Lixiang Dang¹, Yanwen Zeng¹, Wei Duan^1,*, Yan Zhang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.29, No.2, pp. 1-1, 2024, DOI:10.32604/icces.2024.012173

Abstract In order to regulate the multi-scale structure of Ti-6Al-4V formed by the SLM (selective laser melting) process, this study uses the method of combining numerical simulations with experiments to investigate the effects of SLM process parameters on the phase composition, micro- and meso-structures, and their distribution of Ti-6Al-4V. The study shows that the SLM-formed Ti-6Al-4V is mainly composed of α/α' phases. Horizontally, the specimens at a 0° phase angle mainly show a striped pattern, while the specimens at 67° and 90° phase angles will show a tessellated pattern. Vertically, the specimens at 0°, 67°, and More >

Xiaohong Wang, Huiqing Wu, Yuying Ma, Shuzhen Huang^*

Computer Systems Science and Engineering, Vol.46, No.1, pp. 1093-1108, 2023, DOI:10.32604/csse.2023.036652 - 20 January 2023

Abstract With the rapid development of 5G technology, it has become fast and easy for people to transmit information on the Internet. Digital images can express information more intuitively, so transmitting information through images has excellent applications. This paper uses a new chaotic system called 1D-Sin-Logistic-Map (1D-SLM). 1D-SLM has two control parameters, which can provide larger parameter space, and the parameter space in the chaotic state is continuous. Through Lyapunov exponent analysis (LE), bifurcation diagrams analysis, spectral entropy analysis (SE), and 0-1 test, it is verified that 1D-SLM has complex dynamic behavior and is very suitable More >

Akku Madhusudhan^*, Sudhir Kumar Sharma

Intelligent Automation & Soft Computing, Vol.36, No.2, pp. 1273-1282, 2023, DOI:10.32604/iasc.2023.030765 - 05 January 2023

Abstract The next step in mobile communication technology, known as 5G, is set to go live in a number of countries in the near future. New wireless applications have high data rates and mobility requirements, which have posed a challenge to mobile communication technology researchers and designers. 5G systems could benefit from the Universal Filtered Multicarrier (UFMC). UFMC is an alternate waveform to orthogonal frequency-division multiplexing (OFDM), in filtering process is performed for a sub-band of subcarriers rather than the entire band of subcarriers Inter Carrier Interference (ICI) between neighbouring users is reduced via the sub-band More >

Himanshu Sharma¹, karthikeyan Rajagopal², G. Gugapriya³, Rajneesh Pareek¹, Arun Kumar⁴, Haya Mesfer Alshahrani⁵, Mohamed K. Nour⁶, Hany Mahgoub⁷, Mohamed Mousa⁸, Anwer Mustafa Hilal^9,*

Computer Systems Science and Engineering, Vol.45, No.2, pp. 1199-1210, 2023, DOI:10.32604/csse.2023.030909 - 03 November 2022

Abstract Multicarrier Waveform (MCW) has several advantages and plays a very important role in cellular systems. Fifth generation (5G) MCW such as Non-Orthogonal Multiple Access (NOMA) and Filter Bank Multicarrier (FBMC) are thought to be important in 5G implementation. High Peak to Average Power Ratio (PAPR) is seen as a serious concern in MCW since it reduces the efficiency of amplifier use in the user devices. The paper presents a novel Divergence Selective Mapping (DSLM) and Divergence Partial Transmission Sequence (D-PTS) for 5G waveforms. It is seen that the proposed D-SLM and PTS lower PAPR with More >

Rajneesh Pareek¹, Karthikeyan Rajagopal², Himanshu Sharma¹, Nidhi Gour¹, Arun Kumar³, Sami Althahabi⁴, Haya Mesfer Alshahrani⁵, Mohamed Mousa⁶, Manar Ahmed Hamza^7,*

CMC-Computers, Materials & Continua, Vol.73, No.1, pp. 1637-1648, 2022, DOI:10.32604/cmc.2022.029563 - 18 May 2022

Abstract Multi and single carrier waveforms are utilized in cellular systems for high-speed data transmission. In The Fifth Generation (5G) system, several waveform techniques based on multi carrier waveforms are proposed. However, the Peak to Average Power Ratio (PAPR) is seen as one of the significant concerns in advanced waveforms as it degrades the efficiency of the framework. The proposed article documents the study, progress, and implementation of PAPR reduction algorithms for the 5G radio framework. We compare the PAPR algorithm performance for advanced and conventional waveforms. The simulation results reveal that the advanced Partial Transmission More >

Himanshu Sharma¹, Nidhi Gour¹, Sumit Chakravarty², Fahad Alraddady³, Mehedi Masud⁴, Rajneesh Pareek¹, Arun Kumar^5,*

Intelligent Automation & Soft Computing, Vol.34, No.2, pp. 1367-1375, 2022, DOI:10.32604/iasc.2022.025655 - 03 May 2022

Abstract Cellular systems utilize single and multicarrier waveforms for high-speed data transmission. The Fifth-Generation (5G) system proposes several techniques based on multicarrier waveforms. However, the Peak to Average Power Ratio (PAPR) is one of the significant concerns in advanced waveforms as it degrades the framework's efficiency. Non Orthogonal Multiple Access (NOMA) can provide massive connectivity, which is the crucial requirement of the Internet of Things (IoT). The 3^rd generation tested NOMA applications in downlink and uplink transmission. However, NOMA uplink transmission in the power domain has performance degradation and is not considered a possible technique in 3^rd… More >

Arun Kumar^1,*, Sivabalan Ambigapathy², Mehedi Masud³, Emad Sami Jaha⁴, Sumit Chakravarty⁵, Kanchan Sengar¹

CMC-Computers, Materials & Continua, Vol.69, No.3, pp. 2967-2981, 2021, DOI:10.32604/cmc.2021.019092 - 24 August 2021

Abstract The article introduces Non-Orthogonal Multiple Access (NOMA) and Filter Bank Multicarrier (FBMC), known as hybrid waveform (NOMA-FBMC), as two of the most deserving contenders for fifth-generation (5G) network. High spectrum access and clampdown of spectrum outflow are unique characteristics of hybrid NOMA-FBMC. We compare the spectral efficiency of Orthogonal Frequency Division Multiplexing (OFDM), FBMC, NOMA, and NOMA-FBMC. It is seen that the hybrid waveform outperforms the existing waveforms. Peak to Average Power Ratio (PAPR) is regarded as a significant issue in multicarrier waveforms. The combination of Selective Mapping-Partial Transmit Sequence (SLM-PTS) is an effective way More >

Mohit Kumar Sharma, Arun Kumar^*

CMC-Computers, Materials & Continua, Vol.69, No.1, pp. 1391-1406, 2021, DOI:10.32604/cmc.2021.017666 - 04 June 2021

Abstract Non-orthogonal multiple access (NOMA) is gaining considerable attention due to its features, such as low out-of-band radiation, signal detection capability, high spectrum gain, fast data rate, and massive D2D connectivity. It may be considered for 5G networks. However, the high peak-to-average power ratio (PAPR) is viewed as a significant disadvantage of a NOMA waveform, and it weakens the quality of signals and the throughput of the scheme. In this article, we introduce a modified NOMA system by employing a block of wavelet transform, an alternative to FFT (Fast Fourier transform). The modified system combines the More >

Jin Zhang¹, Youliang Tang¹, Feng Yu^2,*

Energy Engineering, Vol.118, No.4, pp. 1083-1094, 2021, DOI:10.32604/EE.2021.014482 - 31 May 2021

Abstract In this paper, position sensorless control system of permanent magnet synchronous linear motor (PMSLM) based on sliding mode observer (SMO) with an improved phase-locked loop (PLL) is studied. Firstly, according to the mathematical model, a SMO is designed for sensorless control PMSLM drive. Thereafter, an improved PLL is proposed to tackle the imperfection of data overflow existed in the traditional PLL. The designed SMO incorporating with the improved PLL can be effectively suppress the pulsation of the estimated position and hence the chattering of the derived electrical angular velocity. At last, simulated and experimental results More >

Kang-Hyun Lee¹, Gun Jin Yun^1,2,*

CMC-Computers, Materials & Continua, Vol.66, No.1, pp. 87-112, 2021, DOI:10.32604/cmc.2020.012688 - 30 October 2020

Abstract Re-melting process has been utilized to mitigate the residual stress level in the selective laser melting (SLM) process in recent years. However, the complex consolidation mechanism of powder and the different material behavior after the first laser melting hinder the direct implementation of the re-melting process. In this work, the effects of re-melting on the temperature and residual stress evolution in the SLM process are investigated using a thermo-mechanically coupled finite element model. The degree of consolidation is incorporated in the energy balance equation based on the thermodynamically-consistent phase-field approach. The drastic change of material… More >