Jianxin Hu, Xin Huang, Yuzhen Jin^*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.3, pp. 597-614, 2021, DOI:10.32604/fdmp.2021.014249 - 29 April 2021

Abstract By studying the characteristics of the flow field around a swimming fish, useful insights can be obtained into the superior swimming capabilities developed by nature over millions of years, in comparison to what can be achieved using the standard engineering principles traditionally employed in naval and ocean engineering. In the present study, the flow field related to a single joint fish model is simulated in the framework of a commercial computational fluid dynamics software (ANSYS Fluent 18.0). The principle of the anti-Kármán vortex street is analyzed and the relationship between the direction of the tail 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 >

Hegazy Rezk^1,2, Irik Z. Mukhametzyanov³, Mujahed Al-Dhaifallah^4,*, Hamdy A. Ziedan⁵

CMC-Computers, Materials & Continua, Vol.68, No.2, pp. 2001-2027, 2021, DOI:10.32604/cmc.2021.015895 - 13 April 2021

Abstract Several models of multi-criteria decision-making (MCDM) have identified the optimal alternative electrical energy sources to supply certain load in an isolated region in Al-Minya City, Egypt. The load demand consists of water pumping system with a water desalination unit. Various options containing three different power sources: only DG, PV-B system, and hybrid PV-DG-B, two different sizes of reverse osmosis (RO) units; RO-250 and RO-500, two strategies of energy management; load following (LF) and cycle charging (CC), and two sizes of DG; 5 and 10 kW were taken into account. Eight attributes, including operating cost, renewable… More >

Ibrahim M. Almanjahie^1,2, Amer Ibrahim Al-Omari^3,*, Emmanuel J. Ekpenyong⁴, Mir Subzar⁵

Computer Systems Science and Engineering, Vol.38, No.1, pp. 1-15, 2021, DOI:10.32604/csse.2021.015933 - 01 April 2021

Abstract In estimation theory, the researchers have put their efforts to develop some estimators of population mean which may give more precise results when adopting ordinary least squares (OLS) method or robust regression techniques for estimating regression coefficients. But when the correlation is negative and the outliers are presented, the results can be distorted and the OLS-type estimators may give misleading estimates or highly biased estimates. Hence, this paper mainly focuses on such issues through the use of non-conventional measures of dispersion and a robust estimation method. Precisely, we have proposed generalized estimators by using the… More >

Bassm H. Abed¹, Jaber H. Majeed^1,*, Najma Abed Habeeb²

Computer Systems Science and Engineering, Vol.38, No.1, pp. 17-24, 2021, DOI:10.32604/csse.2021.015544 - 01 April 2021

Abstract Recently, the inductive coupling link is the most robust method for powering implanted biomedical devices, such as micro-system stimulators, cochlear implants, and retinal implants. This research provides a novel theoretical and mathematical analysis to optimize the inductive coupling link efficiency driven by efficient proposed class-E power amplifiers using high and optimum input impedance. The design of the coupling link is based on two pairs of aligned, single-layer, planar spiral circular coils with a proposed geometric dimension, operating at a resonant frequency of 13.56 MHz. Both transmitter and receiver coils are small in size. Implanted device More >

Jaime Francisco de Sousa Resende^1,*, Andrea Lucia Teixeira Charbel², Teresa Cristina Bessa Nogueira Assunção³

Energy Engineering, Vol.118, No.3, pp. 615-629, 2021, DOI:10.32604/EE.2021.014588 - 22 March 2021

Abstract Buildings represent a significant share of the world’s energy consumption, and the sector has drawn the attention of governments, which have adopted policies to reduce energy expenditure. The Certifications of Energy Efficiency in Buildings stand out as one possible solution to achieve this goal, employed in several countries worldwide. The European Union presents advanced energy assessment programs for buildings, being a reference and model for several other regulations in the world. The Energy Certification System for Buildings (SCE) of Portugal is considered a success case, reflected in the significant number of energy certificates issued. The… More >

Surajo Muhammad^1,*, Jun Jiat Tiang¹, Sew Kin Wong¹, Amjad Iqbal¹, Amor Smida², Mohamed Karim Azizi³

CMC-Computers, Materials & Continua, Vol.68, No.1, pp. 167-184, 2021, DOI:10.32604/cmc.2021.016133 - 22 March 2021

Abstract This paper presents a compact multi-band rectifier with an improved impedance matching bandwidth. It uses a combination of п–matching network (MN) at Port-1, with a parallel connection of three cell branch MN at Port-2. The proposed impedance matching network (IMN) is adopted to reduce circuit complexity, to improve circuit performance, and power conversion efficiency (PCE) of the rectifier at low input power. The fabricated rectifier prototype operates at 0.92, 1.82, 2.1, 2.46 and 2.65 GHz covering GSM/900, GSM/1800, UMTS2100, and Wi-Fi/2.45–LTE2600. The size of the compact rectifier on the PCB board is 0.13λ_g × 0.1λ_g. The… More >

Rana Zeeshan Ahamad¹, Abdul Rehman Javed^2,*, Shakir Mehmood³, Mohammad Zubair Khan⁴, Abdulfattah Noorwali⁵, Muhammad Rizwan⁶

CMC-Computers, Materials & Continua, Vol.68, No.1, pp. 45-58, 2021, DOI:10.32604/cmc.2021.016082 - 22 March 2021

Abstract Device to Device (D2D) communication is emerging as a new participant promising technology in 5G cellular networks to promote green energy networks. D2D communication can improve communication delays, spectral efficiency, system capacity, data off-loading, and many other fruitful scenarios where D2D can be implemented. Nevertheless, induction of D2D communication in reuse mode with the conventional cellular network can cause severe interference issues, which can significantly degrade network performance. To reap all the benefits of induction of D2D communication with conventional cellular communication, it is imperative to minimize interference’s detrimental effects. Efficient power control can minimize More >

Krishnan Muthumayil^1,*, Thangaiyan Jayasankar², Nagappan Krishnaraj³, Mohamed Yacin Sikkandar⁴, Prakash Nattanmai Balasubramanian⁵, Chokkalingam Bharatiraja⁶

Intelligent Automation & Soft Computing, Vol.27, No.3, pp. 771-784, 2021, DOI:10.32604/iasc.2021.012462 - 01 March 2021

Abstract Wireless Multimedia Sensor Networks (WMSN) provides valuable information for scalar data, images, audio, and video processing in monitoring and surveillance applications. Multimedia streaming, however, is highly challenging for networks as energy restriction sensor nodes limit the potential data transmission bandwidth and lead to reduced throughput. WMSN’s two key design challenges, which can be achieved by the clustering process, are energy efficiency and throughput maximization. The use of the clustering technique helps to organise the sensor nodes into clusters, and between each cluster a cluster head (CH) will be chosen. This paper introduces a new Artificial… More >

Maryam Shafiq¹, Humaira Ashraf¹, Ata Ullah², Mehedi Masud³, Muhammad Azeem², N. Z. Jhanjhi^4,*, Mamoona Humayun⁵

CMC-Computers, Materials & Continua, Vol.67, No.3, pp. 3505-3521, 2021, DOI:10.32604/cmc.2021.015533 - 01 March 2021

Abstract The Internet of Things (IoT) is gaining attention because of its broad applicability, especially by integrating smart devices for massive communication during sensing tasks. IoT-assisted Wireless Sensor Networks (WSN) are suitable for various applications like industrial monitoring, agriculture, and transportation. In this regard, routing is challenging to find an efficient path using smart devices for transmitting the packets towards big data repositories while ensuring efficient energy utilization. This paper presents the Robust Cluster Based Routing Protocol (RCBRP) to identify the routing paths where less energy is consumed to enhances the network lifespan. The scheme is… More >