Meng-Wei Zhang¹, Xiu-Bo Chen¹, Haseeb Ahmad², Gang Xu^3,4,*, Yi-Xian Yang¹

Journal of Cyber Security, Vol.4, No.1, pp. 29-39, 2022, DOI:10.32604/jcs.2022.027693

Abstract Blockchain has a profound impact on all areas of society by virtue of its immutability, decentralization and other characteristics. However, blockchain faces the problem of data privacy leakage during the application process, and the rapid development of quantum computing also brings the threat of quantum attack to blockchain. In this paper, we propose a lattice-based certificateless fully homomorphic encryption (LCFHE) algorithm based on approximate eigenvector firstly. And we use the lattice-based delegate algorithm and preimage sampling algorithm to extract part of the private key based on certificateless scheme, which is composed of the private key together with the secret value… More >

Gang Xu¹, Yibo Cao¹, Shiyuan Xu¹, Xin Liu^2,*, Xiu-Bo Chen³, Yiying Yu¹, Xiaojun Wang⁴

CMC-Computers, Materials & Continua, Vol.72, No.3, pp. 5429-5441, 2022, DOI:10.32604/cmc.2022.028562

Abstract With the increasing popularity of cloud storage, data security on the cloud has become increasingly visible. Searchable encryption has the ability to realize the privacy protection and security of data in the cloud. However, with the continuous development of quantum computing, the standard Public-key Encryption with Keyword Search (PEKS) scheme cannot resist quantum-based keyword guessing attacks. Further, the credibility of the server also poses a significant threat to the security of the retrieval process. This paper proposes a searchable encryption scheme based on lattice cryptography using blockchain to address the above problems. Firstly, we design a lattice-based encryption primitive to… More >

Yongli Tang¹, Yuanhong Li¹, Qing Ye^1,*, Ying Li¹, Xiaojun Wang²

CMC-Computers, Materials & Continua, Vol.72, No.2, pp. 4069-4085, 2022, DOI:10.32604/cmc.2022.026820

Abstract Although the existing group signature schemes from lattice have been optimized for efficiency, the signing abilities of each member in the group are relatively single. It may not be suitable for complex applications. Inspired by the pioneering work of Bellare and Fuchsbauer, we present a primitive called policy-based group signature. In policy-based group signatures, group members can on behalf of the group to sign documents that meet their own policies, and the generated signatures will not leak the identity and policies of the signer. Moreover, the group administrator is allowed to reveal the identity of signer when a controversy occurs.… More >

Jun Yan^1,2, Qianqian Sui¹, Zhirui Fan¹, Zunyi Duan^3,*

CMES-Computer Modeling in Engineering & Sciences, Vol.130, No.2, pp. 967-986, 2022, DOI:10.32604/cmes.2022.017708

Abstract This study establishes a multiscale and multi-material topology optimization model for thermoelastic lattice structures (TLSs) considering mechanical and thermal loading based on the Extended Multiscale Finite Element Method (EMsFEM). The corresponding multi-material and multiscale mathematical formulation have been established with minimizing strain energy and structural mass as the objective function and constraint, respectively. The Solid Isotropic Material with Penalization (SIMP) interpolation scheme has been adopted to realize micro-scale multi-material selection of truss microstructure. The modified volume preserving Heaviside function (VPHF) is utilized to obtain a clear 0/1 material of truss microstructure. Compared with the classic topology optimization of single-material TLSs,… More >

Gang Xu^1,2, Yibo Cao¹, Shiyuan Xu¹, Ke Xiao¹, Xin Liu³, Xiubo Chen^4,*, Mianxiong Dong⁵

Computer Systems Science and Engineering, Vol.41, No.3, pp. 945-958, 2022, DOI:10.32604/csse.2022.022100

Abstract In recent decades, log system management has been widely studied for data security management. System abnormalities or illegal operations can be found in time by analyzing the log and provide evidence for intrusions. In order to ensure the integrity of the log in the current system, many researchers have designed it based on blockchain. However, the emerging blockchain is facing significant security challenges with the increment of quantum computers. An attacker equipped with a quantum computer can extract the user's private key from the public key to generate a forged signature, destroy the structure of the blockchain, and threaten the… More >

Peng Gao^*, Marek Perkowski, Yiwei Li, Xiaoyu Song

CMC-Computers, Materials & Continua, Vol.70, No.3, pp. 4545-4561, 2022, DOI:10.32604/cmc.2022.020483

Abstract After Google reported its realization of quantum supremacy, Solving the classical problems with quantum computing is becoming a valuable research topic. Switching function minimization is an important problem in Electronic Design Automation (EDA) and logic synthesis, most of the solutions are based on heuristic algorithms with a classical computer, it is a good practice to solve this problem with a quantum processer. In this paper, we introduce a new hybrid classic quantum algorithm using Grover’s algorithm and symmetric functions to minimize small Disjoint Sum of Product (DSOP) and Sum of Product (SOP) for Boolean switching functions. Our method is based… More >

Lin Mei¹, Chungen Xu^1,*, Lei Xu¹, Xiaoling Yu², Cong Zuo³

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 2299-2314, 2021, DOI:10.32604/cmc.2021.017216

Abstract Internet of Things (IoT), which provides the solution of connecting things and devices, has increasingly developed as vital tools to realize intelligent life. Generally, source-limited IoT sensors outsource their data to the cloud, which arises the concerns that the transmission of IoT data is happening without appropriate consideration of the profound security challenges involved. Though encryption technology can guarantee the confidentiality of private data, it hinders the usability of data. Searchable encryption (SE) has been proposed to achieve secure data sharing and searching. However, most of existing SE schemes are designed under conventional hardness assumptions and may be vulnerable to… More >

Xiaokang Tian¹, Kai Yue^1,2,*, Yu You^1,2, Yongjian Niu¹, Xinxin Zhang^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 301-317, 2021, DOI:10.32604/fdmp.2021.013521

Abstract The heat transfer performances of a microchannel heat sink in the presence of a nanofluid can be affected by the attachment of nanoparticle (NP) on the microchannel wall. In this study, the mechanisms underlying NP transport and attachment are comprehensively analyzed by means of a coupled double-distribution-function lattice Boltzmann model combined with lattice-gas automata. Using this approach, the temperature distribution and the two-phase flow pattern are obtained for different values of the influential parameters. The results indicate that the number of attached NPs decrease exponentially as their diameter and the fluid velocity grow. An increase in the wall temperature leads… More >

Yun Zhao, Shi Yan^*, Jiale Jia

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.3, pp. 1251-1274, 2021, DOI:10.32604/cmes.2021.013478

Abstract In this study, the pyramidal lattice stitched foam sandwich composite materials were manufactured by integrating top and bottom panels with pyramidal lattice core to overcome the weak interface between the core and the skins of the sandwich structure. The influence of the reinforcing core rods on the mechanical properties including compressive, shear, and three-point bending performances of the foam sandwich composite materials were revealed through theoretical analysis and comparative experiments. The theoretical predictions were consistent with the experimental results. Compressive test, shear test and three-point bending test were performed. The experimental results show that the core rods can significantly improve… More >

T. Ahmed¹, S. Hassan^1,2, M. F. Hasan³, M. M. Molla^1,2,*, M. A. Taher⁴, S. C. Saha⁵

Energy Engineering, Vol.118, No.1, pp. 15-36, 2021, DOI:10.32604/EE.2020.011237

Abstract The magneto-hydrodynamics (MHD) effect is studied at different inclined angles in Rayleigh-Bénard (RB) convection inside a rectangular enclosure using the lattice Boltzmann method (LBM). The enclosure is filled with electrically conducting fluids of different characteristics. These characteristics are defined by Prandtl number, Pr. The considered Pr values for this study are 10 and 70. The influence of other dimensionless parameters Rayleigh numbers Ra = 10³; 10⁴; 10⁵; 10⁶ and Hartmann numbers Ha = 0, 10, 25, 50, 100, on fluid flow and heat transfer, are also investigated considering different inclined angles φ of magnetic field by analyzing computed local Nusselt… More >