Zilong Hu¹, Weilong Guang¹, Ran Tao^1,2,*, Ruofu Xiao^1,2, Di Zhu³

Frontiers in Heat and Mass Transfer, Vol.21, pp. 161-178, 2023, DOI:10.32604/fhmt.2023.041402

Abstract Cavitation and cavitation erosion often occur and seriously threaten the safe and stable operation of hydraulic machinery. However, during the operation of hydraulic machinery, the cavitation flow field is often difficult to contact and measure, and the shedding and development characteristics of cavitation flow are unknown. This paper uses the Detached Eddy Simulation (DES) turbulence model and Zwart-Gerber-Belamri (ZGB) cavitation model to conduct numerical research on the cavitation flow of a twisted hydrofoil and verifies the effectiveness of numerical simulation by comparing it with experimental results. Then, based on the fractal dimension method, the number and fractal dimension of the… More >

Wei Xiong^1,2, Dagang Li^1,*, Peixing Wei², Lin Wang², Qian Feng¹

Journal of Renewable Materials, Vol.11, No.5, pp. 2265-2278, 2023, DOI:10.32604/jrm.2023.025483

Abstract Poplar wood, which was used as the absorption material for the solar-driven interfacial evaporation, was treated for 3 days, 6 days and 9 days with the pectinase, and then was simulated for photothermal evaporation test at one standard solar radiation intensity (1 kW⋅m⁻²). The effects of pectinase treatment on cell passage and water migration capacity of poplars were analyzed by the mercury intrusion porosimetry, the scanning electron microscope and fractal theory. It was found that the pit membrane and the ray parenchyma cells of poplar wood were degraded and destroyed after pectinase treatment. Compared with the untreated poplar wood, the evaporation… More >

Yiguang Wang^1,2, Zhe Zhang¹, Xun Zhang^1,*

Journal of Renewable Materials, Vol.11, No.3, pp. 1321-1337, 2023, DOI:10.32604/jrm.2022.023266

Abstract Fibre can enhance the mechanical properties of cement-based composites, but fibre also degrades their workability. However, the quantitative effects of fiber content and length-diameter ratio on alkali-activated materials are still unclear. Various aspect ratio, volume fraction of polyvinyl alcohol fibre (PVAF), and various water-binder ratio were employed to prepare a total of 26 groups of fibre reinforced alkali-activated composite (FRAAC). The influence of PVAF fibre factor (product of fiber volume fraction and length-diameter ratio) on flowability, compactness, strength, and crack fractal dimension of FRAAC was researched. The influence of water-binder ratio on the plastic viscosity of FRAAC was more significant… More >

Farid Nahli1¹, Alexander Paramonov¹, Naglaa F. Soliman², Hussah Nasser AlEisa^3,*, Reem Alkanhel², Ammar Muthanna¹, Abdelhamied A. Ateya⁴

Intelligent Automation & Soft Computing, Vol.36, No.1, pp. 561-572, 2023, DOI:10.32604/iasc.2023.031299

Abstract Next-generation networks, including the Internet of Things (IoT), fifth-generation cellular systems (5G), and sixth-generation cellular systems (6G), suffer from the dramatic increase of the number of deployed devices. This puts high constraints and challenges on the design of such networks. Structural changing of the network is one of such challenges that affect the network performance, including the required quality of service (QoS). The fractal dimension (FD) is considered one of the main indicators used to represent the structure of the communication network. To this end, this work analyzes the FD of the network and its use for telecommunication networks investigation… More >

Shuaibing Li^1,*, Jiaqi Cui², Yongqiang Kang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.2, pp. 1083-1099, 2022, DOI:10.32604/cmes.2022.019671

Abstract The insulating paper of the transformer is affected by many factors during the operation, meanwhile, the surface texture of the paper is easy to change. To explore the relationship between the aging state and surface texture change of insulating paper, firstly, the thermal aging experiment of insulating paper is carried out, and the insulating paper samples with different aging times are obtained. After then, the images of the aged insulating paper samples are collected and pre-processed. The pre-processing effect is verified by constructing and calculating the gray surface of the sample. Secondly, the texture features of the insulating paper image… More >

Sk Sarif Hassan¹, Ranjeet Kumar Rout², Kshira Sagar Sahoo³, Nz Jhanjhi⁴, Saiyed Umer⁵, Thamer A. Tabbakh^6,*, Zahrah A. Almusaylim⁷

CMC-Computers, Materials & Continua, Vol.69, No.3, pp. 3477-3493, 2021, DOI:10.32604/cmc.2021.017206

Abstract Coronaviruses are responsible for various diseases ranging from the common cold to severe infections like the Middle East syndromes and the severe acute respiratory syndrome. However, a new coronavirus strain known as COVID-19 developed into a pandemic resulting in an ongoing global public health crisis. Therefore, there is a need to understand the genomic transformations that occur within this family of viruses in order to limit disease spread and develop new therapeutic targets. The nucleotide sequences of SARS-CoV-2 are consist of several bases. These bases can be classified into purines and pyrimidines according to their chemical composition. Purines include adenine… More >

Yong Wang, Yongyan Wang^*, Nan Qin, Sa Huang, Le Chang, Shunzheng Hou

Computer Systems Science and Engineering, Vol.39, No.1, pp. 121-131, 2021, DOI:10.32604/csse.2021.014464

Abstract The work presented in this paper was conducted to quantify the relationship between the pore characteristics and mechanical properties of white sandstone. The study include tests carried out under the coupling effects of chemical corrosion, temperature, nuclear magnetic resonance, and mechanical tests. Computer fractal theory was employed to describe and quantify the characteristics of the growth of pores in white sandstone under the same coupling effect. A custom developed program code, in the MATLAB software platform, was used for calculating the growths of the pores in white sandstone when subjected to coupling effects. The correlation between the computer fractal dimension… More >

Lei Guo^1,2,3,4, Pingping Chen¹, Lixia Guo^1,2,3,*, Zhilong Xue⁴, Zi Guan¹, Mingru Li¹

Journal of Renewable Materials, Vol.9, No.10, pp. 1805-1819, 2021, DOI:10.32604/jrm.2021.015140

Abstract In order to explore the relationship between the macroscopic properties and pore structure characteristics of baking-free slag-sludge bricks, the compressive strength and water absorption rate using aluminum industrial slag and sludge of different substitution rates were tested. Optical instruments and image analysis software were used to measure the parameters of the pore structure. Specifically, a fractal model was built based on the fractal theory, in which the fractal dimension was used as the characteristic index of the pore structure to analyze the correlation and interaction mechanism between the fractal dimension and the macroscopic mechanical properties. Based on this study, conclusions… More >

K. Umesh¹, R. Ganguli¹

CMC-Computers, Materials & Continua, Vol.41, No.3, pp. 215-240, 2014, DOI:10.3970/cmc.2014.041.215

Abstract Fractal dimension based damage detection method is investigated for a composite plate with random material properties. Composite material shows spatially varying random material properties because of complex manufacturing processes. Matrix cracks are considered as damage in the composite plate. Such cracks are often seen as the initial damage mechanism in composites under fatigue loading and also occur due to low velocity impact. Static deflection of the cantilevered composite plate with uniform loading is calculated using the finite element method. Damage detection is carried out based on sliding window fractal dimension operator using the static deflection. Two dimensional homogeneous Gaussian random… More >