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Overhead-free Noise-tolerant Federated Learning: A New Baseline

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Machine Intelligence Research 2024年第3期21卷 526-537页

作者： Shiyi Lin Deming Zhai Feilong Zhang junjun ji.ng Xianming Liu Xiangyang ji Department of Computer Science and Technology Harbin Institute of TechnologyHarbin150000China Department of Automation Tsinghua UniversityBeijing100084China

Federated learning (FL) is a promising decentralized machine learning approach that enables multiple distributed clients to train a model jointly while keeping their data private. However, in real-world scenarios, the supervised training data stored in local clients inevitably suffer from imperfect annotations, resulting in subjective, inconsistent and biased labels. These noisy labels can harm the collaborative aggregation process of FL by inducing inconsistent decision boundaries. Unfortunately, few attempts have been made towards noise-tolerant federated learning, with most of them relying on the strategy of transmitting overhead messages to assist noisy labels detection and correction, which increases the communication burden as well as privacy risks. In this paper, we propose a simple yet effective method for noise-tolerant FL based on the well-established co-training framework. Our method leverages the inherent discrepancy in the learning ability of the local and global models in FL, which can be regarded as two complementary views. By iteratively exchanging samples with their high confident predictions, the two models “teach each other” to suppress the influence of noisy labels. The proposed scheme enjoys the benefit of overhead cost-free and can serve as a robust and efficient baseline for noise-tolerant federated learning. Experimental results demonstrate that our method outperforms existing approaches, highlighting the superiority of our method.

关键词： Federated learning noise-label learning privacy-preserving machine learning edge intelligence distributed machine learning

Copper-induced formation of heterostructured Co_(3)O_(4)/CuO hollow nanospheres towards greatly enhanced lithium storage performance

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Chinese Chemical Letters 2024年第2期35卷 594-598页

作者： junjun Zhang Huiying Lu Tianhao Yao Xin ji Qingmiao Zhang Lingjie Meng jianmin Feng Hongkang Wang College of Geography & Environment Xianyang Normal UniversityXianyang 712000China State Key Lab of Electrical Insulation and Power Equipment Center of Nanomaterials for Renewable Energy (CNRE)School of Electrical EngineeringXi'an Jiaotong UniversityXi'an 710049China School of Chemistry Xi'an Key Laboratory of Sustainable Energy Material Chemistryand Instrumental Analysis CenterXi'an Jiaotong UniversityXi'an 710049China

We report a facile template-free fabrication of heterostructured Co_(3)O_(4)/CuO hollow nanospheres using pre-synthesized Co/Cu-glycerate as conformal *** introduction of copper nitrate in the solvothermal reaction system of glycerol/isopropanol/cobalt nitrate readily induces the conversion from solid Co-glycerate to hollow Co/Cu-glycerate nanospheres,and the effect of the Co/Cu atomic ratio on the structure evolution of the metal glycerates as well as their corresponding oxides were *** examined as anode materials for lithium-ion batteries,the well-defined Co_(3)O_(4)/CuO hollow nanospheres with Co/Cu molar ratio of 2.0 demonstrate excellent lithium storage performance,delivering a high reversible capacity of 930 mAh/g after 300 cycles at a current density of 0.5 A/g and a stable capacity of 650 mAh/g after 500 cycles even at a higher current density of 2.0 A/g,which are much better than their counterparts of bare CuO and Co_(3)O_(4).The enhanced lithium storage performance can be attributed to the synergistic effect of the CuO and Co_(3)O_(4)heterostructure with hollow spherical morphology,which greatly enhances the charge/electrolyte transfer and effectively buffers the volume changes upon lithiation/delithiation cycling.

关键词： Lithium-ion batteries Co/Cu-glycerate Hollow nanospheres Co_(3)O_(4)/CuO heterostructure Electrochemical properties

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一种基于谱分析的重力场统计特征建模方法

地球物理学报 2024年第7期67卷 2582-2595页

作者：黄佳喜边少锋纪兵杨军军海军工程大学电气工程学院武汉430033 中国地质大学(武汉)地质探测与评估教育部重点实验室武汉430074 中国自然资源航空物探遥感中心北京100083

重力场的统计特征主要包括协方差(相关函数)、功率谱密度、球谐阶方差等参量,是从空域、频域和球谐域描述重力场变化规律的主要依据.本文以扰动位的距离倒数协方差模型为核函数,研究了一种能在不同重力场元之间自洽解析转换的统计特征... 详细信息

重力场的统计特征主要包括协方差(相关函数)、功率谱密度、球谐阶方差等参量,是从空域、频域和球谐域描述重力场变化规律的主要依据.本文以扰动位的距离倒数协方差模型为核函数,研究了一种能在不同重力场元之间自洽解析转换的统计特征建模方法.分别利用高分辨率的地面重力异常和实测航空重力梯度数据进行功率谱分析,结合EGM2008模型构建了3组重力场统计特征模型,分析了本文模型与经典模型的差异,并用于高频重力场随机模拟,验证了本文方法在不同频率区间建模的可行性和实用性.本文模型可用于重力梯度探测、高频重力场随机模拟、重力场推估等方面的定量分析,相关算法和思路也可为构建更精细的统计特征模型提供借鉴.

关键词：功率谱密度协方差阶方差统计特征航空重力梯度距离倒数模型

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前庭神经炎视频头脉冲试验及双温试验结果分析

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中华耳科学杂志 2024年第4期22卷 553-556页

作者：郭君君李斌纪茹英唐山市眩晕诊疗康复中心唐山市人民医院神经内二科唐山063000

目的回顾性分析前庭神经炎(vestibular neuritis,VN)患者急性期视频头脉冲试验(video head impulse test,vHIT)及双温试验结果,探讨其对于VN诊断的意义及二者相关性。方法回顾性选取2019年1月至2022年10月唐山市眩晕诊疗康复中心收治的V... 详细信息

目的回顾性分析前庭神经炎(vestibular neuritis,VN)患者急性期视频头脉冲试验(video head impulse test,vHIT)及双温试验结果,探讨其对于VN诊断的意义及二者相关性。方法回顾性选取2019年1月至2022年10月唐山市眩晕诊疗康复中心收治的VN急性期患者40例,依据半规管轻瘫(cannal paralysis,CP)值患者分为A组(CP>50%)15例,B组(25%≤CP≤50%)17例,C组(CP<25%)8例,比较分析其vHIT、双温试验结果。结果水平半规管、前半规管vHIT阳性均高于后半规管,差异有统计学意义(P<0.001)。双温试验结果阳性率80.00%。A组受损侧水平半规管vHIT增益值低于B组、C组,差异均有统计学意义(P<0.05);B组受损侧水平半规管vHIT增益值低于C组,差异有统计学意义(P<0.05)。结论VN患者水平半规管、前半规管高频受损概率高于后半规管。双温试验CP值越大,相应水平半规管vHIT的增益值越低。VN超早期水平半规管可能出现低频损伤反应延迟现象,需联合vHIT共同评估半规管功能。

关键词：前庭神经炎视频头脉冲试验双温试验

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冰柜灯的防冷凝设计

中国照明电器 2024年第9期 78-81页

作者：季丰应俊俊赛尔富电子有限公司浙江宁波315000

冰柜的立杆在使用过程中由于内外温差的原因,在立杆的表面会出现冷凝现象,即外界的空气遇冷在立杆上凝结成水雾,该现象会导致立杆与玻璃门冻结,从而无法打开玻璃门,影响客户购物。冰柜灯具作为冰柜内部的一个重要组成部分,常见安装在冰... 详细信息

冰柜的立杆在使用过程中由于内外温差的原因,在立杆的表面会出现冷凝现象,即外界的空气遇冷在立杆上凝结成水雾,该现象会导致立杆与玻璃门冻结,从而无法打开玻璃门,影响客户购物。冰柜灯具作为冰柜内部的一个重要组成部分,常见安装在冰柜的立杆部位,它不仅提供了必要的照明功能,还能够在一定程度上提高冰柜的使用效率,达到节能环保的目的。本文中设计了3种防止立杆冷凝的结构,通过不同的灯具与立杆结构组合,对比在各种应用场景下的能耗高低,从而让客户选择最节能的立杆结构。

关键词：冰柜冷凝现象牛顿冷却定律余热利用聚氨酯热阻值

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高温管道热损伤共线混频非线性超声检测方法

核动力工程 2024年第1期45卷 218-224页

作者：焦敬品李智强孙俊俊万国荣李骥何存富吴斌北京工业大学北京100124 中国核动力研究设计院成都610213

面向电厂安全运行需要,开展了高温管道热损伤共线混频非线性超声检测方法研究。通过扫频实验,确定了显著混频效应的激励条件,并对4个不同热损伤程度的Super304H管材进行非线性超声检测实验。对检测信号进行双谱分析,研究和频分量的双谱... 详细信息

面向电厂安全运行需要,开展了高温管道热损伤共线混频非线性超声检测方法研究。通过扫频实验,确定了显著混频效应的激励条件,并对4个不同热损伤程度的Super304H管材进行非线性超声检测实验。对检测信号进行双谱分析,研究和频分量的双谱值在相位区间的分布,确定了热损伤引起的非线性响应在相位区间上的分布范围。结果表明,依次提取的非线性声学系数与试件的热损伤程度呈现很好的相关性,可用于管道热损伤的表征。研究工作为电厂高温管道热损伤检测提供了可行方案。

关键词：高温管道热损伤混频非线性超声检测双谱分析

Eco-geotechnics for human sustainability

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Science China(Technological Sciences) 2022年第12期65卷 2809-2845页

作者： ng Charles Wang Wai ZHAng Qi ZHOU Chao NI junjun Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China School of Transportation Southeast UniversityNanjing 211189China

As a result of climate change and increasing engineering activities, soil-related disasters such as slope failures and sandstorms have become more frequent worldwide. These disasters have caused not only loss of life, but also have led to serious economic losses as well as ecological and environmental damage. To sustain mankind, a new discipline, eco-geotechnics, has rapidly become established and developed in recent years. It integrates scientific knowledge from soil mechanics, rock mechanics,ecology, biology, and atmospheric science to develop cross-disciplinary theories and carry out experiments to tackle grand world challenges such as the effects of climate change. Through the development of eco-geotechnics, various eco-friendly technologies have been developed to mitigate sandstorms and to improve the performance of earthen structures such as embankments, slopes and landfill covers. This state-of-the-art review introduces and discusses the important advances in the field of eco-geotechnics,covering theoretical developments, laboratory testing, centrifuge modelling, field monitoring and engineering ***, the research gaps and future needs of eco-geotechnics are highlighted and discussed.

关键词： sustainability eco-geotechnics atmosphere-plant-soil interactions ecology unsaturated soil mechanics

Improved flexible Li-ion hybrid capacitors： Techniques for superior stability

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Nano Research 2017年第12期10卷 4448-4456页

作者： Shengyang Dong Hongsen Li junjun Wang Xiaogang Zhang Xiulei ji ji.ngsu Key Laboratory of Materials and Technology for Energy Conversion College of Material Science and Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Department of Chemistry Oregon State University Corvallis Oregon 97331-4003 USA

Flexible power devices play an increasingly crucial role in emerging flexible electronics. To improve the electrochemical performance of flexible power devices, novel electrode structures and new energy-storage systems should be designed. Herein, a novel flexible Li-ion hybrid capacitor （LIC） is designed based on an anode comprising Li4TisO12 nanoplate arrays coated on carbon textile （LTO/CT） and a cathode comprising a flexible N-doped graphene/carbon-nanotube composite （ngC） film. The LTO/CT anode is fabricated by directly growing Li4TisO12 nano- plates on CT with robust adhesion using a simple one-pot hydrothermal reaction. Considering the volume of a real-device flexible LIC, the ngC//LTO/CT con- figuration delivers high volumetric energy and power densities of 2 mWh·cm-3 and 185 mW·cm-3, respectively. Furthermore, the flexible LIC shows excellent flexibility and electrochemical stability, with extremely small capacity fluctuation under different bending states. This work demonstrates a scalable route to assemble flexible LICs as high-performance power devices.

关键词： flexible devices Li-ion hybrid capacitors Li4TisO^2 nanoplates graphene carbon nanotube

多层螺旋CT联合糖类抗原125、甲胎蛋白在直肠癌术前淋巴结分期中的应用价值

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肿瘤研究与临床 2024年第5期36卷 351-355页

作者：骆科纯包军军海安市中医院放射科南通226600

目的探讨多层螺旋CT联合糖类抗原125(CA125)及甲胎蛋白(AFP)在直肠癌术前淋巴结分期中的应用价值。方法回顾性病例系列研究。回顾性分析2020年8月至2022年8月海安市中医院手术后经病理检查证实的90例直肠癌患者临床资料,分析多层螺旋CT... 详细信息

目的探讨多层螺旋CT联合糖类抗原125(CA125)及甲胎蛋白(AFP)在直肠癌术前淋巴结分期中的应用价值。方法回顾性病例系列研究。回顾性分析2020年8月至2022年8月海安市中医院手术后经病理检查证实的90例直肠癌患者临床资料,分析多层螺旋CT判断术前N分期与病理N分期的诊断符合率。比较不同病理N分期(N0期、N1期、N2期)患者的血清CA125及AFP水平。以术后病理结果为金标准,采用logistic回归分析多层螺旋CT、CA125和AFP与直肠癌淋巴结转移的相关性,并构建受试者工作特征(ROC)曲线,评价多层螺旋CT联合CA125、AFP对直肠癌淋巴结转移的诊断效能。结果病理分期结果显示,N0期44例,N1期33例,N2期13例;多层螺旋CT分期结果显示,N0期49例,N1期26例,N2期15例。病理分期和多层螺旋CT分期一致的N0、N1、N2期分别为34、15、5例。病理分期N0、N1、N2期组血清CA125水平分别为(15.8±1.4)U/ml、(38.9±2.4)U/ml、(85.4±3.3)U/ml,差异有统计学意义(F=5519.47,Png/ml、(79.3±4.6)ng/ml、(168.3±5.9)ng/ml,差异有统计学意义(F=5583.80,P<0.05)。logistic回归分析显示,多层螺旋CT N分期(OR=6.231,95%CI:2.164~17.939,P=0.001)、AFP(OR=1.020,95%CI:1.002~1.039,P=0.032)是直肠癌患者淋巴结转移的独立影响因素。ROC曲线分析显示,AFP、CA125、多层螺旋CT及三者联合诊断淋巴结转移的曲线下面积分别为0.850、0.731、0.745及0.912。结论多层螺旋CT联合血清CA125、AFP在直肠癌术前淋巴结分期中具有较高的应用价值。

关键词：直肠肿瘤多层螺旋CT 糖类抗原125 甲胎蛋白淋巴结转移诊断