Jiarui Zhang¹, Dan Liu^2,*, Kan Cao², Ping Xiong², Xiaotong Ji³, Yanze Xu¹, Yunfei Mu¹

Energy Engineering, Vol.121, No.8, pp. 2065-2083, 2024, DOI:10.32604/ee.2024.050342

Abstract The system performance of grid-connected photovoltaic (PV) has a serious impact on the grid stability. To improve the control performance and shorten the convergence time, a predefined-time controller based on backstepping technology and dynamic surface control is formulated for the inverter in the grid-connected photovoltaic. The time-varying tuning functions are introduced into state-tracking errors to realize the predefined-time control effect. To address the “computational explosion problem” in the design process of backstepping control, dynamic surface control is adopted to avoid the analytical calculations of virtual control. The disturbances of the PV system are estimated and More >

Tiezhou Wu, Yukan Zhang^*

Energy Engineering, Vol.121, No.8, pp. 2231-2255, 2024, DOI:10.32604/ee.2024.049883

Abstract In order to solve the problem of inconsistent energy in the charging and discharging cycles of lithium-ion battery packs, a new multilayer equilibrium topology is designed in this paper. The structure adopts a hierarchical structure design, which includes intra-group equilibrium, primary inter-group equilibrium and secondary inter-group equilibrium. This structure greatly increases the number of equilibrium paths for lithium-ion batteries, thus shortening the time required for equilibrium, and improving the overall efficiency. In terms of control strategy, fuzzy logic control (FLC) is chosen to control the size of the equilibrium current during the equilibrium process. We… More >

Shan Liu¹, Chengbin Chi¹, Fengze Han², Yanan Wu¹, Lin Zhu¹, Tuo Wang^2,*

Energy Engineering, Vol.121, No.8, pp. 2257-2273, 2024, DOI:10.32604/ee.2024.049861

Abstract Voltage source converter based high voltage direct current (VSC-HVDC) can participate in voltage regulation by flexible control to help maintain the voltage stability of the power grid. In order to quantitatively evaluate its influence on the voltage interaction between VSC-HVDC and line commutated converter based high voltage direct current (LCC-HVDC), this paper proposes a hybrid multi-infeed interaction factor (HMIIF) calculation method considering the voltage regulation control characteristics of VSC-HVDC. Firstly, for a hybrid multi-infeed high voltage direct current system, an additional equivalent operating admittance matrix is constructed to characterize HVDC equipment characteristics under small disturbance.… More >

He Li¹, Xianchao Liu^2,*, Jidong Li¹, Yuchen Qiu²

Energy Engineering, Vol.121, No.8, pp. 2293-2311, 2024, DOI:10.32604/ee.2024.048752

Abstract When employing stepwise inertial control (SIC), wind power generation can offer significant frequency support to the power system, concurrently mitigating energy shortages and suppressing secondary frequency drop. Nonetheless, further investigation is imperative for implementing stepped inertia control due to variations in frequency regulation capabilities and operational safety among diverse wind farm groups. Consequently, this paper advocates a multi-wind farm ladder timing SIC method designed to alleviate secondary drops in system frequency. Initially, the paper introduces the fundamental principles of stepped inertia control for a doubly-fed induction generator (DFIG) and deduces the relationship between support energy,… More >

Lirong Yin¹, Lei Wang¹, Siyu Lu^2,*, Ruiyang Wang², Haitao Ren², Ahmed AlSanad³, Salman A. AlQahtani³, Zhengtong Yin⁴, Xiaolu Li⁵, Wenfeng Zheng^3,*

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.3, pp. 2315-2347, 2024, DOI:10.32604/cmes.2024.050853

Abstract At present, super-resolution algorithms are employed to tackle the challenge of low image resolution, but it is difficult to extract differentiated feature details based on various inputs, resulting in poor generalization ability. Given this situation, this study first analyzes the features of some feature extraction modules of the current super-resolution algorithm and then proposes an adaptive feature fusion block (AFB) for feature extraction. This module mainly comprises dynamic convolution, attention mechanism, and pixel-based gating mechanism. Combined with dynamic convolution with scale information, the network can extract more differentiated feature information. The introduction of a channel More >

Manal El-Hamamsy^*, Hesham Elwakil^†, Amr S. Saad^†, May A. Shawki^*

Oncology Research, Vol.24, No.6, pp. 521-528, 2016, DOI:10.3727/096504016X14719078133528

Abstract Statins have been reported to have a potential radiosensitizing effect that has not been evaluated in clinical trials. The aim of this study was to evaluate the efficacy and safety of simvastatin in addition to whole-brain radiation therapy (WBRT) in patients with brain metastases (BM). A prospective randomized, controlled, open-label pilot study was conducted on 50 Egyptian patients with BM who were randomly assigned to receive 30-Gy WBRT (control group: 25 patients) or 30 Gy WBRT+ simvastatin 80 mg/day for the WBRT period (simvastatin group: 25 patients). The primary outcome was radiological response at 4… More >

Guanling Chen¹, Zhaoze Guo¹, Minfeng Liu, Guangyu Yao, Jianyu Dong, Jingyun Guo, Changsheng Ye

Oncology Research, Vol.25, No.9, pp. 1567-1578, 2017, DOI:10.3727/096504017X14897173032733

Abstract Capecitabine has consistently demonstrated high efficacy and acceptable tolerability in salvage chemotherapy for advanced breast cancer. However, there remains no consensus on its role in adjuvant chemotherapy for early breast cancer (EBC). To estimate the value of capecitabine-based combination adjuvant treatment in EBC, eight randomized controlled trials with 14,072 participants were analyzed. The efficacy and safety outcomes included disease-free survival (DFS), overall survival (OS), relapse, breast cancer-specific survival (BCSS), and grades 3–5 adverse events. Capecitabine-based combination adjuvant chemotherapy demonstrated a 16% increase in BCSS (HR = 0.84, 95% CI = 0.71–0.98, p = 0.03) in the… More >

Alexis Salazar-Navarro¹, Victor Ruiz-Valdiviezo², Jose Joya-Dávila³, Daniel Gonzalez-Mendoza^1,*

Phyton-International Journal of Experimental Botany, Vol.93, No.5, pp. 923-949, 2024, DOI:10.32604/phyton.2024.049612

Abstract Coffee Leaf Rust (CLR) is caused by Hemileia vastatrix in Coffea spp. It is one of the most dangerous phytopathogens for coffee plantations in terms of coffee productivity and coffee cup quality. In this review, we resume the problem of CLR in Mexico and the pathogenesis of H. vastatrix. The review abord plant-pathogen interactions which lead a compatible or incompatible interactions and result in CLR disease or resistance, respectively. The review abord Coffea spp. defense response pathways involved in H. vastatrix pathogenicity. Additionally, current measures to control H. vastatrix proliferation and germination were aborded focused on phytosanitary actions, and biological More >

Yuping Bian^*, Xiu Wan, Xiaoyu Zhou

Energy Engineering, Vol.121, No.6, pp. 1637-1656, 2024, DOI:10.32604/ee.2024.047678

Abstract To address uncertainty as well as transient stability constraints simultaneously in the preventive control of wind farm systems, a novel three-stage optimization strategy is established in this paper. In the first stage, the probabilistic multi-objective particle swarm optimization based on the point estimate method is employed to cope with the stochastic factors. The transient security region of the system is accurately ensured by the interior point method in the second stage. Finally, the verification of the final optimal objectives and satisfied constraints are enforced in the last stage. Furthermore, the proposed strategy is a general More >

Yuanjun Dai, Haonan Li, Baohua Li^*

Energy Engineering, Vol.121, No.6, pp. 1607-1636, 2024, DOI:10.32604/ee.2024.047255

Abstract This paper addresses the micro wind-hydrogen coupled system, aiming to improve the power tracking capability of micro wind farms, the regulation capability of hydrogen storage systems, and to mitigate the volatility of wind power generation. A predictive control strategy for the micro wind-hydrogen coupled system is proposed based on the ultra-short-term wind power prediction, the hydrogen storage state division interval, and the daily scheduled output of wind power generation. The control strategy maximizes the power tracking capability, the regulation capability of the hydrogen storage system, and the fluctuation of the joint output of the wind-hydrogen… More >