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There is a growing need for electricity-system flexibility to maintain real-time balance between energy supply and demand. In this paper, we explore optimal and incentive-compatible scheduling of generators for this purpose. Specifically, we examine a setting wherein each generator has a different operating cost if it is committed in advance (e.g., day- or hour-ahead) as opposed to being reserved as flexible real-time supply. We model an optimal division of generators between advanced commitment and real-time flexible reserves to minimize the expected cost of serving an uncertain demand. Next, we propose an incentive-compatible remuneration scheme with two key properties. First, the remuneration scheme incentivizes generators to reveal their true costs. Second, the scheme aligns generators’ incentives with the market operator’s optimal division of generators between advanced commitment and real-time reserve. We use a simple example to illustrate the market operator’s decision and the remuneration scheme. JEL Classification: C61, D47, D82, L94, Q4 

Abstract Compound events (CEs) are attracting increased attention due to their significant societal and ecological impacts. However, their inherent complexity can pose challenges for climate scientists and practitioners, highlighting the need for a more approachable and intuitive framework for detecting and visualising CEs. Here, we introduce the Compound Events Toolbox and Dataset (CETD), which provides the first integrated, interactive, and extensible platform for CE detection and visualisation. Employing observations, reanalysis, and model simulations, CETD can quantify the frequency, duration, and severity of multiple CE types: multivariate, sequential, and concurrent events. It can analyse CEs often linked to severe impacts on human health, wildfires, and air pollution, such as hot-dry, wet-windy, and hot-dry-stagnation events. To validate the performance of CETD, we conduct statistical analyses for several high-impact events, such as the 2019 Australian wildfires and the 2022 European heatwaves. The accessibility and extensibility of CETD will benefit the broader community by enabling them to better understand and prepare for the risks and challenges posed by CEs in a warming world. 

Abstract Integrated optomechanical systems are a leading platform for manipulating, sensing, and distributing quantum information, but are limited by residual optical heating. Here, we demonstrate a two-dimensional optomechanical crystal (OMC) geometry with increased thermal anchoring and a mechanical mode at 7.4 GHz, well aligned with the operation range of cryogenic microwave hardware and piezoelectric transducers. The eight times better thermalization than current one-dimensional OMCs, large optomechanical coupling rates,g₀/2π  ≈  880 kHz, and high optical quality factors,Q_opt = 2.4 × 10⁵, allow ground-state cooling (n_m = 0.32) of the acoustic mode from 3 K and entering the optomechanical strong-coupling regime. In pulsed sideband asymmetry measurements, we show ground-state operation (n_m < 0.45) at temperatures below 10 mK, with repetition rates up to 3 MHz, generating photon-phonon pairs at  ≈ 147 kHz. Our results extend optomechanical system capabilities and establish a robust foundation for future microwave-to-optical transducers with entanglement rates exceeding state-of-the-art superconducting qubit decoherence rates. 

A fundamental design principle of MultiPath TCP (MPTCP) congestion control algorithm (CCA) is that an MPTCP flow should be fair to and do not harm TCP flows. Unfortunately, to deal with cost heterogeneity among subflow interfaces, the existing cost-aware MPTCP CCAs often violate this design principle in an attempt to minimize the cost. Based on the network utility maximization (NUM) framework, we put forward Uni-MPTCP(⃗ω, n ), a NUM-optimal, Unified MPTCP CCA with n subflow paths and a n-dimension weight vector⃗ ω with n − 1 independent elements. Uni-MPTCP(⃗ω, n ) abides by this design principle for arbitrary⃗ω and can be customized to achieve specific cost design objectives with proper adaptation of⃗ω . As such, Uni-MPTCP(⃗ω, n ) provides a unified solution to enable cost-aware MPTCP CCAs, while adhering to the design principle. Finally, we put forward an adaptation algorithm for, ω, in Uni-MPTCP(ω, 2), aiming at maintaining a target MPTCP flow rate with minimum cost for a cost-heterogeneity case with dual connectivity. The test results based on NS-3 simulation demonstrate that Uni-MPTCP(ω, 2) can indeed effectively keep track of a given flow rate target with minimum cost, while adhering to the design principle.