The increasing usage of perovskite solar cells is being driven by their high efficiency and cost-effective manufacture. Polyethylene Terephthalate (PET) and Polyethylene Naphthalate (PEN) are flexible, transparent, an...
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Transmission expansion planning (TEP) is crucial for maintaining the reliable and efficient operation of the power systems, particularly in the face of increasing electricity demand and the integration of renewable en...
Transmission expansion planning (TEP) is crucial for maintaining the reliable and efficient operation of the power systems, particularly in the face of increasing electricity demand and the integration of renewable energy sources. This paper aims to investigate the application of unconventional high surge impedance loading (HSIL) lines in TEP and presents a comparative analysis of their outcomes against conventional line-based TEP approaches. Starting with a 17-bus 500 kV test system, which can operate well under normal operating condition as well as all single contingency conditions, the objective is to connect a new load located in a new bus, bus #18, to the existing test system via two approaches: using conventional lines and incorporating unconventional HSIL lines. By comparing the number of lines required for the conventional and unconventional approaches, maintaining identical conductor weight per circuit, the effectiveness of unconventional HSIL lines in TEP is evaluated where using only two unconventional HSIL lines is sufficient to connect 1250 MW load demand at bus 18 while three transmission lines are required when using the conventional line. Finally, a thorough economic analysis has been conducted on both TEP scenarios, revealing that implementing unconventional HSIL lines leads to remarkable cost savings and thus can be considered a promising option for TEP studies.
In this work, we study the problem of decentralized multi-agent perimeter defense that asks for computing actions for defenders with local perceptions and communications to maximize the capture of intruders. One major...
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The electric field intensity on subconductors is the most important parameter to consider when electrically designing (extra) high voltage, (E)HV, transmission lines. In this regard, it is not possible to use existing...
The electric field intensity on subconductors is the most important parameter to consider when electrically designing (extra) high voltage, (E)HV, transmission lines. In this regard, it is not possible to use existing formulae for calculating electric field intensity on subconductors, which are for subconductors placed symmetrically on bundle circles, for recently introduced unconventional high power density lines where subconductors can be located in unsymmetrical or at any location in the space. Further, in existing formulas, nearby (other phases) and image conductors are ignored, and a uniform field is assumed despite the fact that electric fields are distorted in the presence of other subconductors in a bundle. None of the mentioned assumptions are valid for unconventional high power density lines, so it is necessary to develop an innovative method for calculating electric field on subconductors on these new lines. In our method, $n_{m}$ line charges for each subconductor are employed to set the electric potentials of $n_{m}$ points at the periphery of that subconductor equal to the applied voltage. The line charges are uniformly distributed around a hypothetical cylinder with a radius of $r/2$ , where $r$ is the radius of that subconductor. The challenge is choosing a proper $n_{m}$ , leading to an accurate result.
This paper describes a monitoring/inspection technique for the estimation of longitudinal stress in continuous welded rails (CWR) to infer the rail neutral temperature (RNT), i.e. the temperature at which the net long...
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Federated Learning (FL) has emerged as a promising framework for distributed training of AI-based services, applications, and network procedures in 6G. One of the major challenges affecting the performance and efficie...
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Parasitic capacitance of dc/dc transformers interfacing the cascaded H-Bridge (CHB) converter can introduce extra switching losses. A switching loss reduction method with diode clamped grounding for dc/dc transformers...
Parasitic capacitance of dc/dc transformers interfacing the cascaded H-Bridge (CHB) converter can introduce extra switching losses. A switching loss reduction method with diode clamped grounding for dc/dc transformers connecting CHB is proposed in this paper. The transformer grounding is connected to diode clamping circuit on the low voltage dc link to partially cancel the voltage charging/discharging the parasitic capacitances. Simulation and test have been demonstrated that the proposed method has reduced 53% of the parasitics induced loss and $\sim$ 6% of the total converter loss in the setup with one simple diode half-bridge clamping circuit added on each converter cell.
The future sixth-generation (6G) of wireless networks is expected to surpass its predecessors by offering ubiquitous coverage through integrated air-ground facility deployments in both communication and computing doma...
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The future sixth-generation (6G) of wireless networks is expected to surpass its predecessors by offering ubiquitous coverage through integrated air-ground facility deployments in both communication and computing domains. In this network, aerial facilities, such as unmanned aerial vehicles (UAVs), conduct artificial intelligence (AI) computations based on multi-modal data to support diverse applications including surveillance and environment construction. However, these multi-domain inference and content generation tasks require large AI models, demanding powerful computing capabilities and finely tuned inference models trained on rich datasets, thus posing significant challenges for UAVs. To tackle this problem, we propose an integrated air-ground edge-cloud model evolution framework, where UAVs serve as edge nodes for data collection and small model computation. Through wireless channels, UAVs collaborate with ground cloud servers, providing large model computation and model updating for edge UAVs. With limited wireless communication bandwidth, the proposed framework faces the challenge of information exchange scheduling between the edge UAVs and the cloud server. To tackle this, we present joint task allocation, transmission resource allocation, transmission data quantization design, and edge model update design to enhance the inference accuracy of the integrated air-ground edge-cloud model evolution framework by mean average precision (mAP) maximization. A closed-form lower bound on the mAP of the proposed framework is derived based on the mAP of the edge model and mAP of the cloud model, and the solution to the mAP maximization problem is optimized accordingly. Simulations, based on results from vision-based classification experiments, consistently demonstrate that the mAP of the proposed integrated air-ground edge-cloud model evolution framework outperforms both a centralized cloud model framework and a distributed edge model framework across various communica
Underfrequency load shedding (UFLS) schemes are traditionally implemented in two ways. One approach is based on manual load shedding implemented by system operators. The second approach is automatic load shedding, imp...
Underfrequency load shedding (UFLS) schemes are traditionally implemented in two ways. One approach is based on manual load shedding implemented by system operators. The second approach is automatic load shedding, implemented through underfrequency relays. The main limitation of traditional load shedding schemes is that they are reactive and leave little room for optimized corrective actions. This work presents a proactive and automatic underfrequency load shedding framework for power systems. Measurements are captured via phasor measurement units (PMUs) at relatively low rates of 30 fps. These measurements are then processed by a particle filter which predicts the future state of frequency. Based on these predictions excess loading is determined and shed. Comparative case studies are performed via simulations. Easy-to-implement models, without hard-to-derive parameters, highlight the potential for real-life implementation.
We find limits to the Transformer architecture for language modeling and show it has a universal prediction property in an information-theoretic sense. We further analyze performance in non-asymptotic data regimes to ...
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