Qasem M. Kharma^*, Abdelrahman H. Hussein, Faris M. Taweel, Mosleh M. Abualhaj, Qusai Y. Shambour

Intelligent Automation & Soft Computing, Vol.31, No.2, pp. 869-883, 2022, DOI:10.32604/iasc.2022.020415 - 22 September 2021

Abstract The widespread and desirable features of IP and IEEE 802.11 networks have made these technologies a suitable medium for carrying voice over IP (VoIP). However, a bandwidth (BW) exploitation obstacle emerges when 802.11 networks are used to carry VoIP traffic. This BW exploitation obstacle is caused by the large 80-byte preamble size of the VoIP packet and a waiting time of 765 μs for each layer 2 VoIP frame. As a solution, IEEE 802.11n was consequently designed with a built-in layer 2 frame aggregation feature, but the adverse impact on the VoIP performance still needed More >

Junxiang Jiang^1,2, Shaogang Liu^1,*, Lifeng Feng³

Energy Engineering, Vol.118, No.5, pp. 1287-1303, 2021, DOI:10.32604/EE.2021.015354 - 16 July 2021

Abstract This paper presents a 2DOF nonlinear piezoelectric energy harvester for improving the efficiency of energy harvesting in low frequency range. The device consisted of an L-shaped piezoelectric cantilever with a magnet at the tip of the first beam and two external magnets on the pedestal. The distance between the magnets which generated nonlinear magnetic attraction was adjusted such that the system can exhibit monostable or bistable characteristics. First, the model of this piezoelectric energy harvester was established and the dynamic equation was derived based on the magnetic attractive force. Then, the nonlinear dynamic responses of More >

Shahid Khan^1,*, Xin Cheng Ren², Haider Ali³, Camel Tanougast¹, Abdul Rauf⁴, Safdar Nawaz Khan Marwat⁵, Muhammad Rizwan Anjum⁶

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 2095-2109, 2021, DOI:10.32604/cmc.2021.016811 - 13 April 2021

Abstract In this work, a novel compact wideband reconfigurable circularly polarised (CP) dielectric resonator antenna (DRA) is presented. The L-shaped Dielectric resonator antenna is excited by an inverted question mark shaped feed. This arrangement of feed-line helps to generate two orthogonal modes inside the DR, which makes the design circularly polarised. A thin micro-strip line placed on the defected ground plane not only helps to generate a wideband response but also assist in the positioning of the two diode switches. These switches located at the left and right of the micro-strip line helps in performing two… More >

Mosleh M. Abualhaj^*, Qusai Y. Shambour, Abdelrahman H. Hussein, Qasem M. Kharma

CMC-Computers, Materials & Continua, Vol.68, No.1, pp. 1271-1283, 2021, DOI:10.32604/cmc.2021.014928 - 22 March 2021

Abstract Voice over Internet Protocol (VoIP) is widely used by companies, schools, universities, and other institutions. However, VoIP faces many issues that slow down its propagation. An important issue is poor utilization of the VoIP service network bandwidth, which results from the large header of the VoIP packet. The objective of this study is to handle this poor utilization of the network bandwidth. Therefore, this study proposes a novel method to address this large header overhead problem. The proposed method is called zero size payload (ZSP), which aims to reemploy and use the header information (fields) More >

Mosleh M. Abualhaj^1,*, Abdelrahman H. Hussein¹, Manjur Kolhar², Mwaffaq Abu AlHija¹

CMC-Computers, Materials & Continua, Vol.66, No.2, pp. 1283-1300, 2021, DOI:10.32604/cmc.2020.012991 - 26 November 2020

Abstract The IEEE 802.11n standard has provided prominent features that greatly contribute to ubiquitous wireless networks. Over the last ten years, voice over IP (VoIP) has become widespread around the globe owing to its low-cost or even free call rate. The combination of these technologies (VoIP and wireless) has become desirable and inevitable for organizations. However, VoIP faces a bandwidth utilization issue when working with 802.11 wireless networks. The bandwidth utilization is inefficient on the grounds that (i) 80 bytes of 802.11/RTP/UDP/IP header is appended to 10–730 bytes of VoIP payload and (ii) 765 µs waiting… More >

Qixue Guan^*, Yueqiu Jiang

Intelligent Automation & Soft Computing, Vol.26, No.4, pp. 773-781, 2020, DOI:10.32604/iasc.2020.010112

Abstract It is known that congestion in the reverse direction happens in advance of the congestion in the forward direction due to the significant bandwidth asymmetry in the two directions of the space networks, especially in the satellite networks, which enables the TCP Vegas to enter the phase of the congestion avoidance blindly and reduce the throughput of the forward direction. To solve this problem, a congestion control model, TCP Vegas-DDA, which maintains the frequency of the acknowledgments in the reverse direction is proposed. The model sets the interval time between acknowledgments dynamically based on the More >

Minjae Seo¹, Jong-Ho Paik^{2, *}

CMC-Computers, Materials & Continua, Vol.65, No.3, pp. 2571-2589, 2020, DOI:10.32604/cmc.2020.011347 - 16 September 2020

Abstract The trend in video viewing has been evolving beyond simply providing a multiview option. Recently, a function that allows selection and viewing of a clip from a multiview service that captures a specific range or object has been added. In particular, the freeview service is an extended concept of multi-view and provides a freer viewpoint. However, since numerous videos and additional data are required for its construction, all of the clips constituting the content cannot be simultaneously provided. Only certain clips are selected and provided to the user. If the video is not the preferred… More >

Muhammad Abdullah^1,*, Saad Ahmad Khan¹, Mamdouh Alenez², Khaled Almustafa³, Waheed Iqbal¹

Intelligent Automation & Soft Computing, Vol.26, No.1, pp. 13-25, 2020, DOI:10.31209/2018.100000047

Abstract An efficient placement of virtual machines (VMs) in a cloud datacenter is important to maximize the utilization of infrastructure. Most of the existing work maximises the number of VMs to place on a minimum number of physical machines (PMs) to reduce energy consumption. Recently, big data applications become popular which are mostly hosted on cloud datacenters. Big data applications are deployed on multiple VMs and considered data and communication intensive applications. These applications can consume most of the datacenter bandwidth if VMs do not place close to each other. In this paper, we investigate the More >

Geetha N., Sankar A.

Intelligent Automation & Soft Computing, Vol.24, No.4, pp. 711-719, 2018, DOI:10.1080/10798587.2017.1309003

Abstract The routing protocol for an ad hoc network should be efficient in utilizing the available resources to prolong the network lifetime. A Multi Criterion Fuzzy based Energy Efficient Routing Protocol (MCFEER) for Ad hoc Networks selects the path on constraints like bandwidth, battery life, hop count and buffer occupancy. In the route discovery phase, fuzzy system is applied for optimal route selection by destination node leading to successful data transmission. Multiple stable paths are preserved in route cache for usage during the route maintenance phase. The results are competitive when compared with Power aware Energy More >

CMC-Computers, Materials & Continua, Vol.52, No.2, pp. 123-131, 2016, DOI:10.3970/cmc.2016.052.123

Abstract In this paper, the gyrotropic bi-anisotropy of the chiral medium in substrate constitutive parameters (xc and hc) of a rectangular microstrip patch antenna is introduced in order to observe its effects on the complex resonant frequency and half-power bandwidth. The analysis is based on the full-wave spectral domain approach using the Moment Method, with sinusoidal type basis functions. The numerical calculations related to the dominant mode have been carried out, and it has been observed that the resonant frequency and the bandwidth are directly linked to the medium chirality. The new results can be considered More >