Mahyar Kargaran^*, Mahmood Farzaneh-Gord

Frontiers in Heat and Mass Transfer, Vol.4, No.1, pp. 1-6, 2013, DOI:10.5098/hmt.v4.1.3007

Abstract Vortex tube is a simple device which separate an inlet gas with a proper pressure into hot and cold flows .This device is well-suited for generating cooling load gas because it provides the cold gas without using any refrigerants . Many research works has been carried out in order to identify the factors which contribute to Vortex tube performance. Here, an experimental study has been made to determine the effect of geometrical (length of vortex tube) and thermo-physical (pressure) parameters on vortex tube performance and air also used as a working fluid. More >

Jinghua Chen^1,#, Zihe Wang^2,#, Fabian Herold³, Alyx Taylor⁴, Jin Kuang¹, Ting Wang¹, Arthur F. Kramer^5,6, Liye Zou^1,*

International Journal of Mental Health Promotion, Vol.25, No.11, pp. 1209-1217, 2023, DOI:10.32604/ijmhp.2023.030539

Abstract A significant portion of emerging adults do not achieve recommended levels of physical activity (PA). Previous studies observed associations between features of emerging adulthood and PA levels, while the potential psychological mechanisms that might explain this phenomenon are not fully understood. In this context, there is some evidence that situated decisions toward physical activity (SDPA) and exercise-intensity tolerance might influence PA level. To provide empirical support for this assumption, the current study investigated whether (i) features of emerging adulthood are linked to SDPA, which, in turn, might affect PA engagement; (ii) exercise-intensity tolerance moderate the relationship between SDPA and PA… More >

Meng Jia, Mingjun Pang^*

Frontiers in Heat and Mass Transfer, Vol.21, pp. 337-366, 2023, DOI:10.32604/fhmt.2023.044286

Abstract The interphase mass, heat transfer efficiency, and flow resistance are strongly dependent on bubble size in gasliquid two-phase systems, so it is very important for engineering applications to effectively control bubble size. In this paper, the formation, growth, and detachment of single bubbles in Newtonian liquids based on capillary needles were studied in detail using a volume of fluid method. The authors investigated the effects of gas injection velocity, gravitational level, surface tension coefficient, needle radius, and liquid−phase properties (liquid viscosity and density) on the process of bubble generation, and the effects of the above factors on bubble shape, detachment… More >

Jiangxia Han^1,2, Liang Xue^1,2,*, Ying Jia³, Mpoki Sam Mwasamwasa^1,2, Felix Nanguka⁴, Charles Sangweni⁵, Hailong Liu³, Qian Li³

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.2, pp. 1323-1340, 2024, DOI:10.32604/cmes.2023.031093

Abstract Recent advances in deep neural networks have shed new light on physics, engineering, and scientific computing. Reconciling the data-centered viewpoint with physical simulation is one of the research hotspots. The physics-informed neural network (PINN) is currently the most general framework, which is more popular due to the convenience of constructing NNs and excellent generalization ability. The automatic differentiation (AD)-based PINN model is suitable for the homogeneous scientific problem; however, it is unclear how AD can enforce flux continuity across boundaries between cells of different properties where spatial heterogeneity is represented by grid cells with different physical properties. In this work,… More >

Farhan Amin, Gyu Sang Choi^*

CMC-Computers, Materials & Continua, Vol.77, No.1, pp. 1165-1181, 2023, DOI:10.32604/cmc.2023.040693

Abstract In recent years, the Internet of Things (IoT) has played a vital role in providing various services to users in a smart city. However, searching for services, objects, data, and frameworks remains a concern. The technological advancements in Cyber-Physical Systems (CPSs) and the Social Internet of Things (SIoT) open a new era of research. Thus, we propose a Cyber-Physical-Social Systems (CPSs) for service search. Herein, service search and object discovery operation carries with the suitable selection of friends in the network. Our proposed model constructs a graph and performs social network analysis (SNA). We suggest degree centrality, clustering, and scale-free… More >

Jianguo Wang¹, Kuan Zhang^1,*, Yuesheng Zhao^2,*, Xiaoling Wang², Muhammad Shamrooz Aslam²

CMC-Computers, Materials & Continua, Vol.77, No.1, pp. 79-96, 2023, DOI:10.32604/cmc.2023.040506

Abstract The purpose of Human Activities Recognition (HAR) is to recognize human activities with sensors like accelerometers and gyroscopes. The normal research strategy is to obtain better HAR results by finding more efficient eigenvalues and classification algorithms. In this paper, we experimentally validate the HAR process and its various algorithms independently. On the base of which, it is further proposed that, in addition to the necessary eigenvalues and intelligent algorithms, correct prior knowledge is even more critical. The prior knowledge mentioned here mainly refers to the physical understanding of the analyzed object, the sampling process, the sampling data, the HAR algorithm,… More >

Jialing Miao¹, Wei Liao^2,*, Baoguo Xie³

International Journal of Mental Health Promotion, Vol.25, No.10, pp. 1147-1157, 2023, DOI:10.32604/ijmhp.2023.030671

Abstract Although employers believe that encouraging and supporting physical exercise activities by purchasing fitness equipment and building sports venues can improve employees’ well-being, the utilization rate is rather low. Since most of the evidence of the well-being promotion in the workplace concentrated on the perspectives of organizational factors and psychosocial factors and focused on the reduction of the negative affect of well-being, it is still an open question whether physical exercise has benefits on both negative and positive affect of wellbeing and who benefits more from physical exercise. Thus, the purpose of this study is to investigate the impact of physical… More >

Liuhuo Wang¹, Qingcui Liu², Wenwei Zhu³, Yanru Wang⁴, Yi Tian^4,*, Long Zhao⁴

Energy Engineering, Vol.120, No.11, pp. 2651-2666, 2023, DOI:10.32604/ee.2023.027791

Abstract The electromagnetic losses of submarine cables are mainly caused by the metal shielding layer to prevent the water tree effect and the armor layer that strengthens the strength of the submarine cables. While these losses cause the temperature of submarine cable to rise, and temperature variation will in turn change the conductivity of its metal layer material. In this paper, the electric-magnetic-thermal multi-physical field coupling of the electromagnetic loss variation of the submarine cable is realized by establishing a full coupling system containing Fourier’s law and Maxwell-Ampère’s Law for the photoelectric composite submarine cable. The multi-physical field coupling model is… More > Graphic Abstract

Borja Bordel Sánchez^1,*, Ramón Alcarria², Tomás Robles¹

CMC-Computers, Materials & Continua, Vol.76, No.3, pp. 3189-3218, 2023, DOI:10.32604/cmc.2023.039466

Abstract Cyber-Physical Systems are very vulnerable to sparse sensor attacks. But current protection mechanisms employ linear and deterministic models which cannot detect attacks precisely. Therefore, in this paper, we propose a new non-linear generalized model to describe Cyber-Physical Systems. This model includes unknown multivariable discrete and continuous-time functions and different multiplicative noises to represent the evolution of physical processes and random effects in the physical and computational worlds. Besides, the digitalization stage in hardware devices is represented too. Attackers and most critical sparse sensor attacks are described through a stochastic process. The reconstruction and protection mechanisms are based on a weighted… More >

Baofeng Ji^1,2,3,4,*, Yifan Liu^1,2,3,4, Tingpeng Li¹, Ling Xing², Weixing Wang², Shahid Mumtaz⁵, Xiaolong Shang⁶, Wanying Liu², Congzheng Han⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 679-689, 2024, DOI:10.32604/cmes.2023.028667

Abstract With the development of information technology, more and more devices are connected to the Internet through wireless communication to complete data interconnection. Due to the broadcast characteristics of wireless channels, wireless networks have suffered more and more malicious attacks. Physical layer security has received extensive attention from industry and academia. MIMO is considered to be one of the most important technologies related to physical layer security. Through beamforming technology, messages can be transmitted to legitimate users in an offset direction that is as orthogonal as possible to the interference channel to ensure the reception SINR by legitimate users. Combining the… More >