Wei Chen^*, Wuwen Liu, Yue Liang

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 859-872, 2024, DOI:10.32604/fdmp.2023.029310

Abstract River sand is an essential component used as a fine aggregate in mortar and concrete. Due to unrestrained exploitation, river sand resources are gradually being exhausted. This requires alternative solutions. This study deals with the properties of cement mortar containing different levels of manufactured sand (MS) based on quartzite, used to replace river sand. The river sand was replaced at 20%, 40%, 60% and 80% with MS (by weight or volume). The mechanical properties, transfer properties, and microstructure were examined and compared to a control group to study the impact of the replacement level. The results indicate that the compressive… More >

Calvin Hong Li^a, G. P. Peterson^b,*

Frontiers in Heat and Mass Transfer, Vol.1, No.2, pp. 1-10, 2010, DOI:10.5098/hmt.v1.2.3007

Abstract An experimental investigation of the Critical Heat Flux (CHF) and heat transfer coefficient (HTC) of two-phase heat transfer of de-Ionized (DI) water, pool boiling was conducted using several kinds of sintered copper microparticle porous uniform and modulated structures. The modulated porous structure reached a heat flux of 450 W/cm² and a heat transfer coefficient of 230,000 W/m2K. The thick and thin uniform porous structures achieved CHFs of 290 W/cm² and 227 W/cm² , respectively, and heat transfer coefficients of 118,000 W/m²K and 104,000 W/m²K. The mechanisms for the dramatically improved CHFs and HTCs were identified with assistance of a visualization… More >

Khalil Khanafer^a, Kambiz Vafai^b,*

Frontiers in Heat and Mass Transfer, Vol.1, No.2, pp. 1-9, 2010, DOI:10.5098/hmt.v1.2.3004

Abstract A study was conducted to demonstrate the applications of microcantilevers in biomedical and thermo/fluid fields. The deflection of the microcantilevers due to biomaterial and turbulence effects was highlighted in this work. The novel patented microcantilever assemblies that were presented in this study can increase the signal and decrease the unfavorable deflection due to flow disturbances. This work paves the road for researchers in the area microcantilever based biosensors to design efficient microsensor systems that exhibit minimal errors in the measurements. Fluid-structure interaction was also utilized to investigate some aspects of the fluid flow and heat transfer characteristics. More >

Pankaj Saha^a, Gautam Biswas^a,b,*

Frontiers in Heat and Mass Transfer, Vol.2, No.3, pp. 1-5, 2011, DOI:10.5098/hmt.v2.3.3008

Abstract Detailed flow structure in turbulent flows through a rectangular channel containing built-in winglet type vortex generators have been analyzed by means of solutions of the full Navier-Stokes equations using a Large-Eddy Simulation (LES) technique. The Reynolds number of investigation is 6000. The geometry of interest consists of a rectangular channel with a built-in winglet pair on the bottom wall with common-flow-down arrangement. The winglet pair induces streamwise longitudinal vortices behind it. The vortices swirl the flow around the axis parallel to the mainstream direction and disrupt the growth of thermal boundary layer entailing enhancement of heat transfer. The influence of… More >

Nasser Alshammari¹, Shumaila Shahzadi², Saad Awadh Alanazi^1,*, Shahid Naseem³, Muhammad Anwar³, Madallah Alruwaili⁴, Muhammad Rizwan Abid⁵, Omar Alruwaili⁴, Ahmed Alsayat¹, Fahad Ahmad^6,7

Computer Systems Science and Engineering, Vol.48, No.2, pp. 363-394, 2024, DOI:10.32604/csse.2023.040721

Abstract Software Defined Network (SDN) and Network Function Virtualization (NFV) technology promote several benefits to network operators, including reduced maintenance costs, increased network operational performance, simplified network lifecycle, and policies management. Network vulnerabilities try to modify services provided by Network Function Virtualization MANagement and Orchestration (NFV MANO), and malicious attacks in different scenarios disrupt the NFV Orchestrator (NFVO) and Virtualized Infrastructure Manager (VIM) lifecycle management related to network services or individual Virtualized Network Function (VNF). This paper proposes an anomaly detection mechanism that monitors threats in NFV MANO and manages promptly and adaptively to implement and handle security functions in order… More >

Shen Yan¹, Dajiang Geng^2,*, Ning Dai³, Mingjian Long², Zhicheng Bai²

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 2893-2915, 2024, DOI:10.32604/cmes.2024.046931

Abstract According to the design specifications, the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock layer. To address this challenge, a subterranean transfer structure spanning multiple subway tunnels was proposed. Deliberating on the function of piles in the transfer structure as springs with axial and bending stiffness, and taking into account the force balance and deformation coordination conditions of beams and plates within the transfer structure, we established a simplified mechanical model that incorporates soil stratification by combining it with the Winkler elastic foundation beam model. The resolved established simplified mechanical model employed… More >

Weiliang Gao¹, Shixu Jia², Tingting Zhao^2,3,*, Zhiyong Wang²

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 3495-3511, 2024, DOI:10.32604/cmes.2023.046188

Abstract The mechanical properties of interfacial transition zones (ITZs) have traditionally been simplified by reducing the stiffness of cement in previous simulation methods. A novel approach based on the discrete element method (DEM) has been developed for modeling concrete. This new approach efficiently simulates the meso-structure of ITZs, accurately capturing their heterogeneous properties. Validation against established uniaxial compression experiments confirms the precision of this model. The proposed model can model the process of damage evolution containing cracks initiation, propagation and penetration. Under increasing loads, cracks within ITZs progressively accumulate, culminating in macroscopic fractures that traverse the mortar matrix, forming the complex,… More >

Mingzhe Huang, Mi Xiao^*, Liang Gao, Mian Zhou, Wei Sha, Jinhao Zhang

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 2479-2505, 2024, DOI:10.32604/cmes.2023.045735

Abstract Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio. In this paper, a full-scale isogeometric topology optimization (ITO) method based on Kirchhoff–Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is proposed. This method utilizes high-order continuous nonuniform rational B-splines (NURBS) as basis functions for Kirchhoff–Love shell elements. The geometric and analysis models of thin shells are unified by isogeometric analysis (IGA) to avoid geometric approximation error and improve computational accuracy. The topological configurations of thin-shell structures are described by constructing the effective density field on the control… More >

Dandan Wang, Xiaohong Li, Yanwen Zhang^*

Phyton-International Journal of Experimental Botany, Vol.93, No.2, pp. 355-369, 2024, DOI:10.32604/phyton.2024.047183

Abstract Taxus cuspidata is a rare plant with important medicinal and ornamental value. Aiming at the obvious differences between wild and cultivated populations of T. cuspidata from Northeast China, a total of 61 samples, that is, 33 wild yews and 28 cultivated yews were used to analyze the differences and correlations of the kinship, genetic diversity, and genetic structure between them by specific length amplified fragment sequencing (SLAF-seq). Finally, 470725 polymorphic SLAF tags and 58622 valid SNP markers were obtained. Phylogenetic analysis showed that 61 samples were classified into 2 clusters: wild populations and cultivated populations, and some wild yews were… More >

Chengjun Wang^1,2, Fan Ding^2,*, Yiwen Wang¹, Renyuan Wu¹, Xingyu Yao², Chengjie Jiang¹, Liuyi Ling¹

CMC-Computers, Materials & Continua, Vol.78, No.1, pp. 1481-1501, 2024, DOI:10.32604/cmc.2023.046876

Abstract The real-time detection and instance segmentation of strawberries constitute fundamental components in the development of strawberry harvesting robots. Real-time identification of strawberries in an unstructured environment is a challenging task. Current instance segmentation algorithms for strawberries suffer from issues such as poor real-time performance and low accuracy. To this end, the present study proposes an Efficient YOLACT (E-YOLACT) algorithm for strawberry detection and segmentation based on the YOLACT framework. The key enhancements of the E-YOLACT encompass the development of a lightweight attention mechanism, pyramid squeeze shuffle attention (PSSA), for efficient feature extraction. Additionally, an attention-guided context-feature pyramid network (AC-FPN) is… More >