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International Conference on Information Technology (INCIT)

作者： Somkuan Srisawat Ravee Phromloungsri Apichan Kanjanavapastit Kritsanapong Somsuk Somchat Sonasang Mitchai Chongcheawchamnan Computer and Communication Engineering Faculty of Technology Udon Thani Rajabhat University Udon Thani Thailand Electrical Elements and Wireless Devices Unit (EEWDU) Faculty Industrial Technology Nakhon Phanom University Nakhon Phanom Thailand Electrical Engineering Prince of Songkla University Songkhla Thailand

ISBN: (数字)9798350366303

ISBN: (纸本)9798350366310

This paper presents the design and implementation of an S-band Rat Race Hybrid Coupler operating at 2.2-2.3 GHz, integrated with parallel coupled-line phase shifters to reduce circuit size for satellite communication systems. The proposed design improves critical performance parameters, including phase balance, insertion loss, isolation, and bandwidth. The design achieves enhanced isolation and bandwidth by incorporating the coupled-line phase shifter into the traditional rat-race structure, making it suitable for applications in signal processing, antenna-feeding networks, and radar systems. Simulations using a 70.7-Ω microstrip line at 2.25 GHz demonstrate significant improvements in phase shift accuracy and return loss. Measurement results validate the simulations, confirming the compact and efficient nature of the design, which offers promising potential for modern microwave communication technologies.

关键词： Microwave measurement Microwave antennas Antenna measurements Spaceborne radar Phase shifters Couplers Rats Microwave communication Radar antennas Microwave circuits

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Robust Stochastic Shortest-Path Planning via Risk-Sensitive Incremental Sampling

arXiv

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arXiv 2024年

作者： Enwerem, Clinton Noorani, Erfaun Baras, John S. Sadler, Brian M. The Department of Electrical & Computer Engineering The Institute for Systems Research University of Maryland College ParkMD United States The University of Texas AustinTX United States

With the pervasiveness of Stochastic Shortest-Path (SSP) problems in high-risk industries, such as last-mile autonomous delivery and supply chain management, robust planning algorithms are crucial for ensuring successful task completion while mitigating hazardous outcomes. Mainstream chance-constrained incremental sampling techniques for solving SSP problems tend to be overly conservative and typically do not consider the likelihood of undesirable tail events. We propose an alternative risk-aware approach inspired by the asymptotically-optimal Rapidly-Exploring Random Trees (RRT*) planning algorithm, which selects nodes along path segments with minimal Conditional Value-at-Risk (CVaR). Our motivation rests on the step-wise coherence of the CVaR risk measure and the optimal substructure of the SSP problem. Thus, optimizing with respect to the CVaR at each sampling iteration necessarily leads to an optimal path in the limit of the sample size. We validate our approach via numerical path planning experiments in a two-dimensional grid world with obstacles and stochastic path-segment lengths. Our simulation results show that incorporating risk into the tree growth process yields paths with lengths that are significantly less sensitive to variations in the noise parameter, or equivalently, paths that are more robust to environmental uncertainty. Algorithmic analyses reveal similar query time and memory space complexity to the baseline RRT* procedure, with only a marginal increase in processing time. This increase is offset by significantly lower noise sensitivity and reduced planner failure rates. © 2024, CC BY.

关键词： Stochastic systems

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TVCondNet: A Conditional Denoising Neural Network for NMR Spectroscopy

arXiv

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arXiv 2024年

作者： Zou, Zihao Shoushtari, Shirin Liu, Jiaming Zhang, Jialiang Judge, Patrick Santana, Emilia Lim, Alison Foston, Marcus Kamilov, Ulugbek S. The Department of Electrical & Systems Engineering Washington University in St. Louis St. LouisMO63130 United States The Department of Computer Science & Engineering The Department of Electrical & Systems Engineering Washington University in St. Louis St. LouisMO63130 United States The Department of Energy Environmental & Chemical Engineering Washington University St. LouisMO63130 United States

Nuclear Magnetic Resonance (NMR) spectroscopy is a widely-used technique in the fields of bio-medicine, chemistry, and biology for the analysis of chemicals and proteins. The signals from NMR spectroscopy often have low signal-to-noise ratio (SNR) due to acquisition noise, which poses significant challenges for subsequent analysis. Recent work has explored the potential of deep learning (DL) for NMR denoising, showing significant performance gains over traditional methods such as total variation (TV) denoising. This paper shows that the performance of DL denoising for NMR can be further improved by combining data-driven training with traditional TV denoising. The proposed TVCondNet method outperforms both traditional TV and DL methods by including the TV solution as a condition during DL training. Our validation on experimentally collected NMR data shows the superior denoising performance and faster inference speed of TVCondNet compared to existing methods. © 2024, CC BY-NC-SA.

关键词： Nuclear magnetic resonance spectroscopy

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Volt-Var Control for Utility-scale Solar PV Plants to Replace SVCs

Volt-Var Control for Utility-scale Solar PV Plants to Replac...

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International Conference on High Voltage engineering and Power systems (ICHVEPS)

作者： Ken Shimomukai Haruka Maeda Goro Fujita Functional Control Systems Graduate School of Engineering and Science Shibaura Institute of Technology Tokyo Japan Department of Electrical Engineering and Computer Science Graduate School of Engineering and Science Shibaura Institute of Technology Tokyo Japan Department of Electrical Engineering Shibaura Institute of Technology Tokyo Japan

One way to increase solar photovoltaic penetration in the grid is management of voltage fluctuations. This is because a photovoltaic plant cannot be interconnected to the grid if it causes voltage violations. Voltage violation is where voltage exceeds the acceptable range. Often, grid operators request photovoltaic plant owners to regulate voltage sufficiently with expensive and space-consuming static Var compensators. Unfortunately, this sometimes makes the project less feasible. This paper argues that there are better ways to regulate voltage. We ran a simulation with a 70 MWp photovoltaic plant as an addition to the grid. Without voltage regulation, voltage violations were found to be significant. This paper found that oversizing the inverter sufficiently would remove all voltage violations without deploying a static Var compensator. This is often a cheaper and space-saving solution for voltage management. This paper argues that economics and spatial efficiency of reactive power compensation devices is key to increasing photovoltaic penetration.

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Review of Planning and Optimization of the Renewable-Energy-Based Micro-Grid for Rural Electrification

Review of Planning and Optimization of the Renewable-Energy-...

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Power engineering Conference (SAUPEC), Southern African Universities

作者： Nteka Mojela Maletsie Senthil Krishnamurthy Department of Electrical Electronic and Computer Engineering Centre for Substation Automation and Energy Management Systems Cape Peninsula University of Technology Bellville Cape Town South Africa

The research work provides a comprehensive overview of the challenges and opportunities in the current energy landscape, particularly focusing on the role of microgrids in addressing the issues associated with the increasing energy demand, population growth, and technological advancements. The review addresses the rapid urbanization and population growth, coupled with technological advancements, have indeed led to an upsurge in energy demand globally. As suburban areas expand quickly, the demand for electricity in these regions rises, and traditional power grids may struggle to keep up with the increasing load. The mismatch between energy demand and generation poses a significant challenge. This can lead to power systems operating close to their limits, making them susceptible to disturbances and outages. The vulnerability of power system models to disturbances highlights the need for more resilient and adaptive energy solutions. Therefore optimal renewable-based microgrids are proposed as a promising alternative to reduce dependency on centralized power grids. Microgrids can enhance energy reliability, efficiency, and sustainability, particularly in areas where traditional grid infrastructure is lacking. Microgrids are identified as a solution for rural electrification, addressing both economic feasibility and long-term stability. The study aims to review the techno-economic aspects of microgrids, including the sizing and integration of Renewable Energy Sources (RES). The review addresses research gaps and implies a need for further exploration and development in microgrid-based energy management systems. Identifying and addressing these gaps will contribute to the effectiveness and efficiency of rural electrification. In summary, the study aims to provide a review summary of insights into the challenges and solutions associated with rural electrification through microgrids, emphasizing the importance of renewable energy sources and efficient energy management tech

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Towards Near Real-time Digital Twins of Construction Sites: Developing High LOD 4D Simulation Based on computer Vision and RTLS 38

Towards Near Real-time Digital Twins of Construction Sites: ...

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38th International Symposium on Automation and Robotics in Construction, ISARC 2021

作者： Huang, Yusheng Hammad, Amin Torabi, Ghazaleh Ghelmani, Ali Guevremont, Michel Department of Building Civil and Environmental Engineering Concordia University Canada Concordia Institute of Information Systems Engineering Concordia University Canada Department of Electrical and Computer Engineering Concordia University Canada

ISBN: (纸本)9789526952413

4D simulation can be used in the planning phase of a project for constructability analysis, which aims to optimize construction processes and improve safety management. The same 4D simulation can be used as a digital twin in the construction phase for progress monitoring and identifying potential safety issues based on micro-schedules. A micro-schedule is a schedule listing tasks of short durations (i.e., days or hours) with the information of the resources assigned to each task (i.e., workers, equipment and materials). The site data can be collected using computer Vision (CV) or Real-Time Location systems (RTLS) to identify and recognize the activities of construction resources, as well as to capture the progress of the project. This paper aims to explore the possibility of developing near real-time digital twins of construction sites. The digital twin is developed as a high Level of Development (LOD) 4D Simulation based on CV and RTLS data. A case study is performed to investigate the proposed method. © 2021 Proceedings of the International Symposium on Automation and Robotics in Construction. All rights reserved.

关键词： computer vision

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Flight Risk Assessment of Urban Air Mobility Vehicles and Routes Based on Battery Energy Consumption

Flight Risk Assessment of Urban Air Mobility Vehicles and Ro...

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Conference on Digital Avionics systems (DASC)

作者： Yonas Ayalew Abdul-Rauf Nuhu Lydia Zeleke Vahid Hemmati Abdollah Homaifar Edward Tunstel Department of Electrical and Computer Engineering North Carolina A&T State University NC USA Motiv Space Systems Inc. Pasadena CA USA

ISBN: (数字)9798350349610

ISBN: (纸本)9798350349627

This paper presents a flight risk assessment framework for Urban Air Mobility (UAM) vehicles and routes. It considers separation automation and mission structure sensitivity based on energy demand. We evaluate the energy consumption of a conceptual hexacopter electric Vertical Takeoff and Landing (eVTOL) vehicle for identified potential UAM routes from Dallas-Fort Worth and San Francisco metropolitan regions considering level flight conflict management. A mission structure-based parameter sensitivity study is conducted for operational flexibility, and assessment of associated risk level, of the UAM vehicle's flight energy consumption using Conditional Value at Risk (CVaR) statistical metrics. Our results demonstrate that the feasibility and energy demand of the flights can be affected greatly by the vehicle configuration, range of the operational routes, aircraft density in the airspace, conflicts, and different parameter values of the mission structure. This study high-lights the fact that a mission parameter-based energy demand evaluation that considers performance-based energy reserve can provide information about possible vehicle capabilities in a specific operation. Additionally, the CVaR metric captured the maximum level of risk associated with high energy-demanding flights for the potential routes in the two metropolitan regions. These findings provide air transportation decision-makers with crucial insights for enhancing strategies aimed at accelerating the design-to-certification process of UAM vehicles and mitigating operational hazards.

关键词： Energy consumption Reactive power Sensitivity Urban areas Probability Hazards Risk management Aircraft Payloads Guidelines

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Performance Analysis of Hybrid Power Plant under Varying Grid Conditions

Performance Analysis of Hybrid Power Plant under Varying Gri...

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Australasian Universities Power engineering Conference, AUPEC

作者： Ashan Imantha M. H. Bandara Fatemeh Shahnazian Ruifeng Yan Tapan Kumar Saha UQ School of Electrical Engineering and Computer Science University of Queensland Brisbane Australia Department of Wind and Energy Systems Technical University of Denmark (DTU) Roskilde Denmark

ISBN: (数字)9798350377941

ISBN: (纸本)9798350377958

Large synchronous generators are being retired, while inverter-based renewable energy sources (IBR) are increasing, weakening future power system strength. As the grid weakens, grid-following (GFL) IBRs may become unstable. However, grid-forming (GFM) IBRs can reinforce weak grids, ensuring stability. Hybrid power plants (HPPs) with GFM and GFL can operate in very weak grids. However, the dynamic differences of IBR plants complicate interactions between plant-level controllers in HPPs. This study uses advanced modelling and time-domain simulations to examine HPP dynamic behaviour under various grid strengths. An HPP with three IBR power plants is used to evaluate the centralised, hierarchical control system under different system strengths and X/R ratios. The HPP’s stability boundary is maintained across different system strengths. The findings improve our understanding of the interactions between the HPP and the grid and support optimised design and operation strategies for future energy systems.

关键词： Reactive power Grid following Power system dynamics Power system stability Stability analysis Hybrid power systems Synchronous generators Time-domain analysis Power generation Grid forming

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Frequency Domain Auto-tuning of Structured LPV Controllers for High-Precision Motion Control

Frequency Domain Auto-tuning of Structured LPV Controllers f...

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IEEE Conference on Decision and Control

作者： Yorick Broens Hans Butler Roland Tóth Department of Electrical Engineering Eindhoven University of Technology Eindhoven The Netherlands ASML Veldhoven The Netherlands Systems and Control Laboratory HUNREN Institute for Computer Science and Control Hungary

ISBN: (数字)9798350316339

ISBN: (纸本)9798350316346

Motion systems are a vital part of many industrial processes. However, meeting the increasingly stringent demands of these systems, especially concerning precision and throughput, requires novel control design methods that can go beyond the capabilities of traditional solutions. Traditional control methods often struggle with the complexity and position-dependent effects inherent in modern motion systems, leading to compromises in performance and a laborious task of controller design. This paper addresses these challenges by introducing a novel structured feedback control auto-tuning approach for multiple-input multiple-output (MIMO) motion systems. By leveraging frequency response function (FRF) estimates and the linear-parameter-varying (LPV) control framework, the proposed approach automates the controller design, while providing local stability and performance guarantees. Key innovations include norm-based magnitude optimization of the sensitivity functions, an automated stability check through a novel extended factorized Nyquist criterion, a modular structured MIMO LPV controller parameterization, and a controller discretization approach which preserves the continuous-time (CT) controller parameterization. The proposed approach is validated through experiments using a state-of-the-art moving-magnet planar actuator prototype.

关键词： Technological innovation Sensitivity Frequency-domain analysis Stability criteria Prototypes Throughput Frequency response Motion control Optimization MIMO communication

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IoT-based ELF Magnetic Flux Density Meter

IoT-based ELF Magnetic Flux Density Meter

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International Conference on Control, Artificial Intelligence, Robotics & Optimization (ICCAIRO)

作者： Manolis G. Tampouratzis George A. Adamidis Demosthenes Vouyioukas Traianos Yioultsis Dimitrios Stratakis Department of Information and Communication Systems Engineering University of the Aegean Karlovasi Greece Department of Electronics Engineering Hellenic Mediterranean University (HMU) Chania Greece Department of Electrical and Computer Engineering (ECE) Aristotle University of Thessaloniki (AUTH) Thessaloniki Greece Department of Electrical and Computer Engineering (ECE) Hellenic Mediterranean University (HMU) Heraklion Greece

This study presents an IoT-based ELF magnetic field meter that can measure magnetic flux density from 100nT. The proposed device has a flat response across the frequency range from 40Hz to 10 KHz, detecting and measuring most magnetic field sources. The proposed meter can measure fields from the power supply network (usually 50 or 60Hz) and harmonic frequencies extending several times above the base frequency in the operating frequency band. The proposed circuit of the magnetic flux density (magnetic field) meter is quite simple for implementation and the measured field can be displayed on any mobile device with Wi-Fi connectivity. A WeMos D1 Arduino board with an embedded ESP-8266 module is responsible for data transferring from the sensor to the cloud as a complete IoT solution, supported by the Blynk application via Android and iOS operating systems or web interface.

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