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稀有金属材料与工程 2020年第4期49卷 1220-1226页

作者：陈福文徐广龙周科朝常辉周廉南京工业大学材料科学与工程学院/先进金属材料研究院江苏南京211800 南京工业大学江苏南京211800 中南大学粉末冶金国家重点实验室湖南长沙410083

采用升温热膨胀和SEM观察1K/min升温条件下组织组成为(β+球状α)的Ti-55531合金的组织演变,发现组织演变为片状α析出,片状α回溶,球状α回溶。建立了升温条件下片状析出相的生长和回溶动力学方程和球状析出相的生长和回溶动力学方程,... 详细信息

采用升温热膨胀和SEM观察1K/min升温条件下组织组成为(β+球状α)的Ti-55531合金的组织演变,发现组织演变为片状α析出,片状α回溶,球状α回溶。建立了升温条件下片状析出相的生长和回溶动力学方程和球状析出相的生长和回溶动力学方程,模拟这2种形貌α相的动力学行为,并将计算结果与实验测试结果进行比较。模拟结果发现片状α的生长和回溶受Gibbs-Thomson效应影响,Gibbs-Thomson效应降低片状α尖端的稳定性,使得片状α尖端在低于平衡温度发生回溶。片状α尖端的延长遵循体扩散和界面扩散混合机制控制的动力学,而侧面增厚由体扩散控制,片状α的溶解主要受体扩散的影响。而球状α在低温下生长受扩散速率较低的β稳定元素的体扩散控制,高温下回溶受较高扩散速度Al的体扩散控制。

关键词： Ti-55531 长大/回溶动力学 Gibbs-Thomson效应扩散

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Composite Nonconvex Low-Rank Tensor Completion With Joint Structural Regression for Traffic Sensor Networks Data Recovery

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IEEE TRANSACTIONS ON COMPUTATIONAL SOCIAL SYSTEMS 2024年第5期11卷 6882-6896页

作者： chen, Xiaobo Wang, Kaiyuan Zhao, Feng Deng, fuwen Ye, Qiaolin Shandong Technol & Business Univ Sch Comp Sci & Technol Yantai 264005 Peoples R China Nanjing Forestry Univ Coll Informat Sci & Technol Nanjing 210037 Peoples R China Nanjing Forestry Univ State Key Lab Tree Genet & Breeding Nanjing 210037 Peoples R China

Traffic sensor networks allow convenient collection of travel data that are of great significance for intelligent transportation systems (ITSs). However, the universality of missing data impedes the application of ITS and thus accurate missing data recovery is indispensable in practice. Typically, the global low-rankness and local spatiotemporal smoothness exist in underlying traffic tensor data. In light of this, this article proposes an improved low-rank tensor completion (LRTC) model by exploiting abundant structural information from incomplete tensors. Specifically, a logarithm power composite (LPC)-norm is first proposed as a nonconvex substitute of the rank function, leading to a flexible characterization of tensor multidimensional correlation. Then, a joint structural regression (JSR) model is presented to simultaneously leverage the intrinsic temporal continuity and profile similarity of traffic data. By doing so, we construct a novel nonconvex LRTC model by integrating the global low-rankness and fine-grained spatiotemporal structure that are complementary to each other. To solve the proposed model, following the optimization framework of the alternating direction method of multipliers (ADMMs), we develop an efficient iterative algorithm where each step can be solved in a closed form. Extensive experiments on four real-world traffic data are conducted to evaluate the effectiveness of the proposed approach. The results demonstrate that compared with other tensor completion methods, our model significantly improves the recovery performance.

关键词： Tensors Data models Correlation Spatiotemporal phenomena Probabilistic logic Computational modeling Accuracy Nonconvex surrogate spatial-temporal correlation tensor completion traffic sensor networks

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Stochastic Non-Autoregressive Transformer-Based Multi-Modal Pedestrian Trajectory Prediction for Intelligent Vehicles

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IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS 2024年第5期25卷 3561-3574页

作者： chen, Xiaobo Zhang, Huanjia Deng, fuwen Liang, Jun Yang, Jian Shandong Technol & Business Univ Sch Comp Sci & Technol Yantai 264005 Shandong Peoples R China Jiangsu Univ Automot Engn Res Inst Zhenjiang 212013 Jiangsu Peoples R China Nankai Univ Coll Comp Sci Tianjin Key Lab Visual Comp & Intelligent Percept Tianjin 300350 Peoples R China

Pedestrian trajectory prediction, which aims at predicting the future positions of all pedestrians in a crowd scene given their past trajectories, is the cornerstone of autonomous driving and intelligent transportation systems. Accurate prediction and fast inference are both indispensable for real-world applications. In this paper, we propose a stochastic non-autoregressive Transformer-based multi-modal trajectory prediction model to address the two challenges. Specifically, a novel graph attention module dedicated to joint learning of social and temporal interaction is proposed to explore the complex interaction among pedestrians while integrating sparse attention mechanism, pedestrian identity, and temporal order contained in the trajectory data. By doing so, the interaction across temporal and social dimensions can be simultaneously processed to extract abundant context features for prediction. Besides, to accelerate inference speed, we put forward a stochastic non-autoregressive Transformer model with multi-modal prediction capability where each future trajectory can be inferred in a parallel fashion, therefore, resulting in diverse trajectory predictions and less computational cost. Extensive experiments and ablation studies are performed to evaluate our approach. The empirical results demonstrate that the proposed model not only produces high prediction accuracy but also infers with fast speed. The code of the proposed method will be publicly available at https://***/xbchen82/SNARTF.

关键词： Pedestrian trajectory prediction graph attention non-autoregressive transformer multi-modal prediction

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Transferable driver facial expression recognition based on joint discriminative correlation alignment network with enhanced feature attention

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IET INTELLIGENT TRANSPORT SYSTEMS 2023年第12期17卷 2444-2457页

作者： chen, Xiaobo Du, Jian Deng, fuwen Zhao, Feng Shandong Technol & Business Univ Sch Comp Sci & Technol Yantai Shandong Peoples R China

Facial expression is closely related to the emotions of drivers, thus facilitating safe driving detection in advanced driving assistance system (ADAS). Recently, deep learning techniques have become prevalent for facial expression recognition. However, for driving scenarios, the facial expression recognition is mainly challenged by the problems of small sample size as well as effective feature representation. To address the above issues, this paper puts forward a transfer learning-based method for driver facial expression recognition by fully exploiting the other sources of facial expression data that may obey different distributions. Specifically, an enhanced feature attention module is firstly devised such that affluent features with multi-scales can be extracted and refined based on the spatial and channel attention mechanisms. Then, a joint correlation alignment loss is presented ensuring that the samples in the source and target domains are transformed into the shared common subspace to reduce difference of both the marginal and conditional distributions. Multiple transfer learning tasks on real-world data are carried out to evaluate the proposed method. The experimental results show that our model achieves better recognition accuracy for driver facial expression compared with several traditional and deep learning-based transfer learning algorithms.

关键词： correlation alignment driver expression recognition spatial-channel attention transfer learning

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The influence of ITSF on vibration of high voltage Line-Start permanent magnet synchronous motor

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COMPEL-THE INTERNATIONAL JOURNAL FOR COMPUTATION AND MATHEMATICS IN ELECTRICAL AND ELECTRONIC ENGINEERING 2024年第2期43卷 301-317页

作者： Yang, Guanglu chen, Si Qiao, Jianwei Liu, Yubao Tian, fuwen Yang, Cunxiang Zhengzhou Univ Light Ind Coll Elect & Informat Engn Zhengzhou Peoples R China China Tobacco Henan Ind Co Ltd Nanyang Cigarette Factory Nanyang Peoples R China Zhengzhou Univ Light Ind Coll Bldg Environm Engn Zhengzhou Peoples R China Wolong Elect Nanyang Explos Protect Grp Co Ltd Nanyang Peoples R China

PurposeThe purpose of this paper is to present the influence of inter-turn short circuit faults (ITSF) on electromagnetic vibration in high-voltage line-starting permanent magnet synchronous motor (HVLSPMSMS).Design/methodology/approachIn this paper, the ampere-conductor wave model of HVLSPMSM after ITSF is established. Second, a mathematical model of the magnetic field after ITSF is established, and the influence law of the ITSF on the air-gap magnetic field is analyzed. Further, the mathematical expression of the electromagnetic force density is established based on the Maxwell tensor method. The impact of HVLSPMSM torque ripple frequency, radial electromagnetic force spatial-temporal distribution and rotor unbalanced magnetic tension force by ITSF is revealed. Finally, the electromagnetic-mechanical coupling model of HVLSPMSM is established, and the vibration spectra of the motor with different degrees of ITSF are solved by numerical *** this study, it is found that the 2np order flux density harmonics and (2 N + 1) p order electromagnetic forces are not generated when ITSF occurs in ***/valueBy analyzing the multi-harmonics of HVLSPMSM after ITSF, this paper provides a reliable method for troubleshooting from the perspective of vibration and torque fluctuation and rotor unbalanced electromagnetic force.

关键词： HVLSPMSM ITSF Electromagnetic forces Torque ripple Vibration Fault diagnosis

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Optimization of Low-Cost Ti-35421 Titanium Alloy: Phase Transformation, Bimodal Microstructure, and Combinatorial Mechanical Properties

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MATERIALS 2019年第17期12卷 2791-2791页

作者： chen, fuwen Xu, Guanglong Cui, Yuwen Chang, Hui Nanjing Tech Univ Tech Inst Adv Mat Nanjing 210009 Jiangsu Peoples R China Nanjing Tech Univ Coll Mat Sci & Engn Nanjing 210009 Jiangsu Peoples R China Cent S Univ Sch Mat Sci & Engn Changsha 410083 Hunan Peoples R China

A sophisticated understanding of phase transformations and microstructure evolution is crucial in mechanical property optimization for the newly developed low-cost Ti-35421 (Ti-3Al-5Mo-4Cr-2Zr-1Fe wt.%) titanium alloy. The phase transformations in dual-phase Ti-35421 were studied by experiments and thermo-kinetic modeling. The phase transformation reactions and temperature ranges were determined as beta ->alpha(lamellar) [410-660 degrees C], alpha(lamellar)->beta [660-740 degrees C], alpha(lath)->beta [740-825 degrees C]. The Gibbs-Thomson effect and multicomponent diffusivities were proven to be responsible for the distinguishing behaviors of growth and dissolution between two alpha phases. The aging temperature of 540 degrees C was optimized based on calculations. It introduced a bimodal microstructure containing stubby alpha lamellae and beta matrix. The mechanical properties of bimodal Ti-35421 were tested and compared with baseline alloy Ti-B19 and other near-beta titanium alloys. The 540 degrees C aged alloy exhibits an optimal combination of mechanical properties with tensile strength of 1313 MPa, yield strength of 1240 MPa, elongation of 8.62%, and fracture toughness of 75.8 MPa.m(1/2). The bimodal Ti-35421 shows comparable performance to Ti-B19 but has lower cost in raw materials and processing. The results also demonstrate that thermo-kinetic modeling can effectively be utilized in tailoring microstructure and enhancing mechanical properties.

关键词： Ti-35421 beta alpha transformation thermo-kinetics bimodal microstructure fracture toughness

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Conservation priorities for global marine biodiversity across multiple dimensions

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National Science Review 2023年第6期10卷 108-116页

作者： Huizhong Fan Mingpan Huang Youhua chen Wenliang Zhou Yibo Hu fuwen Wei Center for Evolution and Conservation Biology Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) CAS Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Biodiversity and Ecosystem Services Chengdu Institute of Biology Chinese Academy of Sciences

Marine biodiversity plays important roles in ocean ecosystem services and has substantial economic *** diversity,genetic diversity and phylogenetic diversity,which reflect the number,evolutionary potential and evolutionary history of species in ecosystem functioning,are three important dimensions of ***-protected areas have been demonstrated as an effective area-based tool for protecting marine biodiversity,but only 2.8 % of the ocean has been fully *** is urgent to identify global conservation priority areas and percentage of the ocean across multiple dimensions of biodiversity based on Post-2020 Global Biodiversity ***,we investigate the spatial distribution of marine genetic and phylogenetic diversity using 80 075 mitochondrial DNA barcode sequences from 4316 species and a newly constructed phylogenetic tree of 8166 *** identify that the Central Indo-Pacific Ocean,Central Pacific Ocean and Western Indian Ocean harbor high levels of bio diversity across three dimensions of biodiversity,which could be designated as conservation priority *** also find that strategically protecting～22% of the ocean would allow us to reach the target of conserving～95% of currently known taxonomic,genetic and phylogenetic *** study provides insights into the spatial distribution pattern of multiple marine diversities and the findings would help to design comprehensive conservation schemes for global marine biodiversity.

关键词： marine biodiversity genetic diversity phylogenetic diversity conservation priority areas multiple dimensions

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Advances of CRISPR-Cas13 system in COVID-19 diagnosis and treatment

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Genes & Diseases 2023年第6期10卷 2414-2424页

作者： Qianqian Zhou Yanhua chen Ruolei Wang Fengjing Jia Feng He fuwen Yuan Academy of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghai 201203China

The ongoing global pandemic of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in over 570 million infections and 6 million deaths worldwide. Early detection and quarantine are essential to arrest the spread of the highly contagious COVID-19. High-risk groups, such as older adults and individuals with comorbidities, can present severe symptoms, including pyrexia, pertussis, and acute respiratory distress syndrome, on SARS-CoV-2 infection that can prove fatal, demonstrating a clear need for high-throughput and sensitive platforms to detect and eliminate SARS-CoV-2. CRISPR-Cas13, an emerging CRISPR system targeting RNA with high specificity and efficiency, has recently drawn much attention for COVID-19 diagnosis and treatment. Here, we summarized the current research progress on CRISPR-Cas13 in COVID-19 diagnosis and treatment and highlight the challenges and future research directions of CRISPR-Cas13 for effectively counteracting COVID-19.

关键词： COVID-19 CRISPR-Cas13 Diagnosis SARS-CoV-2 Treatment

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Geographical patterns and determinants of insect biodiversity in China

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Science China(Life Sciences) 2024年第6期67卷 1255-1265页

作者： Huizhong Fan Tongyi Liu Youhua chen Ziyan Liao Jun chen Yibo Hu Gexia Qiao fuwen Wei CAS Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&China-Croatia“Belt and Road”Joint Laboratory on Biodiversity and Ecosystem Services Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Jiangxi Provincial Key Laboratory of Conservation Biology College of ForestryJiangxi Agricultural UniversityNanchang 330045China University of Chinese Academy of Sciences Beijing 100049China

Insects play important roles in the maintenance of ecosystem functioning and the provision of livelihoods for millions of ***,compared with terrestrial vertebrates and angiosperms,such as the giant panda,crested ibis,and the metasequoia,insect conservation has not attracted enough attention,and a basic understanding of the geographical biodiversity patterns for major components of insects in China is ***,we investigated the geographical distribution of insect biodiversity across multiple dimensions(taxonomic,genetic,and phylogenetic diversity)based on the spatial distribution and molecular DNA sequencing data of *** analysis included 18 orders,360 families,5,275 genera,and 14,115 species of *** results revealed that Southwestern and Southeastern China harbored higher insect biodiversity and numerous older lineages,representing a museum,whereas regions located in Northwestern China harbored lower insect biodiversity and younger lineages,serving as an evolutionary *** also observed that mean annual temperature and precipitation had significantly positive effects,whereas altitude had significantly negative effects on insect biodiversity in most ***,cultivated vegetation harbored the highest insect taxonomic and phylogenetic diversity,and needleleaf and broadleaf mixed forests harbored the highest insect genetic *** results indicated that human activities may positively contribute to insect spatial diversity on a regional *** study fills a knowledge gap in insect spatial diversity in *** findings could help guide national-level conservation plans and the post-2020 biodiversity conservation framework.

关键词： insect spatial patterns multiple dimensions driving factors vegetation types

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Minimally invasive approach to managing brachiocephalic trunk cannulation complicating central venous catheterization: a case report

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INTERNATIONAL JOURNAL OF EMERGENCY MEDICINE 2024年第1期17卷 1-6页

作者： Deng, Haihui chen, Bin Peng, Deti Pang, fuwen Shenzhen Tradit Chinese Med Hosp Dept Intervent Radiol 1 Fuhua Rd Shenzhen 518033 Peoples R China Shenzhen Tradit Chinese Med Hosp Dept Liver Dis Shenzhen 518033 Peoples R China

BackgroundCentral venous catheterization, crucial for device insertion, monitoring, medication, and fluid resuscitation, commonly uses the subclavian, internal jugular, and femoral veins. Despite its general safety, complications like arterial puncture can be life-threatening, requiring rapid diagnosis and *** presentationA 74-year-old woman in the recovery phase of cerebral infarction underwent right subclavian vein catheterization. The catheter was mistakenly placed in the brachiocephalic trunk, with its tip in the ascending aorta, as confirmed by computed tomography (CT) and digital subtraction angiography (DSA). With the high surgical risk and the complexity of endovascular treatment, catheter replacement was chosen. One month after the initial placement, the catheter was replaced with a smaller one, and another month later, it was retracted without complications. Follow-up CT and DSA revealed no leakage, with the patient's vitals remaining stable. A three-month post-discharge phone follow-up confirmed the patient's continued *** case demonstrates the effective use of a catheter replacement technique as a minimally invasive repair method when other options are impractical. Ultrasound guidance is also recommended to improve the procedure's accuracy and safety.

关键词： Central venous catheterization Brachiocephalic trunk Cannulation Catheter replacement

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