The exceptional benefits of wind power as an environmentally responsible renewable energy resource have led to an increasing penetration of wind energy in today's power systems. This trend has started to reshape the paradigms of power system operations, as dealing with uncertainty caused by the highly intermittent and uncertain wind power becomes a significant issue. Motivated by this, we present a new framework using adaptive robust optimization for the economic dispatch of power systems with high level of wind penetration. In particular, we propose an adaptive robust optimization model for multi-period economic dispatch, and introduce the concept of dynamic uncertainty sets and methods to construct such sets to model temporal and spatial correlations of uncertainty. We also develop a simulation platform which combines the proposed robust economic dispatch model with statistical prediction tools in a rolling horizon framework. We have conducted extensive computational experiments on this platform using real wind data. The results are promising and demonstrate the benefits of our approach in terms of cost and reliability over existing robust optimization models as well as recent look-ahead dispatch models. Index TermsEconomic dispatch, renewable energy, adaptive robust optimization, uncertainty sets. I. INTRODUCTIONT HE exceptional benefits of wind power as an environmentally responsible energy resource have led to the rapid increase of wind energy in power systems all over the world. At the same time, wind energy possesses some characteristics drastically different from conventional generating resources in terms of high stochasticity and intermittency in production output. Due to this, deep penetration of wind power will introduce significant uncertainty to the short-term and real-time operation of power systems, in particular, to the day-ahead unit commitment (UC) and the real-time economic dispatch (ED) procedures. If the uncertainty of such variable resources is not managed properly, the system operator may have to face severe operating conditions such as insufficient ramping capabilities from the conventional generating resources due to the sudden strong loss of wind power, complicated by other contingencies, load surge, and transmission congestions [8]. These arising challenges call for new methods and models for power systems operation, and have attracted significant interests from both the electricity industry and academia.The current UC and ED procedures rely on a combination of optimization tools and operational rules. The main optimization models used for UC and ED are deterministic models, where the uncertainties, such as demand, are assumed to take nominal forecast values. To deal with unexpected contingencies and sudden demand surge, the deterministic optimization model is complemented by operational rules that require extra generation resources, the so-called reserves, to stay available for quick response. The discrepancy between the forecast and realization of uncertainty has been relatively small...

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Lithium ion batteries (LIBs) are one of the most potential energy storage devices among various rechargeable batteries due to their high energy/power density, long cycle life, and low self‐discharge properties. However, current LIBs fail to meet the ever‐increasing safety and fast charge/discharge demands. As one of the main components in LIBs, separator is of paramount importance for safety and rate performance of LIBs. Among the various separators, composite separators have been widely investigated for improving their thermal stability, mechanical strength, electrolyte uptake, and ionic conductivity. Herein, the challenges and limitations of commercial separators for LIBs are reviewed, and a systematic overview of the state‐of‐the‐art research progress in composite separators is provided for safe and high rate LIBs. Various combination types of composite separators including blending, layer, core–shell, and grafting types are covered. In addition, models and simulations based on the various types of composite separators are discussed to comprehend the composite mechanism for robust performances. At the end, future directions and perspectives for further advances in composite separators are presented to boost safety and rate capacity of LIBs.

Monolayer protected gold nanoparticles (AuNPs) modified with a 3-aryl-3-(trifluoromethyl)diazirine functionality at its terminus (Diaz-AuNPs, 3.9 nm) were prepared and irradiated in the presence of two very different substrates, reduced graphene and glass. Upon irradiation, the terminal diazirine group loses nitrogen to generate a reactive carbene at the interface of the AuNPs that can then undergo addition or insertion reactions with functional groups on the graphene or glass surfaces, leading to the formation of graphene-AuNP and glass-AuNP hybrids, respectively. The AuNP hybrids were characterized using TEM, XRD, XPS, AFM, and UV-vis spectroscopy. Control experiments done in the absence of irradiation demonstrate that carbene activation is required for incorporation of significant AuNP onto the materials. The AuNP hybrids are robust and stable to excessive washing and centrifugation supporting the covalent nature of the interaction between the AuNP and the graphene or silicate glass substrates. Because the formation of the composite is light activated, it lends itself to photopatterning; this application is demonstrated for making the glass-AuNP composites.