-molecular-weight 探针的探索,我们集中了于不平常的氨基酸纬 - carboxyglutamic 酸(Gla ) ,它在 clotting 因素的绑定起一个重要作用到否定地控告的 phospholipid 表面。基于 Gla 的 alkyl-malonic 酸主题,我们开发了并且现在介绍 ML-10 (2-(5-fluoro-pentyl )-2-methyl-malonic 酸, MW=206 Da ) , apoptosis 的小分子的察觉者的一个新奇家庭的原型的成员。ML-10 被发现在 apoptotic 房间执行选择举起和累积,当从可行或坏死的房间被排除时。有 caspase 激活, Annexin-V 绑定和 mitochondrial 膜潜力的混乱的 apoptotic 特点的 ML-10 举起相互关联。malonate 一半被发现为在 apoptosis 察觉的 ML-10 功能关键。ML-10 在早 apoptosis 对房间的特征的唯一的建筑群作出回应,包括膜潜力,房间膜和细胞质的永久使发酸,和膜正直的保藏的不可逆的损失。ML-10 因此是迄今为止知道的最紧缩的 apoptosis 探查。由于它的氟的符号原子, ML-10 对顺从与 18F 同位素标记收音机,向它为 apoptosis 的临床的正电子排放断层摄影术成像的潜在的未来使用。 展开更多
关键词 细胞凋亡 分子检测 谷氨酸 线粒体膜电位 CASPASES 选择性吸收 不可逆损失 正电子发射
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Spectroscopic measurements and terahertz imaging of the cornea using a rapid scanning terahertz time domain spectrometer
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作者 刘文权 鲁远甫 +7 位作者 焦国华 陈险峰 周志盛 佘荣斌 李金瑛 陈四海 董玉明 吕建成 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期150-156,共7页
Spectroscopic measurements and terahertz imaging of the cornea are carried out by using a rapid scanning terahertz time domain spectroscopy(THz-TDS) system.A voice coil motor stage based optical delay line(VCM-ODL... Spectroscopic measurements and terahertz imaging of the cornea are carried out by using a rapid scanning terahertz time domain spectroscopy(THz-TDS) system.A voice coil motor stage based optical delay line(VCM-ODL) is developed to provide a rather simple and robust structure with both the high scanning speed and the large delay length.The developed system is used for THz spectroscopic measurements and imaging of the corneal tissue with different amounts of water content,and the measurement results show the consistence with the reported results,in which the measurement time using VCM-ODL is a factor of 360 shorter than the traditional motorized optical delay line(MDL).With reducing the water content a monotonic decrease of the complex permittivity of the cornea is observed.The two-term Debye relaxation model is employed to explain our experimental results,revealing that the fast relaxation time of a dehydrated cornea is much larger than that of a hydrated cornea and its dielectric behavior can be affected by the presence of the biological macromolecules.These results demonstrate that our THz spectrometer may be a promising candidate for tissue hydration sensing and practical application of THz technology. 展开更多
关键词 TERAHERTZ rapid scanning terahertz time domain spectrometer tissue diagnostics terahertz imaging
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Watermarking Images in the Frequency Domain by Exploiting Self-Inverting Permutations
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作者 Maria Chroni Angelos Fylakis Stavros D. Nikolopoulos 《Journal of Information Security》 2013年第2期80-91,共12页
In this work we propose efficient codec algorithms for watermarking images that are intended for uploading on the web under intellectual property protection. Headed to this direction, we recently suggested a way in wh... In this work we propose efficient codec algorithms for watermarking images that are intended for uploading on the web under intellectual property protection. Headed to this direction, we recently suggested a way in which an integer number w which being transformed into a self-inverting permutation, can be represented in a two dimensional (2D) object and thus, since images are 2D structures, we have proposed a watermarking algorithm that embeds marks on them using the 2D representation of w in the spatial domain. Based on the idea behind this technique, we now expand the usage of this concept by marking the image in the frequency domain. In particular, we propose a watermarking technique that also uses the 2D representation of self-inverting permutations and utilizes marking at specific areas thanks to partial modifications of the image’s Discrete Fourier Transform (DFT). Those modifications are made on the magnitude of specific frequency bands and they are the least possible additive information ensuring robustness and imperceptiveness. We have experimentally evaluated our algorithms using various images of different characteristics under JPEG compression. The experimental results show an improvement in comparison to the previously obtained results and they also depict the validity of our proposed codec algorithms. 展开更多
关键词 WATERMARKING Techniques image WATERMARKING Algorithms Self-Inverting PERMUTATIONS 2D REPRESENTATIONS of PERMUTATIONS ENCODING DECODING Frequency domain Experimental Evaluation
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3D Gravity Inversion with Correlation Image in Space Domain and Application to the Northern Sinai Peninsula
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作者 Xu Zhang Peng Yu Jian Wang 《Journal of Geological Research》 2019年第2期9-18,共10页
We present a 3D inversion method to recover density distribution from gravity data in space domain.Our method firstly employs 3D correlation image of the vertical gradient of gravity data as a starting model to genera... We present a 3D inversion method to recover density distribution from gravity data in space domain.Our method firstly employs 3D correlation image of the vertical gradient of gravity data as a starting model to generate a higher resolution image for inversion.The 3D density distribution is then obtained by inverting the correlation image of gravity data to fit the observed data based on classical inversion method of the steepest descent method.We also perform the effective equivalent storage and subdomain techniques in the starting model calculation,the forward modeling and the inversion procedures,which allow fast computation in space domain with reducing memory consumption but maintaining accuracy.The efficiency and stability of our method is demonstrated on two sets of synthetic data and one set of the Northern Sinai Peninsula gravity data.The inverted 3D density distributions show that high density bodies beneath Risan Aniza and low density bodies exist to the southeast of Risan Aniza at depths between 1~10 and 20 km,which may be originated from hot anomalies in the lower crust.The results show that our inversion method is useful for 3D quantitative interpretation. 展开更多
关键词 3D gravity inversion Space domain Correlation image Effective equivalent storage Subdomain technique Northern Sinai Peninsula
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The Implementation of Mirror-Image Effect in MPEG-2 Compressed Video
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作者 倪强 周磊 张文军 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期151-156,共6页
Straightforward techniques for spatial domain digital video editing (DVE) of compressed video via decompression and recompression are computationally expensive. In this paper, a novel algorithm was proposed for mirror... Straightforward techniques for spatial domain digital video editing (DVE) of compressed video via decompression and recompression are computationally expensive. In this paper, a novel algorithm was proposed for mirror-image special effect editing in compressed video without full frame decompression and motion estimation. The results show that with the reducing of computational complexity, the quality of edited video in compressed domain is still close to the quality of the edited video in uncompressed domain at the same bit rate. 展开更多
关键词 数字视频编辑 压缩域 MPEG-2 镜像 DCT 特技效果
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Robust zero-watermarking algorithm based on discrete wavelet transform and daisy descriptors for encrypted medical image
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作者 Yiyi Yuan Jingbing Li +3 位作者 Jing Liu Uzair Aslam Bhatti Zilong Liu Yen-wei Chen 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第1期40-53,共14页
In the intricate network environment,the secure transmission of medical images faces challenges such as information leakage and malicious tampering,significantly impacting the accuracy of disease diagnoses by medical ... In the intricate network environment,the secure transmission of medical images faces challenges such as information leakage and malicious tampering,significantly impacting the accuracy of disease diagnoses by medical professionals.To address this problem,the authors propose a robust feature watermarking algorithm for encrypted medical images based on multi-stage discrete wavelet transform(DWT),Daisy descriptor,and discrete cosine transform(DCT).The algorithm initially encrypts the original medical image through DWT-DCT and Logistic mapping.Subsequently,a 3-stage DWT transformation is applied to the encrypted medical image,with the centre point of the LL3 sub-band within its low-frequency component serving as the sampling point.The Daisy descriptor matrix for this point is then computed.Finally,a DCT transformation is performed on the Daisy descriptor matrix,and the low-frequency portion is processed using the perceptual hashing algorithm to generate a 32-bit binary feature vector for the medical image.This scheme utilises cryptographic knowledge and zero-watermarking technique to embed watermarks without modifying medical images and can extract the watermark from test images without the original image,which meets the basic re-quirements of medical image watermarking.The embedding and extraction of water-marks are accomplished in a mere 0.160 and 0.411s,respectively,with minimal computational overhead.Simulation results demonstrate the robustness of the algorithm against both conventional attacks and geometric attacks,with a notable performance in resisting rotation attacks. 展开更多
关键词 daisy descriptor DCT DWT encryption domain medical image ZERO-WATERMARKING
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Image Fusion Using Wavelet Transformation and XGboost Algorithm
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作者 Shahid Naseem Tariq Mahmood +4 位作者 Amjad Rehman Khan Umer Farooq Samra Nawazish Faten S.Alamri Tanzila Saba 《Computers, Materials & Continua》 SCIE EI 2024年第4期801-817,共17页
Recently,there have been several uses for digital image processing.Image fusion has become a prominent application in the domain of imaging processing.To create one final image that provesmore informative and helpful ... Recently,there have been several uses for digital image processing.Image fusion has become a prominent application in the domain of imaging processing.To create one final image that provesmore informative and helpful compared to the original input images,image fusion merges two or more initial images of the same item.Image fusion aims to produce,enhance,and transform significant elements of the source images into combined images for the sake of human visual perception.Image fusion is commonly employed for feature extraction in smart robots,clinical imaging,audiovisual camera integration,manufacturing process monitoring,electronic circuit design,advanced device diagnostics,and intelligent assembly line robots,with image quality varying depending on application.The research paper presents various methods for merging images in spatial and frequency domains,including a blend of stable and curvelet transformations,everageMax-Min,weighted principal component analysis(PCA),HIS(Hue,Intensity,Saturation),wavelet transform,discrete cosine transform(DCT),dual-tree Complex Wavelet Transform(CWT),and multiple wavelet transform.Image fusion methods integrate data from several source images of an identical target,thereby enhancing information in an extremely efficient manner.More precisely,in imaging techniques,the depth of field constraint precludes images from focusing on every object,leading to the exclusion of certain characteristics.To tackle thess challanges,a very efficient multi-focus wavelet decomposition and recompositionmethod is proposed.The use of these wavelet decomposition and recomposition techniques enables this method to make use of existing optimized wavelet code and filter choice.The simulated outcomes provide evidence that the suggested approach initially extracts particular characteristics from images in order to accurately reflect the level of clarity portrayed in the original images.This study enhances the performance of the eXtreme Gradient Boosting(XGBoost)algorithm in detecting brain malignancies with greater precision through the integration of computational image analysis and feature selection.The performance of images is improved by segmenting them employing the K-Means algorithm.The segmentation method aids in identifying specific regions of interest,using Particle Swarm Optimization(PCA)for trait selection and XGBoost for data classification.Extensive trials confirm the model’s exceptional visual performance,achieving an accuracy of up to 97.067%and providing good objective indicators. 展开更多
关键词 image fusion max-min average CWT XGBoost DCT inclusive innovations spatial and frequency domain
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A chaotic hierarchical encryption/watermark embedding scheme for multi-medical images based on row-column confusion and closed-loop bi-directional diffusion
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作者 张哲祎 牟俊 +1 位作者 Santo Banerjee 曹颖鸿 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期228-237,共10页
Security during remote transmission has been an important concern for researchers in recent years.In this paper,a hierarchical encryption multi-image encryption scheme for people with different security levels is desi... Security during remote transmission has been an important concern for researchers in recent years.In this paper,a hierarchical encryption multi-image encryption scheme for people with different security levels is designed,and a multiimage encryption(MIE)algorithm with row and column confusion and closed-loop bi-directional diffusion is adopted in the paper.While ensuring secure communication of medical image information,people with different security levels have different levels of decryption keys,and differentiated visual effects can be obtained by using the strong sensitivity of chaotic keys.The highest security level can obtain decrypted images without watermarks,and at the same time,patient information and copyright attribution can be verified by obtaining watermark images.The experimental results show that the scheme is sufficiently secure as an MIE scheme with visualized differences and the encryption and decryption efficiency is significantly improved compared to other works. 展开更多
关键词 chaotic hierarchical encryption multi-medical image encryption differentiated visual effects row-column confusion closed-loop bi-directional diffusion transform domain watermark embedding
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Three-dimensional quantication of protoporphyrin IX in photodynamic therapy using SFDI/DFT:A pilot experimental validation
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作者 Mai Dan Weijie Song +2 位作者 Meihui Liu Yaru Zhang Feng Gao 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2022年第6期30-39,共10页
Photodynamic therapy(PDT)dosimetry,induding light dose,photosensitizer dose and tissue oxygen,has been a research focus in PDT.In this work,we present a three-dimensional(3D)quantification of protoporphyrin X(PpIX)usi... Photodynamic therapy(PDT)dosimetry,induding light dose,photosensitizer dose and tissue oxygen,has been a research focus in PDT.In this work,we present a three-dimensional(3D)quantification of protoporphyrin X(PpIX)using combined spatial frequency domain imaging(SFDI)and diffuse fuorescence tomography(DFT).The SFDI maps both the distributions of tissue absorption and scattering properties at three wavelengths and accordingly provides the optical background for DFT and extracts the tissue oxygenation for assessing the therapeutic outcomes,while DFT dynamically monitors the 3D distribution of PpEX dose from measured fluorescence signals for the procedure optimization.A pilot in vrivo application in tumor nude models showed that the proposed SFDI/DFT is able to dynamically trace changes in the PpX concentration and tissue oaxygen during the treatment,rendering it a potentially powerful tool for PDT to improve clinical eficacy. 展开更多
关键词 Photodynamic therapy spatial frequency domain imaging difuse fuorescence tomography
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SDOCT IMAGE RECONSTRUCTION BY INTERFEROMETRIC SYNTHETIC APERTURE MICROSCOPY
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作者 XIAODONG CHEN QIAO LI +2 位作者 YONG LEI YI WANG DAOYIN YU 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2010年第1期17-23,共7页
Spectral domain optical coherence tomography(SDOCT)is a noninvasive,cross-sectional imaging technique that measures depth resolved reflectance of tissue by Fourier transforming the spectral interferogram with the scan... Spectral domain optical coherence tomography(SDOCT)is a noninvasive,cross-sectional imaging technique that measures depth resolved reflectance of tissue by Fourier transforming the spectral interferogram with the scanning of the reference avoided.Interferometric synthetic aperture microscopy(ISAM)is an optical microscopy computed-imaging technique for measuring the optical properties of biological tissues,which can overcome the compromise between depth of focus and transverse resolution.This paper describes the principle of SDOCT and ISAM,which multiplexes raw acquisitions to provide quantitatively meaningful data with reliable spatially invariant resolution at all depths.A mathematical model for a coherent microscope with a planar scanning geometry and spectral detection was described.The two-dimensional fast Fourier transform(FFT)of spectral data in the transverse directions was calculated.Then the nonuniform ISAM resampling and filtering was implemented to yield the scattering potential within the scalar model.Inverse FFT was used to obtain the ISAM reconstruction.One scatterer,multiple scatterers,and noisy simulations were implemented by use of ISAM to catch spatially invariant resolution.ISAM images were compared to those obtained using standard optical coherence tomography(OCT)methods.The high quality of the results validates the rationality of the founded model and that diffraction limited resolution can be achieved outside the focal plane. 展开更多
关键词 Optical coherence tomography(OCT) spectral domain OCT(SDOCT) interferometric synthetic aperture microscopy(ISAM) resolution image reconstruction
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A multiple watermarks algorithm for image content authentication
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作者 蔡立军 李睿 易叶青 《Journal of Central South University》 SCIE EI CAS 2012年第10期2866-2874,共9页
A novel multiple watermarks cooperative authentication algorithm was presented for image contents authentication.This algorithm is able to extract multiple features from the image wavelet domain,which is based on that... A novel multiple watermarks cooperative authentication algorithm was presented for image contents authentication.This algorithm is able to extract multiple features from the image wavelet domain,which is based on that the t watermarks are generated.Moreover,a new watermark embedding method,using the space geometric model,was proposed,in order to effectively tackle with the mutual influences problem among t watermarks.Specifically,the incidental tampering location,the classification of intentional content tampering and the incidental modification can be achieved via mutual cooperation of the t watermarks.Both the theoretical analysis and simulations results validate the feasibility and efficacy of the proposed algorithm. 展开更多
关键词 图像内容认证 水印算法 水印嵌入方法 空间几何模型 认证算法 仿真结果 小波域 合作
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Nanocrystalline and Nanocomposite Magnetic Materials and Their Applications 被引量:2
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作者 Robert D Shull 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2007年第4期69-74,共6页
Nanocrystalline materials can possess bulk properties quite different from those commonly associated with conventional large-grained materials. Nanocomposites, a subset of nanocrystalline materials, in addition have b... Nanocrystalline materials can possess bulk properties quite different from those commonly associated with conventional large-grained materials. Nanocomposites, a subset of nanocrystalline materials, in addition have been found to possess magnetic properties which are similar to, but different from, the properties of the individual constituents. New magnetic phenomena, unusual property combinations, and both enhanced and diminished magnetic property values are just some of the changes observed in magnetic nanocomposites from conventional magnetic materials. Here, a description will be presented of some of the exciting new properties discovered in nanomaterials and the magnetic applications envisioned for them. 展开更多
关键词 NANOCOMPOSITE FERROMAGNET MAGNETORESISTANCE magnetic refrigeration domain imaging
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