Junqi Guo^1,2, Qingyun Xiong^1,*, Minghui Yang¹, Ziyun Zhao¹

CMC-Computers, Materials & Continua, Vol.76, No.1, pp. 827-848, 2023, DOI:10.32604/cmc.2023.036450

Abstract Nowadays, smart wearable devices are used widely in the Social Internet of Things (IoT), which record human physiological data in real time. To protect the data privacy of smart devices, researchers pay more attention to federated learning. Although the data leakage problem is somewhat solved, a new challenge has emerged. Asynchronous federated learning shortens the convergence time, while it has time delay and data heterogeneity problems. Both of the two problems harm the accuracy. To overcome these issues, we propose an asynchronous federated learning scheme based on double compensation to solve the problem of time delay and data heterogeneity problems.… More >

Jikang Xu^1,4, Ruichuan Li^1,2,*, Yi Cheng², Yanchao Li³, Junru Yang³, Chenyu Feng⁴, Xinkai Ding², Huazhong Zhang⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.7, pp. 1817-1836, 2023, DOI:10.32604/fdmp.2023.022602

Abstract Electro-hydraulic proportional valve is the core control valve in many hydraulic systems used in agricultural and engineering machinery. To address the problem related to the large throttling losses and poor stability typically associated with these valves, here, the beneficial effects of a triangular groove structure on the related hydraulic response are studied. A mathematical model of the pressure compensation system based on the power-bond graph method is introduced, and the AMESim software is used to simulate its response. The results show that the triangular groove structure increases the jet angle and effectively compensates for the hydrodynamic force. The steady-state differential… More > Graphic Abstract

Fuyin Ni^1,2, Kai Li^2,*

Energy Engineering, Vol.120, No.5, pp. 1203-1221, 2023, DOI:10.32604/ee.2023.025796

Abstract Unified power quality conditioner (UPQC) with energy storage is commonly based on conventional capacity configuration strategy with power angle control. It has problems such as phase jumping before and after compensation. DC-link cannot continuously emit active power externally. Therefore, this paper presents the compensation strategy of full load voltage magnitude and phase in capacity configuration of UPQC. The topology of UPQC is integrated a series active power filter (SAPF), a shunt active power filter (PAPF) and a photovoltaic-battery energy storage system (PV-BESS). The principle of full load voltage compensation is analyzed based on the PV-BESS-UPQC topology. The magnitude constant of… More > Graphic Abstract

Wei Zhang¹, Mulian Zheng^1,*, Yifeng Li², Wuxi Zheng³

Journal of Renewable Materials, Vol.11, No.5, pp. 2513-2529, 2023, DOI:10.32604/jrm.2023.025275

Abstract Steel slag is characterized by high strength, good wear resistance and micro-expansion. This study aims at exploring the potential of steel slag in cement stabilized aggregates, mainly including mechanical properties, shrinkage and compensation mechanisms. For this purpose, the compressive strength and compressive resilient modulus of cement stabilized aggregates with different steel slag contents (CSMS) were initially investigated. Subsequently, the effects of steel slag and cement on dry shrinkage, temperature shrinkage, and total shrinkage were analyzed through a series of shrinkage test designs. Additionally, in combination with X-ray diffraction (XRD) and Scanning electron microscope (SEM), the characteristic peaks and microscopic images… More >

Yingying Li¹, Hang Jiang¹, Lianjie Yu¹, Jianfeng Li^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.3, pp. 2123-2136, 2023, DOI:10.32604/cmes.2022.021407

Abstract To improve the estimation accuracy, a novel time delay estimation (TDE) method based on the closed-form offset compensation is proposed. Firstly, we use the generalized cross-correlation with phase transform (GCC-PHAT) method to obtain the initial TDE. Secondly, a signal model using normalized cross spectrum is established, and the noise subspace is extracted by eigenvalue decomposition (EVD) of covariance matrix. Using the orthogonal relation between the steering vector and the noise subspace, the first-order Taylor expansion is carried out on the steering vector reconstructed by the initial TDE. Finally, the offsets are compensated via simple least squares (LS). Compared to other… More >

Zhiguo Wang^*, Fangqing Gao, Fei Liu

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.1, pp. 343-355, 2023, DOI:10.32604/cmes.2022.020569

Abstract In this paper, an improved high-order model-free adaptive iterative control (IHOMFAILC) method for a class of nonlinear discrete-time systems is proposed based on the compact format dynamic linearization method. This method adds the differential of tracking error in the criteria function to compensate for the effect of the random disturbance. Meanwhile, a high-order estimation algorithm is used to estimate the value of pseudo partial derivative (PPD), that is, the current value of PPD is updated by that of previous iterations. Thus the rapid convergence of the maximum tracking error is not limited by the initial value of PPD. The convergence… More >

Jianfeng Yang^*, Rende Qi^*, Yang Liu, Yu Ding

Energy Engineering, Vol.119, No.2, pp. 609-620, 2022, DOI:10.32604/ee.2022.016969

Abstract In order to minimize the harmonic distortion rate of the current at the common coupling point, this paper proposes a coordinated allocation strategy of harmonic compensation capacity considering the performance of active power filters (APF). On the premise of proportional distribution of harmonic compensation capacity, the harmonic compensation rate of each APF is considered, and the harmonic current value of each APF to be compensated is obtained. At the same time, the communication topology is introduced. Each APF takes into account the compensation ability of other APFs. Finally, three APFs with different capacity and performance are configured at the harmonic… More >

Kuei-Feng Chang¹, Wen-Goang Yang², Ya-Wen Cheng³, I-Tung Shih^2,*

International Journal of Mental Health Promotion, Vol.24, No.2, pp. 219-236, 2022, DOI:10.32604/ijmhp.2022.018187

Abstract This study explored the mechanism on how volunteers as rationalists use rationalism during their cognitive appraisal process when dealing with emotional events in their social helping behavior such as international rescue events. The authors used the triangulation method to include three studies (Study 1 is a qualitative research which explored ways of TCF leader’s inspiring their volunteer workers; Study 2 is a quantitative research on the decision-making process of volunteer individuals involving in international rescue activities; Study 3 is a quantitative research on individuals’ motivation for joining social helping behavior) for validation of Tzu Chi Foundation (TCF), which is a… More >

Waleed Rafique¹, Ayesha Khan², Ahmad Almogren³, Jehangir Arshad¹, Adnan Yousaf⁴, Mujtaba Hussain Jaffery¹, Ateeq Ur Rehman⁵, Muhammad Shafiq^6,*

CMC-Computers, Materials & Continua, Vol.71, No.3, pp. 4275-4293, 2022, DOI:10.32604/cmc.2022.023588

Abstract An excessive use of non-linear devices in industry results in current harmonics that degrades the power quality with an unfavorable effect on power system performance. In this research, a novel control technique-based Hybrid-Active Power-Filter (HAPF) is implemented for reactive power compensation and harmonic current component for balanced load by improving the Power-Factor (PF) and Total–Hormonic Distortion (THD) and the performance of a system. This work proposed a soft-computing technique based on Particle Swarm-Optimization (PSO) and Adaptive Fuzzy technique to avoid the phase delays caused by conventional control methods. Moreover, the control algorithms are implemented for an instantaneous reactive and active… More >

N. Kanagaraj^*

Computer Systems Science and Engineering, Vol.40, No.2, pp. 517-538, 2022, DOI:10.32604/csse.2022.019149

Abstract In this paper, the hybrid photovoltaic-thermoelectric generator (PV-TEG) combined dynamic voltage restorer (DVR) system is proposed for the power quality disturbances compensation in a single-phase distribution system. The stable and precise level of input voltage is essential for the smooth and trouble-free operation of the electrically sensitive loads which are connected at the utility side to avoid system malfunctions. In this context, the hybrid PV-TEG energy module combined DVR system is proposed in this paper. With the support of the hybrid energy module, the DVR will perform the power quality disturbances compensation effectively with needed voltage and /or power. In… More >