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Worldwide energy demand is increasing exponentially, presenting significant challenges for existing power generation systems to meet this demand. Enhancing energy efficiency has become critical for reducing consumption and addressing the ongoing environmental crisis. Consequently, there is a need for smart control systems that optimize system costs and improve efficiency. Because of the introduction of smart grids, customers can now participate in demand-side management and integrate renewable energy sources (RESs). Electricity consumption during peak hours often leads to increased grid demand and higher costs. However, the integration of RESs enables consumers to operate appliances during peak hours, thereby reducing reliance on grid power. Therefore, residential load management seeks to reduce power peaks and electrical energy costs. In home energy management systems (HEMS), appliance scheduling is crucial because it continually monitors appliance usage, ensuring that energy supply and demand are balanced. This research aims to optimize power usage by reducing peak loads and electricity costs through the integration of RESs, such as solar or photovoltaic (PV) systems, while considering grid limitations, PV capacity, appliance ON/OFF schedules, and time-of-use tariffs. A genetic algorithm (GA) based optimization technique was employed to evaluate the performance of a HEMS and validated with particle swarm optimization (PSO) technique under identical initial conditions for each appliance and their corresponding energy pricing over different periods. The results show that GA achieved a 48% cost reduction compared to PSO, with significant peak load reduction and improved energy optimization when integrated with PV systems. GA also demonstrated better appliance scheduling, with appliances in the “ON” state for 82% of the time, compared to 52% with PSO.

Reliable and cost-effective electricity generation has been a significant problem for many years. Economic dispatch (ED) techniques have been widely used for efficient power production at minimal cost. However, conventional ED techniques have been studied considering only traditional power plants. With the depletion of fossil fuels and rising environmental concerns, many countries are shifting toward maximizing the share of renewable energy resources in their energy mix. The dispatch strategies should consider both conventional and renewable energy systems to align with this transition. Therefore, in this study, the ED of a system comprising 13 photovoltaic (PV) plants and 10 thermal generators is optimized using the binary artificial bee colony technique within a combined economic and emission dispatch (CEED) framework. Only selected expenditures, fuel and emission charges for thermal units, and the per-unit expense of PV power are considered. Moreover, both full solar radiation and reduced radiation conditions, simulating cloudy weather, are included in the CEED framework. The results demonstrate that the proposed algorithm gives satisfactory outputs, capping the PV share to 25% to maintain grid stability and leverage renewable energy benefits. Furthermore, the proposed algorithm is compared with particle swarm optimization (PSO) within the CEED framework. The comparative analysis depicts that the proposed algorithm reports less computational time than PSO.

Electric vehicles (EVs) play a crucial role in achieving sustainability goals, mitigating energy crises, and reducing air pollution. However, their rapid adoption poses significant challenges to the power grid, particularly during peak charging periods, necessitating advanced load management strategies. This study introduces an artificial intelligence (AI)-integrated optimal charging framework designed to facilitate fast charging and mitigate grid stress by smoothing the “duck curve”. Data from Caltech’s Adaptive Charging Network (ACN) at the National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory (JPL) site was collected and categorized into day and night patterns to predict charging duration based on key features, including start charging time and energy requested. The AI-driven charging strategy developed optimizes energy management, reduces peak loads, and alleviates grid strain. Additionally, the study evaluates the impact of integrating 1.5 million, 3 million, and 5 million EVs under various AI-based charging strategies, demonstrating the framework’s effectiveness in managing large-scale EV adoption. The peak power consumption reaches around 22,000 MW without EVs, 25,000 MW for 1.5 million EVs, 28,000 MW for 3 million EVs, and 35,000 MW for 5 million EVs without any charging strategy. By implementing an AI-driven optimal charging optimization strategy that considers both early charging and duck curve smoothing, the peak demand is reduced by approximately 16% for 1.5 million EVs, 21.43% for 3 million EVs, and 34.29% for 5 million EVs.

The ever-increasing electricity demand, its dependency on fossil fuels, and the consequent environmental degradation are major concerns of this era. The worldwide domination of fossil fuels in bulk electricity generation is rapidly increasing the emissions of CO2 and other environmentally dangerous gases that are contributing to climate change. The economic and emission dispatch are two important problems in thermal power generation whose combination produces a complex highly constrained nonlinear optimization problem known as combined economic and emission dispatch. The optimization of combined economic and emission dispatch aims to allocate the generation of committed units to minimize fuel cost and emissions, simultaneously while honoring all equality and inequality constraints. Therefore, in this article, we investigate a solution of the combined economic and emission dispatch problem using quantum particle swarm optimization and its two modified versions, that is, enhanced quantum particle swarm optimization and quantum particle swarm optimization integrated with weighted mean personal best and adaptive local attractor. The enhanced quantum particle swarm optimization algorithm achieves particles’ diversification at early stages and shows good performance in local search at later stages. The quantum particle swarm optimization integrated with weighted mean personal best and adaptive local attractor boosts search performance of quantum particle swarm optimization and attains better global optimality. The suggested methods are employed to achieve solution for the combined economic and emission dispatch in four distinct systems, encompassing two scenarios with 6 units each, one with a 10-unit configuration, and another with an 11-unit setup. A comparative analysis with methodologies documented in existing literature reveals that the proposed approach outperforms others, demonstrating superior computational performance and robust efficiency.

Micro-accelerometers are in high demand across many due to their compact size, low energy consumption, and excellent precision. Since gravity causes a large movement when the device is positioned vertically, measuring low gravitational acceleration is challenging. This study examines the intrinsic relationship between applied voltage levels and displacement in micro-accelerometers. The study introduces a novel design that integrates hybrid flexures, comprising both linear and angular configurations, with an out-of-plane overlap varying (OPOV) electrostatic actuation mechanism. This design aims to measure the micro-accelerometer’s movement and low frequency response. The proposed device with silicon material is designed and simulated using the IntelliSuite® software, considering its small dimensions and 25 µm thickness. The norm value of 28.0916 μN from gravity’s reaction forces on the body, a resonant frequency of 179.668 Hz at the first desired mode, and a maximum stress of 24.7 MPa were obtained through the electro-mechanical analysis. A comparison of the proposed design was conducted with other configurations, measuring a frequency of 179.668 Hz at a minimum downward displacement of 7.69916 µm under the influence of gravity without electrostatic mechanisms. Following this, an electrostatic actuation mechanism was introduced to minimize displacement by applying different voltage levels, including 1 V, 1.5 V, and 3 V. At 3 V, a significant improvement in displacement reduction was observed compared to the other applied voltages. Additionally, dynamic and sensitivity analyses were carried out to validate the performance of the proposed design further.

The abundance of powered semiconductor devices has increased with the introduction of renewable energy sources into the grid, causing power quality disturbances (PQDs). This represents a huge challenge for grid reliability and smart city infrastructures. Accurate detection and classification are important for grid reliability and consumers’ appliances in a smart city environment. Conventionally, power quality monitoring relies on trivial machine learning classifiers or signal processing methods. However, recent advancements have introduced Deep Convolution Neural Networks (DCNNs) as promising methods for the detection and classification of PQDs. These techniques have the potential to demonstrate high classification accuracy, making them a more appropriate choice for real-time operations in a smart city framework. This paper presents a voting ensemble approach to classify sixteen PQDs, using the DCNN architecture through transfer learning. In this process, continuous wavelet transform (CWT) is employed to convert one-dimensional (1-D) PQD signals into time–frequency images. Four pre-trained DCNN architectures, i.e., Residual Network-50 (ResNet-50), Visual Geometry Group-16 (VGG-16), AlexNet and SqeezeNet are trained and implemented in MATLAB, using images of four datasets, i.e., without noise, 20 dB noise, 30 dB noise and random noise. Additionally, we also tested the performance of ResNet-50 with a squeeze-and-excitation (SE) mechanism. It was observed that ResNet-50 with the SE mechanism has a better classification accuracy; however, it causes computational overheads. The classification performance is enhanced by using the voting ensemble model. The results indicate that the proposed scheme improved the accuracy (99.98%), precision (99.97%), recall (99.80%) and F1-score (99.85%). As an outcome of this work, it is demonstrated that ResNet-50 with the SE mechanism is a viable choice as a single classification model, while an ensemble approach further increases the generalized performance for PQD classification.

Oxidative coupling of methane and methane dehydroaromatization are attractive one-step conversion routes to make valuable platform chemicals more sustainable. Both processes require elevated temperatures above 600°C, good heat management, and the use of heterogeneous catalysts. None of these reactions are yet commercial due to many technical challenges. This work explores the potential of combining these two processes under one umbrella to overcome some of the technical challenges and make these processes more attractive. It focuses on the recuperative autothermal reactor coupling as one of the possible integration options. A tube-in-tube reactor design is proposed in which OCM is in the inner tube and MDA is in the outside. A numerical study is carried out using pseudohomogenous ideal fixed bed reactor models with literature kinetics. A systematic tabulated approach is used to simplify, visualize, and structure the design process and view the design options. Practical constraints such as reactor sizing, pressure drop, reaction performance, and axial temperature profile are investigated. The effect of heat transfer coefficient, diluents, catalyst profiling, and flow direction have been investigated to alter the axial temperature profile, avoid thermal run away, and improve the performance. Multiple thermally coupled OCM-MDA reactor design candidates are identified. This is the first time that the thermal coupling of OCM and MDA has been identified and quantified. These candidates are merely a starting point toward exploring the full coupling opportunities between OCM and MDA toward reaching the ultimate and more attractive option of full mass and heat integration in the same reactor.

Vibration based energy harvesting techniques play important role to minimize external power source requirements and maintenance for electric devices such as wireless sensor networks. Vibration Energy harvesters (VEH) can be developed mainly on the basis of transduction principle of Electromagnetic, Piezoelectric and Electrostatic. Electrostatic energy harvester provides high output voltage, cost effectiveness, easy adjustment of coupling coefficient and increase in capacitance due to size reduction. Design and simulation analysis of electrostatic energy harvester are main objectives of this research. Two designs of electrostatic energy harvesters A & B are presented in this thesis. Design A is made up of In-plane gap closing (IPGC) and In-plane overlap varying (IPOV) converters. Design B, which is main required design of this research, is made up of IPOV, IPGC and In-plane patterned varying (IPPV) converters. Comparison is performed between two designs and results obtained through simulation analysis shows that our required design B is more efficient and reliable as compare to design A with respect to output power and power density. IntelliSuite® software is used for designing and simulation analysis in this thesis. Three simulation analysis including electrostatic, mechanical and electromechanical analysis are performed on both designs. Frequency of design A and B obtained through simulation analysis is almost 19.1 KHz and 21.7 KHz respectively. Harvested output power of design A (IPOV, IPGC) and design B (IPOV, IPGC & IPPV) is 0.472 mW and 0.496 Mw respectively. Power density of design A & B is 355.6 mW/mm3 and 374.4 mW/mm3 respectively.

Power losses in electrical power systems especially, distribution systems, occur due to several environmental and technical factors. Transmission & Distribution line losses are normally 17% and 50% respectively. These losses are due to the inappropriate size of the conductor, long distribution lines, low power factor, overloading of lines etc. The power losses cause economic loss and reduce the system's reliability. The reliability of electrical power systems can be improved by decreasing network power loss and by improving the voltage profile. In radial distribution systems, power loss can also be minimized through Distributed Generation (DG) system placement. In this thesis, three different grid strategies including real power sharing, reactive power injection and transformer tap changing are discussed and used to minimize line losses. These three proposed grid strategies have been implemented using a power flow study based on Newton-Raphson (NR) and Genetic Algorithm (GA). To minimize line losses, both methods have been used for each grid strategy. The used test system in this research work is the IEEE-30 bus radial distribution system. Results obtained after simulation of each grid strategy using NR and GA shows that real load sharing is reliable with respect to minimization of line loss as compared to reactive power injection and transformer tap changing grid strategy. Comparative analysis has been performed between GA and NR for each grid strategy, results show that Genetic Algorithm is more reliable and efficient for loss minimization as compared to Newton-Raphson. In the base case for optimum power flow solution using genetic algorithm and Newton-Raphson, real line losses are 9.481475MW and 17.557MW respectively. So, GA is preferable for each proposed grid strategy to minimize line losses than NR.

In this paper, we introduce Writing in the Margins (WiM), a new inference pattern for Large Language Models designed to optimize the handling of long input sequences in retrieval-oriented tasks. This approach leverages the chunked prefill of the key-value cache to perform segment-wise inference, which enables efficient processing of extensive contexts along with the generation and classification of intermediate information (\"margins\") that guide the model towards specific tasks. This method increases computational overhead marginally while significantly enhancing the performance of off-the-shelf models without the need for fine-tuning. Specifically, we observe that WiM provides an average enhancement of 7.5% in accuracy for reasoning skills (HotpotQA, MultiHop-RAG) and more than a 30.0% increase in the F1-score for aggregation tasks (CWE). Additionally, we show how the proposed pattern fits into an interactive retrieval design that provides end-users with ongoing updates about the progress of context processing, and pinpoints the integration of relevant information into the final response. We release our implementation of WiM using Hugging Face Transformers library at https://github.com/writer/writing-in-the-margins.