Towards fair lights: a multi-agent masked deep reinforcement learning for efficient corridor-level traffic signal control
Peer-Reviewed Publication
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Researchers at the University of Melbourne have developed a new AI-based traffic signal control system called M2SAC that improves both fairness and efficiency at urban intersections. Unlike traditional systems focused only on cars, M2SAC accounts for pedestrians, buses, and other users. A key innovation is the phase mask mechanism, which dynamically adjusts green light timings to reduce delays. Tested on real Melbourne traffic data, the model outperformed existing methods, cutting congestion and balancing traffic flow more equitably. The approach supports smarter, fairer, and more inclusive transport systems for modern cities.
To address this challenge, researchers at Korea Advanced Institute of Science and Technology (KAIST) and Donghai Laboratory developed a new model called ProChunkFormer, which reconstructs vehicle trajectories from sparse and noisy GPS data, enabling more accurate mobility analysis and intelligent transportation planning.
The heterogeneity causes spatiotemporal inconsistencies in multimodal data, posing challenges for existing methods in multimodal feature extraction and alignment. First, in the temporal dimension, the microsecond-level temporal resolution of event data is significantly higher than the millisecond-level resolution of RGB data, resulting in temporal misalignment and making direct multimodal fusion infeasible. To address this issue, the researchers design an Event Correction Module (ECM) that temporally aligns asynchronous event streams with their corresponding image frames through optical-flow-based warping. The ECM is jointly optimized with the downstream object detection network to learn task-ware event representations.
Artificial photosynthesis is highly desired to enhance natural photosynthesis through enhanced photoelectron transfer from photocatalysts to natural photosystems. Graphitic carbon nitride (g-C3N4 or CN), a biocompatible organic polymer semiconductor, has emerged as a promising candidate for boosting natural photosynthesis, paving the way for sustainable agricultural technologies to increase crop yields.
Double transition metal nitrides and carbides (MXene) have garnered significant attention in the field of electromagnetic wave (EMW) absorption due to their distinctive structural properties. The design of efficient MXene-based EMW absorbers remains a formidable challenge in light of the high conductivity and strong van der Waals forces. In this work, we report for the first time the approach of the double-doping non-metal N and rare earth metal Ce-4f into Mo-MXene to construct Mo-MXene/MoO2-N/Ce system. This process enables partial in-situ oxidation of Mo-MXene, thereby forming a heterostructure and enhancing the interface polarization. The introduction of Ce facilitates the hybridization between the 4f orbitals of rare earth Ce and the 4d orbitals of Mo, altering the electronic structure of Ce and Mo-MXene and promoting electron migration, which contributes to polarization loss. Furthermore, incorporating melamine into the precursor can induce N doping in Mo-MXene, thereby promoting dipolar polarization. Consequently, the double-doping of N and Ce enables the synergistic effects of interface polarization, dipole polarization, and conduction loss, leading to efficient EMW absorption. Therefore, at a frequency of 13.43 GHz and a matching thickness of 4.685 mm, the optimal reflection loss (RL) value of Mo-MXene/MoO2-N/Ce reaches -57.46 dB, which exceeds a large number of reported MXene-based absorbers. This research confirms that Mo-MXene/MoO2-N/Ce is a promising EMW absorption material and provides valuable insights into modulating MXene-based EMW absorbers using rare earth elements.
A team of researchers has developed a new class of ultrafast nanomotors powered by near-infrared (NIR) light, opening new possibilities for precise nanoscale transport in water — without the need for chemical fuels.
Myocardial ischemia/reperfusion injury (MI/RI) remains a major therapeutic challenge in acute myocardial infarction due to the lack of effective treatment options. Although mesenchymal stromal cells (MSCs) and their derivatives have shown promise in cardiac repair, their clinical translation is limited by poor delivery efficiency and reduced bioactivity. In this study, researchers developed nanoscale artificial cell-derived vesicles (Rg1-ACDVs) via mechano-extrusion of MSCs preconditioned with ginsenoside Rg1, a bioactive phytochemical. Compared to conventional extracellular vesicles (Rg1-EVs) and unprimed ACDVs, Rg1-ACDVs demonstrated superior therapeutic performance by promoting cell cycle progression and facilitating DNA damage repair, as revealed by multi-omics analyses. Functional assays confirmed their dual ability to scavenge reactive oxygen species (ROS) and safeguard genomic stability in both in vitro and in vivo models. This work underscores the synergistic potential of phytochemical priming and nanoscale bioengineering, establishing Rg1-ACDVs as a scalable and effective platform for advancing MI/RI therapy toward clinical application.
The direct synthesis of semi-conductive quantum dot (QD) inks coordinated by inorganic ions in polar phases presents potential advantages such as low cost and scalability, making it an ideal approach for realizing QDs-based optoelectronic applications. However, the weak repulsive forces between QDs coordinated by inorganic ions can easily lead to agglomeration, significantly limiting size control during the synthesis process. Distinct from the traditional high-temperature injection and low-temperature growth strategy used in the synthesis of QDs with long-chain organic ligands, we discover that low-temperature injection nucleation and high-temperature growth is an effective strategy to achieve controllable tuning of reactive monomers and ligand ions in the direct synthesis system of inorganic ion-liganded QD inks, which in turn realizes the scalable, low-cost, and direct synthesis of uniform and size-tunable short-wavelength infrared (SWIR) PbS QD inks. The yield of single synthesis can be more than 10 g. Compared with the traditional ligand exchange method, the yield is improved by nearly 3 times and the cost is reduced to 7 times. Finally, the solar cell devices fabricated using these PbS SWIR QD inks achieved a photovoltaic conversion efficiency of approaching 9%, confirming the excellent optoelectronic performance of the synthesized PbS QD materials.
In photodetection systems, the ability to simultaneously measure light intensity, wavelength, and polarization is critical for advanced optical applications. A groundbreaking study introduces a novel photodetector leveraging halide perovskites, which uniquely combine electro-optic modulation with polarization-sensitive detection. By utilizing ultrafine nanoripples and micron-sized crystals in perovskite materials, this device achieves precise polarization response and electro-optic modulation. These properties, enhanced by the material’s superior optoelectronic performance, enable multidimensional polarization current generation and visualization key advancements for integrated optical systems. The innovation holds promise for applications in machine learning-driven optical technologies and compact photonic devices, marking a significant step toward multifunctional, high-efficiency optoelectronics.
The bad taste of the drug will seriously affect the patient 's medication compliance, after the mesoporous molecular sieve is loaded with the drug, it enters the channel, the amount of drug in contact with the taste buds was significantly reduced, and reduce the release rate of the drug, so that the bitterness is greatly reduced. In this paper, MCM-41 molecular sieve (MCM-41), MCM-48 molecular sieve (MCM-48)and hollow mesoporous molecular sieve (HMSS) molecular sieves were used as carriers to mask cetirizine for the first time, at the same time, it was compared with aspartame and β-cyclodextrin commonly used taste masking agents, and the drug-loaded complexes were characterized and analyzed by X-ray diffraction and Fourier Transform infrared spectroscopy, the results showed that except aspartame was only physically mixed, the other four materials were successfully adsorbed or included in the drug; among them, HMSS has a drug loading of up to 50 %, and the bitter taste of the drug is not obvious after drug loading. Its taste masking effect is obviously better than other materials, and it is expected to become a new type of high-efficiency taste masking agent.