Jiangsu Province Special Equipment Safety Supervision and Inspection Institute

Hydrogen leakage is a critical safety concern for high-pressure storage systems, where orifice geometry significantly influences dispersion and risk. Previous studies on leakage and diffusion have mostly focused on closed or semi-closed environments, while thorough exploration has been conducted on open and unshielded environments. This work compares three typical orifice types—circular, slit, and Y-type—through controlled experiments. Results show that circular orifices generate directional jets with steep gradients but relatively low concentrations, with a 1 mm case reaching only 0.725% at the jet core. Slit orifices exhibit more uniform diffusion; at 1 mm, concentrations ranged from 2.125% to 2.625%. Y-type orifices presented the highest hazard, with 0.5 mm leaks producing 2.9% and 1 mm cases approaching the 4% lower flammability limit within 375 s. Equilibrium times increased with orifice size, from 400–800 s for circular and slit leaks to up to 900 s for Y-type leaks, some of which failed to stabilize. Response behavior also varied: Y-type leaks achieved rapid multi-point responses (as short as 10 s), while circular and slit leaks responded more slowly away from the jet core. Overall risk ranking was circular < slit < Y-type, underscoring the urgent need for geometry-specific monitoring strategies, sensor layouts, and emergency thresholds to ensure safe hydrogen storage.

Bird's Eye View (BEV) representation learning has greatly improved target detection and tracking in complex environments and autonomous systems, thanks to a multi-view aggregation strategy that enhances spatial awareness, reduces occlusions, and ensures continuous surveillance of targets. This paper presents an Enhanced Global Context Fusion Network for multi-target multi-camera tracking (MTMC), addressing the critical challenge of spatial association across views in large-scale surveillance systems, unlike conventional approaches that directly aggregate Bird's Eye View (BEV) features, our method hierarchically refines individual BEV embedding by integrating global context, generating bootstrap features that better preserve spatial relationships and reduce information loss. In order to improve the problem of poor robustness to real-world issues that may be caused by camera malfunctions, we introduce a data augmentation strategy that replaces the input of lost camera signals with black images during training. The results of extensive experiments on the Wildtrack dataset demonstrate the state-of-the-art performance of our approach, reaching 92.0% for MODA and 94.1% for IDF1, outperforming existing techniques with only a negligible increase in computational cost. These results validate the effectiveness of our approach in terms of improved BEV feature representation and system stability, providing a reliable solution for reliable MTMC detection and tracking in complex environments.

ABSTRACT Liu Shenqu (Massa Medicata Fermentata [MMF]) is a natural fermented product of flour (and/or wheat bran) and five medicinal herbs, Prunus armeniaca , Vigna umbellata , Artemisia annua , Polygonum hydropiper , and Xanthium strumarium . Unprocessed, stir‐fried, and charred MMF has been used therapeutically in China for over a thousand years to treat conditions such as dyspepsia, abdominal distension, and diarrhea. Variations in quantities, fermentation conditions, and processing procedures across different production regions can influence the quality of MMF products, ultimately affecting their efficacy. Therefore, it is essential to establish robust qualitative and quantitative methods for the quality control of MMF. In this study, betaine, a bioactive compound, was identified via TLC, isolated using preparative TLC and analyzed using NMR spectroscopy in MMF. Ultrasonic extraction of betaine from MMF samples was optimized using orthogonal experimental design. Following aluminum oxide (OH − type) solid‐phase extraction, a simple, rapid, and accurate HPLC method was developed for the quantification of betaine, utilizing a HILIC column. Analysis of 58 commercially available MMF batches revealed that betaine concentrations in 49 batches (84.5%) ranged from 0.75 to 4.0 mg/g, whereas only 9 samples contained concentrations below 0.5 mg/g. Notably, betaine levels were significantly lower in charred products compared with unprocessed ones ( p < 0.001), suggesting that betaine may serve as a potential biomarker for the quality control of MMF.