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IEEE International Frequency Control Symposium

作者： Chao li xuwen Hu Fuyu Sun Jie liu Xiaofeng li Shougang Zhang Chinese Academy of Sciences National Time Service Center Xi’an China University of Chinese Academy of Sciences Beijing China

Most atomic physics setups require a uniform static magnetic field to define a quantization axis. The straight four-conductor assembly has been proven to be a useful structure for producing such a uniform static magnetic field. Here, we present an improved four-conductor assembly, where each conductor consists of one straight section and two curved sections. This hybrid structure arrangement offers more degrees of freedom than the conventional straight four-conductor assembly, enabling a larger uniform field region and better field spatial uniformity. The modified magnetic field generation structure can be used in many fields of atomic precision spectroscopy.

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Leather Defect Detection Algorithm Based on an Improved YOLOv5s

Leather Defect Detection Algorithm Based on an Improved YOLO...

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Pattern Recognition and Artificial Intelligence (PRAI), International Conference on

作者： xuwen He Hao li Yifan liu Rui Song Yuchen Zhao Xiao Ou School of Mathematics and Computer Science Wuhan Polytechnic University Wuhan China

ISBN: (数字)9798350350890

ISBN: (纸本)9798350350906

In the field of intelligent manufacturing, the realization of efficient and accurate automated surface defect detection is particularly critical for enhancing product quality, especially in the leather industry, which holds a significant position in global trade. Traditional defect detection methods encounter challenges in handling complex scenes and identifying minute defects. However, the advent of deep learning technologies has provided a new pathway to address these issues. This paper is dedicated to innovative research on the precise localization and detailed classification of leather surface defects through the enhancement of deep learning models, aiming to overcome the limitations of existing technologies and improve the accuracy and efficiency of detection. By extending the YOLOv5s model, this study has developed the CMR-YOLO algorithm. This algorithm integrates the Channel Attention mechanism (CA), an improved Multi-Dimensional Precision Intersection over Union (MPDIoU), and the Cross Stage Partial Residual feature enhancement module (C3R). These enhancements not only improve the classification accuracy but also bolster the model's stability and robustness in complex scenes. Through the comprehensive application of these techniques, the CMR-YOLO algorithm demonstrates improved performance in categorizing different types of leather defects, particularly effective in handling diverse defect characteristics and accurately classifying various defects. Compared to the traditional YOLOv5s, the CMR-YOLO algorithm also exhibits improved accuracy in defect classification, with the mAP50 increasing from 62.5% to 79.5%, effectively enhancing the overall performance of leather defect detection. These research outcomes not only achieve technological breakthroughs but also provide significant technical support for quality control and intelligent manufacturing in the leather goods industry.

关键词： YOLO Industries Deep learning Accuracy Attention mechanisms Prediction algorithms Robustness Classification algorithms Manufacturing Defect detection

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Influence of Femtosecond Laser Surface Modification on Tensile Properties of Titanium Alloy

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MICROMACHINES 2024年第1期15卷 152-152页

作者： Zhou, Kai Nie, Xiaoyuan Che, Xingbang Xiao, Han Wang, xuwen liao, Junming Wu, Xu Yang, Can li, Chunbo Shenzhen Technol Univ Sino German Coll Intelligent Mfg Shenzhen 518118 Peoples R China Shenzhen Technol Univ Key Lab Adv Opt Precis Mfg Technol Guangdong Higher Educ Inst Shenzhen 518118 Peoples R China

Titanium alloy components often experience damage from impact loads during usage, which makes improving the mechanical properties of TC4 titanium alloys crucial. This paper investigates the influence of laser scanning irradiation on the tensile properties of thin titanium alloy sheets. Results indicate that the tensile strength of thin titanium alloy sheets exhibits a trend of initial increase followed by a decrease. Different levels of enhancement are observed in the elongation at break of a cross-section. Optimal improvement in the elongation at break is achieved when the laser fluence is around 8 J/cm2, while the maximum increase in tensile strength occurs at approximately 10 J/cm2. Using femtosecond laser surface irradiation, this study compares the maximum enhancement in the tensile strength of titanium alloy base materials, which is approximately 8.54%, and the maximum increase in elongation at break, which reaches 25.61%. In addition, the results verify that cracks in tensile fractures of TC4 start from the middle, while laser-induced fracture cracks occur from both ends.

关键词： TC4 femtosecond laser surface modification process parameters mechanical properties

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Effect of planting salt-tolerant legumes on coastal saline soil nutrient availability and microbial communities

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JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023年第1期345卷 118574页

作者： Zheng, Yanfen Cao, xuwen Zhou, Yanan li, Zhe Yang, Yanzhe Zhao, Donglin li, Yiqiang Xu, Zongchang Zhang, Cheng-Sheng Chinese Acad Agr Sci Tobacco Res Inst Marine Agr Res Ctr Qingdao 266101 Peoples R China Shandong Univ Inst Marine Sci & Technol Qingdao 266200 Peoples R China Natl Ctr Technol Innovat Comprehens Utilizat Salin Dongying 257300 Peoples R China

Soil salinization is a serious global environmental problem affecting sustainable development of agriculture. Legumes are excellent candidates for the phytoremediation of saline soils;however, how soil microbes mediate the amelioration of coastal saline ecosystems is unknown. In this study, two salt-tolerant legumes, Glycine soja and Sesbania cannabina were planted in coastal saline soil for three years. Soil nutrient availability and microbiota structure (including bacteria, fungi, and diazotrophs) were compared between the phytoremediated soils and control soil (barren land). Planting legumes reduced soil salinity, and increased total carbon, total nitrogen, and NO3  -N contents. Among the soil microbiota, some nitrogen-fixing bacteria (e.g., Azotobacter) were enriched in legumes, which were probably responsible for soil nitrogen accumulation. The complexity of the bacterial, fungal, and diazotrophic networks increased significantly from the control to the phytoremediated soils, suggesting that the soil microbial community formed closer ecological interactions during remediation. Furthermore, the dominant microbial functions were chemoheterotrophy (24.75%) and aerobic chemoheterotrophy (21.97%) involved in the carbon cycle, followed by nitrification (13.68%) and aerobic ammonia oxidation (13.34%) involved in the nitrogen cycle. Overall, our findings suggested that G. soja and S. cannabina legumes were suitable for ameliorating saline soils as they decreased soil salinity and increased soil nutrient content, with microorganisms especially nitrogen-fixing bacteria, playing an important role in this remediation process.

关键词： Phytoremediation Saline soil Nitrogen Microbial community Salt-tolerant legume

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Optimization of the Natural Gas Hydrate Hot Water Injection Production Method: Insights from Numerical and Phase Equilibrium Analysis

SSRN

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SSRN 2023年

作者： Zhang, Zhaobin li, Yuxuan li, Shouding He, Jianming li, Xiao Xu, Tao Lu, Cheng Qin, xuwen Key Laboratory of Shale Gas and Geoengineering Institute of Geology and Geophysics Chinese Academy of Sciences Beijing100029 China Innovation Academy for Earth Science Chinese Academy of Sciences Beijing100029 China College of Earth and Planetary Sciences University of Chinese Academy of Sciences Beijing100049 China Oil and Gas Resources Survey China Geological Survey Ministry of Natural Resources Beijing100083 China Guangzhou Marine Geological Survey China Geological Survey Ministry of Natural Resources Guangzhou510075 China

The heat injection during depressurization is a crucial technique for sustaining the long-term gas production rate of natural gas hydrates. To analyze the production patterns and mechanisms of hydrate dissociation under various heat injection conditions and to further optimize heat injection strategies, this study establishes a reservoir-scale three-dimensional heterogeneous computational model using a self-developed hydrate simulator. A novel in-situ heating method utilizing bottom seawater is proposed for heat injection, and comprehensive analyses of heating power and injection rates are conducted. The results indicate that increasing heating power at a constant injection rate enhances gas production rates while reducing thermal efficiency. Simultaneously, under constant heating power, gas production rates initially increase and then decrease with increasing injection rates, revealing the presence of an optimal injection rate. This paper introduces the concepts of temperature driving force and temperature modification ratio, analyzes the mechanisms of heat injection development, and derives an optimized strategy for hot water injection through curve fitting. This research enhances our understanding of the integrated approach involving thermal stimulation and depressurization, providing significant guidance for future production endeavors. © 2023, The Authors. All rights reserved.

关键词： Curve fitting

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Cation defect engineering in LaCoO3 perovskite as the "Two birds one stone" strategy to enhanced Fenton-like reaction: Regulating Co spin state and optimizing electron transfer ability

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SEPARATION AND PURIFICATION TECHNOLOGY 2024年 337卷

作者： Fang, Zhimo Feng, xuwen Zhou, Zhou Zeng, Zepeng Xia, Yuangu li, Jihong liu, Ji Hu, Bin li, Kai Lu, Qiang North China Elect Power Univ Natl Engn Res Ctr New Energy Power Generat Beijing 102206 Peoples R China

The reactive oxygen species (ROS) triggered by peroxymonosulfate (PMS), primarily composed of radicals and nonradicals, can deeply and selectively remove pollutants in complex wastewater. However, the low efficiency of electron transfer and insufficient surface catalytic sites remain the main obstacles to the development of efficient and selective PMS activators. Herein, we constructed ABO(3) perovskite catalysts (LaCoO3) with adjustable La vacancies (V-La) densities through urea introduction. Experiment, characterization, and theoretical calculation jointly revealed that VLa could not only induce electron delocalization in Co site to enhance the Co 3d - O 2p covalency for accelerating ROS (sulfate radicals (SO4 center dot-), singlet oxygen (O-1(2)), and high valent cobalt (Co(IV) = O)) generation, but also trigger the transition of spin-polarization configuration to form Co3+ (t(2g)(5)e(g)(1)) with the intermediate spin state as new active sites for surface-bound PMS* complexes production. The nonradical-dominated and radical-assisted system containing multi-site achieved efficient PMS utilization (95.6 %), excellent decontamination activity (0.753 min(-1)), good mineralization ability (82.7 %), satisfactory acid-base resistance (working pH range 3-11), and environmental robustness for actual water treatment. This study reveals the role of cation vacancy engineering in achieving "Two birds one stone" for PMS activation at the atomic level, which will guide the rational design of Fenton-like catalysts.

关键词： Peroxymonosulfate La vacancies Spin state Delocalization Radicals and nonradicals

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Experimental Study on the Strength Characteristics of Expansive Soils Improved by the MICP Method

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GEOFLUIDS 2022年第0期2022卷

作者： Tian, xuwen Xiao, Hongbin li, Zixiang li, Zhenyu Su, Huanyu Ouyang, Qianwen Cent South Univ Forestry & Technol Sch Civil Engn Changsha 410000 Peoples R China

Microbially induced calcite precipitation (MICP) has been a promising method to improve geotechnical engineering properties;however, there are few literatures about the application of the MICP method to improve the strength characteristics of expansive soils with low permeability. In this paper, a series of CD triaxial tests were carried out to investigate the effect of the MICP method on the strength characteristics of the expansive soils. The results show that the shear strength of the specimens increased with the increase in the cementation solution and eventually reached a stable value. The MICP method can significantly improve the shear strength index of the expansive soils. The cohesion of the expansive soils was increased from 29.52 kPa to 39.41 kPa, and the internal friction angle was increased from 20.13 degrees to 29.58 degrees. The stress-strain curves of expansive soil samples improved by the MICP method show a hyperbolic relationship, which is characterized by strain hardening. The hyperbolic model was chosen to describe the stress-strain relationship of the expansive soils improved by the MICP method, and the predicted results were in good agreement with the measured results. Moreover, we performed a scanning electron microscope (SEM) experiment and revealed the mechanism of the MICP method to improve the strength characteristics of expansive soils. The conclusions above can provide a theoretical basis to further study the strength characteristics of improved expansive soils by the MICP method.

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Electrochemically lighting Up Luminophores at Similar Low Triggering Potentials with Mechanistic Insights

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ANALYTICAL CHEMISTRY 2020年第8期92卷 6144-6149页

作者： Fu, li Zhang, Bin Fu, Kena Gao, xuwen Zou, Guizheng Shandong Univ Sch Chem & Chem Engn Jinan 250100 Peoples R China

Electrochemiluminescence (ECL) with high electrode compatibility and less electrochemical interference has conventionally been envisioned by lowering the oxidative potential of luminophores and/or screening luminophores with a low oxidative potential. Herein, an alternative was developed by employing the environmental-friendly carbohydrazide as a coreactant, which enabled serial luminophores with oxidativereduction ECL at one similar low triggering potential around 0.55 V versus Ag/AgCl, including Ru(bpy)(3)(2+ )as well as CdTe, CdSe, CuInS2/ZnS, and Au nanocrystals. Because the eight-electron releasing process of carbohydrazide was electrochemically triggered at similar to 0.25 V versus Ag/AgCl, the radicals generated via electrochemical oxidation of carbohydrazide could reduce the luminophores at a much lower potential than those of traditional coreactants. All the luminophore/carbohydrazide systems exhibited one ECL process around 0.55 V, which was about 0.65 V lower than that of a traditional Ru(bpy)(3)(2+)/tri-n-propylamine system (typically around +1.2 V), and even lower than the oxidative potential of some luminophores. The ECL of the luminophore/carbohydrazide system was spectrally close to that of the corresponding luminophore/tri-n-propylamine system;the maximum emission wavelength of the low triggering potential ECL could shift from 540 to 783 nm via the selection of luminophores in this case. The coreactant screening strategy would be a favorable addition to the expected luminophore screening strategy for achieving enhanced ECL performance. This work created an avenue toward a deeper understanding of the ECL mechanism.

关键词： Electrochemically Electrochemiluminescence

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Cable External Breakage Source Localization Method Based on Improved Generalized Cross-Correlation Phase Transform with Multi-Sensor Fusion

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Energies 2025年第10期18卷 2628-2628页

作者： xuwen Wang Jiang li College of Electrical Engineering Shanghai University of Electric Power Shanghai 200090 China

In response to the need for cable outer sound source localization, this paper proposes a collaborative localization method based on an improved generalized cross-correlation phase transform (GCC-PHAT) and multi-sensor fusion. By constructing a secondary cross-shaped sensor array model, employing a phase transform weighting function to suppress environmental noise, and incorporating an adaptive environmental compensation algorithm to eliminate multipath effects, a set of spatial localization equations is established. Innovatively, a dynamic weighting factor linked to the startup threshold is introduced; the Levenberg–Marquardt optimization algorithm is then used to iteratively solve the nonlinear equations to achieve preliminary localization in a single-pile coordinate system. Finally, a dynamic weighted fusion model is constructed through DBSCAN spatial clustering to determine the final sound source position. Experimental results demonstrate that this method reduces the mean square error of time delay estimation by 94.7% in a 90 dB industrial noise environment, decreases the localization error by 65.4% in multi-obstacle scenarios, and ultimately maintains localization accuracy within 3 m over a range of 100 m. This performance is significantly superior to that of traditional TDOA and SRP-PHAT methods, offering a high-precision localization solution for underground cable protection.

关键词： cable outbreak cable marking stakes sound source localization GCC-PHAT algorithm dynamic weighting multi-sensor fusion

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Magnetic Resonance Imaging Manifestations in 13 Cases of Seminal Vesicle Tuberculosis

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INFECTION AND DRUG RESISTANCE 2023年 16卷 6871-6879页

作者： Gan, Wei Bi, Yan Fu, xuwen Wei, Jialu Qi, Min He, Jintang li, Xiang Kunming Third Peoples Hosp Yunnan Clin Med Ctr Infect Dis Dept Radiol Kunming 650041 Yunnan Peoples R China Peoples Hosp Lincang Dept Radiol Lincang 677000 Yunnan Peoples R China Kunming Third Peoples Hosp Yunnan Clin Med Ctr Infect Dis Dept Surg Kunming 650041 Yunnan Peoples R China

Objective: This study aimed to examine the radiographic manifestations of seminal vesicle tuberculosis (SVT) on magnetic resonance imaging to gain a deeper understanding of this disease. Methods: The clinical symptoms, general conditions, relevant laboratory tests and radiological data of 13 patients diagnosed with SVT were collected through bacteriological examination. A descriptive analysis was used to explore the composition ratio and rate values of the collected data. Results: All 13 cases (100.0%) showed isointense signals on T1WI and hypointense signals on T2WI in the affected seminal vesicles, with the disappearance of the multi-chambered high signal on T2WI in normal seminal vesicles. Eight cases (61.5%) showed diffusion restriction on DWI of the affected seminal vesicle and significant enhancement on the contrast scan, whereas five cases (38.5%) showed unrestricted diffusion and mild enhancement on the contrast scan. Patients with significant enhancements exhibited higher counts and neutrophil percentages than patients with mild enhancements, with statistically significant differences (Z = 2.196, P = 0.030;Z = 2.781, P = 0.003, respectively). The counts and percentage of lymphocytes, CD3(+)T cells and CD4(+)T cells were significantly lower in patients with significant enhancements than in those with mild enhancements, with statistically significant differences (Z = -2.196, P = 0.030;Z = -2.928, P = 0.002;Z = -2.928, P = 0.002;Z = -2.928, P = 0.002, respectively). Patients with significant enhancements were more likely to have active pulmonary tuberculosis than those with mild enhancements, with a statistically significant difference (P = 0.035). Conclusion: Magnetic resonance imaging reveals distinct radiographic features of SVT, and variations in imaging presentations can indicate a patient's immune status.

关键词： seminal vesicle tuberculosis magnetic resonance imaging genitourinary tuberculosis

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