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The irradiation variations caused by cloud changes can cause rapid power fluctuations in large photovoltaic (PV) plants. The increased PV power share of the grid adversely affects the quality of power and the reliability of the power supply. Energy storage systems (ESSs)are often used to mitigate power fluctuations in the grid through various control algorithms. These algorithms create an ESS power reference that opposes the variations of the PV and reduces them to an acceptable value. Despite their everyday use, there have been few performance comparisons among the various methods, especially battery status, and the battery can operate in several systems with various smoothing methods. The paper aims to analyze the ramp-rate and step-rate control methods for smoothing solar PV fluctuations based on the irradiation profiles in a DC microgrid (MG) environment. The battery in the system operates as a continuous energy application, and a supercapacitor (SC) is used to remove transients in the battery system. The combined battery-SC coordinated system improves the performance of the DC microgrid system. The battery cycle analysis and depth are conducted using the well-established Coulomb counting technique. MATLAB/Simulink validates the simulation results, and the OP-5700 HIL test bench conducts real-time results.

Dishonest academic behavior (DAB) by students in Chinese higher education institutions has become a significant concern. However, the related study of academic dishonesty in mainland China is very limited. This study fills this gap by examining the theory of planned behavior and its three extended versions, validating the effectiveness of predicting DAB among Chinese undergraduates, and testing 11 developed hypotheses. This study uses a quantitative research design, and responses are collected online from 525 undergraduate students from five disciplines in the second to fourth year at a public university in China. The results reveal the proposed models have good fitting indices and support 10 hypothetical relationships. These relationships demonstrate that attitudes, norms and control beliefs significantly impact intentions and justifications. Meanwhile, behavioral control, intentions, and justifications significantly influence DAB. Notably, this study found a direct and significant effect of MO on justifications. Therein, Model four best explains the variance in DAB and provides practical support for the expanded TPB models’ application in China.

The steady rise in utility grid penetration of single phase solar photovoltaic system has contributed to the mandatory requirement of Low Voltage Ridethrough (LVRT) capability. LVRT capability provides stable grid integration during transient conditions. A seamless LVRT capability operation in a single phase photovoltaic system using peak value based fault detection and Orthogonal Signal Generation (OSG) based voltage sag detection is conducted. In this paper, two controllers are employed for two different operations. The PQ theory controller is used for power control operation and Proportional–Resonant (PR) with Harmonic Compensation (HC) controller is used for current control operation in LVRT. MATLAB/Simulink verifies the LVRT operation mode as per the grid code requirements to ride through voltage sag during fault condition. It is observed that the system is in operation during transient conditions and provides reactive support to ride through the fault.

This paper consolidates the findings of two studies conducted in Brunei Darussalam on the incidences of bullying among Primary and Secondary school pupils. Students from both Primary and Secondary schools responded to a questionnaire on the incidence of bullying in their school. Results from the studies show that the frequency of the incident of bullying peaked at around secondary one and showed a decline in the upper forms. While the ranking of the types of bullying experienced by students at the different levels of schooling were similar, differences were noted in the ranking of the types of bullying experienced by boys and girls particularly in the primary years. Psychological bullying was more common among girls whereas bullying of a physical nature was more common among boys. The classroom was the place where students‟ experienced most bullying and a close friend and parent were the individuals to whom most students would report the incidence of bullying. Some implications for classroom practice and further research are discussed.

In this paper presents a comparative analysis of two control method applied to a single phase Shunt Active Power Filter (SAPF). It is about Model Predictive Control (MPC) based Direct Current Control (DCC) and Indirect Current Control (IDCC) strategy. The performances of two current control strategies were verified through a simulation with MATLABSimulink Software. Simulation results confirmed that compared to the DCC strategy, the IDCC strategy using MPC becomes simpler and need less hardware components.

Green-synthesized silver and copper nanoparticles (NPs), along with their composites, exhibit various biological activities. Ocimum sanctum (Holy basil), traditionally used as medicine in South Asia, treats respiratory disorders, digestive issues, skin diseases and inflammatory conditions. Modern scientific studies support these bioactivities; however, no studies have investigated their bioactivity in combination with NPs. In this study, silver and copper NPs were synthesized using AgNO3 and CuSO4·5H2O solutions, respectively, with Ocimum sanctum leaf extract, and their antibacterial, antioxidant and anticancer properties were examined. Spectroscopic analyses, including Fourier transform infra-red (FTIR), transmission electron microscopy (TEM) and X-ray diffraction (XRD), elucidated the physicochemical characteristics of the green-synthesized nanoparticles (Os-AgNPs and Os-CuNPs), revealing sizes of 11.7 and 13.1 nm, respectively. The Os-AgNPs:Os-CuNPs nano-composite with a 1:2 ratio exhibited a zone of inhibition ranging from 8 to 12 mm against tested bacterial pathogens. Additionally, the NPs and their composites demonstrated potent antioxidant activity, with notable 2-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity observed in composites with ratios of 2:1 and 1:2. Furthermore, they displayed potential anticancer activity against human leukaemia (Jurkat) cancer cells. Although no distinct difference in anticancer property was observed among the NPs and their composites, our study highlights their well-defined nanostructure and significant biological activity, suggesting their potential as therapeutic agents in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

This paper demonstrates an enhancement of power quality for a photovoltaic (PV) system connected to the grid with a hybrid energy storage system (HESS). The proposed system utilizes a ramp-rate control (RRC) strategy to limit severe fluctuations in the PV power output. Battery storage is integrated to store surplus energy generated by the PV system and is used for continuous power application. A high-power density device, known as a supercapacitor (SC), is employed to mitigate transient fluctuations in the battery. The proposed system facilitates smooth PV power generation, stabilizes the DC bus voltage (VDC), and eliminates source current harmonics induced by non-linear loads. The Shunt Active Power Filter (SAPF) discussed in this paper serves two primary purposes. Firstly, it acts as a reactive power buffer, smoothing out fluctuations and reducing current harmonic distortions. Secondly, it enables active power injection into the grid, utilizing a specific renewable solar PV source. The efficiency of the modeled compensation system is demonstrated by the sinusoidal shape of the current and the compensation of reactive power (RPC). The targeted system showcases the effectiveness of the current setup by exhibiting low total harmonic distortion (THD). The multifunctional features of the proposed system were implemented using the MATLAB/Simulink software, and the results were validated using an OP5700 Hardware-in-the-Loop (HIL) test bench. This integration of distributed power generation capabilities not only enhances the overall power quality but also improves the efficient utilization of renewable energy resources (RESs). [ABSTRACT FROM AUTHOR]