Haolong Yang¹, Chunqiang Hu¹, Guwei Li^2,*, Jingchun Fan³

Computer Systems Science and Engineering, Vol.39, No.3, pp. 365-372, 2021, DOI:10.32604/csse.2021.016377

Abstract Despite the support of all kinds of fire prevention measures and high-tech fire prevention equipment, fires still occur frequently because of both anthropogenic factors and natural disasters. This issue has drawn the attention of schools, all levels of government, and other organizations. Many types of organizations carry out fire drills throughout the year. Because this kind of drill cannot anticipate the specific circumstances of each fire, which are generally far more complicated than drills, most people cannot correctly choose the optimal escape route from real fires. Thus, a fire-scene virtual simulation system based on the Dijkstra algorithm is here proposed… More >

Zhentao Chen¹, Weidong Lu^1,2,*, Yingwei Bao¹, Jun Zhang¹, Lu Wang¹, Kong Yue¹

Journal of Renewable Materials, Vol.10, No.1, pp. 89-104, 2022, DOI:10.32604/jrm.2021.015925

Abstract The timber-concrete composite (TCC) slabs have become a preferred choice of floor systems in modern multi story timber buildings. This TCC slab consisted of timber and a concrete slab which were commonly connected together with inclined self-tapping screws (STSs). To more accurately predict the fire performance of TCC slabs, the mechanical behavior of TCC connections under high temperature was investigated by numerical simulation in this study. The interface slip of TCC connections was simulated by a proposed Finite Element (FE) model at room temperature, and different diameter and penetration length screws were considered. The effectiveness of this FE model was… More > Graphic Abstract

Xiaojing Hou, Yongyou Cao^*, Wenfeng Mao, Zheng Wang, Jiwu Yuan

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.5, pp. 859-869, 2021, DOI:10.32604/fdmp.2021.015967

Abstract Two models are defined for predicting the trajectory of a foam jet originating from a fire monitor (hydrant) and the related intensity drop point. An experimental framework is also defined and used accordingly to compare real-time data with the predictions of such models. This mixed theoretical-experimental approach is proven to be effective for the determination of otherwise unknown coefficients which take into account several important factors such as the operation pressure, the elevation angle and the nozzle diameter. It is shown that the mean absolute error is smaller than 20%. More >

Liping Yu¹, Zhongyou Luo¹, Lifen Li¹, Xuedong Xi^2,3, Zhigang Wu^1,2,*, Bengang Zhang^4,*

Journal of Renewable Materials, Vol.9, No.12, pp. 2143-2157, 2021, DOI:10.32604/jrm.2021.016092

Abstract A flame retardant composition was prepared by using phosphoguanidine, guanidine sulfamate, disodium octaborate tetrahydrate and dodecyl dimethyl benzyl ammonium chloride. Veneers were immersed in such flame retardant mixture to prepare plywood. The combustion characteristics and thermal stability of plywood were assessed using a cone calorimeter and TG. Results showed that: (1) High concentration and loading of flame retardant were beneficial for the fire resistance of the plywood. (2) The limiting oxygen index (LOI) and residual mass of plywood processed using the flame retardant was increased by 87.52% and 58.66% compared to those of the untreated plywood, while the average heat… More >

Nataša Knez¹, Mirko Kariž², Friderik Knez¹, Nadir Ayrilmis^3,*, Manja Kitek Kuzman^2,*

Journal of Renewable Materials, Vol.9, No.11, pp. 1883-1895, 2021, DOI:10.32604/jrm.2021.016128

Abstract The effects of selected printing parameters on the fire properties of additively produced composites from neat polylactic acid (PLA) and wood/PLA filaments were investigated. The reaction to fire of the 3D-printed specimens was tested according to the ISO 5660-1 cone calorimeter test method. The results showed that the properties of the specimens when exposed to fire were significantly affected by the incorporation of wood flour into the PLA filament. It was also interesting that PLA specimens had much better reactions to fire than the wood/PLA specimens. Time to ignition was found to be much longer in the 3D-printed PLA specimens.… More >

Abdul Majid¹, Muhammad Attique Khan¹, Yunyoung Nam^2,*, Usman Tariq³, Sudipta Roy⁴, Reham R. Mostafa⁵, Rasha H. Sakr⁶

CMC-Computers, Materials & Continua, Vol.69, No.1, pp. 319-337, 2021, DOI:10.32604/cmc.2021.016816

Abstract The recent COVID-19 pandemic caused by the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has had a significant impact on human life and the economy around the world. A reverse transcription polymerase chain reaction (RT-PCR) test is used to screen for this disease, but its low sensitivity means that it is not sufficient for early detection and treatment. As RT-PCR is a time-consuming procedure, there is interest in the introduction of automated techniques for diagnosis. Deep learning has a key role to play in the field of medical imaging. The most important issue in this area is the… More >

Hashem Alyami¹, Mohd Faizan², Wael Alosaimi³, Abdullah Alharbi³, Abhishek Kumar Pandey², Md Tarique Jamal Ansari⁴, Alka Agrawal², Raees Ahmad Khan^2,*

Computer Systems Science and Engineering, Vol.38, No.2, pp. 141-149, 2021, DOI:10.32604/csse.2021.017039

Abstract The ubiquitous nature of the internet has made it easier for criminals to carry out illegal activities online. The sale of illegal firearms and weaponry on dark web cryptomarkets is one such example of it. To aid the law enforcement agencies in curbing the illicit trade of firearms on cryptomarkets, this paper has proposed an automated technique employing ensemble machine learning models to detect the firearms listings on cryptomarkets. In this work, we have used part-of-speech (PoS) tagged features in conjunction with n-gram models to construct the feature set for the ensemble model. We studied the effectiveness of the proposed… More >

Samer H. Atawneh¹, Waqar A. Khan², Nawaf N. Hamadneh^3,*, Adeeb M. Alhomoud³

CMC-Computers, Materials & Continua, Vol.67, No.1, pp. 73-87, 2021, DOI:10.32604/cmc.2021.012351

Abstract The objectives of this study involve the optimization of longitudinal porous fins of square cross-section using metaheuristic algorithms. A generalized nonlinear ordinary differential equation is derived using Darcy and Fourier’s laws in the energy balance around a control volume and is solved numerically using RFK 45 method. The temperature of the base surface is higher than the fin surface, and the fin tip is kept adiabatic or cooled by convection heat transfer. The other pertinent parameters include Rayleigh number (100 ≤ Ra ≤ 10⁴), Darcy number, (10⁻⁴ ≤ Da ≤ 10⁻²), relative thermal conductivity ratio of solid phase to fluid (1000 ≤ k_r ≤ 8000), Nusselt number (10 ≤ Nu ≤ 100), porosity (0.1 ≤ φ ≤ 0.9).… More >

Yu Xue, Sow Alpha Amadou^*, Yan Zhao

Journal of Cyber Security, Vol.2, No.4, pp. 191-196, 2020, DOI:10.32604/jcs.2020.014045

Abstract Attracted numerous analysts’ consideration, classification is one of the primary issues in Machine learning. Numerous evolutionary algorithms (EAs) were utilized to improve their global search ability. In the previous years, many scientists have attempted to tackle this issue, yet regardless of the endeavors, there are still a few inadequacies. Based on solving the classification problem, this paper introduces a new optimization classification model, which can be applied to the majority of evolutionary computing (EC) techniques. Firework algorithm (FWA) is one of the EC methods, Although the Firework algorithm (FWA) is a proficient algorithm for solving complex optimization issue. The proficient… More >

Li Lei^*, Wukai Chen, Huiling Li, Shuai Shi

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 837-856, 2020, DOI:10.32604/fdmp.2020.09631

Abstract Urban tunnels are generally narrow and fire smoke can hardly diffuse. In the present study, numerical simulation is used to analyze the diffusion of high temperature smoke produced by fire inside a specific tunnel (the Kaiyuan tunnel). The results are compared with similar data relating to other tests to determine the validity of the numerical method. Moreover, the critical velocity obtained by numerical simulation of 5 MW, 20 MW, and 50 MW fires in curved and linear sections of the considered tunnel is compared with the values obtained using empirical formulas. The results show that, for the tunnel ventilation design,… More >