Power Source Research Articles

A Critical Discourse Analysis of Feminine and Masculine Identity in August Wilson’s Pittsburg Cycle

In his collection of ten plays, The Pittsburg Cycle, August Wilson (1945-2005) presents the social dynamism of African Americans across the twentieth century America. In his plays, many newly freed African slaves move to the North, hoping to shape their identity as respectable citizens of great worth. They are, however, reckoned as foreigners in a new habitus. Since they have lost contact with their past heritage and have no access to their social codes as a source of power, they search for means through which they can concretize the song they carry within themselves as a sign of their true African heritage. Through the theory of critical discourse analysis, this article focuses on Michel Foucault’s theory of discourse to study, analyze, and compare the discourse of both male and female characters of the plays. According to the age-old western tradition, male discourse represents power, assurance, and certainty in contrast to female discourse imbued with characteristics opposite to the mentioned ones. This article aims to explore how Wilson subverts the male and female discourse to create a nongendered African soul, who embodies characteristics of both sexes.

A Hybrid Parameters Estimation Approach for Power Consumption Modeling of Ground Mobile Robots With Unknown Payload

ABSTRACTTypically, batteries are the main power source for mobile robots, and the practical constraints in carrying them pose challenges in achieving efficiency, autonomy, and safety objectives in robotic missions. Moreover, dealing with battery degradation requires a precise understanding of energy consumers' behavior in the system. Therefore, establishing an energy consumption model has an important role in addressing these challenges. This study focuses on the modeling and estimation of power consumption in indoor ground mobile robots with unknown payloads. We investigate key components and parameters that influence the actuation energy consumption of ground mobile robots equipped with DC motors, particularly in the context of pure rolling without slipping. To estimate the actuation power consumption of ground mobile robots, we present a hybrid parameters estimation approach. This method includes an offline step for estimating the mass‐decoupled coefficients of a power model, followed by two online steps for estimating the robot's unknown payload and its actuation power consumption. Simulation and experimental results with a differential drive robot (Turtlebot3) validate the effectiveness of the proposed approach. Additionally, the performance of the proposed power consumption estimation method is compared with two other data‐driven models based on multivariate linear regression and multilayer perceptron neural networks. The results demonstrate that the proposed method provides improved power consumption estimation accuracy on the selected indicators compared to the others. We also emphasize the importance of balancing the accuracy of power consumption estimation with its associated costs in the context of the proposed approach. This extra cost includes the energy needed for additional data measurement and processing. Considering this trade‐off is crucial for the practical implementation and resource optimization in robotic systems.

A novel horizontal self-tuning piezoelectric energy harvester based on a beam-slider system

Abstract With the rapid development of piezoelectric energy harvesting technologies, this approach is emerging as a promising power source for smart sensors. Despite this progress, a significant challenge remains in achieving a wider bandwidth while increasing the output power. In response to this challenge, this paper introduces a horizontal self-tuning beam-slider piezoelectric energy harvester (STBS-PEH). This innovative harvester employs a unilateral beam-slider mechanism to enable self-tuning of the energy harvesting by adjusting its resonant frequency to match the external excitation frequency. The electromechanical coupled dynamic model of this harvester has been established. Comprehensive simulations and experimental analysis have been conducted to demonstrate the wide bandwidth and high output power characteristics of the proposed harvester. Notably, the simulation results exhibit strong agreement with the experimental findings. The resonance response bandwidth of the STBS-PEH is particularly noteworthy, which is twice that of a conventional cantilever beam piezoelectric energy harvester. The root mean square (RMS) voltage and output power of the developed STBS-PEH can reach 23.54 V and 194.61 µW, respectively, at a frequency of 21 Hz, with an excitation amplitude of 0.5 g. These results demonstrate that the STBS-PEH is capable of powering low-power electronic devices in a broadband vibrational environment.

Economic optimization scheduling of microgrid group based on chaotic mapping optimization BOA algorithm

Due to the intermittency and volatility of distributed power sources, the microgrid system has poor stability and high operation cost. Therefore, the study proposes an economic optimization scheduling strategy based on the chaotic mapping butterfly optimization algorithm and the mathematical model of microgrid group system. The study creates simulation trials of function poles and microgrid group operation to confirm the strategy’s efficacy. According to the experimental findings, the multimodal function of the enhanced butterfly optimization method had a variance of 0.0000E + 00, and the function’s optimal value was less than 10–30, and the calculation time is 4.5s. The variance on the fixed dimensional function was 0.0000E + 00 and the optimal value of the function was 10 − 3.5,and the calculation time is 4.7s. The algorithmic curve all digging depth was maximum and convergence speed was fastest. The microgrid group system had the lowest economic cost of 4029.32 yuan in the grid-connected mode and 3343.39 yuan in the off-grid mode. The study proves that the energy coordination and economic management of this strategy are greatly optimized, which can effectively protect the energy storage equipment and guarantee the smooth power consumption of the system. This provides an innovative theoretical basis for optimization scheduling of microgrid group.

Characterization of tin oxide nanoparticles synthesized by discharging the non-thermal plasma jet in liquid and their application as an antibacterial agent

This study reports the synthesis of tin oxide nanoparticles using a non-thermal plasma jet technique. Spectroscopic analysis (OES) of plasma was carried out at atmospheric pressure to measure the plasma parameters used in the synthesis of nanoparticles. SnO2 NPs were synthesized at different durations (3 and 5 min) using a DC-high-voltage power source with a voltage of 13 kV.X-ray diffraction (XRD) showed that SnO2 NPs, prepared in 3 min, are rutile tetragonal polycrystalline and have an average crystallite size of 12.45 nm. Field emission scanning electron (FE-SEM) images also show that the nanoparticles are spherical and homogenous, with an average nanostructure diameter of 22 to 58 nm for both (3 and 5 min) preparation times. UV–Vis spectroscopy showed peaks of surface plasmon resonance around 255–260 nm. The ICP-mass technique was used to evaluate nanoparticle concentrations, which were between 90–100 μg/ml. Zeta potential (ZP) measurements revealed that the particles are relatively stable colloids. The study shows that synthesized nanoparticles have exceptional antibacterial efficacy against Escherichia coli and Staphylococcus aureus bacteria. These nanoparticles are low-cost, scalable, and can be synthesized using gas or liquid phases, enabling the synthesis of a wide range of nanoparticles suitable for various pathogenic bacterial types.

Investigation of a fast gate driver based on a half-turn planar transformer.

This paper presents a magnetically isolated gate driver for the fast switching of IGBT (Insulated Gate Bipolar Transistor) in compact pulsed power sources with sharp rising edges and flat-top pulses for the application of electromagnetic launch and food processing. The proposed gate driver is implemented based on a planar transformer with a half-turn winding arrangement to increase the amplitude of the driving voltage pulse. With the half-turn winding arrangement, the leakage inductance of transformers decreases by 31.1% compared to the interleaving structure. This decrease enables a fast rise time of the driving voltage pulse. Furthermore, the gate drivers are used to drive the IGBT switching a Blumlein pulse forming network. The results show that the di/dt of the applied commercially available Si IGBT is about 10.10 A/ns with a gate voltage of 50V and a gate capacitance charging time of about 88ns, proving the effectiveness of the gate driver and providing a high-performance driving scheme for the fast switching of Si IGBT.

Multiscale formation mechanism and instability characteristic of the submerged vortices caused by a closed pump intake

The intake system serves as a crucial inlet structure for tidal pumping stations along the coastal regions. However, the various types of submerged vortices caused by the closed intake disrupt the energy-conversion stability, limiting the efficient and safe operation of the units. Especially when the multiple vortices are mixed enter the pump, the pump's energy consumption increases, and the hydraulic stability of the intake further decreases. This study used the high-precision simulation method to elucidate that the anisotropic turbulent structure around the roof-attached vortex (RAV) and the Reynolds shear stress are the critical factors for initiating small-scale RAV. The vertical and its enstrophy transport equation were used to explain that the vortex stretching term is the primary source of inducing the vertical vorticity evolution of RAV and floor-attached vortex (FAV). The tilting term provides a power source for vortex wandering. Based on the high-speed visualization experiment, the instability characteristics analysis of the vortices showed that the root of RAV dissipation was the existence of a critical stagnation point, SRAV, and the dissipation form exhibited “bubble-like fragmentation.” The unstable dissipation of the FAV does not have a vital stagnation point, and the dissipation form manifests as “vortex filament dissipation.” The results have important academic value and theoretical guidance significance for ensuring the safe and efficient operation of the tidal units.

Titanate nanorod/reduced graphene oxide-filled poly (vinylidene fluoride) fibers as piezoelectric nanogenerators

To investigate the influence of nanorod ceramic powders MTiO3 (M: Mg, Co, Ni) as fillers on the electrical performance, piezoelectric nanogenerators (PENG) device, were constructed using the electrospinning method with polyvinylidene fluoride (PVDF), reduced graphene oxide (RGO), and ceramic powders. The composite nanofibers were characterized using SEM, EDX, ATR-FTIR, EDS-mapping analysis, and XRD. Sensing capacity of the PVDF-RGO-MTiO3 nanofiber-based PENG were compared. Utilizing CoTiO3 (CT) in the PENG resulted in a voltage output of 17.03, which exhibited the best piezoelectric response. Observations revealed that mechanical stimulation could charge different capacitors, suggesting a viable platform for removing the requirement of an external power source for operating portable devices. With varying resistances in the circuit, the resistance of 104 Ω produced the maximum power density of 1.40 mW/cm2. When comparing the P-RGO-CT composite to pure PVDF, the differential scanning calorimetric analysis revealed that the thermal stability and crystallinity percentage increased. Tensile testing was used to evaluate the mechanical characteristics of P-RGO-CT PENG. The maximum stress and breaking strain that the nanofiber film can tolerate are 50 kPa and 33.9%, respectively. EIS investigations obtained that the real intrinsic internal resistance of the P-RGO-CT PENG electrode is lower than PVDF, demonstrating the good conductivity of the synthesized PENG electrode. The impedance spectrum of the PENG electrode is almost parallel to the Zim axis, demonstrating good capacitance performance.

Techno-economic performance of different DC power distribution networks in official buildings based on a real-time analysis method

The integration of photovoltaic (PV) and energy storage systems into official buildings has garnered considerable attention, which are recognized as DC power sources. Notably, DC power can satisfy the majority of electrical demands in official buildings. The primary objective of this research is to enhance overall system efficiency by efficiently utilizing renewable energy through direct current (DC) power distribution compared to alternating current (AC) systems. This study proposes a techno-economic analysis framework to guide designers in selecting system configuration and voltage levels. The analysis covers various PV capacities, load compositions, and battery capacities, with the aim of optimizing power distribution efficiency and achieving a more competitive levelized cost of energy (LCOE). The proposed model integrates the dynamic efficiency of actual converters and wire gauges, enabling real-time computation of the energy supply–demand balance within the power distribution system, including associated conversion and transmission losses. The results indicate that conversion loss accounts for approximately 80% of the overall energy loss within power distribution networks. The implementation of DC power distribution significantly improves system efficiency and economic viability. Specifically, the DC375 system exhibits superior techno-economic performance in scenarios involving high PV and battery capacities. In scenarios with limited PV and battery capacity, the building power distribution system should employ a hybrid AC-DC topology to efficiently distribute the available PV output to building loads powered by DC

Probabilistic modeling and optimization of microgrids with EV parking lots and dispersed generation

Distributed generation sources provide self-governing power during outages, making microgrids and islanded distribution networks vital for service endurance, superior power quality, reliability, and operative efficiency. However, microgrids structure are difficult to control, particularly in islanded mode where no main power source exists if the main grid fails. Fast responses from discrete generation sources using power electronics can undermine the grid during faults or normal operations without proper regulations. The double-fed induction generator (DFIG) has become the preferred wind turbine generator owing to its low cost and flexibility to varying wind speeds. This paper presents a probabilistic scheduling for day-ahead microgrid programming that includes EV parking lots and dispersed generation resources. The microgrid works in both normal and islanded modes depending on main grid conditions. The uncertainty in EV parking lot usage is modeled hourly using the Z-number method, while wind and solar generation, market prices, and loads are modeled using the Monte Carlo method. Scenario-based incidents in the upstream grid that lead to microgrid islanding are considered, focusing on the time and duration of impact. The optimization model accounts for uncertainty, EV charging/discharging, and operational costs under normal and fault conditions. The fault ride-through (FRT) method for maintaining DFIG stability in islanded microgrids are proposed. In this technique stabilizes terminal voltage during faults by employing a resistor in series with the DFIG stator, enhancing voltage stability and FRT capability. Without these methods, the DFIG may lose stability after clearing transient errors, risking generator loss and threatening microgrid stability, particularly in islanded mode. The effectiveness of these control and protection strategies is validated through comprehensive simulations in MATLAB.

Model for investigating cathode dual-population microfluidic microbial fuel cells

Microfluidic microbial fuel cells (MMFC) are one of the most promising power sources. However, due to the lack of clarity in the internal operating mechanism, the output performance is suboptimal. Thus, a comprehensive two-dimensional cathode dual-population model is developed to gain deeper insights into internal workings. Based on verifying the accuracy of the model, the influence of temperature, ionic strength, and spacing of electrode on the performance and microbial growth of MMFC are explored. The finding reveal a nonlinear trend in the performance of MMFC at temperatures of 293.15 K and 313.15 K. Furthermore, the impact of electrode spacing and ionic strength on the performance of MMFC is examined, thereby emphasizing the applicability in experimental research and numerical simulation. This study provided insights into the operating mechanism of dual-population microbial microfluidic fuel cells.

Fault diagnosis of cells in PEM electrolyzer stack under fluctuating power source

The scale of hydrogen production using renewable energy is expanding with the global energy transition accelerating. Safety in hydrogen production is gaining increased attention. Compared to stable power supplies, the voltage of the electrolyzer stack fluctuates dynamically with input power in the wind and photovoltaic systems. For this reason, a fault diagnosis method for electrolyzers under fluctuating power sources is proposed. Firstly, the faults of the sensor and electrolyzer are distinguished by interleaved voltage detection to avoid the misdiagnosis caused by the sensor failure. Secondly, an improved variable mode decomposition method is introduced to process the raw voltage signals to weaken the influence of inter-cell inconsistency on fault diagnosis. Furthermore, the fault characteristics are highlighted with a shortened fault identification time. Then, the fault characteristics are extracted by the degree of cell voltage fluctuation with the occurrence of faults is judged by the difference in the degree of fluctuation between neighboring electrolyzers. Finally, faults such as short circuits and water shortages in the electrolyzer are diagnosed using the correlation differences in cell voltage between different faults. The feasibility of this fault diagnosis method is validated through case studies and comparative analyses.

Security Requirements Utilizing Power Adjustment from Distributed Power Sources

Security Requirements Utilizing Power Adjustment from Distributed Power Sources

A Review of Energy Harvesting Techniques for Self-Powered IoT Devices

The Internet of Things (IoT) manages a vast network of interconnected smart devices that collect, transmit, and analyze data from their environment using embedded components like processors, sensors, and communication equipment. These devices, which require efficient power sources, often rely on batteries that limit their operational lifespan and increase environmental impact. This paper provides a comprehensive review of energy harvesting techniques aimed at enhancing the longevity and sustainability of IoT devices. The methodology involves a comparative analysis of various energy harvesting sources such as solar, thermal, RF, and mechanical energy focusing on their efficiency, applicability, and integration within wireless sensor networks (WSNs). Key contributions include the identification of current limitations in energy harvesting technologies, such as low energy conversion efficiency and intermittency, and the proposal of solutions to optimize energy capture and storage. The results demonstrate that integrating multiple energy sources can significantly improve power availability and reduce dependence on conventional batteries. This review concludes by outlining the ongoing challenges and future research directions needed to develop efficient, reliable, and cost-effective energy harvesting systems for IoT applications.

Integrating Small Modular Reactors and Policy Frameworks for Sustainable Energy Security in Indonesia

This study evaluates the potential of Small Modular Reactors (SMRs) as a sustainable solution for Indonesia's energy diversification. Amid Indonesia’s rising energy demands and environmental commitments, SMRs-particularly Small Modular Molten Salt Reactors (SM-MSRs)-present an alternative to conventional power sources. SMRs offer advantages like modularity, operational efficiency, and safety, making them suitable for Indonesia’s geographically dispersed landscape. Using a qualitative descriptive approach, this research examines the technical, regulatory, and societal factors influencing SMR integration. Findings reveal that while SMRs show competitive Levelized Cost of Electricity (LCOE) compared to coal, challenges remain, including stringent regulatory requirements, high initial capital costs, and limited public acceptance due to nuclear safety concerns. Policy adjustments, community engagement, and collaboration with established SMR programs globally are suggested to address these issues. Additionally, SMRs’ scalability and compatibility with renewables support Indonesia’s goals for a resilient energy mix, potentially transforming remote energy access. This comprehensive approach underscores the viability of SMRs within Indonesia’s energy transition, contributing to a cleaner, more flexible energy infrastructure

Hybrid energy management strategy based on neural networks robust to fluctuations in operational load

As global regulations on carbon neutrality tighten, the maritime industry, led by the IMO, has set a goal of achieving net-zero emissions by 2050. The electrification of ship propulsion systems is consequently accelerating. Hybrid electric propulsion ships, which combine internal combustion engines with auxiliary power sources, offer a practical solution by improving fuel efficiency and reducing emissions. However, heuristic or pre-trained energy management strategies designed for fixed conditions often struggle under fluctuating loads. This study addresses these limitations by proposing a hybrid energy management strategy that generates probabilistic operational profiles based on representative load data. A neural network controller, trained on nine global control solutions for newly generated operation cycles using Markov chain methods, maintains approximately 37% engine thermal efficiency even under variable loads. A performance validation showed that the proposed strategy resulted in 0.56% higher fuel consumption compared to the global solution, while still supporting implementation with each time step calculation taking approximately 0.072 ms, achieving near real-time performance. This small deviation highlights the trade-off between time-efficient applicability and near-optimal efficiency. By overcoming the limitations of fixed-condition strategies, this research offers a robust and adaptive approach for hybrid propulsion systems, making it suitable for immediate use in eco-friendly ships.

Addendum to: “An algorithm for computing the lithium concentration in Li-ion battery electrode particles with the lithium concentration-stress coupling model” [J. Power Sources. 556 (2023) 232234]

Addendum to: “An algorithm for computing the lithium concentration in Li-ion battery electrode particles with the lithium concentration-stress coupling model” [J. Power Sources. 556 (2023) 232234]

Lightweight energy harvesting backpack achieved with a slingshot-inspired flexible accelerator

The energy harvesting backpack (EHB) has been recognized as a sustainable power source for wearable electronics, but its daily applications have been hindered by the rigid and heavy frame and accelerator structure. Therefore, a flexible and lightweight design strategy for EHBs is proposed based on a slingshot-inspired flexible accelerator (FA). The proposed FA accomplishes the speed acceleration for harvester actuation by rapidly releasing accumulated elastic potential energy. Then, a 1.9 kg electromagnetic EHB with the FA (FA-EEHB) is modeled, tested, and applied to wearable electronics. Actuated by 3.0 Hz ultralow-frequency vibrations, the FA-EEHB with a 2.0 kg payload can generate 215.1 mW output power, which is over eight times the 26.6 mW output of an EHB without FA. With a small payload of 1.0 kg, the FA-EEHB can work well over a large traveling speed range from 4 km/h to 9 km/h. The application experiment of the FA-EEHB was conducted at 5 km/h traveling speed with a 2.0 kg payload to demonstrate the ability to continuously power a lamp, charge a smartphone, and sustain a tracking and positioning system. This study provides a distinctive strategy for the flexible and lightweight design of EHBs with small payloads.

Investigating effects of air-cold plasma jet on enzymatic activity and nutritional quality attributes of Mangosteen (Garcinia mangostana L.) juice

This study aimed to investigate the effects of air-cold plasma jet processing on the quality of mangosteen juice using an experimental design that varied the duty cycle of the power source (30%–70%), air flow rate (1–5 L/min), and treatment time (2–10 min). Changes in pH, color, ascorbic acid (AA), anthocyanin, flavonoid, phenolic content, enzyme activities, and antioxidant activity were evaluated. The cold plasma jet treatment substantially inactivated polyphenol oxidase, reducing its activity by up to 60% across all tested conditions, while peroxidase activity exhibited varying responses. The optimal treatment conditions (60% duty cycle, 4 L/min air flow rate, and 4 min treatment time) maximized bioactive compound levels, resulting in an 87.75% increase in AA content, along with substantial increases in total anthocyanins, phenolic content, and flavonoids. Cold plasma jet improved antioxidant activity, particularly in the DPPH radical scavenging activity. No notable change in color was observed. This study highlights the effectiveness of cold plasma technology for processing mangosteen juice while preserving its essential nutritional and physical qualities. The method offers a promising nonthermal alternative for maintaining the quality of high-value processing-sensitive mangosteen juice.

Unveiling the future: A simulation and analysis of hydrogen production using 1kW electrolyzer with MATLAB approach

This research concentrates on optimizing hydrogen production via a 1kW electrolyzer powered by renewable solar energy, specifically targeting efficiency enhancement through adjusting membrane area. The rising global demand for clean energy solutions has positioned hydrogen as a pivotal element in the shift toward sustainable energy systems. Nonetheless, the efficacy of hydrogen generation via electrolysis continues to pose a challenge, particularly at reduced scales. This research involved the creation of a comprehensive simulation model utilizing MATLAB Simulink to investigate the impact of membrane area variations on hydrogen production and overall system efficiency. The simulation results indicate that optimizing the membrane area can substantially enhance hydrogen production rates. The system was capable of producing up to 2.5 kg/h of hydrogen, signifying a substantial enhancement over traditional methods. Moreover, incorporating solar energy as the principal power source diminishes environmental repercussions while guaranteeing a sustainable and clean approach to hydrogen production. This research introduces an innovative method for optimizing small-scale electrolyzers, offering insights applicable to industrial hydrogen production and the integration of renewable energy. The findings facilitate the advancement of sustainable hydrogen production technologies, consistent with international initiatives to diminish dependence on fossil fuels.