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Due to the limited and fixed field of view of the onboard camera, the guiding beacons gradually drift out of sight as the AUV approaches the docking station, resulting in unreliable positioning and intermittent data. This paper proposes an underwater autonomous docking visual localization method based on a cage-type dual-layer guiding light array. To address the gradual loss of beacon visibility during AUV approach, a rationally designed localization scheme employing a cage-type, dual-layer guiding light array is presented. A dual-layer light array localization algorithm is introduced to accommodate varying beacon appearances at different docking stages by dynamically distinguishing between front and rear guiding light arrays. Following layer-wise separation of guiding lights, a robust tag-matching framework is constructed for each layer. Particle swarm optimization (PSO) is employed for high-precision initial tag matching, and a filtering strategy based on distance and angular ratio consistency eliminates unreliable matches. Under extreme conditions with three missing lights or two spurious beacons, the method achieves 90.3% and 99.6% matching success rates, respectively. After applying filtering strategy, error correction using backtracking extended Kalman filter (BTEKF) brings matching success rate to 99.9%. Simulations and underwater experiments demonstrate stable and robust tag matching across all docking phases, with average detection time of 0.112 s, even when handling dual-layer arrays. The proposed method achieves continuous visual guidance-based docking for autonomous AUV recovery.

This paper proposes a method for passive detection of autonomous underwater vehicle (AUV) wakes using a cilium-inspired wake sensor (CIWS), which can be used for the detection and tracking of AUVs. First, the characteristics of the CIWS and its working principle for detecting underwater flow fields are introduced. Then, a flow velocity sensor is used to measure the flow velocities of the “TS MINI” AUV’s wake at different positions, and a velocity field model of the “TS MINI” AUV’s wake is established. Finally, the wake field of the “TS MINI” AUV was measured at various positions using the CIWS. By analyzing the data, the characteristic frequency of the AUV’s propeller is identified, which is correlated with the AUV’s rotation speed and the number of blades. Through further analysis, a mapping model is established between the spectral amplitude of the characteristic frequency at different positions and the corresponding wake velocity. By substituting this mapping model into the AUV’s wake velocity field model, the possible position range of the sensor relative to the AUV propeller can be estimated. The research provides a technical foundation for underwater detection and tracking missions based on wake detection.

Ferromagnetic order-induced insulator-to-metal transitions via the double exchange mechanism have been studied widely. In contrast, ferromagnetic or ferrimagnetic spontaneous magnetization induced metal-to-insulator transitions (MITs), especially occurring above room temperature, remain extremely limited, although such magnetoelectric materials hold great potential for low-loss multifunctional electronic and spintronic devices. Here, a novel 3 d/ 5 d hybridized quadruple perovskite oxide, CaCu 3 Ni 2 Os 2 O 12 , was synthesized. It undergoes long-range Cu 2+ (↑)–Ni 2+ (↑)–Os 6+ (↓) ferrimagnetic order with a high Curie temperature of 393 K, maintaining a saturated magnetization of 2.15 μ B /f.u. at 300 K. Intriguingly, an MIT is found to occur concurrently at the Curie temperature. Theoretical analyses reveal that the ferrimagnetic spontaneous order significantly renormalizes the electronic band structure, which can be further modified by electronic correlation and spin–orbit coupling effects, leading to the MIT via the Lifshitz-type mechanism. This work thus provides a paradigm material to realize ferrimagnetic spontaneous magnetization induced MIT at a high critical temperature toward advanced applications. Insulator-to-metal transitions induced by spontaneous magnetization above room temperature have rarely been observed. Here, the authors show that this transition, along with concurrent high-temperature ferrimagnetic order, is realized in the novel 3d/5d hybridized quadruple perovskite oxide CaCu 3 Ni 2 Os 2 O 12 .

Ferromagnetic semiconductors with luminescent effects provide a unique platform for studying magneto-electric-optical multifunctional devices. However, little is known about such materials with spin ordering well above room temperature. By using a unique high-pressure annealing method, a Cr and Fe disordered perovskite oxide SrCr0.5Fe0.5O2.875 (SCFO) with a simple cubic structure was prepared. Magnetic measurements demonstrated the ferromagnetic behavior with a spin ordering temperature as high as 600 K. In contrast to metallic SrCrO3 and SrFeO3, SCFO, with a moderate oxygen deficiency, is a direct bandgap semiconductor with an energy gap of 2.28 eV, which is within the visible light region. As a consequence, SCFO displays a green fluorescent effect arising from the d–p bonding and anti-bonding states. Moreover, the photoluminescence intensity can be tuned by a magnetic field. This work opens up a new avenue for research on room-temperature multifunctional materials with coupled magnetic, electrical, and optical performance.Semiconductors: Maintaining magnetism at high temperatureA magnetic semiconductor that retains its magnetic properties at high temperatures has been developed by researchers in China and Germany. Semiconductor materials do much of the processing in computers and cell phones whereas magnetic materials store and retrieve information. A magnetic semiconductor merges these two functions in a single material and offers unique functionality not seen in the other materials. However, the magnetic properties of most of the known magnetic semiconductors disappear at high temperatures, limiting their application. Youwen Long from the Beijing National Laboratory for Condensed Matter Physics and colleagues used high pressures and high temperatures to create a SrCrFeO compound. This perovskite (a compound with a similar crystal structure to CaTiO3) demonstrated ferromagnetic behavior up to 600 K.

The rising frequency and severity of extreme weather events—such as floods, hurricanes, and snowstorms—pose increasing threats to the stability and reliability of modern power systems. These disruptions expose critical vulnerabilities, particularly in distribution networks, underscoring the urgent need for resilience-oriented planning and operational strategies.This thesis proposes a comprehensive, data-driven framework to enhance distribution system resilience through the strategic integration of distributed generation (DG), energy storage systems (ESS), and demand-side management. The research is organized into four major contributions:1. Data-Driven System Analysis: A scalable methodology is developed to process high-dimensional operational data from distribution networks. Using machine learning and statistical analysis, the framework identifies vulnerability patterns and operational anomalies under extreme weather conditions.2. Risk Asset Modeling: A fragility-based risk model is introduced to quantify the pre-event condition of distribution poles. By mapping impact factors of distribution poles, the model enables accurate failure probability under specific weather events.3. Preventive and Emergency Response Strategy: A novel three-stage scheduling model is formulated, extending the conventional two-stage optimization paradigm. This model integrates real-time system operation to achieve fast response from the demand side, so that reducing the negative impact of extreme weather events.4. Mobile Generation Deployment Framework: A preventive and restorative strategy is designed for rapid recovery. This involves dynamic pre-positioning and post-event allocation of mobile generators using a mixed-integer optimization model, which prioritizes critical load restoration and minimizes resilience penalties.The proposed methods are validated through simulations in MATLAB and DIgSILENT PowerFactory. The modified IEEE 33-bus test system is used to demonstrate improvements in resilience metrics. Results confirm that the framework effectively reduces system penalty costs, improves outage response, and optimizes the spatial-temporal deployment of distributed resources.

Ferromagnetic order-induced insulator-to-metal transitions via the double exchange mechanism have been studied widely. In contrast, ferromagnetic or ferrimagnetic spontaneous magnetization induced metal-to-insulator transitions (MITs), especially occurring above room temperature, remain extremely limited, although such magnetoelectric materials hold great potential for low-loss multifunctional electronic and spintronic devices. Here, a novel 3d/5d hybridized quadruple perovskite oxide, CaCu Ni Os O , was synthesized. It undergoes long-range Cu (↑)-Ni (↑)-Os (↓) ferrimagnetic order with a high Curie temperature of 393 K, maintaining a saturated magnetization of 2.15 μ /f.u. at 300 K. Intriguingly, an MIT is found to occur concurrently at the Curie temperature. Theoretical analyses reveal that the ferrimagnetic spontaneous order significantly renormalizes the electronic band structure, which can be further modified by electronic correlation and spin-orbit coupling effects, leading to the MIT via the Lifshitz-type mechanism. This work thus provides a paradigm material to realize ferrimagnetic spontaneous magnetization induced MIT at a high critical temperature toward advanced applications.

Laser induced crystal nucleation through optical tweezing, and in particular polymorph selection through laser polarization, promises unprecedented control over crystallization. However, in the absence of a nearby liquid liquid critical point or miscibility gap, the origin of the required mesoscale clusters remains unclear. A number of recent studies of so called nonclassical nucleation have suggested the presence of large amorphous clusters. Here we show that supersaturated aqueous glycine solutions form metastable intermediate particles that are off the direct path to crystal nucleation. Laser induced crystal nucleation only occurs when the laser 'activates' one of these particles. In situ low frequency Raman spectroscopy is used to demonstrate their amorphous or partially ordered character and transformation to various crystal polymorphs. The requirement for solution aging in many previously reported laser-induced crystal nucleation experiments strongly suggests that the presence of amorphous intermediates is a general requirement.

Water plays a role in the stability, reactivity, and dynamics of the solutes it contains. The presence of ions alters this capacity by changing the dynamics and structure of water. However, our understanding of how and to what extent this occurs is still incomplete. Here a study of the low-frequency Raman spectra of aqueous solutions of various cations using optical Kerr-effect spectroscopy is presented. This technique allows for the measurement of the changes that ions cause in both the diffusive dynamics and the vibrations of the hydrogen-bond structure of water. It is found that when salts are added, some of the water molecules become part of the ion solvation layers, while the rest retain the same dif-fusional properties as those of pure water. The slowing down of the dynamics of the water molecules in the solvation shell of each ion was found to depend on its charge density at infinite dilution conditions and on its position in the Hofmeister series at higher concentrations. It is also observed that all cations weaken the hydrogen bond structure of the solution and that this weakening depends only on the size of the cation. Finally, evidence is found that ions tend to form amorphous aggregates even at very dilute concentrations. This work provides a novel approach to water dynamics that can be used to better study the mechanisms of solute nucleation and crystallization, the structural stability of bio-molecules, and the dynamic properties of complex solutions such as water-in-salt electrolytes.

The origin of anomalous Hall effect (AHE) in ferromagnetic metallic glasses (MGs) is not yet understood completely. Here, the AHE is explored in Fe78Si9B13 MGs. We find the behavior of resistivity at low temperature seems to be more likely due to structure effect rather than Kondo-type effect. More importantly, we firstly find the primitive experiment anomalous Hall conductivity ({\\sigma}AH) without separation of extrinsic contribution has a linear magnetization (Mz) dependence when temperature is changing, which is another feature of intrinsic mechanism and indicates intrinsic contribution is dominated. Furthermore, the {\\sigma}AH normalized by Mz is independent of longitudinal conductivity ({\\sigma}xx), which shows the characteristic of dissipationless intrinsic mechanism. We suggest the intrinsic contribution can be understood from the density of Berry curvature integrated over occupied energies proposed for aperiodic materials recently, and the linear magnetization dependence can be understood qualitatively from the fluctuations of spin orientation and the proportional relationship between Berry curvature and magnetization. Moreover, based on the recent theory report of topological amorphous metals, we make a prediction that the large intrinsic {\\sigma}AH (616 S/cm) in Fe78Si9B13 MGs implies some topological properties of MGs waiting for further discovery.