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ENHANCING GROUND RESOLUTION OF TM6 BASED ON MULTI-VARIATE REGRESSION MODEL AND SEMI-VARIOGRAM FUNCTION
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作者 MA Hongchao LI Deren 《Geo-Spatial Information Science》 2001年第1期43-49,共7页
It is well known that Landsat TM images are the most widely used remote sensing data in various fields.Usually,it has 7 different electromagnetic spectrum bands,among which the sixth one has much lower ground resoluti... It is well known that Landsat TM images are the most widely used remote sensing data in various fields.Usually,it has 7 different electromagnetic spectrum bands,among which the sixth one has much lower ground resolution compared with the other six bands.Nevertheless,it is useful in the study of rock spectrum reflection,geothermal resources exploration,etc.To improve the ground resolution of TM6 to the level as that of the other six bands is a problem .This paper presents an algorithm based on the combination of multivariate regression model with semivariogram function which can improve the ground resolution of TM6 by "fusing" the data of other six bands.It includes the following main steps: (1) testing the correlation between TM6 and one of TM15,7.If the correlation coefficient between TM6 and another one is greater than a given threshold value,then select the band to the regression analysis as an argument.(2) calculating the size of the template window within which some parameters needed by the regression model will be calculated; (3) replacing the original pixel values of TM6 by those obtained by regression analysis; (4) using image entropy as a measurement to evaluate the quality of the fused image of TM6.The basic mechanism of the algorithm is discussed and the V C ++ program for implementing this algorithm is also presented.A simple application example is given in the last part of this paper,showing the effectiveness of the algorithm. 展开更多
关键词 multi-variate regression model semi-variogram FUNCTION image fusion TEMPLATE WINDOW V C++ PROGRAMMING
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A novel hybrid authentication protocol utilizing lattice-based cryptography for IoT devices in fog networks
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作者 Kumar Sekhar Roy Subhrajyoti Deb Hemanta Kumar Kalita 《Digital Communications and Networks》 SCIE CSCD 2024年第4期989-1000,共12页
The Internet of Things(IoT)has taken the interconnected world by storm.Due to their immense applicability,IoT devices are being scaled at exponential proportions worldwide.But,very little focus has been given to secur... The Internet of Things(IoT)has taken the interconnected world by storm.Due to their immense applicability,IoT devices are being scaled at exponential proportions worldwide.But,very little focus has been given to securing such devices.As these devices are constrained in numerous aspects,it leaves network designers and administrators with no choice but to deploy them with minimal or no security at all.We have seen distributed denial-ofservice attacks being raised using such devices during the infamous Mirai botnet attack in 2016.Therefore we propose a lightweight authentication protocol to provide proper access to such devices.We have considered several aspects while designing our authentication protocol,such as scalability,movement,user registration,device registration,etc.To define the architecture we used a three-layered model consisting of cloud,fog,and edge devices.We have also proposed several pre-existing cipher suites based on post-quantum cryptography for evaluation and usage.We also provide a fail-safe mechanism for a situation where an authenticating server might fail,and the deployed IoT devices can self-organize to keep providing services with no human intervention.We find that our protocol works the fastest when using ring learning with errors.We prove the safety of our authentication protocol using the automated validation of Internet security protocols and applications tool.In conclusion,we propose a safe,hybrid,and fast authentication protocol for authenticating IoT devices in a fog computing environment. 展开更多
关键词 Internet of things AUTHENTICATION Post-quantum cryptography Lattice-based cryptography Cloud computing Fog computing FAIL-SAFE
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Preserving Data Secrecy and Integrity for Cloud Storage Using Smart Contracts and Cryptographic Primitives
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作者 Maher Alharby 《Computers, Materials & Continua》 SCIE EI 2024年第5期2449-2463,共15页
Cloud computing has emerged as a viable alternative to traditional computing infrastructures,offering various benefits.However,the adoption of cloud storage poses significant risks to data secrecy and integrity.This a... Cloud computing has emerged as a viable alternative to traditional computing infrastructures,offering various benefits.However,the adoption of cloud storage poses significant risks to data secrecy and integrity.This article presents an effective mechanism to preserve the secrecy and integrity of data stored on the public cloud by leveraging blockchain technology,smart contracts,and cryptographic primitives.The proposed approach utilizes a Solidity-based smart contract as an auditor for maintaining and verifying the integrity of outsourced data.To preserve data secrecy,symmetric encryption systems are employed to encrypt user data before outsourcing it.An extensive performance analysis is conducted to illustrate the efficiency of the proposed mechanism.Additionally,a rigorous assessment is conducted to ensure that the developed smart contract is free from vulnerabilities and to measure its associated running costs.The security analysis of the proposed system confirms that our approach can securely maintain the confidentiality and integrity of cloud storage,even in the presence of malicious entities.The proposed mechanism contributes to enhancing data security in cloud computing environments and can be used as a foundation for developing more secure cloud storage systems. 展开更多
关键词 Cloud storage data secrecy data integrity smart contracts cryptography
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Trusted Certified Auditor Using Cryptography for Secure Data Outsourcing and Privacy Preservation in Fog-Enabled VANETs
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作者 Nagaraju Pacharla K.Srinivasa Reddy 《Computers, Materials & Continua》 SCIE EI 2024年第5期3089-3110,共22页
With the recent technological developments,massive vehicular ad hoc networks(VANETs)have been established,enabling numerous vehicles and their respective Road Side Unit(RSU)components to communicate with oneanother.Th... With the recent technological developments,massive vehicular ad hoc networks(VANETs)have been established,enabling numerous vehicles and their respective Road Side Unit(RSU)components to communicate with oneanother.The best way to enhance traffic flow for vehicles and traffic management departments is to share thedata they receive.There needs to be more protection for the VANET systems.An effective and safe methodof outsourcing is suggested,which reduces computation costs by achieving data security using a homomorphicmapping based on the conjugate operation of matrices.This research proposes a VANET-based data outsourcingsystem to fix the issues.To keep data outsourcing secure,the suggested model takes cryptography models intoaccount.Fog will keep the generated keys for the purpose of vehicle authentication.For controlling and overseeingthe outsourced data while preserving privacy,the suggested approach considers the Trusted Certified Auditor(TCA).Using the secret key,TCA can identify the genuine identity of VANETs when harmful messages aredetected.The proposed model develops a TCA-based unique static vehicle labeling system using cryptography(TCA-USVLC)for secure data outsourcing and privacy preservation in VANETs.The proposed model calculatesthe trust of vehicles in 16 ms for an average of 180 vehicles and achieves 98.6%accuracy for data encryption toprovide security.The proposedmodel achieved 98.5%accuracy in data outsourcing and 98.6%accuracy in privacypreservation in fog-enabled VANETs.Elliptical curve cryptography models can be applied in the future for betterencryption and decryption rates with lightweight cryptography operations. 展开更多
关键词 Vehicular ad-hoc networks data outsourcing privacy preservation cryptography keys trusted certified auditors data security
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Nested Levels of Hybrid Cryptographical Technique for Secure Information Exchange
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作者 Pawan Kumar Vipin Saxena 《Journal of Computer and Communications》 2024年第2期201-210,共10页
Data security is a very important part of data transmission over insecure channels connected through high-speed networks. Due to COVID-19, the use of data transmission over insecure channels has increased in an expone... Data security is a very important part of data transmission over insecure channels connected through high-speed networks. Due to COVID-19, the use of data transmission over insecure channels has increased in an exponential manner. Hybrid cryptography provides a better solution than a single type of cryptographical technique. In this paper, nested levels of hybrid cryptographical techniques are investigated with the help of Deoxyribonucleic Acid (DNA) and Paillier cryptographical techniques. In the first level, information will be encrypted by DNA and at the second level, the ciphertext of DNA will be encrypted by Paillier cryptography. At the decryption time, firstly Paillier cryptography will be processed, and then DAN cryptography will be processed to get the original text. The proposed algorithm follows the concept of Last Encryption First Decryption (LEFD) at the time of decryption. The computed results are depicted in terms of tables and graphs. 展开更多
关键词 ENCRYPTION DECRYPTION DNA Paillier cryptography Nested Levels Hybrid cryptography
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Utilizing Certificateless Cryptography for IoT Device Identity Authentication Protocols in Web3
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作者 WU Zhihui HONG Yuxuan +2 位作者 ZHOU Enyuan LIU Lei PEI Qingqi 《ZTE Communications》 2024年第2期30-38,共9页
Traditional methods of identity authentication often rely on centralized architectures,which poses risks of computational overload and single points of failure.We propose a protocol that offers a decentralized approac... Traditional methods of identity authentication often rely on centralized architectures,which poses risks of computational overload and single points of failure.We propose a protocol that offers a decentralized approach by distributing authentication services to edge authentication gateways and servers,facilitated by blockchain technology,thus aligning with the decentralized ethos of Web3 infrastructure.Additionally,we enhance device security against physical and cloning attacks by integrating physical unclonable functions with certificateless cryptography,bolstering the integrity of Internet of Thins(IoT)devices within the evolving landscape of the metaverse.To achieve dynamic anonymity and ensure privacy within Web3 environments,we employ fuzzy extractor technology,allowing for updates to pseudonymous identity identifiers while maintaining key consistency.The proposed protocol ensures continuous and secure identity authentication for IoT devices in practical applications,effectively addressing the pressing security concerns inherent in IoT network environments and contributing to the development of robust security infrastructure essential for the proliferation of IoT devices across diverse settings. 展开更多
关键词 blockchain certificateless cryptography identity authentication IOT
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Stability analysis for nonlinear multi-variable delay perturbation problems
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作者 王洪山 张诚坚 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期193-196,共4页
This paper discusses the stability of theoretical solutions for nonlinear multi-variable delay perturbation problems (MVDPP) of the form x′(t)=f(x(t),x(t-τ 1(t)),...,x(t-τ m(t)),y(t),y(t-τ 1(t)),...,y(t-τ m(t... This paper discusses the stability of theoretical solutions for nonlinear multi-variable delay perturbation problems (MVDPP) of the form x′(t)=f(x(t),x(t-τ 1(t)),...,x(t-τ m(t)),y(t),y(t-τ 1(t)),...,y(t-τ m(t))), and εy′(t)=g(x(t),x(t-τ 1(t)),...,x(t-τ m(t)),y(t),y(t-τ 1(t)),...,y(t-τ m(t))), where 0<ε1. A sufficient condition of stability for the systems is obtained. Additionally we prove the numerical solutions of the implicit Euler method are stable under this condition. 展开更多
关键词 multi-variable delay perturbation problems Euler method stability INTERPOLATION
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Public Key Cryptography Based on Ergodic Matrices over Finite Field 被引量:8
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作者 PEI Shihui ZHAO Hongwei ZHAO Yongzhe 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1525-1528,共4页
A new public key encryption scheme is proposed in this paper, which is based on a hard problem over ergodic matrices. The security of this scheme is equal to the MQ-problem: multivariate quadratic equations over fini... A new public key encryption scheme is proposed in this paper, which is based on a hard problem over ergodic matrices. The security of this scheme is equal to the MQ-problem: multivariate quadratic equations over finite fields. This problem has been shown to be NP-complete and can't be solved with polynomial time algorithm. 展开更多
关键词 ergodic matrix strong matrix public key cryptography
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Secure and efficient elliptic curve cryptography resists side-channel attacks 被引量:8
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作者 Zhang Tao Fan Mingyu Zheng Xiaoyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期660-665,共6页
An embedded cryptosystem needs higher reconfiguration capability and security. After analyzing the newly emerging side-channel attacks on elliptic curve cryptosystem (ECC), an efficient fractional width-w NAF (FWNA... An embedded cryptosystem needs higher reconfiguration capability and security. After analyzing the newly emerging side-channel attacks on elliptic curve cryptosystem (ECC), an efficient fractional width-w NAF (FWNAF) algorithm is proposed to secure ECC scalar multiplication from these attacks. This algorithm adopts the fractional window method and probabilistic SPA scheme to reconfigure the pre-computed table, and it allows designers to make a dynamic configuration on pre-computed table. And then, it is enhanced to resist SPA, DPA, RPA and ZPA attacks by using the random masking method. Compared with the WBRIP and EBRIP methods, our proposals has the lowest total computation cost and reduce the shake phenomenon due to sharp fluctuation on computation performance. 展开更多
关键词 elliptic curve cryptography side channel attack simple power attack differential power attack refined power analysis zero-point power analysis.
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Security proof of counterfactual quantum cryptography against general intercept-resend attacks and its vulnerability 被引量:3
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作者 张盛 王剑 唐朝京 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期33-40,共8页
Counterfactual quantum cryptography, recently proposed by Noh, is featured with no transmission of signal parti- cles. This exhibits evident security advantages, such as its immunity to the well-known photon-number-sp... Counterfactual quantum cryptography, recently proposed by Noh, is featured with no transmission of signal parti- cles. This exhibits evident security advantages, such as its immunity to the well-known photon-number-splitting attack. In this paper, the theoretical security of counterfactual quantum cryptography protocol against the general intercept- resend attacks is proved by bounding the information of an eavesdropper Eve more tightly than in Yin's proposal [Phys. Rev. A 82 042335 (2010)]. It is also shown that practical counterfactual quantum cryptography implementations may be vulnerable when equipped with imperfect apparatuses, by proving that a negative key rate can be achieved when Eve launches a time-shift attack based on imperfect detector efficiency. 展开更多
关键词 quantum cryptography quantum counterfactuality quantum information
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RGB Based Multiple Share Creation in Visual Cryptography with Aid of Elliptic Curve Cryptography 被引量:1
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作者 K.Shankar P.Eswaran 《China Communications》 SCIE CSCD 2017年第2期118-130,共13页
In visual cryptography, many shares are generated which are illogical containing certain message within themselves. When all shares are piled jointly, they tend to expose the secret of the image. The notion of visual ... In visual cryptography, many shares are generated which are illogical containing certain message within themselves. When all shares are piled jointly, they tend to expose the secret of the image. The notion of visual secret sharing scheme is to encrypt a secret image into n illogical share images. It is unable to reveal any data on the original image if at least one of the shares is not achieved. The original image, in fact, is realized by overlapping the entire shares directly, in order that the human visual system is competent to identify the collective secret image without employing any complicated computational tools. Therefore, they are communicated steadily as number of shares. The elliptic curve cryptography approach, in turn, is employed to augment the privacy and safety of the image. The new.fangled technique is utilized to generate the multiple shares which are subjected to encryption and decryption by means of the elliptic curve cryptography technique. The test outcomes have revealed the fact that the peak signal to noise ratio is 58.0025, Mean square error value is 0.1164 and the correlation coefficient is 1 for the decrypted image without any sort of distortion of the original image. 展开更多
关键词 visual cryptography PIXEL SHARES elliptic curve cryptography ENCRYPTION PSNR mean square error
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Combined model based on optimized multi-variable grey model and multiple linear regression 被引量:11
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作者 Pingping Xiong Yaoguo Dang +1 位作者 Xianghua wu Xuemei Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期615-620,共6页
The construction method of background value is improved in the original multi-variable grey model (MGM(1,m)) from its source of construction errors. The MGM(1,m) with optimized background value is used to elimin... The construction method of background value is improved in the original multi-variable grey model (MGM(1,m)) from its source of construction errors. The MGM(1,m) with optimized background value is used to eliminate the random fluctuations or errors of the observational data of all variables, and the combined prediction model together with the multiple linear regression is established in order to improve the simulation and prediction accuracy of the combined model. Finally, a combined model of the MGM(1,2) with optimized background value and the binary linear regression is constructed by an example. The results show that the model has good effects for simulation and prediction. 展开更多
关键词 multi-variable grey model (MGM(1 m)) backgroundvalue OPTIMIZATION multiple linear regression combined predic-tion model.
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Memetic Optimization with Cryptographic Encryption for Secure Medical Data Transmission in IoT-Based Distributed Systems 被引量:9
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作者 Srinath Doss Jothi Paranthaman +5 位作者 Suseendran Gopalakrishnan Akila Duraisamy Souvik Pal Balaganesh Duraisamy Chung Le Van Dac-Nhuong Le 《Computers, Materials & Continua》 SCIE EI 2021年第2期1577-1594,共18页
In the healthcare system,the Internet of Things(IoT)based distributed systems play a vital role in transferring the medical-related documents and information among the organizations to reduce the replication in medica... In the healthcare system,the Internet of Things(IoT)based distributed systems play a vital role in transferring the medical-related documents and information among the organizations to reduce the replication in medical tests.This datum is sensitive,and hence security is a must in transforming the sensational contents.In this paper,an Evolutionary Algorithm,namely the Memetic Algorithm is used for encrypting the text messages.The encrypted information is then inserted into the medical images using Discrete Wavelet Transform 1 level and 2 levels.The reverse method of the Memetic Algorithm is implemented when extracting a hidden message from the encoded letter.To show its precision,equivalent to five RGB images and five Grayscale images are used to test the proposed algorithm.The results of the proposed algorithm were analyzed using statistical methods,and the proposed algorithm showed the importance of data transfer in healthcare systems in a stable environment.In the future,to embed the privacy-preserving of medical data,it can be extended with blockchain technology. 展开更多
关键词 Internet of Things medical images cryptography memetic algorithm STEGANOGRAPHY
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Quantum Cryptography for Internet of Things Security 被引量:1
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作者 Alekha Parimal Bhatt Anand Sharma 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第3期213-220,共8页
Internet of things (IoT) is a developing technology with a lot of scope in the future. It can ease various different tasks for us. On one hand, IoT is useful for us, on the other hand, it has many serious security thr... Internet of things (IoT) is a developing technology with a lot of scope in the future. It can ease various different tasks for us. On one hand, IoT is useful for us, on the other hand, it has many serious security threats, like data breaches, side-channel attacks, and virus and data authentication. Classical cryptographic algorithms, like the Rivest-Shamir-Adleman (RSA) algorithm, work well under the classical computers. But the technology is slowly shifting towards quantum computing, which has immense processing power and is more than enough to break the current cryptographic algorithms easily. So it is required that we have to design quantum cryptographic algorithms to prevent our systems from security breaches even before quantum computers come in the market for commercial uses. IoT will also be one of the disciplines, which needs to be secured to prevent any malicious activities. In this paper, we review the common security threats in IoT and the presently available solutions with their drawbacks. Then quantum cryptography is introduced with some of its variations. And finally, the analysis has been carried out in terms of the pros and cons of implementing quantum cryptography for IoT security. 展开更多
关键词 INTERNET of THINGS QUANTUM COMPUTING QUANTUM cryptography SECURITY
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A Visual Cryptography Based Digital Image Copyright Protection 被引量:6
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作者 Adel Hammad Abusitta 《Journal of Information Security》 2012年第2期96-104,共9页
A method for creating digital image copyright protection is proposed in this paper. The proposed method in this paper is based on visual cryptography defined by Noor and Shamir. The proposed method is working on selec... A method for creating digital image copyright protection is proposed in this paper. The proposed method in this paper is based on visual cryptography defined by Noor and Shamir. The proposed method is working on selection of random pixels from the original digital image instead of specific selection of pixels. The new method proposed does not require that the watermark pattern to be embedded in to the original digital image. Instead of that, verification information is generated which will be used to verify the ownership of the image. This leaves the marked image equal to the original image. The method is based on the relationship between randomly selected pixels and their 8-neighbors’ pixels. This relationship keeps the marked image coherent against diverse attacks even if the most significant bits of randomly selected pixels have been changed by attacker as we will see later in this paper. Experimental results show the proposed method can recover the watermark pattern from the marked image even if major changes are made to the original digital image. 展开更多
关键词 IMAGE WATERMARK PATTERN Visual cryptography Digital IMAGE COPYRIGHT
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Construction of General (k, n) Probabilistic Visual Cryptography Scheme 被引量:1
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作者 Ching-Nung Yang Chih-Cheng Wu Feng Liu 《Journal of Electronic Science and Technology》 CAS 2011年第4期317-324,共8页
Visual cryptography scheme (VCS) is a secure method that encrypts a secret image by subdividing it into shadow images. Due to the nature of encryption VCS is categorized into two types: the deterministic VCS (DVCS... Visual cryptography scheme (VCS) is a secure method that encrypts a secret image by subdividing it into shadow images. Due to the nature of encryption VCS is categorized into two types: the deterministic VCS (DVCS) and the probabilistie VCS (PVCS). For the DVCS, we use m (known as the pixel expansion) subpixels to represent a secret pixel. The PVCS uses only one subpixel to represent a secret pixel, while the quality of reconstructed image is degraded. A well-known construction of (k, n)-PVCS is obtained from the (k, n)-DVCS. In this paper, we show another construction of (k, n)-PVCS by extending the (k, k)-PVCS. 展开更多
关键词 Probabilistic visual cryptography visual cryptography visual secret sharing.
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An FPGA Implementation of GF(p) Elliptic Curve Cryptographic Coprocessor 被引量:1
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作者 LIUYu-zhen QINZhong-ping ZHANGHuan-guo 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期31-34,共4页
A GF(p) elliptic curve cryptographic coprocessor is proposed and implemented on Field Programmable Gate Array (FPGA). The focus of the coprocessor is on the most critical, complicated and time-consuming point multipli... A GF(p) elliptic curve cryptographic coprocessor is proposed and implemented on Field Programmable Gate Array (FPGA). The focus of the coprocessor is on the most critical, complicated and time-consuming point multiplications. The technique of coordinates conversion and fast multiplication algorithm of two large integers are utilized to avoid frequent inversions and to accelerate the field multiplications used in point multiplications. The characteristic of hardware parallelism is considered in the implementation of point multiplications. The coprocessor implemented on XILINX XC2V3000 computes a point multiplication for an arbitrary point on a curve defined over GF(2192?264?1) with the frequency of 10 MHz in 4.40 ms in the average case and 5.74 ms in the worst case. At the same circumstance, the coprocessor implemented on XILINX XC2V4000 takes 2.2 ms in the average case and 2.88 ms in the worst case. 展开更多
关键词 elliptic curve cryptosystems cryptographic coprocessor cryptography information security
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A New Fast Modular Arithmetic Method in Public Key Cryptography 被引量:1
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作者 WANG Bangju ZHANG Huanguo 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1645-1648,共4页
Modular arithmetic is a fundamental operation and plays an important role in public key cryptosystem. A new method and its theory evidence on the basis of modular arithmetic with large integer modulus-changeable modul... Modular arithmetic is a fundamental operation and plays an important role in public key cryptosystem. A new method and its theory evidence on the basis of modular arithmetic with large integer modulus-changeable modulus algorithm is proposed to improve the speed of the modular arithmetic in the presented paper. For changeable modulus algorithm, when modular computation of modulo n is difficult, it can be realized by computation of modulo n-1 and n-2 on the perquisite of easy modular computations of modulo n-1 and modulo n-2. The conclusion is that the new method is better than the direct method by computing the modular arithmetic operation with large modulus. Especially, when computations of modulo n-1 and modulo n-2 are easy and computation of modulo n is difficult, this new method will be faster and has more advantages than other algorithms on modular arithmetic. Lastly, it is suggested that the proposed method be applied in public key cryptography based on modular multiplication and modular exponentiation with large integer modulus effectively 展开更多
关键词 public key cryptography modular arithmetic modular multiplication modular exponentiation
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Prediction of rock mass rating using fuzzy logic and multi-variable RMR regression model 被引量:11
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作者 Jalalifar H. Mojedifar S. Sahebi A.A. 《International Journal of Mining Science and Technology》 SCIE EI 2014年第2期237-244,共8页
Rock mass rating system (RMR) is based on the six parameters which was defined by Bieniawski (1989) [1]. Experts frequently relate joint and discontinuities and ground water conditions in linguistic terms with rou... Rock mass rating system (RMR) is based on the six parameters which was defined by Bieniawski (1989) [1]. Experts frequently relate joint and discontinuities and ground water conditions in linguistic terms with rough calculation. As a result, there is a sharp transition between two modules which create doubts. So, in this paper the proposed weights technique was applied for linguistic criteria. Then by using the fuzzy inference system and the multi-variable regression analysis, the accurate RMR is predicted. Before the performing of regression analysis, sensitivity analysis was applied for each of Bieniawski parameters. In this process, the best function was selected among linear, logarithmic, exponential and inverse func- tions and finally it was applied in the regression analysis for construction of a predictive equation. From the constructed regression equation the relative importance of the input parameters can also be observed. It should be noted that joint condition was identified as the most important effective parameter upon RMR. Finally, fuzzy and regression models were validated with the test datasets and it was found that the fuzzy model predicts more accurately RMR than reression models. 展开更多
关键词 Fuzzy set Fuzzy inference system multi-variable regression Rock mass classification
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Quantum Cryptography via Satellite 被引量:2
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作者 Mitch Leslie 《Engineering》 SCIE EI 2019年第3期353-354,共2页
As it circled the Earth one night in 2017, the Chinese satellite Mozi, also called Micius, aimed a laser at a ground station in northeastern China (Fig. 1). Then, as it traveled toward Europe and into range, it direct... As it circled the Earth one night in 2017, the Chinese satellite Mozi, also called Micius, aimed a laser at a ground station in northeastern China (Fig. 1). Then, as it traveled toward Europe and into range, it directed a beam at a different receiver in Austria. These transmissions, delivered to sites 7600 km apart, were noteworthy because they marked the first time a satellite had relayed secret quantum keys for decrypting and viewing messages. With the keys, scientists in China and Austria were able to exchange and decipher encrypted images. And on 29 September 2017, the researchers used the system to set up an encrypted 75-minute video conference between members of the Chinese Academy of Sciences in Beijing and their counterparts at the Austrian Academy of Sciences in Vienna [1]. 展开更多
关键词 QUANTUM cryptography SATELLITE
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