Yingying Li¹, Hang Jiang¹, Lianjie Yu¹, Jianfeng Li^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.3, pp. 2123-2136, 2023, DOI:10.32604/cmes.2022.021407

Abstract To improve the estimation accuracy, a novel time delay estimation (TDE) method based on the closed-form offset compensation is proposed. Firstly, we use the generalized cross-correlation with phase transform (GCC-PHAT) method to obtain the initial TDE. Secondly, a signal model using normalized cross spectrum is established, and the noise subspace is extracted by eigenvalue decomposition (EVD) of covariance matrix. Using the orthogonal relation between the steering vector and the noise subspace, the first-order Taylor expansion is carried out on the steering vector reconstructed by the initial TDE. Finally, the offsets are compensated via simple least squares (LS). Compared to other… More >

Lixing Zheng^1,*, Weibo Wang², Yiyan Zhang¹, Lingmei Wang³, Wei Lu²

CMES-Computer Modeling in Engineering & Sciences, Vol.133, No.1, pp. 153-170, 2022, DOI:10.32604/cmes.2022.021235

Abstract An improved model to calculate the length of the mixing chamber of the ejector was proposed on the basis of the Fano flow model, and a method to optimize the structures of the mixing chamber and diffuser of the ejector was put forward. The accuracy of the model was verified by comparing the theoretical results calculated using the model to experimental data reported in literature. Variations in the length of the mixing chamber L_m and length of the diffuser L_d with respect to variations in the outlet temperature of the ejector T_c, outlet pressure of the ejector p_c, and the… More >

Abdul Aabid^1,*, Sher Afghan Khan², Muneer Baig¹

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.6, pp. 1877-1900, 2022, DOI:10.32604/fdmp.2022.021860

Abstract A method based on microjets is implemented to control the flow properties in a convergent-divergent nozzle undergoing a sudden expansion. Three different variants of this active control technique are explored numerically by means of a finite-volume method for compressible fluid flow: with the first one, the control is implemented at the base, with the second at the wall, while the third one may be regarded as a combination of these. When jets are over-expanded, the control is not very effective. However, when a favourable pressure gradient is established in the nozzle, the control becomes effective, leading to an increase in… More >

Wenzheng Yu¹, Mingxuan Zhu¹, Li Shao¹, Yanbo Shen^2,3,*, Haitao Liu¹, Tianliang Chen¹, Hanxiaoya Zhang⁴

CMC-Computers, Materials & Continua, Vol.73, No.2, pp. 3771-3793, 2022, DOI:10.32604/cmc.2022.027094

Abstract Qinghai Lake Basin area in Gangcha county is selected as the study area in terms of desertification change features in this paper. Based on the remote sensing (RS) and global positioning system (GPS) technologies, the desertification information range from 1989 to 2014 in the study area is extracted. Using the method of the decision tree, the desertification in the research area is been divided into four grades including mild desertification, moderate desertification, severe desertification and serious desertification. The change characteristics of desertification in the study area were analyzed in detail, which showed that the desertification in the study area experienced… More >

Shenglong Wang^1,*, Jing Yang^1,*, Xiaoyu Ding², Jianpei Zhang¹, Meng Zhao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.132, No.1, pp. 215-249, 2022, DOI:10.32604/cmes.2022.018050

Abstract In recent years, local community detection algorithms have developed rapidly because of their nearly linear computing time and the convenience of obtaining the local information of real-world networks. However, there are still some issues that need to be further studied. First, there is no local community detection algorithm dedicated to detecting a seed-oriented local community, that is, the local community with the seed as the core. The second and third issues are that the quality of local communities detected by the previous local community detection algorithms are largely dependent on the position of the seed and predefined parameters, respectively. To… More >

Hongfei Yue¹, Aiguo Fang², Sudong Hua^1,*, Zenghuan Gu³, Yu Jia¹, Cheng Yang⁴

Journal of Renewable Materials, Vol.10, No.8, pp. 2247-2261, 2022, DOI:10.32604/jrm.2022.018901

Abstract A phosphogypsum-based subgrade stabilizer (PBSS) was formulated using industrial by-product phosphogypsum (PG), mixed with slag and calcium-silicon-rich active material (GSR). The active powder (AP) was used to modify PBSS, and PBSS-AP was obtained. PBSS and PBSS-AP were each mixed with 10% silty soil, and cement and lime (CAL: 5% lime + 2% cement) were used as the traditional material for comparative experiments. Samples were cured under standard conditions, and tested for unconfined compressive strength (UCS), water stability, volume expansion, and leachate, to explore the stabilization effect of the three solidified materials on silty soil. The results showed that the comprehensive… More >

Abhishek Kumar Shukla^*, Sujoy Das

CMC-Computers, Materials & Continua, Vol.71, No.2, pp. 3557-3570, 2022, DOI:10.32604/cmc.2022.022411

Abstract The neural network has attracted researchers immensely in the last couple of years due to its wide applications in various areas such as Data mining, Natural language processing, Image processing, and Information retrieval etc. Word embedding has been applied by many researchers for Information retrieval tasks. In this paper word embedding-based skip-gram model has been developed for the query expansion task. Vocabulary terms are obtained from the top “k” initially retrieved documents using the Pseudo relevance feedback model and then they are trained using the skip-gram model to find the expansion terms for the user query. The performance of the… More >

Yujie Huang¹, Yifan Zhang¹, Zheng Wang^1,*, Assima Dauletbe², Yao Lu¹, Zhaoyu Shen¹

Journal of Renewable Materials, Vol.10, No.3, pp. 849-870, 2022, DOI:10.32604/jrm.2022.018515

Abstract To describe the dynamic cracking process of the CLT vertical layer, the correlation between a load-displacement curve, specimen cracking, and planar shear failure mechanism of the CLT were explored. A three-point bending test and an improved planar shear test are used to evaluate the shear performance of the CLT. In this study, the load-displacement curve is recorded, the experimental part is synchronized with the video, the dynamic process of cracking of the vertical layer is observed and analyzed throughout the test. From the load-displacement curve, the image characteristics of the initial cracking and the sudden increase of the cracking of… More > Graphic Abstract

T. Manoj Kumar^1,*, P. Karthigaikumar²

Intelligent Automation & Soft Computing, Vol.31, No.2, pp. 1025-1036, 2022, DOI:10.32604/iasc.2022.020090

Abstract

Data security is an essential aspect of data communication and data storage. To provide high-level security against all kinds of unauthorized accesses, cryptographic algorithms have been applied to various fields such as medical and military applications. Advanced Encryption Standard (AES), a symmetric cryptographic algorithm, is acknowledged as the most secure algorithm for the cryptographic process globally. Several modifications have been made to the original architecture after it was proposed by two Belgian researchers, Joan Daemen and Vincent Rijment, at the third AES candidate Conference in 2000. The existing modifications aim to increase security and speed. This paper proposes an efficient… More >

Yan Hong¹, Bai-Ni Guo^2,*, Feng Qi³

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.1, pp. 409-423, 2021, DOI:10.32604/cmes.2021.016431

Abstract In the paper, by virtue of a general formula for any derivative of the ratio of two differentiable functions, with the aid of a recursive property of the Hessenberg determinants, the authors establish determinantal expressions and recursive relations for the Bessel zeta function and for a sequence originating from a series expansion of the power of modified Bessel function of the first kind. More >