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基于CNN-SVM和集成学习的固井质量评价方法

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吉林大学学报（理学版） 2024年第4期62卷 960-970页

作者：肖红钱祎鸣东北石油大学计算机与信息技术学院黑龙江大庆163318

为解决固井质量评价问题,提出一种基于CNN-SVM和集成学习的固井质量评价方法.首先,针对DenseNet模型采取缩减网络层数、增加多尺度卷积层、嵌入卷积注意力模块等改进措施,以提高模型的训练速度和评价准确率;其次,利用InceptionV1模块和... 详细信息

为解决固井质量评价问题,提出一种基于CNN-SVM和集成学习的固井质量评价方法.首先,针对DenseNet模型采取缩减网络层数、增加多尺度卷积层、嵌入卷积注意力模块等改进措施,以提高模型的训练速度和评价准确率;其次,利用InceptionV1模块和扩张卷积构建一个模型复杂度相对较小且评价准确率相对较高的Inception-DCNN模型;再次,优选3个经典的卷积神经网络模型(ResNet50,MobileNetV3-Small, GhostNet),利用卷积神经网络强大的特征提取能力及支持向量机的结构风险最小化能力,将上述模型分别与支持向量机组合成新的CNN-SVM模型,以提升模型的泛化能力;最后,采用Bagging方式将5个新的CNN-SVM模型集成为一个强学习器,从而提升评价结果的准确度,增强模型的抗干扰能力.实验结果表明,该方法对测试集中的3类评价样本的准确率为97.69%,与单个模型和其他方法相比提升了1~9个百分点,验证了采用基于CNN-SVM和集成学习的方法进行固井质量评价是切实可行的.

关键词：固井质量评价扇区水泥胶结测井集成学习卷积神经网络支持向量机

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基于扩散算法的无下垂分布式储能控制

上海交通大学学报 2024年第6期58卷 836-845页

作者：米阳张浩杰钱翌明邢海军龚锦霞孙改平上海电力大学电气工程学院上海200090

针对线路阻抗不匹配及母线电压不一致时,下垂控制无法同时实现母线电压稳定及储能间功率精确分配的问题,提出一种基于扩散算法的无下垂分布式储能控制策略.首先,将扩散算法应用于直流微电网的分布式估计中获取全局平均量,同时将电压额... 详细信息

针对线路阻抗不匹配及母线电压不一致时,下垂控制无法同时实现母线电压稳定及储能间功率精确分配的问题,提出一种基于扩散算法的无下垂分布式储能控制策略.首先,将扩散算法应用于直流微电网的分布式估计中获取全局平均量,同时将电压额定值与平均电压的差值作为补偿项,用于恢复母线电压偏差.为了实现不同额定容量及不同荷电状态(SOC)的储能间功率精确分配,设计储能的标准功率并将其与平均标准功率的差值作为补偿项,用于储能间SOC的均衡.最后,利用RT-LAB平台搭建模型,分别验证4种不同工作模式下所设计控制策略的有效性.实验结果表明,所提控制策略可实现孤岛直流微电网母线电压恢复及储能功率的精确分配.

关键词：直流微电网扩散算法无下垂控制分布式控制功率精确分配

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战术互联网数据采集与干扰效能评估系统设计

火力与指挥控制 2024年第6期49卷 166-176页

作者：谭志强云超蒋攀攀郑腾钱一鸣解放军63891部队河南洛阳471000

战术互联网作为陆战场上各作战单元要素之间的传输媒质,已成为陆战场的“神经系统”,通过战术互联网可实现战场信息共享和无缝连接。因此,针对战术互联网的重要作用必须加速发展针对其的对抗装备,实现信息化条件下的战场优势,为满足通... 详细信息

战术互联网作为陆战场上各作战单元要素之间的传输媒质,已成为陆战场的“神经系统”,通过战术互联网可实现战场信息共享和无缝连接。因此,针对战术互联网的重要作用必须加速发展针对其的对抗装备,实现信息化条件下的战场优势,为满足通信对抗装备作战效能评估和训练演练需求,提出了一种面向战术互联网的数据采集与干扰效果评估系统设计方案,能够对战术互联网对抗试验训练全过程实施监控分析、数据采集存贮、干扰效果评估等功能。该系统能够为通信对抗装备战技指标验证或战术互联网主要设备抗干扰训练提供有效支撑。

关键词：战术互联网通信对抗装备设计方案采集存贮效能评估

Astrocyte-Derived Saturated Lipids Mediate Cell Toxicity in the Central Nervous System

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Neuroscience Bulletin 2022年第6期38卷 699-702页

作者： yiming qian's Mengmeng Wang Jianhong Dong Yuanyuan Jiang Zhihui Huang School of Pharmacy Hangzhou Normal UniversityHangzhou 311121China Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines Engineering Laboratory of Development and Innovation Center of Traditional Chinese Medicines of Application of Traditional Chinese MedicinesCollaborative Zhejiang ProvinceHangzhou Normal UniversityHangzhou 311121China

Astrocytes,the most abundant cells in the central nervous system(CNS),have a variety of functions such as providing nutrients for neurons,facilitating the formation and functioning of synapses,pruning synapses through phagocytosis,and maintaining homeostasis[1].As a response to CNS injury and disease,quiescent astrocytes are transformed into reactive astrocytes,which usually can be divided into two types:Al and A2[2].Al astrocytes help to drive the death of neurons and oligodendrocytes in neurodegenerative disorders by producing a large number of inflammatory factors and secreted toxins,while A2 astrocytes protect neurons via releasing many neurotrophic factors[3].

关键词： homeostasis cytes releasing

血清S1P和HIF-1α水平与脓毒症患者肠屏障状况及临床预后的关系

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热带医学杂志 2024年第5期24卷 680-684,F0003页

作者：费露颍钱义明沙媛媛郭健胡冠宇上海中医药大学附属岳阳中西医结合医院急诊医学科上海200437

目的探究脓毒症患者血清1-磷酸鞘氨醇(S1P)、低氧诱导因子-1α(HIF-1α)水平变化,及与患者肠屏障状况、临床预后的关系。方法选取2021年3月-2023年3月在上海中医药大学附属岳阳中西医结合医院治疗的125例确诊的脓毒症患者为病例组,根据... 详细信息

目的探究脓毒症患者血清1-磷酸鞘氨醇(S1P)、低氧诱导因子-1α(HIF-1α)水平变化,及与患者肠屏障状况、临床预后的关系。方法选取2021年3月-2023年3月在上海中医药大学附属岳阳中西医结合医院治疗的125例确诊的脓毒症患者为病例组,根据病情分为重度组(37例)、中度组(47例)和轻度组(41例),根据预后情况分为死亡组(41例)和生存组(84例),选取同期125名体检健康者为对照组。比较血清S1P、HIF-1α水平。Logistic回归分析患者死亡的影响因素。受试者工作特征(ROC)曲线分析血清S1P、HIF-1α水平对患者死亡的预测价值。结果病例组血清S1P水平明显低于对照组,HIF-1α水平明显高于对照组,差异均有统计学意义(t=10.479、13.720,P均<0.05)。随病情发展,血清S1P依次降低,HIF-1α、二胺氧化酶(DAO)、肠脂肪酸结合蛋白(IFABP)、D-乳酸(D-LAC)水平依次升高,差异均有统计学意义(F=29.935、46.556、31.998、30.241、42.705,P均<0.05)。血清S1P水平与DAO、IFABP、D-LAC均成负相关(r=-0.589、-0.622、-0.599,P均<0.05),血清HIF-1α水平与DAO、IFABP、D-LAC均成正相关(r=0.608、0.612、0.682,P均<0.05)。死亡组HIF-1α、IL-6、高迁移率族蛋白B1(HMGB1)水平明显高于生存组,S1P水平明显低于生存组,差异均有统计学意义(t=6.016、12.273、4.040、6.922,P均<0.05)。S1P为患者死亡的独立保护因素(P<0.05),HIF-1α、IL-6、HMGB1为患者死亡的独立危险因素(P<0.05);血清S1P、HIF-1α水平预测患者死亡的曲线下面积(AUC)分别为0.839、0.824,二者联合预测的AUC为0.930,二者联合预测优于S1P、HIF-1α单独预测(Z=2.415、3.334,P=0.016、0.001)。结论脓毒症患者血清S1P水平下调,HIF-1α水平上调,且二者表达水平与肠屏障状况密切相关,二者联合预测预后具有更高的价值。

关键词：脓毒症 1-磷酸鞘氨醇低氧诱导因子-1α 肠屏障状况

Fundamental Understanding of Hydrogen Evolution Reaction on Zinc Anode Surface:A First‑Principles Study

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Nano-Micro Letters 2024年第6期16卷 180-191页

作者： Xiaoyu Liu yiming Guo Fanghua Ning Yuyu Liu Siqi Shi qian Li Jiujun Zhang Shigang Lu Jin Yi Institute for Sustainable Energy&Department of Chemistry Shanghai UniversityShanghai 200444People’s Republic of China School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China College of Materials Science and Engineering National Engineering Research Center for Magnesium AlloysChongqing UniversityChongqing 400044People’s Republic of China

Hydrogen evolution reaction(HER)has become a key factor affecting the cycling stability of aqueous Zn-ion batteries,while the corresponding fundamental issues involving HER are still unclear.Herein,the reaction mechanisms of HER on various crystalline surfaces have been investigated by first-principle calculations based on density functional theory.It is found that the Volmer step is the ratelimiting step of HER on the Zn(002)and(100)surfaces,while,the reaction rates of HER on the Zn(101),(102)and(103)surfaces are determined by the Tafel step.Moreover,the correlation between HER activity and the generalized coordination number(CN)of Zn at the surfaces has been revealed.The relatively weaker HER activity on Zn(002)surface can be attributed to the higher CN of surface Zn atom.The atomically uneven Zn(002)surface shows significantly higher HER activity than the flat Zn(002)surface as the CN of the surface Zn atom is lowered.The CN of surface Zn atom is proposed as a key descriptor of HER activity.Tuning the CN of surface Zn atom would be a vital strategy to inhibit HER on the Zn anode surface based on the presented theoretical studies.Furthermore,this work provides a theoretical basis for the in-depth understanding of HER on the Zn surface.

关键词： Aqueous Zn-ion battery Zn anode Hydrogen evolution reaction Coordination number First-principles calculation

Id2 epigenetically controls CD8^(+)T-cell exhaustion by disrupting the assembly of the Tcf3-LSD1 complex

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Cellular & Molecular Immunology 2024年第3期21卷 292-308页

作者： yiming Li Mingwei Han Haolin Wei Wan Huang Zhinan Chen Tianjiao Zhang Meirui qian Lin Jing Gang Nan Xiuxuan Sun Shuhui Dai Kun Wang Jianli Jiang Ping Zhu Liang Chen Department of Cell Biology of National Translational Science Center for Molecular Medicine and Department of Clinical Immunology of Xijing Hospital Fourth Military Medical UniversityXi’anShaanxi 710032China State Key Laboratory of New Targets Discovery and Drug Development for Major Diseases GanzhouJiangxi341000Xi’anShaanxi 710032China School of Medicine Shanghai UniversityShanghai 200444China

CD8^(+)T-cell exhaustion is a state of dysfunction that promotes tumor progression and is marked by the generation of Slamf6^(+)progenitor exhausted(Tex^(prog))and Tim-^(3+)terminally exhausted(Tex^(term))subpopulations.Inhibitor of DNA binding protein 2(Id2)has been shown to play important roles in T-cell development and CD8^(+)T-cell immunity.However,the role of Id2 in CD8^(+)T-cell exhaustion is unclear.Here,we found that Id2 transcriptionally and epigenetically regulates the generation of Texprog cells and their conversion to Texterm cells.Genetic deletion of Id2 dampens CD8^(+)T-cell-mediated immune responses and the maintenance of stem-like CD8^(+)T-cell subpopulations,suppresses PD-1 blockade and increases tumor susceptibility.Mechanistically,through its HLH domain,Id2 binds and disrupts the assembly of the Tcf3-Tal1 transcriptional regulatory complex,and thus modulates chromatin accessibility at the Slamf6 promoter by preventing the interaction of Tcf3 with the histone lysine demethylase LSD1.Therefore,Id2 increases the abundance of the permissive H3K4me2 mark on the Tcf3-occupied E-boxes in the Slamf6 promoter,modulates chromatin accessibility at the Slamf6 promoter and epigenetically regulates the generation of Slamf6+Texprog cells.An LSD1 inhibitor GSK2879552 can rescue the Id2 knockout phenotype in tumor-bearing mice.Inhibition of LSD1 increases the abundance of Slamf6^(+)Tim-3^(−)Tex^(prog) cells in tumors and the expression level of Tcf1 in Id2-deleted CD8+T cells.This study demonstrates that Id2-mediated transcriptional and epigenetic modification drives hierarchical CD8^(+)T-cell exhaustion,and the mechanistic insights gained may have implications for therapeutic intervention with tumor immune evasion.

关键词： Id2 T-cell exhaustion Epigenetic modification Immune evasion

Numerical Study on Comparison of Negative and Positive Surface Discharge in c-C_(4)F_(8)/CF_(3)I/CO_(2) Gas Mixture

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Journal of Shanghai Jiaotong university(Science) 2024年第2期29卷 202-215页

作者：范彬海周小丽钱勇臧奕茗 Academy for Engineering&Technology Fudan UniversityShanghai 200433China Department of Light Sources and Iluminating Engineering School of Information Science and TechnologyFudan UniversityShanghai 200433China Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The dynamics of negative surface discharges in c-C_(4)F_(8)/CF_(3)I/CO_(2) gas mixture is investigated here with a 2D fuid model.The distributions of ion concentration,electric field strength and photon flux during the propagation of the streamer are obtained by solving the drift-diffusion equations of particles and Poisson's equation,and the photon flux variation function during the propagation is also fitted.It is found that the streamer branches occur when the streamer transitions from the upper surface of the insulator to the side surface,and then when the streamer approaches the plane electrode,the photon flux will increase significantly.On this basis,the positive and negative surface discharge models are compared in terms of streamer characteristics,particle characteristics and streamer branches.It is found that the streamer has a higher electron concentration and electric field in the positive model.The streamer develops“floating”in the positive surface discharge,while it is close to the surface of the insulator in the negative model.In addition,the negative streamer branch has a wider width and develops further.

关键词： streamer branch surface discharge c-C_(4)F_(8)/CF_(3)I/CO_(2)gas mixture positive and negative models

考虑通信异常的直流微电网储能单元分布式协调控制研究

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电力系统保护与控制 2023年第13期51卷 50-59页

作者：米阳钱翌明张浩杰龚锦霞陈晨郭放上海电力大学电气工程学院上海200090 国网河南省电力公司经济技术研究院河南郑州450000

由于分布式新能源接入的波动性,需要针对孤岛直流微电网配置一定容量的储能设备。为了防止分布式储能单元的过度放电或深度充电,必须保证储能单元充放电过程中荷电状态(state of charge,SOC)均衡。针对该问题,提出了一种考虑通信异常的... 详细信息

由于分布式新能源接入的波动性,需要针对孤岛直流微电网配置一定容量的储能设备。为了防止分布式储能单元的过度放电或深度充电,必须保证储能单元充放电过程中荷电状态(state of charge,SOC)均衡。针对该问题,提出了一种考虑通信异常的储能单元分布式控制策略。针对不同额定容量的储能单元,对传统下垂控制进行改进,利用采样保持器周期性修改下垂系数,直至储能单元SOC均衡。并利用电压和电流信息生成单一的补偿环实现输出电流按额定容量的比例分配和直流母线电压补偿,降低系统通信能力要求。若通信发生故障,通过Dijkstra算法更新拓扑结构矩阵,基于改进后的动态一致性算法获取相邻节点的信息,得到新通信拓扑结构下的信息平均值;并通过频域分析证明系统的稳定性。最后,在RTLAB平台中搭建4种案例模型,验证所提控制策略的有效性。

关键词：分布式储能单元荷电状态下垂系数二次控制额定容量