Hijab Zahra¹, Wahaj Abbas Awan², Niamat Hussain^3,*, Syed Muzahir Abbas^1,4, Subhas Mukhopadhyay¹

CMC-Computers, Materials & Continua, Vol.70, No.1, pp. 1935-1944, 2022, DOI:10.32604/cmc.2022.019495 - 07 September 2021

Abstract This paper presents the design and characterization of a via free planar single turn helix for 28 GHz broadband applications. The proposed antenna is designed using ROGERS RO4003 material, having a simple structure and end-fire radiation pattern. The antenna comprises of a compact dimension of 1.36 λ₀ × 0.9 λ₀ with a thickness of 0.0189 λ₀ (where λ₀ is the free-space wavelength at the central frequency of 28 GHz). Parametric study has been carried out to investigate the impact of key design parameters and to achieve an optimum design. Results show a good agreement between the simulated… More >

Gagandeep Singh Walia¹, Parulpreet Singh¹, Manwinder Singh¹, Mohamed Abouhawwash^2,3, Hyung Ju Park⁴, Byeong-Gwon Kang^4,*, Shubham Mahajan⁵, Amit Kant Pandit⁵

CMC-Computers, Materials & Continua, Vol.70, No.1, pp. 305-321, 2022, DOI:10.32604/cmc.2022.019171 - 07 September 2021

Abstract Location information plays an important role in most of the applications in Wireless Sensor Network (WSN). Recently, many localization techniques have been proposed, while most of these deals with two Dimensional applications. Whereas, in Three Dimensional applications the task is complex and there are large variations in the altitude levels. In these 3D environments, the sensors are placed in mountains for tracking and deployed in air for monitoring pollution level. For such applications, 2D localization models are not reliable. Due to this, the design of 3D localization systems in WSNs faces new challenges. In this… More >

K. Gayathri Devi^*, R. S. Mishra, A. K. Madan

Intelligent Automation & Soft Computing, Vol.31, No.1, pp. 429-448, 2022, DOI:10.32604/iasc.2022.019330 - 03 September 2021

Abstract An NP-hard problem like Flexible Job Shop Scheduling (FJSP) tends to be more complex and requires more computational effort to optimize the objectives with contradictory measures. This paper aims to address the FJSP problem with combined and contradictory objectives, like minimization of make-span, maximum workload, and total workload. This paper proposes ‘Hybrid Adaptive Firefly Algorithm’ (HAdFA), a new enhanced version of the classic Firefly Algorithm (FA) embedded with adaptive parameters to optimize the multi objectives concurrently. The proposed algorithm has adopted two adaptive strategies, i.e., an adaptive randomization parameter (α) and an effective heterogeneous update More >

Mohammad Al Mojamed^*

Computer Systems Science and Engineering, Vol.40, No.1, pp. 259-272, 2022, DOI:10.32604/csse.2022.018458 - 26 August 2021

Abstract The Long-Range Wide Area Network (LoRaWAN) is one of the used communication systems that serve and enables the deployment of the Internet of Things (IoT), which occasionally transmit small size data. As part of the Low Power Wide Area Network (LPWAN), LoRaWAN is characterized by its ability for low power consumption. In addition, it is built to provide more extended coverage and higher capacity with minimum cost. In this paper, we investigate the feasibility and scalability of LoRaWAN for the Mina area using a realistic network model. Mina, known as the world’s largest tent city,… 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 - 27 July 2021

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… More > Graphic Abstract

Matt Ghiji^a,*, Ian Burch^b, Brigitta Suendermann^b, Grant Gamble^b, Vasily Novozhilov ^a, Paul Joseph^a, Khalid Moinuddin^a

Frontiers in Heat and Mass Transfer, Vol.17, pp. 1-8, 2021, DOI:10.5098/hmt.17.13

Abstract Lithium-ion batteries (LiBs) have superior energy density and lifetime compared to battery technologies such as lead acid. Despite the widespread application of LiBs in energy storage systems, electronic devices, aerospace and the automotive industry, they present a fire risk. In this study, experiments were conducted to characterize the thermal behavior of the electrolyte (as the main contributor to LiB fires) using a cone calorimeter; investigate the interactions of water mist and a Bunsen burner, as a precursor to examining the effectiveness of a water mist suppression system in extinguishing a LiB fire. In the present… More >

Liying Zhu^*, Ang Wang, Fang Jin

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1213-1222, 2021, DOI:10.32604/fdmp.2021.017572 - 08 September 2021

Abstract In the present study, the laws of smoke diffusion during forest fires are determined using the general principles of fluid mechanics and dedicated data obtained experimentally using an “ad hoc” imaging technology. Experimental images mimicking smoke in a real scenario are used to extract some “statistics”. These in turn are used to obtain the “divergence” of the flow (this fluid-dynamic parameter describing the amount of air that converges to a certain place from the surroundings or vice versa). The results show that the divergence of the smoke depends on the outside airflow and finally tends to More >

Yongheng Ku¹, Jinguang Zhang^2,3, Zhenyu Wang^3,4, Youxin Li^3,5, Haowei Yao^3,5,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1077-1090, 2021, DOI:10.32604/fdmp.2021.015779 - 08 September 2021

Abstract In order to study the extinguishing performance of high-pressure-water-mist-based systems on the fires originating from power transformers the PyroSim software is used. Different particle velocities and flow rates are considered. The evolution laws of temperature around transformer, flue gas concentration and upper layer temperature of flue gas are analyzed under different boundary conditions. It is shown that the higher the particle velocity is, the lower the smoke concentration is, the better the cooling effect on the upper layer temperature of flue gas layer is, the larger the flow rate is and the better the cooling More >

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 - 12 August 2021

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 More >

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 - 05 July 2021

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 >