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Chinese Journal of Electronics 2024年第3期33卷 683-693页

作者： Jiamei LIU Lin TAN Hong XU PLA Strategic Support Force Information Engineering University

Deoxys-BC is the primitive tweakable block cipher of the Deoxys family of authenticated encryption schemes.Based on existing related-tweakey boomerang distinguishers,this paper improves the boomerang attacks on 11-round Deoxys-BC-256 and 13-round Deoxys-BC-384 by the optimized key guessing and the precomputation technique.It transfers a part of subtweakey guess in the key-recovery phase to the precomputation resulting in a significant reduction of the overall time complexity.For 11-round Deoxys-BC-256,we give a related-tweakey boomerang attack with time/data/memory complexities of 2218.6/2125.7/2125.7,and give another attack with the less time complexity of2215.8and memory complexity of 2120 when the adversary has access to the full codebook.For 13-round Deoxys-BC-384,we give a related-tweakey boomerang attack with time/dat a/memory complexities of 2k-96+2157.5/2120.4/2113.For the key size k=256,it reduces the time complexity by a factor of 231compared with the previous 13-round boomerang attack.In addition,we present two new related-tweakey boomerang distinguishers on 11-round Deoxys-BC-384 with the same probability as the best previous distinguisher.

关键词： Ciphers Memory management complexity theory Encryption time complexity

ON LOWER BOUNDS OF time complexity OF SOME ALGORITHMS

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Science China Mathematics 1979年第8期 890-900页

作者：洪加威 Beijing Municipal Computing Centre

In this paper, two classes of machines are defined, and the lower bounds of time complexity to compute some problems including sorting and searching on them are examined.

关键词： computer science time complexity lower bounds sorting and searching.

A Theoretical Comparison among Recursive Algorithms for Fast Computation of Zernike Moments Using the Concept of time complexity

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American Journal of Computational Mathematics 2021年第4期11卷 304-326页

作者： Nasrin Bastani Alireza Vard Mehdi Jabalameli Vahid Bastani School of Advanced Technologies in Medicine Isfahan University of Medical Sciences Isfahan Iran Medical Image and Signal Processing Research Center Isfahan University of Medical Sciences Isfahan Iran Computer Department Islamic Azad University Najafabad Branch Isfahan Iran English Department Islamic Azad University Najafabad Branch Isfahan Iran

Zernike polynomials have been used in different fields such as optics, astronomy, and digital image analysis for many years. To form these polynomials, Zernike moments are essential to be determined. One of the main issues in realizing the moments is using factorial terms in their equation which causes higher time complexity. As a solution, several methods have been presented to reduce the time complexity of these polynomials in recent years. The purpose of this research is to study several methods among the most popular recursive methods for fast Zernike computation and compare them together by a global theoretical evaluation system called worst-case time complexity. In this study, we have analyzed the selected algorithms and calculated the worst-case time complexity for each one. After that, the results are represented and explained and finally, a conclusion has been made by comparing these criteria among the studied algorithms. According to time complexity, we have observed that although some algorithms such as Wee method and Modified Prata method were successful in having the smaller time complexities, some other approaches did not make any significant difference compared to the classical algorithm.

关键词： time complexity Uniform Model Zernike Moments Zernike Polynomi-als

Modified Elliptic Curve Cryptography Multi-Signature Scheme to Enhance Security in Cryptocurrency

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Computer Systems Science & Engineering 2023年第4期45卷 641-658页

作者： G.Uganya Radhika Baskar Department of Electronics and Communication Engineering Saveetha School of EngineeringSIMATSChennaiTamil NaduIndia

Internet of Things(IoT)is an emerging technology that moves the world in the direction of smart things.But,IoT security is the complex problem due to its centralized architecture,and limited capacity.So,blockchain technology has great attention due to its features of decentralized architecture,transparency,immutable records and cryptography hash functions when combining with IoT.Cryptography hash algorithms are very important in blockchain technology for secure transmission.It converts the variable size inputs to a fixed size hash output which is unchangeable.Existing cryptography hash algorithms with digital signature have issues of single node accessibility and accessed up to 128 bytes of key size only.As well as,if the attacker tries to hack the key,it cancels the transaction.This paper presents the Modified Elliptic Curve Cryptography Multi Signature Scheme(MECC-MSS)for multiple node accessibility by finding nearest path for secure transaction.In this work,the input key size can be extended up to 512 bytes to enhance the security.The performance of the proposed algorithm is analyzed with other cryptography hash algorithms like Secure Hashing Algorithms(SHAs)such as SHA224,SHA256,SHA384,SHA512,SHA3-224,SHA3-256,SHA3-384,SHA3-512 and Message Digest5 by one-way analysis of variance test in terms of accuracy and time complexity.Results show that the MECC-MSS achieves 90.85%of accuracy and time complexity of 1.4 nano seconds with significance less than 0.05.From the statistical analysis,it is observed that the proposed algorithm is significantly better than other cryptography hash algorithms and also having less time complexity.

关键词： Internet of things blockchain technology secure hash algorithm accuracy time complexity

Smart Bubble Sort:A Novel and Dynamic Variant of Bubble Sort Algorithm

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Computers, Materials & Continua 2022年第6期71卷 4895-4913页

作者： Mohammad Khalid Imam Rahmani College of Computing and Informatics Saudi Electronic UniversityRiyadhSaudi Arabia

In the present era,a very huge volume of data is being stored in online and offline databases.Enterprise houses,research,medical as well as healthcare organizations,and academic institutions store data in databases and their subsequent retrievals are performed for further processing.Finding the required data from a given database within the minimum possible time is one of the key factors in achieving the best possible performance of any computer-based application.If the data is already sorted,finding or searching is comparatively faster.In real-life scenarios,the data collected from different sources may not be in sorted order.Sorting algorithms are required to arrange the data in some order in the least possible time.In this paper,I propose an intelligent approach towards designing a smart variant of the bubble sort algorithm.I call it Smart Bubble sort that exhibits dynamic footprint:The capability of adapting itself from the average-case to the best-case scenario.It is an in-place sorting algorithm and its best-case time complexity isΩ(n).It is linear and better than bubble sort,selection sort,and merge sort.In averagecase and worst-case analyses,the complexity estimates are based on its static footprint analyses.Its complexity in worst-case is O(n2)and in average-case isΘ(n^(2)).Smart Bubble sort is capable of adapting itself to the best-case scenario from the average-case scenario at any subsequent stages due to its dynamic and intelligent nature.The Smart Bubble sort outperforms bubble sort,selection sort,and merge sort in the best-case scenario whereas it outperforms bubble sort in the average-case scenario.

关键词： Sorting algorithms smart bubble sort footprint dynamic footprint time complexity asymptotic analysis

Optimal Algorithms for Integer Inverse Undesirable p-Median Location Problems on Weighted Extended Star Networks

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Journal of the Operations Research Society of China 2021年第1期9卷 99-117页

作者： Esmaeil Afrashteh Behrooz Alizadeh Fahimeh Baroughi Department of Applied Mathematics Faculty of Basic SciencesSahand University of TechnologyTabrizIran

This paper is concerned with the problem of modifying the edge lengths of a weighted extended star network with n vertices by integer amounts at the minimum total cost subject to be given modification bounds so that a set of p prespecified vertices becomes an undesirable p-median location on the perturbed network.We call this problem as the integer inverse undesirable p-median location model.Exact combinatorial algorithms with O(p2n logn)and O(p2(n logn+n log nmax))running times are proposed for solving the problem under the weighted rectilinear and weighted Chebyshev norms,respectively.Furthermore,it is shown that the problem under the weighted sum-type Hamming distance with uniform modification bounds can be solved in O(p-n log n)time.

关键词： Undesirable p-median location Combinatorial optimization Inverse optimization time complexity

Impossible Differential Cryptanalysis of Reduced-Round ARIA and Camellia

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Journal of Computer Science & Technology 2007年第3期22卷 449-456页

作者：吴文玲张文涛冯登国 State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences

This paper studies the security of the block ciphers ARIA and Camellia against impossible differential cryptanalysis. Our work improves the best impossible differential cryptanalysis of ARIA and Camellia known so far. The designers of ARIA expected no impossible differentials exist for 4-round ARIA. However, we found some nontrivial 4-round impossible differentials, which may lead to a possible attack on 6-round ARIA. Moreover, we found some nontrivial 8-round impossible differentials for Camellia, whereas only 7-round impossible differentials were previously known. By using the 8-round impossible differentials, we presented an attack on 12-round Camellia without FL/FL^-1 layers.

关键词： block cipher ARIA Camellia data complexity time complexity impossible differential cryptanalysis

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Quantum algorithms of state estimators in classical control systems

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Science China(Information Sciences) 2020年第9期63卷 243-254页

作者： Kai LI Hongyi DAI Ming ZHANG College of Intelligence Science National University of Defense Technology College of Liberal Arts and Sciences National University of Defense Technology

In this paper, quantum algorithms are applied to the design of state estimators in classical control systems under the condition that quantum algorithms can be physically implemented. We demonstrate that the design of state estimators can be solved by quantum algorithms, which may achieve significant acceleration in comparison to traditional classical algorithms. The time complexity can be reduced from O(n6) to O(qn)when the system matrix is sparse and the condition number κ and the reciprocal of precision ? are small in size O(poly log(n)), where n is the dimension of state x(t) and q is the dimension of input u(t). Our research will provide an entire quantum scheme of constructing state estimators and can be regarded as an attempt to widen application scope of quantum computation.

关键词： quantum computation estimators for linear systems optimization algorithms quantum acceleration time complexity

A Quick Convex Hull Building Algorithm Based on Grid and Binary Tree

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Chinese Journal of Electronics 2015年第2期24卷 317-320页

作者： GAO Yang CHENG Yuhu WANG Xuesong School of Information and Electrical Engineering China University of Mining and Technology

A quick convex hull building algorithm using grid and binary tree is proposed for the minimum convex buidling of planar point set. Grids are used to assess and eliminate those interior points wihtout any contribution to convex hull building and points are sought in the boundary grid only so as to enhance the efficiency of algorithm. The minimum convex bull is built by taking such advantages of binary tree as quick, convenient and applicable for various point sets with different distributions, so as to resolve the description problem of concave point. The time complexity of the algorithm is low because of grid pretreatment. As the results of comparative expriment of random point and actual picture show, the proposed algorithm can obtain the best profile of 2D planar picture with minimum time, which is applicable for describing the shape of irregular convex-concave objects.

关键词： Convex hull Gird Binary tree Concave point time complexity