62 research outputs found

    Regulatory islanding parameters in battery based solar PV for electricity system resiliency

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    Distributed battery based solar power photovoltaic (PV) systems have the potential to supply electricity during grid outages resulting from extreme weather or other emergency situations. As such, distributed PV can significantly increase the resiliency of the electricity system. In order to take advantage of this capability, however, the PV systems must be designed with regulatory parameters in mind and combined with other technologies, such as smart energy storage and auxiliary generation. Strengthening policy and regulatory support could encourage deployment of PV systems designed for resiliency and improve public safety to power during emergencies. This paper specifies the goals of power resiliency and explains the reasons that most distributed PV systems as installed today in the United States are technically incapable of providing consumer power during a grid outage. It presents the basics and regulatory parameters of designing distributed PV systems for resiliency, including the use of energy storage and Microgrids. The paper concludes with critical policy and regulatory considerations for encouraging the use of these distributed system designs

    Regulatory islanding parameters in battery based solar PV for electricity system resiliency

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    Distributed battery based solar power photovoltaic (PV) systems have the potential to supply electricity during grid outages resulting from extreme weather or other emergency situations. As such, distributed PV can significantly increase the resiliency of the electricity system. In order to take advantage of this capability, however, the PV systems must be designed with regulatory parameters in mind and combined with other technologies, such as smart energy storage and auxiliary generation. Strengthening policy and regulatory support could encourage deployment of PV systems designed for resiliency and improve public safety to power during emergencies. This paper specifies the goals of power resiliency and explains the reasons that most distributed PV systems as installed today in the United States are technically incapable of providing consumer power during a grid outage. It presents the basics and regulatory parameters of designing distributed PV systems for resiliency, including the use of energy storage and Microgrids. The paper concludes with critical policy and regulatory considerations for encouraging the use of these distributed system designs

    HAPTIC SCULPTING AND 5-AXIS PENCIL-CUT PLANNING IN VIRTUAL PROTOTYPING AND MANUFACTURING

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    ABSTRACT In this paper, a Two-phase approach to tool collision detection and local gouging elimination is proposed for haptic pencil-cut of sculptured surfaces. Pencil-cut is a special kind of machining operation, whose purpose is to use relatively smaller tools to remove rest material on the corners or highly curved regions that are inaccessible by bigger tools. Tool orientation determination and tool collision avoidance are critical issues for 5-axis pencil-cut tool path planning. Detailed techniques of haptic rendering and tool interference avoidance are discussed for haptic-aided 5-axis pencil-cut tool path generation. Hardware and software implementation of the haptic pencil-cut system with practical examples are also presented in this paper

    A Preliminary Model of Regulating Natural Capital Funds for Renewable Energy

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    Abstract. Framing sustainable environmental laws in regulating Natural Capital funds for Renewable Energy (RE) is central to the discussion on sustainability strategies. Natural Capital is that limited form of capital assets or service (tangible or intangible) that satisfies basic and social conditions for human existence and protection. This paper proposes an analytical regulatory model utilizing Neural Network (NN) of substantive and procedural issues framing the regulatory parameters associated with Natural capital funding. The model recognizes the fact that the purpose of any legal system is not only to assign duties and responsibilities in protecting rights of individuals and groups in their respective endeavors; but for effective modelling of natural structures as well. Through a preliminarydiscussion of European and USA markets’; regulatory systems with a focus on market and social values, it attempts to discern a practical model to formulate social and regulatory measures on financial structures and energy matters that are considered rights and obligations of individuals and organizations in conducting their businesses. As it has been a subject of academic, government, and public discussions with intense controversies, finding the differences of methodological, and analytical foundation will most probably lead to deeper insight into regulating funds for renewable energy.Keywords. Natural capital, Sustainable, Entrepreneurial collaboration, ISO, Climate change, Neural Network (NN).JEL. N70, O13, Q40

    Soliton generation in CaF2_2 crystalline whispering gallery mode resonators with negative thermal-optical effects

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    Calcium fluoride (CaF2_2) crystalline whispering gallery mode resonators (WGMRs) exhibit ultrahigh intrinsic quality factors and a low power anomalous dispersion in the communication and mid-infrared bands, making them attractive platforms for microresonator-based comb generation. However, their unique negative thermo-optic effects pose challenges when achieving thermal equilibrium. To our knowledge, our experiments serve as the first demonstration of soliton microcombs in Q > 109 CaF2_2 WGMRs. We observed soliton mode-locking and bidirectional switching of soliton numbers caused by the negative thermo-optic effects. Additionally, various soliton formation dynamics are shown, including breathing and vibrational solitons, which can be attributed to thermo-photomechanical oscillations. Thus, our results enrich the soliton generation platform and provide a reference for generating solitons from WGMRs that comprise other materials with negative thermo-optic effects. In the future, the ultrahigh quality factor of CaF2_2 crystal cavities may enable the generation of sub-milliwatt-level broad-spectrum soliton combs.Comment: 4 pages,5 pictures,description of soliton generation in a calcium fluoride whisper gallery mode microresonators with negative thermo-optical effect,ready for publication in optics lette

    Towards a compact soliton microcomb fully referenced on atomic reference

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    A fully stabilized soliton microcomb is critical for many applications of optical frequency comb based on microresonators. However, the current approaches for full frequency stabilization require either external acousto-optic or electro-optic devices or auxiliary lasers and multiple phase-locked loops, which compromises the convenience of the system. This study explores a compact atomic referenced fully stabilized soliton microcomb that directly uses a rubidium atomic optical frequency reference as the pump source, and complements the repetition rate (7.3 GHz) of the soliton microcomb was phase-locked to an atomic-clock-stabilized radio frequency (RF) reference by mechanically tuning the resonance of the optical resonator. The results demonstrate that the stability of the comb line (0.66 THz away from the pump line) is consistent with that of the Rb87 optical reference, attaining a level of approximately 4 Hz @100 s, corresponding to the frequency stability of 2E-14 @100 s. Furthermore,the frequency reproducibility of the comb line was evaluated over six days and it was discovered that the standard deviation (SD) of the frequency of the comb line is 10 kHz, resulting in a corresponding absolute deviation uncertainty of 1.3E-10, which is technically limited by the locking range of the soliton repetition rate. The proposed method gives a low-power and compact solution for fully stabilized soliton micorcombs.Comment: 6 pages, 5 figure

    Accurate identification and measurement of the precipitate area by two-stage deep neural networks in novel chromium-based alloys

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    The performance of advanced materials for extreme environments is underpinned by their microstructure, such as the size and distribution of nano- to micro-sized reinforcing phase(s). Chromium-based superalloys are a recently proposed alternative to conventional face-centred-cubic superalloys for high-temperature applications, e.g., Concentrated Solar Power. Their development requires the determination of precipitate volume fraction and size distribution using Electron Microscopy (EM), as these properties are crucial for the thermal stability and mechanical properties of chromium superalloys. Traditional approaches to EM image processing utilise filtering with a fixed contrast threshold, leads to weak robustness to background noise and poor generalisability to different materials. It also requires an enormous amount of time for manual object measurements on large datasets. Efficient and accurate object detection and segmentation are therefore highly desired to accelerate the development of novel materials like chromium-based superalloys. To address these bottlenecks, based on YOLOv5 and SegFormer structures, this study proposes an end-to-end, two-stage deep learning scheme, DT-SegNet, to perform object detection and segmentation for EM images. The proposed approach can thus benefit from the training efficiency of CNNs at the detection stage (i.e., a small number of training images required) and the accuracy of the ViT at the segmentation stage. Extensive numerical experiments demonstrate that the proposed DT-SegNet significantly outperforms the state-of-the-art segmentation tools offered by Weka and ilastik regarding a large number of metrics, including accuracy, precision, recall and F1-score. This model forms a useful tool to aid alloy development microstructure examinations, and offers significant advantages to address the large datasets associated with highthroughput alloy development approaches
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