Mingxing Zhu, Yansong Wang, Ruyun Zhang, Tianning Zhang, Heyuan Li, Hanguang Luo, Shunbin Li^*

Journal on Internet of Things, Vol.3, No.3, pp. 99-107, 2021, DOI:10.32604/jiot.2021.014921

Abstract The Mimic Defense (MD) is an endogenous security technology with the core technique of Dynamic Heterogeneous Redundancy (DHR) architecture. It can effectively resist unknown vulnerabilities, backdoors, and other security threats by schedule strategy, negative feedback control, and other mechanisms. To solve the problem that Cyber Mimic Defense devices difficulty of supporting the TCP protocol. This paper proposes a TCP protocol normalization scheme for DHR architecture. Theoretical analysis and experimental results show that this scheme can realize the support of DHR-based network devices to TCP protocol without affecting the security of mimicry defense architecture. More >

Jesus Hamilton Ortiz¹, Osamah Ibrahim Khalaf², Fernando Velez Varela^3,*, Nicolas Minotta Rodriguez³, Christian Andres Mosquera Gil³

Journal on Internet of Things, Vol.3, No.3, pp. 87-97, 2021, DOI:10.32604/jiot.2021.014737

Abstract In recent years, the Internet has gradually developed into a mature tool, which can integrate technologies involved in different application scenarios. The Internet allows the integration of solutions to different problems, which benefits both users and companies. The Internet of Things is a further development of the Internet, which can further realize the interconnection of people, machines, and things. The work of this paper mainly focuses on the use of Internet of Things technology to achieve efficient management. A wireless device is designed in the paper, which can be integrated in a helmet. This helmet can be used in some… More >

Antonio Esposito¹, Marcello Lappa^2,*, Rocco Pagliara³, Gennaro Spada¹

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 189-203, 2022, DOI:10.32604/fdmp.2022.019605

Abstract The ability to measure the very high heat fluxes that typically occur during the hypersonic re-entry phase of space vehicles is generally considered a subject of great importance in the aerospace field. Most of the sensors used for these measurements need to be checked periodically and re-calibrated accordingly. Another bottleneck relates to the need to procure thermal sources that are able to generate reliable reference heat fluxes in the range between 100 and 1000 kW/m² (as order of magnitude). In the present study, a method is presented by which, starting from a calibration system with a capacity of approximately 500 kW/m² only,… More >

Xuewen Cao¹, Ni Xiong¹, Jian Li², Zhenqiang Xie¹, Xuerui Zang¹, Jiang Bian^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 233-241, 2022, DOI:10.32604/fdmp.2022.018505

Abstract The influence of the material stress state induced by internal and external forces on the erosion rate of pipelines has rarely been investigated in the literature. In order to fill this gap, using a tensile tester machine, a two–phase gas–solid particles jet erosion test was carried out considering a 316L stainless steel under different tensile stresses and different erosion angles. The results show that: 1) In the elastic range, with the increase of stress, the erosion rate manifests a rising trend; 2) In the metal plastic range, the increase of stress leads to a decrease of the erosion rate; 3)… More >

Yi Tu¹, Yu Zeng^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 355-370, 2022, DOI:10.32604/fdmp.2022.018423

Abstract Onboard air separation devices, based on hollow fiber membranes, are traditionally used for the optimization of aircraft fuel tank inerting systems. In the present study, a set of tests have been designed and executed to assess the air separation performances of these systems for different air inlet temperatures (70°C∼110°C), inlet pressures (0.1∼0.4 MPa), volume flow rates of nitrogen-enriched air (NEA) (30∼120 L/min) and flight altitudes (1.5∼18 km). In particular, the temperature, pressure, volume flow rate, and oxygen concentration of air, NEA and oxygen-enriched air (OEA) have been measured. The experimental results show that the oxygen concentration of NEA, air separation coefficient, and… More >

G. Boopathy^1,2,*, K. Gurusami¹, M. Chinnapandian³, K. R. Vijayakumar⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 223-232, 2022, DOI:10.32604/fdmp.2022.018225

Abstract In this research study, the mechanical properties of several Polymer matrix composites are investigated. These composites are multi-phase materials in which reinforcing materials are properly mixed with a polymer matrix. More precisely, Nylon 6 reinforced with 5, 15 and 25 wt. % of silicon carbide (SiC) and Nylon 6 reinforced with 5, 15 and 25 wt. % of boron carbide (B₄C), prepared by means of an injection moulding process at three different injection pressures are considered. Specific attention is paid to the tensile and impact strength of these composites. The Taguchi technique is used to optimize the process parameters such as reinforcement… More >

Yueli Feng^1,2, Yuetian Liu^1,2,*, Jian Chen^1,2, Xiaolong Mao^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 395-415, 2022, DOI:10.32604/fdmp.2022.018141

Abstract Stress sensitivity is a very important index to understand the seepage characteristics of a reservoir. In this study, dedicated experiments and theoretical arguments based on the visualization of porous media are used to assess the effects of the fracture angle, spacing, and relevant elastic parameters on the principal value of the permeability tensor. The fracture apertures at different angles show different change rates, which influence the relative permeability for different sets of fractures. Furthermore, under the same pressure condition, the fractures with different angles show different degrees of deformation so that the principal value direction of permeability rotates. This phenomenon… More >

Pengfei Ju^1,2,*, Mingrui Li^3,4, Jingying Wang^3,4

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 449-462, 2022, DOI:10.32604/fdmp.2022.018035

Abstract

Computational fluid dynamics (CFD) has become the main method for the prediction of the properties of the external wind environment in cities and other urban contexts. A review is presented of the existing literature in terms of boundary conditions, building models, computational domains, computational grids, and turbulence models. Some specific issues, such as the accuracy/computational cost ratio and the exploitation of existing empirical correlations, are also examined.

More >

Mingren Shao¹, Chunpeng Wang¹, Degui Wang¹, Wenbo Mei¹, Mingjie Li¹, Hao Yang^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 417-430, 2022, DOI:10.32604/fdmp.2022.018012

Abstract Detailed information is provided for the design and construction of nitrogen drilling in a coal seam. Two prototype wells are considered. The Guo model is used to calculate the required minimum gas injection rate, while the Finnie, Sommerfeld, and Tulsa models are exploited to estimate the ensuing erosion occurring in pipe strings. The calculated minimum gas injection rates are 67.4 m³/min (with water) and 49.4 m³/min (without water), and the actual field of use is 90–120 m³/min. The difference between the calculated injection pressure and the field value is 6.5%–15.2% (formation with water) and 0.65%–7.32% (formation without water). The results… More >

Zuoming Yin^1,*, Xuguang Wang², Desheng Wang¹, Zhiheng Dang¹, Jianfeng Shao³

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 257-269, 2022, DOI:10.32604/fdmp.2022.017915

Abstract The present study considers the so-called air deck blasting, one of the most commonly used techniques for the improvement of blasting efficiency in mining applications. In particular, it aims to improve the operating conditions of large-scale equipment, increase the efficiency of the slope enlarging process, and reduce the mining cost. These objectives are implemented through a two-fold approach where, first, a program for slope enlarging based on the middle air-deck charge blasting-loosening technology is proposed, and second, the physical mechanism responsible for the stress wave attenuation in the rock is analyzed in the framework of a Holmquist–Johnson–Cook constitutive model. Field… More >