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To enhance the computation efficiency and accuracy of three-dimensional steady temperature field of transformer windings, we propose a new non-invasive Reduced Order Model (ROM) based on a mechanism-embedded cascade network. Initially, a snapshot matrix is formed from the Full Order Model (FOM) and then combined with Proper Orthogonal Decomposition (POD) to extract key modal features that characterize the temperature field. Subsequently, a cascade network architecture, integrating Multilayer Perceptron (MLP) and Radial Basis Function Neural Network (RBFNN), is devised to swiftly map working condition parameters to modal coefficients. Additionally, the cascade network is embedded with condition sensitivity and modal contribution mechanisms to further enhance prediction accuracy. Finally, by linearly weighting the modes with predicted modal coefficients, a rapid reconstruction of the steady temperature field in transformer windings is achieved. Validation against Fluent software simulations and experimental measurements demonstrate a close agreement, with computational errors of less than 4K and an impressive single solution time of only 0.0087 s, which is 48760 times faster compared to Fluent software.

Abstract Background Gaze is the primary way for pedestrians to obtain clues from traffic scenes before making decisions. Therefore, understanding pedestrian gaze pattern is vital for traffic safety in general and for the design of autonomous vehicles. Methods In this study, participants made road-crossing decisions in a naturalistic traffic scene, with an eye-tracker recording their gaze behaviors. We manually encoded the recorded videos with 14,898 fixations, and then analyzed the gaze pattern at three levels from general to specific: gaze towards overall scenes, gaze towards vehicles and gaze towards components of vehicles. Findings At the first level, our findings indicate that frequent fixations began to appear at the distance of 100 m and peaked around 5–30 m away from pedestrians. Transversely pedestrians mainly gazed at the two lanes adjacent to themselves. Pedestrians allocated 53% gaze duration to motor vehicles. For a specific vehicle, which is the second level, the gaze duration varied with vehicles' attributes such as distances, sizes, and types. Finally, at the third level, we discovered that pedestrians’ gaze duration on different vehicle components varied with the longitudinal distance. As vehicles approach, the main area of fixation expanded from the near side headlight to the whole front and near side, and finally shift to the near side of a vehicle. Implications The distribution of fixations in space and vehicle components before pedestrian crossing can provide fundamental information for understanding and modeling of pedestrian's road-crossing behaviors. In practice, our findings can guide the timing and position of information displays on autonomous vehicles to facilitate friendly interaction with pedestrians.

Objective In this study, we investigated the advantages of attention allocation and spatial orientation among video game players (VGPs) and non-video game players (NVGPs) and explored the performance differences between the two groups in flight simulations. Method Thirty candidates from a Chinese university were categorised as VGPs and NVGPs before participating in all tests. Results The comparison of flight performance and eye movement indicators between the two groups showed that the flight performance of VGPs was significantly better than that of NVGPs. We then found that an attention shift task and group factors predicted flight performance during take-off, while spatial orientation and tracking tasks have direct and indirect effects on cruise task performance, respectively. Eye movement indicators can directly predict flight performance to a certain extent. Conclusion We believe that the transfer effect of game experience in simulated flight tasks assisted VGPs in using top-down processing strategies in the flight process, and in better allocating cognitive resources. KEY POINTS What is already known about this topic: The advantages of attention allocation and spatial orientation among video game players (VGPs) and non-video game players (NVGPs). This difference not only caused by gaming experience, but also comes from the interaction of gaming experience and individual differences. The VGPs perform better on simulated flight mission. We speculated that gaming practice had assisted VGPs in using top-down processing strategies in the flight process, and in better allocating cognitive resources. VGPs did not depend solely on low-level cognitive abilities to finish tasks, but rather could rapidly understand the relevant situation and task in order to choose a proper attention allocation strategy, that visual search patterns must be adapted according to different situations, as opposed to reliance on a single parallel or sequence search. What this topic adds: The promotional effects of gaming experience occurred in high-level cognitive processing, but this effect was also observed in low-level ability tests. The key to promoting and maintaining excellent long-term performance are comprehensive cognitive skills, advanced cognitive skills, the establishment of mental models, and adaptive top-down processing strategies. The aviation training system design should not stop at elemental training to improve general cognitive abilities, but should be a comprehensive ability-training game in order to improve training efficiency for pilots. In order to establish a cognitive ability video game training system for pilots in the future, further exploration is needed to understand whether the transfer effect would occur in real world flight missions.

Scintillator is a critical component to detect high‐energy particles or rays, which is widely used in deep space exploration, security inspection, and nondestructive testing and medical diagnosis, such as X‐ray imaging and computed tomography (CT). However, the wider application of traditional inorganic and organic scintillators is limited by the complex operation process or poor adaptability to changeable environment, and there remains a demand to develop green and stable scintillators with high sensitivity and low detection limit. Herein, the one‐step preparation of lead‐free perovskite Cs3Cu2I5 scintillator film for high‐definition X‐ray imaging by conventional chemical vapor deposition method is reported. Cs3Cu2I5 demonstrates good stability and bright‐blue emission at 445 nm and superhigh photoluminescence quantum yield (85.14%). Importantly, upon X‐ray irradiation, the Cs3Cu2I5 perovskite film exhibits light yield (≈39 251 photons MeV−1) as high as two times of the commercially available Ce:LuAG single‐crystal scintillator (≈22 000 photons MeV−1). Furthermore, the practical demonstration for a bamboo stick and insect specimens illustrates sensitive scintillation response to X‐ray signals with superior linearity and high‐quality images in X‐ray photography and CT. Overall, Cs3Cu2I5 film provides nontoxicity, high radioluminescence intensity, and good stability, it can be regarded as a competitive material for X‐ray imaging.

Marine controlled-source electromagnetics (MCSEM) is an effective method to map the spatial distribution of gas hydrate and calculate gas hydrate saturation. An MCSEM survey is conducted in the Lingnan low uplift (LNLU), Qiongdongnan Basin (QDNB), South China Sea (SCS), and then the measured data are processed to obtain the geoelectric structure. The estimated gas hydrate stability zone (GHSZ) ranges from 0 to 320 mbsf, and shallow high-conductive sediments serving as gas hydrate caps are at depths ranging from 0 to 100 mbsf (meters below the seafloor). The 2D resistivity model reveals multiple high-resistivity bodies at depths ranging from 100 to 320 mbsf, and BSRs are at depths of 240 mbsf to 280 mbsf, indicating a transversely uneven gas hydrate reservoir in the study area. Moreover, two high-resistivity bodies are detected beneath the GHSZ, implying the presence of potential gas transport pathways. The gas hydrate saturation with a variation of 0–68.4% is calculated using the MCSEM resistivity and Archie’s law. According to the resistivity model and geological data, the transversely uneven gas hydrate reservoir may be associated with multiple gas sources, including shallow biogenic gas and deep pyrolytic gas. The shallow biogenic gas is transported to the GHSZ via short-distance migration and free diffusion, and the deep pyrolytic gas is transported to the GHSZ via two microcracks. In addition, this case emphasizes that the dynamic accumulation of gas hydrate is an important factor causing reservoir heterogeneity.

Abstract Seawater motion-induced electromagnetic (EM) noise along the seafloor has a large impact on marine magnetotelluric (MT) data quality. Although the mechanical stability of ocean bottom electromagnetic receivers (OBEMs) has improved due to buoyancy optimization, completely eliminating EM noise generated by seafloor currents as a result of instrument rocking or induction from the Earth’s magnetic field is still not possible. The velocity of the current represents the quantification of seafloor conditions. To mitigate this problem, we installed a current meter on an OBEM to measure the synchronous current velocity along with the OBEM data logger. For the marine EM surveys, we conducted two surveys composed of 42 marine EM data acquisition sites in the South China Sea. We observed a strong correlation between induced EM noise and current velocity when the speed was greater than 2 cm/s. Furthermore, we developed an adaptive correlation noise-canceling filter to reduce the induced EM noise, using the current meter data as a reference signal. The filter refined the coefficients using a least-mean-squares algorithm. We were able to reduce the induced EM noise by pre-filtering the raw time series data with an adaptive correlation noise-canceling filter and using current meter data from nearby sites. Since seafloor currents are clearly an issue that limits MT data quality, special efforts are necessary to reduce seawater motion-induced EM noise in marine MT surveys.

As a novel type of mineral resource, gas hydrate has received a considerable amount of attention worldwide. This seismic detection method can detect abnormal phenomena such as the BSR, blank zones, velocity anomalies and polarity inversion of gas hydrate and become an important method of gas hydrate detection. The occurrence area of gas hydrate in the South China Sea is usually buried deep beneath the seabed. The current method cannot meet the needs of the shape and structure detection of gas hydrate deposits. With the support of the National Key R&D Program of China, some key technologies have led to developmental breakthroughs, such as ultra-high-energy plasma sources, small-group-interval high-resolution seismic streamers, and distributed three-dimensional seismic acquisition. The seismic profile obtained north of the South China Sea shows that the stratum penetration depth reaches nearly 1000 m at a depth of 1500 m, and the vertical resolution is better than 1.5 m. This system can serve the needs of high-resolution exploration of gas hydrate resources.