Bachir Melzi¹, Nesrine Kefif², Mamdouh El Haj Assad^3,*, Haleh Delnava⁴, Abdulkadir Hamid⁵

Energy Engineering, Vol.118, No.6, pp. 1767-1781, 2021, DOI:10.32604/EE.2021.017270 - 10 September 2021

Abstract This work presents a hybrid power system consisting of photovoltaic and solid oxide fuel cell (PV-SOFC) for electricity production and hydrogen production. The simulation of this hybrid system is adjusted for Bou-Zedjar city in north Algeria. Homer software was used for this simulation to calculate the power output and the total net present cost. The method used depends on the annual average monthly values of clearness index and radiation for which the energy contributions are determined for each component of PV/SOFC hybrid system. The economic study is more important criterion in the proposed hybrid system, More >

Xin Xu^*, Lian Zhang^*

Energy Engineering, Vol.118, No.6, pp. 1905-1920, 2021, DOI:10.32604/EE.2021.016738 - 10 September 2021

Abstract This paper briefly summarizes the current status of typical solar thermal power plant system, including system composition, thermal energy storage medium and performance. The thermo-physical properties of the storage medium are some of the most important factors that affect overall efficiency of the system, because some renewable energy sources such as solar and wind are unpredictable. A thermal storage system is therefore necessary to store energy for continuous usage. Based on the form of storage or the mode of system connection, heat exchangers of a thermal storage system can produce different temperature ranges of heat… More >

Xiyang Li^1,2, Bin Cheng^1,2, Hui Zhang^1,2,*, Xianghan Zhang¹, Zhi Yun¹

Energy Engineering, Vol.118, No.6, pp. 1869-1886, 2021, DOI:10.32604/EE.2021.015542 - 10 September 2021

Abstract With the continuous increase in the proportional use of wind energy across the globe, the reduction of power generation efficiency and safety hazards caused by the icing on wind turbine blades have attracted more consideration for research. Therefore, it is crucial to accurately analyze the thickness of icing on wind turbine blades, which can serve as a basis for formulating corresponding control measures and ensure a safe and stable operation of wind turbines in winter times and/or in high altitude areas. This paper fully utilized the advantages of the support vector machine (SVM) and back-propagation More >

Xiaojuan Lu, Qingbo Zhang^*

Energy Engineering, Vol.118, No.6, pp. 1729-1740, 2021, DOI:10.32604/EE.2021.014938 - 10 September 2021

Abstract In the process of grid-connected photovoltaic power generation, there are high requirements for the quality of the power that the inverter breaks into the grid. In this work, to improve the power quality of the grid-connected inverter into the grid, and the output of the system can meet the grid-connected requirements more quickly and accurately, we exhibit an approach toward establishing a mixed logical dynamical (MLD) model where logic variables were introduced to switch dynamics of the single-phase photovoltaic inverters. Besides, based on the model, our recent efforts in studying the finite control set model More >

Hanyu Shi¹, Weiguang Qu^1,2,*, Tingxin Wei^2,3, Junsheng Zhou¹, Yunfei Long⁴, Yanhui Gu¹, Bin Li²

CMC-Computers, Materials & Continua, Vol.69, No.3, pp. 4113-4127, 2021, DOI:10.32604/cmc.2021.019518 - 24 August 2021

Abstract In Mandarin Chinese, when the noun head appears in the context, a quantity noun phrase can be reduced to a quantity phrase with the noun head omitted. This phrase structure is called elliptical quantity noun phrase. The automatic recovery of elliptical quantity noun phrase is crucial in syntactic parsing, semantic representation and other downstream tasks. In this paper, we propose a hybrid neural network model to identify the semantic category for elliptical quantity noun phrases and realize the recovery of omitted semantics by supplementing concept categories. Firstly, we use BERT to generate character-level vectors. Secondly,… 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 >

Ziadoon K. Maseer¹, Robiah Yusof¹, Salama A. Mostafa^2,*, Nazrulazhar Bahaman¹, Omar Musa³, Bander Ali Saleh Al-rimy⁴

CMC-Computers, Materials & Continua, Vol.69, No.3, pp. 3945-3966, 2021, DOI:10.32604/cmc.2021.016074 - 24 August 2021

Abstract With an increasing number of services connected to the internet, including cloud computing and Internet of Things (IoT) systems, the prevention of cyberattacks has become more challenging due to the high dimensionality of the network traffic data and access points. Recently, researchers have suggested deep learning (DL) algorithms to define intrusion features through training empirical data and learning anomaly patterns of attacks. However, due to the high dynamics and imbalanced nature of the data, the existing DL classifiers are not completely effective at distinguishing between abnormal and normal behavior line connections for modern networks. Therefore,… More >

Heming Jia^1,2,*, Yao Li², Kangjian Sun², Ning Cao¹, Helen Min Zhou³

Computer Systems Science and Engineering, Vol.39, No.3, pp. 321-335, 2021, DOI:10.32604/csse.2021.017536 - 12 August 2021

Abstract In this paper, a hybrid model based on sooty tern optimization algorithm (STOA) is proposed to optimize the parameters of the support vector machine (SVM) and identify the best feature sets simultaneously. Feature selection is an essential process of data preprocessing, and it aims to find the most relevant subset of features. In recent years, it has been applied in many practical domains of intelligent systems. The application of SVM in many fields has proved its effectiveness in classification tasks of various types. Its performance is mainly determined by the kernel type and its parameters.… More >

Liping Yan^1,*, Wei-Chiang Hong²

CMES-Computer Modeling in Engineering & Sciences, Vol.128, No.3, pp. 1069-1102, 2021, DOI:10.32604/cmes.2021.016499 - 11 August 2021

Abstract The timely and effective investment risk assessment and forecasting are of great significance to ensure the investment safety and sustainable development of wind energy along the Belt and Road. In order to obtain the scientific and real-time forecasting result, this paper constructs a novel hybrid intelligent model based on improved cloud model combined with GRA-TOPSIS and MBA-WLSSVM. Firstly, the factors influencing investment risk of wind energy along the Belt and Road are identified from three dimensions: endogenous risk, exogenous risk and process risk. Through the fuzzy threshold method, the final input index system is selected.… More >

Ke Song^1,*, Paul Liu², Dongquan Liu³

CMES-Computer Modeling in Engineering & Sciences, Vol.128, No.3, pp. 1133-1150, 2021, DOI:10.32604/cmes.2021.016008 - 11 August 2021

Abstract A novel beamforming algorithm named Delay Multiply and Sum (DMAS), which excels at enhancing the resolution and contrast of ultrasonic image, has recently been proposed. However, there are nested loops in this algorithm, so the calculation complexity is higher compared to the Delay and Sum (DAS) beamformer which is widely used in industry. Thus, we proposed a simple vector-based method to lower its complexity. The key point is to transform the nested loops into several vector operations, which can be efficiently implemented on many parallel platforms, such as Graphics Processing Units (GPUs), and multi-core Central… More >