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Debris Flow Susceptibility Evaluation in Meizoseismal Region:A Case Study in Jiuzhaigou,China

Journal of Earth Science 2024年第1期35卷 263-279页

作者： yongwei li linrong Xu Yonghui Shang Shuyang Chen School of Civil Engineering Central South UniversityChangsha 410075China National Engineering Research Center of High-Speed Railway Construction Technology Central South UniversityChangsha 410075China School of Civil Engineering Central South University of Forestry and TechnologyChangsha 410004China

Jiuzhaigou is situated on a mountain-canyon region and is famous for frequent tectonic activities.An abundance of loose co-seismic landslides and collapses were produced on gullies after the Jiuzhaigou Earthquake on August 8,2017,which was served as material source for debris flow in later years.Debris flow appears frequently which are seriously endangering the safety of people's lives and properties.Even the earliest debris flow appeared in areas where no case ever reported before.The debris flow susceptibility evaluation(DFSE)is used for predicting the areas prone to debris flow,which is urgently required to avoid hazards and help to guide the strategy of preventive measures.Therefore,this work employs debris flow in Jiuzhaigou to reveal the characteristics of disaster-pregnant environment and to explore the application of machine learning in DFSE.Some new viewpoints are suggested:(i)Material density factor of debris flow is first adopted in this work,and it is proved to be a critical factor for triggering debris flows by sensitivity analysis method.(ii)Deep neural network and convolutional neural network(CNN)achieve relatively good area under the curve(AUC)values and are 0.021-0.024 higher than traditional machine learning methods.(iii)Watershed units combined with CNNbased model can achieve more accurate,reliable and practical susceptibility map.This work provides an idea for prevention of debris flow in mountainous lands.

关键词： machine learning earthquakes debris flow susceptibility convolutional neural network deep neural network watershed unit

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Gypenosides ameliorate morphine-induced immunosuppression with an increased proportion of thymic T lymphocyte subsets and are involved in the regulation of the cAMP-CREM/CREB-IL-2 pathway

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Genes & Diseases 2024年第3期11卷 120-123页

作者： Hui Wang Zhonghao li Qisheng Wang Weixin lin Ziting Zhou Xinru Mu yongwei Jiang Shengfeng Lu Shaodong Chen Zhigang Lu Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor Nanjing University of Chinese MedicineNanjingJiangsu 210023China Key Laboratory of Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjingJiangsu 210023China College of Pharmacy Nanjing University of Chinese MedicineNanjingJiangsu 210023China School of Medicine Xiamen UniversityXiamenFujian 361102China

Opioid abuse can suppress the lymphatic system function,and produce severe immunosuppression that poses a significant risk of opportunistic infections such as methicillinresistant Staphylococcus aureus(MRSA)pneumonia.^(1,2)Gypenosides(Gps)are the most important immunomodulator components in the Chinese herbal medicine Gynostemma pentaphyllum.

关键词： herbal Gypenosides immunosuppression

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Cambricon-QR:a sparse and bitwise reproducible quantized training accelerator

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High Technology Letters 2024年第1期30卷 52-60页

作者：李楠 ZHAO yongwei ZHI Tian liU Chang DU Zidong HU Xing li Wei ZHANG Xishan li ling SUN Guangzhong School of Computer Science and Technology University of Science and Technology of ChinaHefei 230026P.R.China State Key Laboratory of Processors Institute of Computing TechnologyChinese Academy of SciencesBeijing 100086P.R.China Cambricon Tech.Ltd Beijing 100191P.R.China Institute of Software Chinese Academy of SciencesBeijing 100086P.R.China

Quantized training has been proven to be a prominent method to achieve deep neural network training under limited computational resources.It uses low bit-width arithmetics with a proper scaling factor to achieve negligible accuracy loss.Cambricon-Q is the ASIC design proposed to efficiently support quantized training,and achieves significant performance improvement.However,there are still two caveats in the design.First,Cambricon-Q with different hardware specifications may lead to different numerical errors,resulting in non-reproducible behaviors which may become a major concern in critical applications.Second,Cambricon-Q cannot leverage data sparsity,where considerable cycles could still be squeezed out.To address the caveats,the acceleration core of Cambricon-Q is redesigned to support fine-grained irregular data processing.The new design not only enables acceleration on sparse data,but also enables performing local dynamic quantization by contiguous value ranges(which is hardware independent),instead of contiguous addresses(which is dependent on hardware factors).Experimental results show that the accuracy loss of the method still keeps negligible,and the accelerator achieves 1.61×performance improvement over Cambricon-Q,with about 10%energy increase.

关键词： quantized training sparse accelerator Cambricon-QR

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Self-Modifying Nanointerface Driving Ultrahigh Bidirectional Thermal Conductivity Boron Nitride-Based Composite Flexible Films

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Nano-Micro Letters 2023年第1期15卷 14-24页

作者： Taoqing Huang Xinyu Zhang Tian Wang Honggang Zhang yongwei li Hua Bao Min Chen limin Wu Department of Materials Science and State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai 200433People’s Republic of China Department of Physics University of Michigan-Shanghai Jiao Tong University Joint InstituteShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Department of Chemistry Fudan UniversityShanghai 200433People’s Republic of China

While boron nitride(BN) is widely recognized as the most promising thermally conductive filler for rapidly developing high-power electronic devices due to its excellent thermal conductivity and dielectric properties,a great challenge is the poor vertical thermal conductivity when embedded in composites owing to the poor interracial interaction causing severe phonon scattering.Here,we report a novel surface modification strategy called the "self-modified nanointerface" using BN nanocrystals(BNNCs) to efficiently link the interface between BN and the polymer matrix.Combining with ice-press assembly method,an only 25 wt% BNembedded composite film can not only possess an in-plane thermal conductivity of 20.3 W m-1K-1but also,more importantly,achieve a through-plane thermal conductivity as high as 21.3 W m-1K-1,which is more than twice the reported maximum due to the ideal phonon spectrum matching between BNNCs and BN fillers,the strong interaction between the self-modified fillers and polymer matrix,as well as ladder-structured BN skeleton.The excellent thermal conductivity has been verified by theoretical calculations and the heat dissipation of a CPU.This study provides an innovative design principle to tailor composite interfaces and opens up a new path to develop high-performance composites.

关键词： Thermal management materials Boron nitride Thermal conductivity Interfacial thermal resistance

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Red Alarm for Pre-trained Models:Universal Vulnerability to Neuron-level Backdoor Attacks

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Machine Intelligence Research 2023年第2期20卷 180-193页

作者： Zhengyan Zhang Guangxuan Xiao yongwei li Tian Lv Fanchao Qi Zhiyuan liu Yasheng Wang Xin Jiang Maosong Sun Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Institute for Artificial Intelligence Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China Huawei Noah′s Ark Laboratory Hong Kong 999077China

The pre-training-then-fine-tuning paradigm has been widely used in deep learning.Due to the huge computation cost for pre-training,practitioners usually download pre-trained models from the Internet and fine-tune them on downstream datasets,while the downloaded models may suffer backdoor attacks.Different from previous attacks aiming at a target task,we show that a backdoored pre-trained model can behave maliciously in various downstream tasks without foreknowing task information.Attackers can restrict the output representations(the values of output neurons)of trigger-embedded samples to arbitrary predefined values through additional training,namely neuron-level backdoor attack(NeuBA).Since fine-tuning has little effect on model parameters,the fine-tuned model will retain the backdoor functionality and predict a specific label for the samples embedded with the same trigger.To provoke multiple labels in a specific task,attackers can introduce several triggers with predefined contrastive values.In the experiments of both natural language processing(NLP)and computer vision(CV),we show that NeuBA can well control the predictions for trigger-embedded instances with different trigger designs.Our findings sound a red alarm for the wide use of pre-trained models.Finally,we apply several defense methods to NeuBA and find that model pruning is a promising technique to resist NeuBA by omitting backdoored neurons.

关键词： Pre-trained language models backdoor attacks transformers natural language processing(NLP) computer vision(CV)

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All-SiC Fiber-Optic Sensor Based on Direct Wafer Bonding for High Temperature Pressure Sensing

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Photonic Sensors 2022年第2期12卷 130-139页

作者： Ting liANG Wangwang li Cheng LEI yongwei li Zhiqiang li Jijun XIONG Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051China Department of Physics Taiyuan Normal UniversityJinzhong 030619China Institute of Computational and Applied Physics Taiyuan Normal UniversityJinzhong 030619China

This paper presents an all-SiC fiber-optic Fabry-Perot(FP)pressure sensor based on the hydrophilic direct bonding technology for the applications in the harsh environment.The operating principle,fabrication,interface characteristics,and pressure response test of the proposed all-SiC pressure sensor are discussed.The FP cavity is formed by hermetically direct bonding of two-layer SiC wafers,including a thinned SiC diaphragm and a SiC wafer with an etched cavity.White light interference is used for the detection and demodulation of the sensor pressure signals.Experimental results demonstrate the sensing capabilities for the pressure range up to 800 kPa.The all-SiC structure without any intermediate layer can avoid the sensor failure caused by the thermal expansion coefficient mismatch and therefore has a great potential for pressure measurement in high temperature environments.

关键词： SiC pressure sensor optical-fiber high temperature direct bonding

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城际铁路曲线地段梯形轨枕有砟轨道动力性能分析

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噪声与振动控制 2024年第1期44卷 276-281页

作者：张永伟李萍李玉路周丽易科路通轨道设备有限公司北京100070 中国铁道科学研究院集团有限公司城市轨道交通中心北京100081 北京交通大学土木建筑工程学院北京100044

围绕梯形轨枕有砟轨道在城际铁路中适应性问题,测试城际列车以80~176 km/h通过半径为1432 m曲线地段时梯形轨枕有砟轨道系统动力性能指标,对比梯形轨枕有砟轨道和普通Ⅲ型枕动力性能。运用车辆与轨道动力相互作用原理和有限元方法建立... 详细信息

围绕梯形轨枕有砟轨道在城际铁路中适应性问题,测试城际列车以80~176 km/h通过半径为1432 m曲线地段时梯形轨枕有砟轨道系统动力性能指标,对比梯形轨枕有砟轨道和普通Ⅲ型枕动力性能。运用车辆与轨道动力相互作用原理和有限元方法建立曲线地段梯形轨枕有砟轨道动力学模型,进一步评估城际列车以不同速度通过时的行车安全性及舒适性。研究结果表明:(1)列车实际通过曲线地段梯形轨枕有砟轨道时的安全性和轨道结构稳定性均满足规范要求;(2)梯形轨枕有砟轨道较普通Ⅲ型枕有更良好的减振性能,车速从80提高至176 km/h时,减振效果从8.3降低至6.2 dB;(3)考虑道床横向阻力非线性特性的车辆与轨道动力相互作用分析表明,随着车速增大,梯形轨枕有砟轨道动力响应增大,列车运行安全性和舒适性均降低,但仍满足规范要求,其中车辆与轨道的横向动力响应受车速影响更为明显。

关键词：振动与波梯形轨枕有砟轨道曲线道床横向阻力动力性能

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碳点作为环保型碳钢缓蚀剂的研究进展

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材料保护 2024年第4期57卷 131-139页

作者：曹淑云李永威潍坊学院机械与自动化学院山东潍坊261061 潍坊科技学院化工与环境学院山东潍坊262700

在碳钢的酸洗工艺过程中,常需添加适量的酸洗缓蚀剂以防止钢表面造成过酸洗现象及消除酸洗过程中可能产生的氢脆问题。碳点作为一种对环境友好、廉价易得、化学稳定性好、具有潜在高缓蚀性能的“绿色”纳米材料,在腐蚀防护领域具有良好... 详细信息

在碳钢的酸洗工艺过程中,常需添加适量的酸洗缓蚀剂以防止钢表面造成过酸洗现象及消除酸洗过程中可能产生的氢脆问题。碳点作为一种对环境友好、廉价易得、化学稳定性好、具有潜在高缓蚀性能的“绿色”纳米材料,在腐蚀防护领域具有良好的应用前景。综述了国内外近年来碳点对于碳钢在酸性介质中在金属腐蚀防护领域的研究进展,对其缓蚀机理进行了探讨,对在腐蚀防护研究中存在的问题进行了简单阐述,并展望了碳点在防腐领域的发展趋势。

关键词：碳点纳米材料腐蚀缓蚀机理吸附(作用)

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革兰阴性菌外膜囊泡在感染和免疫调节中的研究进展

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中华微生物学和免疫学杂志 2024年第1期44卷 39-43页

作者：李一帆刘心伟李永伟河南中医药大学第二临床医学院郑州450046 河南省中医院检验中心河南省防治耐药菌感染中医药重点实验室郑州市病原微生物与耐药监测重点实验室郑州450002

革兰阴性菌释放的细胞外囊泡源于细胞最外层膜,被称为外膜囊泡(outer membrane vesicle,OMV),含有磷脂、脂多糖、外膜蛋白和细菌特异性抗原等细菌外膜成分。OMV在细菌生理学和致病机制中发挥重要作用,可参与生物膜形成、基因水平转移、... 详细信息

革兰阴性菌释放的细胞外囊泡源于细胞最外层膜,被称为外膜囊泡(outer membrane vesicle,OMV),含有磷脂、脂多糖、外膜蛋白和细菌特异性抗原等细菌外膜成分。OMV在细菌生理学和致病机制中发挥重要作用,可参与生物膜形成、基因水平转移、应激和炎症反应、毒素和其他生物分子的传递等,且在免疫调节以及肠道微生物群的建立和平衡中也起着重要作用。本文对OMV在细菌感染及免疫调节中的作用进行综述,为细菌导致的感染性疾病预防和治疗提供新的思路,并对OMV在肿瘤靶向治疗和新型疫苗制备中的潜在应用价值进行展望。

关键词：革兰阴性菌外膜囊泡细菌感染免疫调节

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Fructooligosaccharides enhance the therapeutic effect of xiao-zhi-fang on non-alcoholic fatty liver disease via regulating intestinal flora

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liver Research 2021年第4期5卷 217-223页

作者： Jiongshan Zhang Yue li Gemin Xiao yongwei li Heping Xie Yan Chen Department of Traditional Chinese Medicine The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina

Background:Non-alcoholic fatty liver disease(NAFLD)is a frequently occurring clinical disease,which could be treated by traditional Chinese medicine.However,the effects and mechanisms of xiao-zhi-fang(XZF)alone or in combination with fructooligosaccharides(FOS)on NAFLD remains unclear.Methods:This study established the NAFLD mouse model by feeding with a high-fat diet and by administering with XZF and/or FOS.Moreover,the fat content in the liver tissues was evaluated by oil red O and hematoxylin and eosin staining,and the liver function indices were examined using a biochemical analyzer.Changes in the intestinal flora were monitored using 16S rRNA gene sequencing.The results of the current study showed that the alanine aminotransferase,aspartate aminotransferase,total triglyc-eride,total cholesterol levels,and the amount of lipid accumulation were markedly elevated in NAFLD mice.Results:XZF alone or in combination with FOS significantly reduced lipid accumulation in the liver and blood lipid levels in NAFLD mice.Moreover,XZF alone or in combination with FOS notably altered the intestinal flora structure in NAFLD mice.Consequently,17 operational taxonomic units were decreased and nine were increased in the XZF and/or FOS groups.Conclusions:FOS may accelerate the intestinal microecological balance in NAFLD mice after treatment with XZF by promoting intestinal flora growth,thereby enhancing the therapeutic effect of XZF on NAFLD.

关键词： Fructooligosaccharides(FOS) High-fat diet(HFD) Intestinal flora Non-alcoholic fatty liver disease(NAFLD) Xiao-zhi-fang(XZF)

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