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Practice and Effect of Appropriate Error-correction in English Teaching 被引量:2
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作者 任静明 胡蓉 《Journal of Donghua University(English Edition)》 EI CAS 2002年第2期140-142,共3页
This paper points out that with interference from their native language and culture, Chinese students will inevitably make some errors in the process of learning English. It is important for teachers to know when and ... This paper points out that with interference from their native language and culture, Chinese students will inevitably make some errors in the process of learning English. It is important for teachers to know when and how to correct the students’ errors. By employing error-correction skillfully and appropriately, one can expect to improve the present English teaching and learning, to develop the self-confidence and self-esteem in students themselves. 展开更多
关键词 error-correction practice EFFECT
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A Quantum Error-Correction Circuit Based on Cyclic Code
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作者 Lü Hongjun ZHANG Zhike XIE Guangjun 《Wuhan University Journal of Natural Sciences》 CAS 2013年第5期413-417,共5页
In this paper, the cyclic code of the classic circuit is transformed and transplanted; then, the quantum encoding scheme based on cyclic code and quantum error-correction circuit is constructed. The proposed circuit c... In this paper, the cyclic code of the classic circuit is transformed and transplanted; then, the quantum encoding scheme based on cyclic code and quantum error-correction circuit is constructed. The proposed circuit can correct one-bit error, and the use of redundant bits to encode more than one-bit quantum information breaks the previous limitations of many bits encoding a quantum bit. Compared with the existing coding circuits (Shor code, Steane code and five stable subcode), it shows obvious superiority in the quantum coding efficiency and transmission efficiency. 展开更多
关键词 quantum information quantum error-correction code cyclic code redundant bit
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Enhancement of Error-Correction Coding of Spatial Watermarks in Gray Code
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作者 Tadahiko Kimoto 《Journal of Signal and Information Processing》 2013年第1期57-63,共7页
This paper demonstrates how channel coding can improve the robustness of spatial image watermarks against signal distortion caused by lossy data compression such as the JPEG scheme by taking advantage of the propertie... This paper demonstrates how channel coding can improve the robustness of spatial image watermarks against signal distortion caused by lossy data compression such as the JPEG scheme by taking advantage of the properties of Gray code. Two error-correction coding (ECC) schemes are used here: One scheme, referred to as the vertical ECC (VECC), is to encode information bits in a pixel by error-correction coding where the Gray code is used to improve the performance. The other scheme, referred to as the horizontal ECC (HECC), is to encode information bits in an image plane. In watermarking, HECC generates a codeword representing watermark bits, and each bit of the codeword is encoded by VECC. Simple single-error-correcting block codes are used in VECC and HECC. Several experiments of these schemes were conducted on test images. The result demonstrates that the error-correcting performance of HECC just depends on that of VECC, and accordingly, HECC enhances the capability of VECC. Consequently, HECC with appropriate codes can achieve stronger robustness to JPEG—caused distortions than non-channel-coding watermarking schemes. 展开更多
关键词 error-correction Coding GRAY Code Digital WATERMARK SPATIAL Domain JPEG DCT Compression
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Spatial Image Watermarking by Error-Correction Coding in Gray Codes
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作者 Tadahiko Kimoto 《Journal of Signal and Information Processing》 2013年第3期259-273,共15页
In this paper, error-correction coding (ECC) in Gray codes is considered and its performance in the protecting of spatial image watermarks against lossy data compression is demonstrated. For this purpose, the differen... In this paper, error-correction coding (ECC) in Gray codes is considered and its performance in the protecting of spatial image watermarks against lossy data compression is demonstrated. For this purpose, the differences between bit patterns of two Gray codewords are analyzed in detail. On the basis of the properties, a method for encoding watermark bits in the Gray codewords that represent signal levels by a single-error-correcting (SEC) code is developed, which is referred to as the Gray-ECC method in this paper. The two codewords of the SEC code corresponding to respective watermark bits are determined so as to minimize the expected amount of distortion caused by the watermark embedding. The stochastic analyses show that an error-correcting capacity of the Gray-ECC method is superior to that of the ECC in natural binary codes for changes in signal codewords. Experiments of the Gray-ECC method were conducted on 8-bit monochrome images to evaluate both the features of watermarked images and the performance of robustness for image distortion resulting from the JPEG DCT-baseline coding scheme. The results demonstrate that, compared with a conventional averaging-based method, the Gray-ECC method yields watermarked images with less amount of signal distortion and also makes the watermark comparably robust for lossy data compression. 展开更多
关键词 GRAY CODE error-correcting CODE Digital WATERMARK Spatial Domain JPEG DCT-Based Compression
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Efficient Bit-Plane Based Medical Image Cryptosystem Using Novel and Robust Sine-Cosine Chaotic Map
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作者 Zeric Tabekoueng Njitacke Louai A.Maghrabi +1 位作者 Musheer Ahmad Turki Althaqafi 《Computers, Materials & Continua》 2025年第4期917-933,共17页
This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinea... This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinear analytical tools to thoroughly investigate the dynamics of the chaotic map,which allows us to select optimal parameter configurations for the encryption process.Our findings indicate that the proposed sine-cosine map is capable of generating a rich variety of chaotic attractors,an essential characteristic for effective encryption.The encryption technique is based on bit-plane decomposition,wherein a plain image is divided into distinct bit planes.These planes are organized into two matrices:one containing the most significant bit planes and the other housing the least significant ones.The subsequent phases of chaotic confusion and diffusion utilize these matrices to enhance security.An auxiliary matrix is then generated,comprising the combined bit planes that yield the final encrypted image.Experimental results demonstrate that our proposed technique achieves a commendable level of security for safeguarding sensitive patient information in medical images.As a result,image quality is evaluated using the Structural Similarity Index(SSIM),yielding values close to zero for encrypted images and approaching one for decrypted images.Additionally,the entropy values of the encrypted images are near 8,with a Number of Pixel Change Rate(NPCR)and Unified Average Change Intensity(UACI)exceeding 99.50%and 33%,respectively.Furthermore,quantitative assessments of occlusion attacks,along with comparisons to leading algorithms,validate the integrity and efficacy of our medical image encryption approach. 展开更多
关键词 Image cryptosystem robust chaos sine-cosine map nonlinear analysis tools medical images
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Hardware-Enabled Key Generation in Industry 4.0 Cryptosystems through Analog Hyperchaotic Signals
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作者 Borja Bordel Sánchez Fernando Rodríguez-Sela +1 位作者 Ramón Alcarria Tomás Robles 《Computers, Materials & Continua》 2025年第5期1821-1853,共33页
The Industry 4.0 revolution is characterized by distributed infrastructures where data must be continuously communicated between hardware nodes and cloud servers.Specific lightweight cryptosystems are needed to protec... The Industry 4.0 revolution is characterized by distributed infrastructures where data must be continuously communicated between hardware nodes and cloud servers.Specific lightweight cryptosystems are needed to protect those links,as the hardware node tends to be resource-constrained.Then Pseudo Random Number Generators are employed to produce random keys,whose final behavior depends on the initial seed.To guarantee good mathematical behavior,most key generators need an unpredictable voltage signal as input.However,physical signals evolve slowly and have a significant autocorrelation,so they do not have enough entropy to support highrandomness seeds.Then,electronic mechanisms to generate those high-entropy signals artificially are required.This paper proposes a robust hyperchaotic circuit to obtain such unpredictable electric signals.The circuit is based on a hyperchaotic dynamic system,showing a large catalog of structures,four different secret parameters,and producing four high entropy voltage signals.Synchronization schemes for the correct secret key calculation and distribution among all remote communicating modules are also analyzed and discussed.Security risks and intruder and attacker models for the proposed solution are explored,too.An experimental validation based on circuit simulations and a real hardware implementation is provided.The results show that the random properties of PRNG improved by up to 11%when seeds were calculated through the proposed circuit. 展开更多
关键词 Hyperchaotic circuits chaos synchronization hardware-supported technologies chaotic cryptosystems Industry 4.0 adaptative control
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New Constructions of Dynamic Threshold Cryptosystem 被引量:4
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作者 龙宇 陈克非 毛贤平 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第4期431-435,共5页
This study deals with the dynamic property of threshold cryptosystem. A dynamic threshold cryptosystem allows the sender to choose the authorized decryption group and the threshold value for each message dynamically. ... This study deals with the dynamic property of threshold cryptosystem. A dynamic threshold cryptosystem allows the sender to choose the authorized decryption group and the threshold value for each message dynamically. We first introduce an identity based dynamic threshold cryptosystem, and then use the CanettiHalevi-Katz(CHK) transformation to transform it into a fully secure system in the traditional public key setting.Finally, the elegant dual system encryption technique is applied to constructing a fully secure dynamic threshold cryptosystem with adaptive security. 展开更多
关键词 threshold cryptosystem dynamic property dual system encryption one-time signature
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Enhanced NTRU cryptosystem eliminating decryption failures 被引量:3
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作者 Yao Jun Zeng Guihua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期890-895,共6页
An enhaned NTRU cryptosystem eliminating decryption failures is proposed without using padding schemes and can resist the oracle model andchosen-ciphertext attacks. Because lattice reduction is the main threat to latt... An enhaned NTRU cryptosystem eliminating decryption failures is proposed without using padding schemes and can resist the oracle model andchosen-ciphertext attacks. Because lattice reduction is the main threat to lattice-based cryptosystems, lattice reductionalgorithms are analyzed to evaluate the security of this scheme. Furthermore, the new scheme remains the advantage of high efficiency of original NTRU. 展开更多
关键词 NTRU cryptosystem polynomial algebra decryption failure lattice reduction.
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A novel image block cryptosystem based on a spatiotemporal chaotic system and a chaotic neural network 被引量:1
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作者 王兴元 鲍雪梅 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期232-240,共9页
In this paper, we propose a novel block cryptographic scheme based on a spatiotemporal chaotic system and a chaotic neural network (CNN). The employed CNN comprises a 4-neuron layer called a chaotic neuron layer (... In this paper, we propose a novel block cryptographic scheme based on a spatiotemporal chaotic system and a chaotic neural network (CNN). The employed CNN comprises a 4-neuron layer called a chaotic neuron layer (CNL), where the spatiotemporal chaotic system participates in generating its weight matrix and other parameters. The spatiotemporal chaotic system used in our scheme is the typical coupled map lattice (CML), which can be easily implemented in parallel by hard- ware. A 160-bit-long binary sequence is used to generate the initial conditions of the CML. The decryption process is symmetric relative to the encryption process. Theoretical analysis and experimental results prove that the block cryptosys- tem is secure and practical, and suitable for image encryption. 展开更多
关键词 image encryption block cryptosystem chaotic neural network coupled map lattice
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Efficient Dynamic Threshold Group Signature Scheme Based on Elliptic Curve Cryptosystem 被引量:2
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作者 夏祥胜 洪帆 +1 位作者 耿永军 崔国华 《Journal of Southwest Jiaotong University(English Edition)》 2008年第1期18-23,共6页
The short secret key characteristic of elliptic curve cryptosystem (ECC) are integrated with the ( t, n ) threshold method to create a practical threshold group signature scheme characterized by simultaneous signi... The short secret key characteristic of elliptic curve cryptosystem (ECC) are integrated with the ( t, n ) threshold method to create a practical threshold group signature scheme characterized by simultaneous signing. The scheme not only meets the requirements of anonymity and traceability of group signature but also can withstand Tseng and Wang's conspiracy attack. It allows the group manager to add new members and delete old members according to actual application, while the system parameters have a little change. Cryptanalysis result shows that the scheme is efficient and secure. 展开更多
关键词 Elliptic curve cryptosystem Group signature Threshold scheme Dynamic threshold group signature
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Reversible Video Steganography Using Quick Response Codes and Modified ElGamal Cryptosystem 被引量:2
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作者 Ramadhan J.Mstafa 《Computers, Materials & Continua》 SCIE EI 2022年第8期3349-3368,共20页
The rapid transmission of multimedia information has been achieved mainly by recent advancements in the Internet’s speed and information technology.In spite of this,advancements in technology have resulted in breache... The rapid transmission of multimedia information has been achieved mainly by recent advancements in the Internet’s speed and information technology.In spite of this,advancements in technology have resulted in breaches of privacy and data security.When it comes to protecting private information in today’s Internet era,digital steganography is vital.Many academics are interested in digital video because it has a great capability for concealing important data.There have been a vast number of video steganography solutions developed lately to guard against the theft of confidential data.The visual imperceptibility,robustness,and embedding capacity of these approaches are all challenges that must be addressed.In this paper,a novel solution to reversible video steganography based on Discrete Wavelet Transform(DWT)and Quick Response(QR)codes is proposed to address these concerns.In order to increase the security level of the suggested method,an enhanced ElGamal cryptosystem has also been proposed.Prior to the embedding stage,the suggested method uses the modified ElGamal algorithm to encrypt secret QR codes.Concurrently,it applies two-dimensional DWT on the Y-component of each video frame resulting in Approximation(LL),Horizontal(LH),Vertical(HL),and Diagonal(HH)sub-bands.Then,the encrypted Low(L),Medium(M),Quantile(Q),and High(H)QR codes are embedded into the HL sub-band,HHsub-band,U-component,and V-component of video frames,respectively,using the Least Significant Bit(LSB)technique.As a consequence of extensive testing of the approach,it was shown to be very secure and highly invisible,as well as highly resistant to attacks from Salt&Pepper,Gaussian,Poisson,and Speckle noises,which has an average Structural Similarity Index(SSIM)of more than 0.91.Aside from visual imperceptibility,the suggested method exceeds current methods in terms of Peak Signal-to-Noise Ratio(PSNR)average of 52.143 dB,and embedding capacity 1 bpp. 展开更多
关键词 Reversible video steganography QR code SECURITY ElGamal cryptosystem DWT
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Key Management Using Certificate-Based Cryptosystem in Ad Hoc Networks 被引量:2
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作者 李发根 高军涛 +1 位作者 刘双根 胡予濮 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第2期152-157,共6页
This paper proposed a distributed key management approach by using the recently developed concepts of certificate-based cryptosystem and threshold secret sharing schemes. Without any assumption of prefixed trust relat... This paper proposed a distributed key management approach by using the recently developed concepts of certificate-based cryptosystem and threshold secret sharing schemes. Without any assumption of prefixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide the key generation and key management services using threshold secret sharing schemes, which effectively solves the problem of single point of failure. The proposed approach combines the best aspects of identity-based key management approaches (implicit certification) and traditional public key infrastructure approaches (no key escrow). 展开更多
关键词 ad hoc network network security key management certificate-based cryptosystem
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Image encryption technique based on new two-dimensional fractional-order discrete chaotic map and Menezes–Vanstone elliptic curve cryptosystem 被引量:2
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作者 Zeyu Liu Tiecheng Xia Jinbo Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期161-176,共16页
We propose a new fractional two-dimensional triangle function combination discrete chaotic map(2D-TFCDM)with the discrete fractional difference.Moreover,the chaos behaviors of the proposed map are observed and the bif... We propose a new fractional two-dimensional triangle function combination discrete chaotic map(2D-TFCDM)with the discrete fractional difference.Moreover,the chaos behaviors of the proposed map are observed and the bifurcation diagrams,the largest Lyapunov exponent plot,and the phase portraits are derived,respectively.Finally,with the secret keys generated by Menezes-Vanstone elliptic curve cryptosystem,we apply the discrete fractional map into color image encryption.After that,the image encryption algorithm is analyzed in four aspects and the result indicates that the proposed algorithm is more superior than the other algorithms. 展开更多
关键词 CHAOS fractional two-dimensional triangle function combination discrete chaotic map image encryption Menezes-Vanstone elliptic curve cryptosystem
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An Error-Correcting Code-Based Robust Watermarking Scheme for Stereolithographic Files 被引量:1
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作者 Zhuorong Li Huawei Tian +2 位作者 Yanhui Xiao Yunqi Tang Anhong Wang 《Computer Systems Science & Engineering》 SCIE EI 2021年第5期247-263,共17页
Stereolithographic(STL)files have been extensively used in rapid prototyping industries as well as many other fields as watermarking algorithms to secure intellectual property and protect three-dimensional models from... Stereolithographic(STL)files have been extensively used in rapid prototyping industries as well as many other fields as watermarking algorithms to secure intellectual property and protect three-dimensional models from theft.However,to the best of our knowledge,few studies have looked at how watermarking can resist attacks that involve vertex-reordering.Here,we present a lossless and robust watermarking scheme for STL files to protect against vertexreordering attacks.Specifically,we designed a novel error-correcting code(ECC)that can correct the error of any one-bit in a bitstream by inserting several check digits.In addition,ECC is designed to make use of redundant information according to the characteristics of STL files,which introduces further robustness for defense against attacks.No modifications are made to the geometric information of the three-dimensional model,which respects the requirements of a highprecision model.The experimental results show that the proposed watermarking scheme can survive numerous kinds of attack,including rotation,scaling and translation(RST),facet reordering,and vertex-reordering attacks. 展开更多
关键词 Three-dimensional watermarking stereolithographic file robust watermarking error-correcting code
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Review of Public-Key Cryptosystem Based on the Error Correcting Code 被引量:1
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作者 LI Zhongyuan QU Chengqin +1 位作者 ZHOU Xueguang ZHUO Lifeng 《Wuhan University Journal of Natural Sciences》 CAS 2014年第6期489-496,共8页
The paper review the public-key cryptosystems based on the error correcting codes such as Goppa code, BCH code, RS code, rank distance code, algebraic geometric code as well as LDPC code, and made the comparative anal... The paper review the public-key cryptosystems based on the error correcting codes such as Goppa code, BCH code, RS code, rank distance code, algebraic geometric code as well as LDPC code, and made the comparative analyses of the merits and drawbacks of them. The cryptosystem based on Goppa code has high security, but can be achieved poor. The cryptosystems based on other error correcting codes have higher performance than Goppa code. But there are still some disadvantages to solve. At last, the paper produce an assumption of the Niederreiter cascade combination cryptosystem based on double public-keys under complex circumstances, which has higher performance and security than the traditional cryptosystems. 展开更多
关键词 error correcting code public-key cryptosystem cascaded code safety
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Secure Authentication of WLAN Based on Elliptic Curve Cryptosystem 被引量:1
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作者 张龙军 韩玮 陈克非 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第5期645-650,共6页
The security of wireless local area network (WI.AN) becomes a bottleneck for its further applications. At present, many standard organizations and manufacturers of WLAN try to solve this problem. However, owing to t... The security of wireless local area network (WI.AN) becomes a bottleneck for its further applications. At present, many standard organizations and manufacturers of WLAN try to solve this problem. However, owing to the serious secure leak in IEEES02.11 standards, it is impossible to utterly solve the problem by simply adding some remedies. Based on the analysis on the security mechanism of WLAN and the latest techniques of WI.AN security, a solution to WLAN security was presented. The solution makes preparation for the further combination of WLAN and Internet. 展开更多
关键词 SECURITY wireless local area network (WLAN) elliptic curve cryptosystem
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A JOINT SIGNATURE ENCRYPTION AND ERROR CORRECTION PUBLIC-KEY CRYPTOSYSTEM BASED ON ALGEBRAIC CODING THEORY
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作者 李元兴 成坚 王新梅 《Journal of Electronics(China)》 1992年第1期33-39,共7页
A joint signature,encryption and error correction public-key cryptosystem is pre-sented based on an NP-completeness problem-the decoding problem of general linear codes inalgebraic coding theory,
关键词 CRYPTOLOGY Public-key cryptosystem error-correcting CODES
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Software Watermarking Scheme Based on Multivariate Public Key Cryptosystem
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作者 SUN Xiaoyan ZHANG Maosheng +2 位作者 MAO Shaowu REN Zhengwei ZHANG Huanguo 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2016年第3期257-261,共5页
Software watermarking is an efficient tool to verify the copyright of software. Public key cryptosystem-based watermarking is widely researched. However, the popular public key cryptosystem is not secure under quantum... Software watermarking is an efficient tool to verify the copyright of software. Public key cryptosystem-based watermarking is widely researched. However, the popular public key cryptosystem is not secure under quantum algorithm. This paper proposes a novel soft-ware watermarking scheme based on multivariate public key cryptosystem. The copyright information generated by copyright holder is transformed into copyright numbers using multivariate quadratic polynomial equations inspired by multivariate public key cryptosystem (MPKC). Every polynomial is embedded into the host program independently. Based on the security performance of MPKC, the robustness and invisibility of the proposed scheme is significantly improved in comparison with the RSA-based watermarking method. 展开更多
关键词 SOFTWARE WATERMARKING MULTIVARIATE cryptosystem COPYRIGHT
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Public Key Cryptosystem Based on Two Sided Action of Different Exotic Semirings 被引量:1
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作者 Mariana Durcheva 《Journal of Mathematics and System Science》 2014年第1期6-13,共8页
The idempotent semirings Rmax and Rmin play a crucial role in several areas of mathematics and their applications such as discrete mathematics, algebraic geometry, computer science, computer languages, linguistic prob... The idempotent semirings Rmax and Rmin play a crucial role in several areas of mathematics and their applications such as discrete mathematics, algebraic geometry, computer science, computer languages, linguistic problems, optimization theory, discrete event systems, fuzzy logics. In this paper we consider the expansion of the semirings Rmax and Rmin with residuals and describe how to use these expended semirings in public key cryptography. 展开更多
关键词 Public key cryptosystem exotic semirings semiring action residuals.
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A TTP-Independent Watermarking Protocol Based on Commutative Cryptosystem for Copyright Protection in E-Commerce
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作者 LUO Ting YUAN Jun HONG Fan 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1636-1640,共5页
For the purpose of deterring unauthorized duplication and distribution of multimedia contents in e-commerce, some Buyer-seller watermarking protocols which combine of traditional watermarking and fingerprinting techni... For the purpose of deterring unauthorized duplication and distribution of multimedia contents in e-commerce, some Buyer-seller watermarking protocols which combine of traditional watermarking and fingerprinting techniques have been proposed, However, previous protocols have potential risk from trust third party (TTP) because all entities (including multi-buyers and multi-sellers) mentioned in protocol construct a star tupology like connection, in which the watermark certification authority (WCA) serves as the central point in the interaction and therefore its availability probably turns out to be the vital bottleneck of reliability and efficiency to the whole system. Secondly, WCA holds entire information about watermark used hy Buyers so that an innocent Buyer can he found as guilty if WCA collude with the Seller. In this paper, we propose a watermarking protocol to address the problems using cryptographic technologies in phase of watermark generation. The resuh is a TTP-independent and collusion-secure buyer-seller watermarking protocol. 展开更多
关键词 WATERMARKING copyright protection watermarking protocol commutative cryptosystem
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