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结合区域引导和双注意力机制的高光谱目标检测判别式学习网络

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电子学报 2024年第5期52卷 1716-1729页

作者：钟佳平李云松谢卫莹雷杰 Paolo Gamba 西安电子科技大学综合业务网全国重点实验室陕西西安710071 帕维亚大学意大利帕维亚27100

高光谱图像(HyperSpectral Images,HSIs)具有高光谱分辨率和丰富的光谱信息,其具有的大量窄波段电磁波有利于获取感兴趣目标的理化信息,并根据对应的光谱特征对不同物质进行有效区分,从而完成目标检测任务.然而有限样本、少量先验信息... 详细信息

高光谱图像(HyperSpectral Images,HSIs)具有高光谱分辨率和丰富的光谱信息,其具有的大量窄波段电磁波有利于获取感兴趣目标的理化信息,并根据对应的光谱特征对不同物质进行有效区分,从而完成目标检测任务.然而有限样本、少量先验信息、高维相似背景及不同类别差异小所导致的目标和背景混淆问题使得高光谱目标检测(Hyperspectral Target Detection,HTD)面临挑战.为此,本文提出结合区域引导和双注意力机制的高光谱目标检测判别式学习网络(Region-guided and dual-Attention Discriminative learning Network,RADN),以缓解标记样本少的条件下不同类别相似度高和相同类别差异性大导致的背景和目标不易区分的问题,减少高维冗余特征带来的计算复杂度,同时提升检测精度.本文使用经验性区域引导网络训练,采用光谱约束的无监督聚类方法确定网络输入,选择性地关注高光谱图像中的显著性特征和感兴趣区域.此外,本文在网络中添加双通道注意力机制来辅助复杂背景分布的估计,并在网络中引入不同类别光谱先验损失函数,进一步减少高维复杂背景以及光谱变化对于目标的干扰.实验结果和分析表明,RADN在不同数据集上的性能优于现有先进的算法.

关键词：高光谱目标检测无监督聚类通道注意力机制感兴趣区域光谱分辨率

基于车轮-桥面相干激励的大跨连续梁桥振动响应

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吉林大学学报（工学版） 2024年第2期54卷 436-444页

作者：韩智强谢刚卓亚娟骆佐龙李华腾太原科技大学车辆与交通工程学院太原030024 太原科技大学先进控制与装备智能化山西省重点实验室太原030024 山西大学电力与建筑学院太原030024

为获取桥面相干激励下大跨连续梁桥动力响应规律,基于虚功原理,建立五轴重载车辆动力学模型,采用模态叠加法建立桥梁动力方程,通过谐波叠加法建立桥面相干激励模型,根据轮-桥间几何和力学耦合关系,组建车轮-桥面相干激励模型,采用Matla... 详细信息

为获取桥面相干激励下大跨连续梁桥动力响应规律,基于虚功原理,建立五轴重载车辆动力学模型,采用模态叠加法建立桥梁动力方程,通过谐波叠加法建立桥面相干激励模型,根据轮-桥间几何和力学耦合关系,组建车轮-桥面相干激励模型,采用Matlab软件编译大跨连续梁桥车桥耦合振动分析系统,并开展不同等级的相干桥面激励模型对大跨连续梁桥动力响应影响研究。结果表明:当未考虑桥面不平顺影响时,桥梁冲击系数均小于规范取值,但随着桥面状况的恶化,结构典型截面的动力响应增长较快,且完全相干模型对桥梁动力响应的影响均大于部分相干激励模型,均超过规范值,其中挠度幅值最大偏差约为7.7%,弯矩幅值最大偏差约为20%,挠度冲击系数相对误差为4%~34%,弯矩冲击系数相对误差为2%~43%;随着车速的增大,桥梁冲击系数呈先增大后减小变化。最后,给出了大跨连续梁桥挠度和弯矩冲击系数包络图。相关研究成果可为连续梁桥的结构动力响应的分析与研究提供参考。

关键词：桥梁工程桥面相干激励模型车桥耦合动力响应冲击系数

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Mesoporous NiCo_2O_4 nanoneedles@MnO_2 nanoparticles grown on nickel foam for electrode used in high-performance supercapacitors

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Journal of Energy Chemistry 2019年第4期28卷 167-177页

作者： Yanmei li Jingjing Pan Jinzhu Wu Tingfeng yi ying xie School of Chemistry and Chemical Engineering Anhui University of Technology School of Resources and Materials Northeastern University at Qinhuangdao Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Science Heilongjiang University

Mesoporous NiCo_2O_4@MnO_2 nanoneedle arrays as electrode materials for supercapacitor grown on a conductive nickel foam were prepared by a facile hydrothermal route. The interconnected mesoporous structure of the NiCo_2O_4 nanoneedle arrays provides a large specific surface area for charge *** electrochemically active MnO_2 nanoparticles covered on the surface of NiCo_2O_4 nanoneedle result in a favorable synergistic storage effect because of charge redistribution at the NiCo_2O_4|MnO_2 interface,which reduces the interfacial polarization and facilitates ion diffusion. The initial specific capacitance of NiCo_2O_4@MnO_2(S2) is 1001 F g^(-1) at current density of 15 A g^(-1). The capacity retention of S2 is about87.4% after 4000 cycles, and the specific capacitance of S2 electrode only decreases from 1001 F g^(-1) to736 F g^(-1) even after 10,000 cycles. The first-principles calculations show that a chemical bonding between the NiCo_2O_4 and MnO_2 is not only helpful for stabilizing the composites but also leads to a charge redistribution at the interface, which may lead to a smaller interfacial polarization and thus beneficial for the interfacial capacity. The excellent electrochemical performance of NiCo_2O_4@MnO_2 composites(S2)can be ascribed to the high surface area, unique architecture, MnO_2 nanoparticle modification, reduced charge transfer resistance and stable interface between NiCo_2O_4 and MnO_2. The simple material synthesis and architectural design strategy provides new insights in opportunities to exhibit promising potential for practical application in energy storage.

关键词： Supercapacitor First-principles calculations Electrochemical performance Synergistic effect NiCo2O4

芽胞杆菌及其代谢物抑制包膜病毒感染的研究进展

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微生物学杂志 2024年第2期44卷 97-108页

作者：姚俞洁孟广勋韩颖颖李娟上海理工大学健康科学与工程学院上海200093 中国科学院上海巴斯德研究所微生物、发育与健康研究中心中国科学院分子病毒与免疫重点实验室中国科学院大学上海200031 中科南京生命健康高等研究院江苏南京211135

包膜病毒指具有一层脂质双层膜的病毒,如流感病毒、冠状病毒等,这些包膜病毒每年在世界范围内导致许多严重的疾病,严重威胁人类健康。使用抗病毒药物是预防与治疗病毒感染的主要策略,芽胞杆菌(Bacillus)及其代谢物能够抑制多种包膜病毒... 详细信息

包膜病毒指具有一层脂质双层膜的病毒,如流感病毒、冠状病毒等,这些包膜病毒每年在世界范围内导致许多严重的疾病,严重威胁人类健康。使用抗病毒药物是预防与治疗病毒感染的主要策略,芽胞杆菌(Bacillus)及其代谢物能够抑制多种包膜病毒的感染。本文综述了芽胞杆菌代谢的粗提物、肽、酶、胞外聚合物、小双链RNA和热灭活的枯草芽胞杆菌孢子在抗包膜病毒感染中发挥的重要作用,其机制是通过直接破坏病毒包膜、阻止膜融合、与病毒基因组RNA直接配对、催化裂解病毒RNA、激活天然免疫反应等对抗病毒,期望为包膜病毒的持续预防和治疗提供参考。

关键词：包膜病毒芽胞杆菌代谢产物病毒感染抗病毒机制

Analysis of alkaline phosphatase and γ-glutamyltransferase after radiofrequency ablation of primary liver cancer: A retrospective study

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World Journal of Gastrointestinal Surgery 2024年第9期16卷 2860-2869页

作者： Wen-Yu Huang Sheng Zheng Dan Zhu ying-Lang Zeng juan Yang Xue-li Zeng Pei liu Shun-ling Zhang Ming Yuan Zhi-Xia Wang Department of Tumor and Vascular Interventional Therapy Xiamen Humanity HospitalXiamen 361000Fujian ProvinceChina Department of Gastroenterology The Third People's Hospital of Yunnan ProvinceKunming 650011Yunnan ProvinceChina Medical Imaging Center Qian Wei Hospital of Jilin ProvinceChangchun 130000Jilin ProvinceChina Department of Science and Education The Third People's Hospital of Yunnan ProvinceKunming 650011Yunnan ProvinceChina Graduate School of Clinical Medicine Dali UniversityDali 671000Yunnan ProvinceChina Department of Hepatobiliary Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Department of Oncology The Affiliated Shuyang Hospital of Xuzhou Medical UniversitySuqian 223600Jiangsu ProvinceChina

BACKGROUND Changes in alkaline phosphatase(ALP)andγ-glutamyltransferase(GGT)levels in patients with primary liver cancer(PLC)after radiofrequency ablation(RFA).Hepatocellular carcinoma is a malignant tumor with high incidence *** a common local treatment,RFA has attracted much attention for its efficacy and influence on liver *** To investigate the effect of serum ALP and GGT levels on the prognosis of patients with PLC treated by *** The preoperative clinical data of 165 patients who were pathologically or clinically diagnosed with PLC and who received RFA in our hospital between October 2018 and June 2023 were *** chi-square test was used to compare the data between *** Kaplan-Meier method and Cox regression were used to analyze the associ-ations between serum ALP and GGT levels and overall survival,progression-free survival(PFS)and clinical characteristics of patients before *** The 1-year survival rates of patients with normal(≤135 U/L)and abnormal(>135 U/L)serum ALP before treatment were 91%and 79%,respectively;the 2-year survival rates were 90%and 68%,respectively;and the 5-year survival rates were 35%and 18%,*** difference between the two groups was statistically significant(P=0.01).Before treatment,the 1-year survival rates of patients with normal serum GGT levels(≤45 U/L)and abnormal serum GGT levels(>45 U/L)were 95%and 87%,the 2-year survival rates were 85%and 71%,and the 5-year survival rates were 37%and 21%,*** difference between the two groups was statist-ically significant(P<0.001).Serum ALP[hazard ratio(HR)=1.766,95%confidence interval(95%CI):1.068-2.921,P=0.027]and GGT(HR=2.312,95%CI:1.367-3.912,P=0.002)is closely related to the overall survival of PLC patients after RF ablation and is an independent prognostic *** 1-year PFS rates were 72%and 50%,the 2-year PFS rates were 52%and 21%,and the 5-year PFS rates were 14%and 3%,*** difference between the

关键词： Alkaline phosphatase γ-glutamyltransferase Radiofrequency ablation Primary liver cancer Retrospective study

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螺环基闭合环状结构化合物的研究进展

科学通报 2024年第4期69卷 510-530页

作者：魏颖包秋景张峥李昊马述威汪涛解令海南京邮电大学有机电子与信息显示国家重点实验室南京210023

螺环基闭合环状结构化合物是一类以螺环芳烃作为构筑单元形成的闭合环状结构的化合物,主要包括大环、共价有机框架(COF)、金属有机框架(MOF)等.此类化合物拥有规整的环状结构、可调的尺寸和形状、丰富的空间构象及光学活性等特点,在传... 详细信息

螺环基闭合环状结构化合物是一类以螺环芳烃作为构筑单元形成的闭合环状结构的化合物,主要包括大环、共价有机框架(COF)、金属有机框架(MOF)等.此类化合物拥有规整的环状结构、可调的尺寸和形状、丰富的空间构象及光学活性等特点,在传感、药物输送、吸附、分离、光学器件、分子识别等领域有着广泛的应用.根据它们空间维度的不同,可以分为零、一、二、三维螺环基闭合环状结构化合物.本文综述了近年来螺环基闭合环状结构化合物的研究进展,重点介绍了这类化合物的结构特性、合成方法、性能表征以及应用,将为化学、材料科学、生命科学、有机光电子等领域设计和制备具有更多功能的新材料提供强有力的支持.

关键词：螺环芳烃大环共价有机框架金属有机框架

Multiple Failure Modes of Compressor Station Incorporated into Risk Evaluation of Electricity-gas Integrated Energy Systems

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1439-1448页

作者： yi Tang Yuan Zhao Wenyuan li Kaigui xie juan Yu the State Key Laboratory of Power Transmission Equipment and System Security and New Technology Chongqing UniversityChongqing 400044 China

Multiple failure modes of gas compressor stations have not been modeled into risk evaluation of electricity-gas integrated energy system(EGIES).This paper presents a method to incorporate multiple failure modes of compressor stations with bypass systems in the EGIES risk *** outage models representing multi-states and multi-failure-modes of com-pressor stations and a bi-level Monte Carlo sampling algorithm for the models are developed.A novel network model of EGIES considering compressor stations with multiple failure modes is *** EGIES with a modified RBTS and an 11-node gas system is used to demonstrate the effectiveness of the proposed method and *** indicate that compressor stations have both positive and negative significant impacts on the risk of *** systems for compressor stations can effectively offset the negative *** compressor stations and their station failures in the risk evaluation of EGIES may result in an inaccurate estimation of the system risk levels and even lead to a misleading conclusion in system *** Terms-Compressor station,electricity-gas integrated energy system,multiple failure modes,risk evaluation.

关键词： Compressor station electricity-gas integrated energy system multiple failure modes risk evaluation.

Reference values of carotid intima-media thickness and arterial stiffness in Chinese adults based on ultrasound radio frequency signal: A nationwide, multicenter study

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中华医学杂志(英文版) 2024年第15期137卷 1802-1810页

作者： Xing Changyang xie Xiujing Wu Yu Xu Lei Guan Xiangping li Fan Zhan Xiaojun Yang Hengli li Jinsong Zhou Qi Mu Yuming Zhou Qing Ding Yunchuan Wang yingli Wang Xiangzhu Zheng Yu Sun Xiaofeng li Hua Zhang Chaoxue Zhao Cheng Qiu Shaodong Yan Guozhen Yang Hong Mao yinjuan Zhan Weiwei Ma Chunyan Gu ying Chen Wu xie Mingxing Jiang Tianan Yuan lijun Department of Ultrasound Medicine Tangdu Hospital Air Force Medical University Xi’an Shaanxi China Department of Ultrasound Medicine The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou Zhejiang China Department of Ultrasound Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei China Department of Ultrasound Xi’an Hospital of Traditional Chinese Medicine Xi’an Shaanxi China Ultrasound Medical Diagnosis Center Shaanxi Provincial People’s Hospital Xi’an Shaanxi China Department of Ultrasound Hospital of Northwestern Polytechnical University Xi’an Shaanxi China Department of Ultrasound Xi’an No. Hospital The First Affiliated Hospital of Northwest University Xi’an Shaanxi China Department of Ultrasound Diagnosis The Second Affiliated Hospital Xi’an Medical College Xi’an Shaanxi China Department of Ultrasound Xi’an Gem Flower ChangQing Hospital Xi’an Shaanxi China Department of Ultrasound The Second Affiliated Hospital of Xi’an Jiaotong University China Xi’an Shaanxi China Department of Echocardiography First Affiliated Hospital of Xinjiang Medical University Urumqi Xinjiang China Department of Ultrasound Renmin Hospital of Wuhan University Wuhan Hubei China Department of Ultrasound Yan’an Hospital The Affiliated Hospital of Kunming Medical University Kunming Yunnan China Department of Ultrasound Yan’an University Xianyang Hospital Xianyang Shaanxi China Department of Function Examination Beijing University of Chinese Medicine Third Affiliated Hospital Beijing China Department of Ultrasound Xi’an Central Hospital Xi’an Shaanxi China Cadre’s Wards Ultrasound Department Diagnostic Ultrasound Center First Hospital of Jilin University Changchun Jilin China Department of Echocardiography Affiliated Hospital of Traditional Chinese Medicine of Xinjiang Medical University Urumqi Xinjiang China Department of Ultrasound First Affiliated Hospital of Anhui Medical University Hefei

Background: Carotid intima-media thickness (IMT) and diameter, stiffness, and wave reflections, are independent and important clinical biomarkers and risk predictors for cardiovascular diseases. The purpose of the present study was to establish nationwide reference values of carotid properties for healthy Chinese adults and to explore potential clinical ***: A total of 3053 healthy Han Chinese adults (1922 women) aged 18-79 years were enrolled at 28 collaborating tertiary centers throughout China between April 2021 and July 2022. The real-time tracking of common carotid artery walls was achieved by the radio frequency (RF) ultrasound system. The IMT, diameter, compliance coefficient, β stiffness, local pulse wave velocity (PWV), local systolic blood pressure, augmented pressure (AP), and augmentation index (AIx) were then automatically measured and reported. Data were stratified by age groups and sex. The relationships between age and carotid property parameters were analyzed by Jonckheere-Terpstra test and simple linear regressions. The major clinical determinants of carotid properties were identified by Pearson’s correlation, multiple linear regression, and analyses of ***: All the parameters of carotid properties demonstrated significantly age-related trajectories. Women showed thinner IMT, smaller carotid diameter, larger AP, and AIx than men. The β stiffness and PWV were significantly higher in men than women before forties, but the differences reversed after that. The increase rate of carotid IMT (5.5 μm/year in women and 5.8 μm/year in men) and diameter (0.03 mm/year in both men and women) were similar between men and women. For the stiffness and wave reflections, women showed significantly larger age-related variations than men as demonstrated by steeper regression slopes (allP for age by sex interaction linical determinants o

关键词： Intima-media thickness Arterial stiffness Reference values Ultrasound radio frequency signal Wave reflections

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小样本语义分割研究现状与分析

计算机学报 2024年第10期47卷 2417-2451页

作者：陈善娟于云龙李英明浙江大学信息与电子工程学院杭州310058

传统语义分割任务通常是数据驱动的,需要大规模密集标注样本训练,并且不能泛化到新类,因此在实际应用中受到很大限制.为了缓解传统语义分割中数据匮乏和泛化能力差的问题,人们提出小样本语义分割任务,在未见类别仅提供少量密集标注样本... 详细信息

传统语义分割任务通常是数据驱动的,需要大规模密集标注样本训练,并且不能泛化到新类,因此在实际应用中受到很大限制.为了缓解传统语义分割中数据匮乏和泛化能力差的问题,人们提出小样本语义分割任务,在未见类别仅提供少量密集标注样本的情况下实现新类分割,在医疗图像分割、自动驾驶等应用领域扮演着重要的角色,已成为计算机视觉领域的重要研究方向之一.本文从基础知识、模型算法和拓展应用等方面对自然图像领域的小样本语义分割研究展开调查,具体包含以下内容:(1)介绍了小样本语义分割的背景知识,包括它的由来、核心思想、概念知识、存在挑战、数据集和性能评价指标;(2)详细分析和比较当前小样本语义分割算法,根据推理过程中是否存在梯度回传将其分为基于优化和基于度量学习的方法,并归纳了其发展现状和不同算法的优缺点;(3)介绍了小样本语义分割与其他技术融合的任务,包括小样本实例分割、广义小样本分割、增量小样本分割、弱监督小样本分割及跨域小样本分割;(4)讨论了小样本语义分割任务仍存在的问题和未来展望.

关键词：小样本学习图像语义分割元学习迁移学习深度学习

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