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Supervised Contrastive Learning with Term Weighting for Improving Chinese Text Classification

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Tsinghua Science and Technology 2023年第1期28卷 59-68页

作者： jiabao guo Bo Zhao Hui Liu Yifan Liu Qian Zhong School of Cyber Science and Engineering Wuhan UniversityWuhan 430000China

With the rapid growth of information retrieval technology,Chinese text classification,which is the basis of information content security,has become a widely discussed *** view of the huge difference compared with English,Chinese text task is more complex in semantic information ***,most existing Chinese text classification approaches typically regard feature representation and feature selection as the key points,but fail to take into account the learning strategy that adapts to the ***,these approaches compress the Chinese word into a representation vector,without considering the distribution of the term among the categories of *** order to improve the effect of Chinese text classification,a unified method,called Supervised Contrastive Learning with Term Weighting(SCL-TW),is proposed in this *** contrastive learning makes full use of a large amount of unlabeled data to improve model *** SCL-TW,we calculate the score of term weighting to optimize the process of data augmentation of Chinese ***,the transformed features are fed into a temporal convolution network to conduct feature *** verifications are conducted on two Chinese benchmark *** results demonstrate that SCL-TW outperforms other advanced Chinese text classification approaches by an amazing margin.

关键词： Chinese text classification Supervised Contrastive Learning(SCL) Term Weighting(TW) Temporal Convolution Network(TCN)

Effects of process parameters on the growth behavior and granule size distribution of iron ore mixtures in a novel high-shear granulator

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International Journal of Minerals,Metallurgy and Materials 2022年第12期29卷 2152-2161页

作者： Yang You jiabao guo Gang Li Zhuang Zheng Yong Li Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

This work proposes a novel horizontal high-shear granulator for iron ore granulation before sintering *** granulation behavior such as growth process and structure of granules were firstly analyzed,followed by the effects of operation conditions such as water content,initial particle size distribution,and the concentrate *** results show that the granule size increased significantly with increasing the granulation time,and the structure of granule can be divided into three types:non-nuclei,single-nuclei,and *** promotes the coalescence and growth of particles,and a better granulation performance was obtained at the water content of 8.8wt%under the current raw material *** the nuclei particle ratio led to an increase in average size of granules and permeability of the granules bed,but a decrease in growth ***,with increasing of concentrate ratio,granulation performance such as granule size,bed permeability,and uniformity became worse.

关键词： horizontal high-shear granulation iron ore granule structure granulation performance size distribution

点阵结构单元力学性能及在结构轻量化设计中的应用

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机电工程 2024年第7期41卷 1276-1284页

作者：申会鹏张天宇李行雨韩春阳郭家宝河南工业大学机电工程学院河南郑州450001 河南省超硬磨料磨削装备重点实验室河南郑州450001

针对特定功能点阵结构实现结构轻量化设计的问题,利用拓扑优化方法,构建了点阵结构单元构型。首先,从实际载荷工况特征出发,构建了初始设计模型,根据拓扑优化思想,设计出了符合力学性能特性的创新点阵结构单元谱;其次,采用有限元分析方... 详细信息

针对特定功能点阵结构实现结构轻量化设计的问题,利用拓扑优化方法,构建了点阵结构单元构型。首先,从实际载荷工况特征出发,构建了初始设计模型,根据拓扑优化思想,设计出了符合力学性能特性的创新点阵结构单元谱;其次,采用有限元分析方法,获取了点阵结构单元的力学性能,提出了以比刚度为指标的单元性能评价方法,得到了点阵结构的力学性能规律;然后,建立了典型点阵结构单元比例试件,进行了力学实验分析,通过实验数据对比,对点阵结构单元性能规律的准确性进行了验证;最后,将点阵结构性能规律应用于汽车发动机连杆的结构轻量化设计中,通过分析汽车发动机连杆的载荷特征来匹配点阵结构单元谱,填充了相应的点阵结构。研究结果表明:填充后的连杆体积减少了45%,而比刚度提高了90%,验证了点阵结构单元数据库的有效性和实用性。该点阵结构单元数据库能够为复杂零件的结构轻量化设计提供有力的科学依据。

关键词：点阵结构力学性能数值模拟实验测试轻量化设计

Recyclable Cu/g-C_(3)N_(4)nanometric semiconductor catalyzed N-formylation of amines via photocatalytic aerobic oxidative C-C bond cleavage of aldehydes under visible-light irradiation

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Chinese Chemical Letters 2023年第6期34卷 354-357页

作者： Zeyao Liang jiabao guo Peng Wang Li Zhu Xiaoquan Yao Department of Applied Chemistry School of Material Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Chemistry School of PharmacyNanjing Medical UniversityNanjing 211166China

Due to its difficulty and complexity,the cleavage and subsequent functionalization of the C(sp^(3))-C(sp^(3))single bond has received less attention than the C-C bond formation reactions that have been extensively ***,by utilizing Cu/g-C_(3)N_(4)nanometric semiconductor as a recyclable photocatalyst,an aerobic oxidative C-C bond cleavage of aldehydes was developed with the promotion of amines under visible light *** on the reaction,phenylacetaldehyde was selected as a highly efficient formylation reagent for *** blue light irradiation,good to excellent yields of formamides were achieved for various amines in 1 atm oxygen atmosphere at room *** methodology offers a practical,neutral and gentle alternative to the preparation of formamides.

关键词： Photocatalytic C-C bond cleavage N-Formylation of amines Cu/g-C_(3)N_(4) Nanometric semiconductor Visible-light

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基于力传感器的刚性转子动平衡实验方法

机电工程 2024年第7期41卷 1223-1230页

作者：申会鹏韩春阳郭家宝张天宇李行雨邱俊河南工业大学机电工程学院河南郑州450001 河南省超硬磨料磨削装备重点实验室河南郑州450001 贝尔数据科技(大连)有限公司辽宁大连116024

针对刚性转子动平衡问题,提出了一种基于拉压力传感器的综合实验平衡方法。首先,基于动平衡原理,构建了转子不平衡等效模型,求解了理论不平衡量,确保了实验的严谨性和合理性;然后,进行了结构设计、仪器与设备选择,搭建了转子动平衡实验... 详细信息

针对刚性转子动平衡问题,提出了一种基于拉压力传感器的综合实验平衡方法。首先,基于动平衡原理,构建了转子不平衡等效模型,求解了理论不平衡量,确保了实验的严谨性和合理性;然后,进行了结构设计、仪器与设备选择,搭建了转子动平衡实验平台以保障测试数据的稳定性和可重复性;最后,利用该平台,采集了力学性能数据,分析了轴系不平衡量的幅值和相位,采用了添加平衡质量的方式进行了转子动平衡实验,对基于拉压力传感器的综合实验平衡方法的可行性和有效性进行了验证。研究结果表明:平衡前左右两端不平衡质量幅值分别为2.2 kg、-3.8 kg,平衡后左右两端不平衡质量幅值分别为1.2 kg、-1.4 kg,转子系统不平衡量减小1.4 kg,平衡率为87.5%,这说明拉压力传感器和编码器相互配合以消除不平衡量的方法具有可行性。该实验平台使用拉压力传感器和编码器精确测量不平衡质量和相位,为解决旋转机械动平衡问题提供了新思路,有助于提高旋转机械的运行效率,并延长其使用寿命。

关键词：刚性转子动平衡等效模型拉压力传感器编码器转子系统不平衡量幅值和相位

Investigation on the granulation behavior of iron ore fine in a horizontal high-shear granulator

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Particuology 2022年第9期20卷 57-64页

作者： Yang You jiabao guo Gang Li Zhuang Zheng Yong Li Yaowei Yu Xuewei Lv College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced FerrometallurgySchool of Materials Science and EngineeringShanghai UniversityShanghai 200444China State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China

High-shear granulation is widely used in many particulate industries for its good capability to improve the size,strength and composition uniformity of powder *** work conducted an experimental study to investigate the granulation behavior of iron ore fine in a horizontal high-shear granulator,such as granules size distribution,granules growth rate,and permeability of the granules *** results show that the granule size and permeability of packed granules bed increase gradually with increasing the granulation time,and the growth of granules can be divided into three stages:the rapid growth stage,the slow growth stage and the relatively stable *** the higher rotational speed and larger number of impellers increase the kinetic energy and collision frequency of the particles,which causes the increase of average granule size,growth rate and permeability of granules packed *** the other hand,the shear damage effect of the impellers on the granules is also enhanced with the increase of rotational speed and impeller number,resulting in significant granule size segregation.

关键词： High shear granulation Iron ore Particle Size distribution

基于机构和机器组成原理的机构结构化正向设计方法

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机电工程 2024年第7期41卷 1135-1148页

作者：申会鹏郭家宝韩春阳李行雨张天宇王德伦河南工业大学机电工程学院河南郑州450001 河南省超硬磨料磨削装备重点实验室河南郑州450001 大连理工大学机械工程学院辽宁大连116024

针对功能需求到结构方案的创新设计问题,提出了一种基于机构和机器组成原理的机构结构化正向设计方法。首先,基于状态变换空间方法,建立了基本机构单元库,设计了机构构型与尺度,求解了机构的多样化运动方案;然后,根据运动副的约束类型... 详细信息

针对功能需求到结构方案的创新设计问题,提出了一种基于机构和机器组成原理的机构结构化正向设计方法。首先,基于状态变换空间方法,建立了基本机构单元库,设计了机构构型与尺度,求解了机构的多样化运动方案;然后,根据运动副的约束类型和性质,建立了运动副的几何约束构型,利用优化设计方法,设计了运动副结构方案;研究了复合构件的载荷、约束与结构尺度的关系模型,提出了复合构件的概念单元设计方法,设计了执行与传动机构及驱动构件;最后,遵循零件性能(强度、刚度)要求与工艺性准则,建立了机构单元结构及整机结构设计方法,并使用压力机进行了案例验证。研究结果表明:根据设计方法可得到5种一级机构、105种二级机构、735种三级机构及6种移动副方案和15种回转副方案,组合设计出的压力机方案可满足设计要求,验证了该方法的有效性,证明该机构结构化正向设计方法可为解决机构和机器创新设计问题提供新途径,缩短设计周期。

关键词：机构单元库机构构型与尺度几何约束构型机构单元概念单元设计模块化设计

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线粒体钙离子单向转运蛋白与缺血再灌注损伤

中国综合临床 2024年第5期40卷 379-384页

作者：郭佳宝马婷婷郑桓张国彬习瑾昆 063000 063000

缺血性休克、心脏骤停或切除与移植手术等会造成缺血再灌注损伤，其机制与钙离子超载密切相关。线粒体钙离子单向转运蛋白（mitochondrial calcium uniporter，MCU）是位于线粒体内膜的高选择性钙离子通道，介导钙离子进入线粒体基质，... 详细信息

缺血性休克、心脏骤停或切除与移植手术等会造成缺血再灌注损伤，其机制与钙离子超载密切相关。线粒体钙离子单向转运蛋白（mitochondrial calcium uniporter，MCU）是位于线粒体内膜的高选择性钙离子通道，介导钙离子进入线粒体基质，以其为核心的MCU复合体对维持钙离子稳态，减轻心、肾、脑、肝等器官缺血再灌注损伤起重要作用，线粒体相关内质网膜是此过程的关键蛋白。

关键词：缺血再灌注损伤线粒体钙离子单向转运蛋白钙离子

Genetically-engineered hamster models: applications and perspective in dyslipidemia and atherosclerosis-related cardiovascular disease

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Medical Review 2021年第1期1卷 92-110页

作者： George Liu Pingping Lai jiabao guo Yuhui Wang Xunde Xian Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences Ministry of EducationSchool of Basic Medical SciencesPeking University 38 Xueyuan RoadBeijing 100191China

Cardiovascular disease is the leading cause of morbidity and mortality in both developed and developing countries,in which atherosclerosis triggered by dyslipidemia is the major pathological *** the past 40 years,small rodent animals,such as mice,have been widely used for understanding of human atherosclerosis-related cardiovascular disease(ASCVD)with the advantages of low cost and ease of maintenance and ***,based on the concept of precision medicine and high demand of translational research,the applications of mouse models for human ASCVD study would be limited due to the natural differences in metabolic features between mice and humans even though they are still the most powerful tools in this research field,indicating that other species with biological similarity to humans need to be considered for studying ASCVD in *** the development and breakthrough of novel gene editing technology,Syrian golden hamster,a small rodent animal replicating the metabolic characteristics of humans,has been genetically modified,suggesting that gene-targeted hamster models will provide new insights into the precision medicine and translational research of *** purpose of this review was to summarize the genetically-modified hamster models with dyslipidemia to date,and their potential applications and perspective for ASCVD.

关键词： atherosclerosis cardiovascular disease CRISPR/Cas9 mouse Syrian golden hamster.