Yun Zhang^1,*, Zifen Han², Biao Tian¹, Ning Chen², Yi Fan³

Energy Engineering, Vol.122, No.1, pp. 167-184, 2025, DOI:10.32604/ee.2024.056190 - 27 December 2024

Abstract The new energy power generation is becoming increasingly important in the power system. Such as photovoltaic power generation has become a research hotspot, however, due to the characteristics of light radiation changes, photovoltaic power generation is unstable and random, resulting in a low utilization rate and directly affecting the stability of the power grid. To solve this problem, this paper proposes a coordinated control strategy for a new energy power generation system with a hybrid energy storage unit based on the lithium iron phosphate-supercapacitor hybrid energy storage unit. Firstly, the variational mode decomposition algorithm is… More >

Yonghang Sun^1,2, Anyu Xu², Heow Pueh Lee², Hui Zheng^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.31, No.2, pp. 1-1, 2024, DOI:10.32604/icces.2024.010895

Abstract Metamaterials with inertial amplification components exhibit unique bandgap behaviors which can be utilized on the vibration suppression of mechanical structures. In this study, novel cantilever-type inertial amplification mechanisms are periodically attached to the stiffened composite plate to realize the low-frequency bandgaps and vibration suppression. This type of metamaterial mitigates the vibration by amplifying the inertia of the added small mass, which has great application potential in many industrial scenes. For the sake of the efficient calculations, a semi-analytical method based on the energy generalized variational principle is promoted, which can predict the bandgap behaviors and… More >

Weiru Wang¹, Yulong Cao^1,*, Yanxu Wang¹, Jiale You¹, Guangnan Zhang¹, Yu Xiao²

Energy Engineering, Vol.121, No.12, pp. 3801-3823, 2024, DOI:10.32604/ee.2024.055398 - 22 November 2024

Abstract To ensure frequency stability in power systems with high wind penetration, the doubly-fed induction generator (DFIG) is often used with the frequency fast response control (FFRC) to participate in frequency response. However, a certain output power suppression amount (OPSA) is generated during frequency support, resulting in the frequency modulation (FM) capability of DFIG not being fully utilised, and the system’s unbalanced power will be increased during speed recovery, resulting in a second frequency drop (SFD) in the system. Firstly, the frequency response characteristics of the power system with DFIG containing FFRC are analysed. Then, based… More >

Haitao Liu^1,2,*, Jiaming Wang¹, Xiuliang Zhang¹, Yanji Jiang², Qian Xiao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 2747-2772, 2024, DOI:10.32604/cmes.2024.047129 - 11 March 2024

Abstract The expansion chamber serves as the primary silencing structure within the exhaust pipeline. However, it can also act as a sound-emitting structure when subjected to airflow. This article presents a hybrid method for numerically simulating and analyzing the unsteady flow and aerodynamic noise in an expansion chamber under the influence of airflow. A fluid simulation model is established, utilizing the Large Eddy Simulation (LES) method to calculate the unsteady flow within the expansion chamber. The simulation results effectively capture the development and changes of the unsteady flow and vorticity inside the cavity, exhibiting a high… More > Graphic Abstract

Crystal Lihong Yan¹, Ryan A. Gallo², Madhavi Pandiri³, Stephen J. Gallo⁴

Canadian Journal of Urology, Vol.30, No.2, pp. 11505-11508, 2023

Abstract Condyloma acuminatum with synchronous squamous cell carcinoma in situ (CIS) rarely occurs in the bladder. In developed countries, bladder squamous cell carcinoma (SCC) is uncommon. Among the various noninvasive squamous bladder lesions, there is significant morphological overlap, which further complicates accurate diagnosis. Immunosuppression and human papilloma virus increase the risk of bladder condyloma acuminatum, which has a strong association with bladder SCC. Herein, we describe a case of a 79-year-old man with a history of end-stage renal disease with kidney transplantation and anal SCC who presented with bladder squamous cell CIS arising in the background More >

LIPING YE^1,2,3,#, HUIYAN SUN^4,#, XINHUA LIANG^2,#, WENXU PAN², LI XIANG^2,3, WENJUN DU², LANLAN GENG², WANFU XU^2,3,*, SITANG GONG^1,2,3,*

BIOCELL, Vol.47, No.12, pp. 2709-2719, 2023, DOI:10.32604/biocell.2023.044295 - 27 December 2023

Abstract Introduction: Helicobacter pylori is a risk factor for the development of peptic ulcers with autophagy dysfunction. Omeprazole was widely known as the first-line regimen for H. pylori-associated gastritis. Objectives: The objective of this work was to assess the role of omeprazole on cell pyroptosis and autophagy. Methods: The clinical samples were collected. Quantitative polymerase chain reaction, western blotting, enzyme linked immunosorbent assay, and immunofluorescence (IF) analysis were conducted to reveal the mechanism of omeprazole on cell pyroptosis and autophagy. Results: The results revealed that omeprazole could decrease cell pyroptosis, which was attributed to the downregulation of cleaved caspase-1 expression,… More >

Kanhua Su, Jian Wei^*, Meng Li, Hao Li, Wenghao Da, Lang Zhang

Sound & Vibration, Vol.57, pp. 97-117, 2023, DOI:10.32604/sv.2023.043734 - 14 December 2023

Abstract During the drilling process, stick-slip vibration of the drill string is mainly caused by the nonlinear friction generated by the contact between the drill bit and the rock. To eliminate the fatigue wear of downhole drilling tools caused by stick-slip vibrations, the Fractional-Order Proportional-Integral-Derivative (FOPID) controller is used to suppress stick-slip vibrations in the drill string. Although the FOPID controller can effectively suppress the drill string stick-slip vibration, its structure is flexible and parameter setting is complicated, so it needs to use the corresponding machine learning algorithm for parameter optimization. Based on the principle of… More > Graphic Abstract

Chongyang Zhao, Wei Chai, Beibei Rui, Lin Chen^*

Energy Engineering, Vol.120, No.11, pp. 2683-2705, 2023, DOI:10.32604/ee.2023.029620 - 31 October 2023

Abstract At present, the direct drive permanent magnet synchronous generator (DD-PMSG) grid connected system based on virtual synchronous generator (VSG) control will experience power oscillation at sub synchronous frequencies. The mechanism and characteristics of this new type of sub-synchronous interaction (SSI) are not yet clear, and the system cannot recover to steady state solely based on the characteristics of VSG itself. Especially when connected to a weak current network, oscillations are more pronounced, affecting the stability of the system. In severe cases, the system may trigger shutdown protection and be disconnected from the network. Existing research More >

JIAN LI¹, QINGQING WANG², XIAOYING ZHANG^1,*

BIOCELL, Vol.47, No.6, pp. 1307-1316, 2023, DOI:10.32604/biocell.2023.028714 - 19 May 2023

Abstract Scutellarin (SCU) is a herbal flavonoid glucuronide with multiple pharmacological activities, including anti-oxidant, anti-inflammation, vascular relaxation, anti-platelet, and myocardial protection. However, the effect of SCU on complete Freund’s adjuvant (CFA)-induced rheumatoid arthritis (RA) had not been studied. In this study, we investigated the beneficial effects of SCU in the CFA-induced RA mice model and the anti-arthritic activity was evaluated by paw edema. Enzyme-linked immunosorbent assay (ELISA) was carried out to evaluate the plasma levels of immunoglobulin (Ig)G, IgE, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, receptor activator of nuclear factor-κB ligand (RANKL), and osteoprotegerin (OPG).… More >

Hui Fang¹, Jingsen Zhou¹, Haozheng Wang^2,*, Yanxu Wang², Hongji Xiang¹, Yechun Xin²

Energy Engineering, Vol.120, No.4, pp. 831-850, 2023, DOI:10.32604/ee.2023.025171 - 13 February 2023

Abstract Recently, high-frequency oscillation of the modular multilevel converter (MMC) based high-voltage direct current (HVDC) projects has attracted great attentions. In order to analyze the small-signal stability, this paper uses the harmonic state-space (HSS) method to establish a detailed frequency domain impedance model of the AC-side of the HVDC transmission system, which considers the internal dynamic characteristics. In addition, the suggested model is also used to assess the system's high-frequency oscillation mechanism, and the effects of the MMC current inner loop control, feedforward voltage links, and control delay on the high-frequency impedance characteristics and the effect More >