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基于深度学习与特征点速度约束的室内动态SLAM方法

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中国惯性技术学报 2023年第5期31卷 438-443页

作者：刘丰宇程向红曹毅微惯性仪表与先进导航技术教育部重点实验室南京210096 东南大学仪器科学与工程学院南京210096

针对动态环境下同时定位与建图(SLAM)算法定位信息不准确、建图偏移严重的问题,提出一种深度学习与特征点速度约束相结合的室内动态SLAM方法。引入基于深度学习的潜在动态目标检测线程与基于ORB-LK光流金字塔的特征点速度计算线程。首先... 详细信息

针对动态环境下同时定位与建图(SLAM)算法定位信息不准确、建图偏移严重的问题,提出一种深度学习与特征点速度约束相结合的室内动态SLAM方法。引入基于深度学习的潜在动态目标检测线程与基于ORB-LK光流金字塔的特征点速度计算线程。首先,通过YOLO_v5算法对场景中潜在的动态目标进行识别判断,提供先验信息;然后,利用ORB-LK光流金字塔算法计算图像中特征点的相对速度,根据特征点速度约束判断潜在动态目标区域的真实动态性,更加合理地剔除动态特征点,提高视觉SLAM系统在室内动态环境下的定位精度和鲁棒性。实验结果表明,在TUM数据集中动态子序列下与ORB-SLAM2、Detect-SLAM、DS-SLAM相比,绝对轨迹均方根误差分别平均减少94.74%、51.95%、43.61%。

关键词：动态环境视觉SLAM 深度学习光流金字塔特征点速度约束

A multiple-tissue-specific magnetic resonance imaging model for diagnosing Parkinson’s disease: a brain radiomics study

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Neural Regeneration Research 2022年第12期17卷 2743-2749页

作者： Xiao-jun Guan Tao Guo Cheng Zhou Ting Gao Jing-Jing Wu Victor Han Steven cao Hong-Jiang Wei Yu-Yao Zhang Min Xuan Quan-Quan Gu Pei-Yu Huang Chun-Lei Liu Jia-Li Pu Bao-Rong Zhang Feng Cui Xiao-jun Xu Min-Ming Zhang Department of Radiology the Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina Department of Neurology the Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina Department of Electrical Engineering and Computer Sciences University of CaliforniaBerkeleyCAUSA Institute for Medical Imaging Technology School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina School of Information Science and Technology ShanghaiTech UniversityShanghaiChina Helen Wills Neuroscience Institute University of CaliforniaBerkeleyCAUSA Department of Radiology Hangzhou Hospital of Traditional Chinese MedicineHangzhouZhejiang ProvinceChina

Brain radiomics can reflect the characteristics of brain ***,the value of T1-weighted images,quantitative susceptibility mapping,and R2*mapping in the diagnosis of Parkinson’s disease(PD)was underestimated in previous *** this prospective study to establish a model for PD diagnosis based on brain imaging information,we collected high-resolution T1-weighted images,R2*mapping,and quantitative susceptibility imaging data from 171 patients with PD and 179 healthy controls recruited from August 2014 to August *** to the inclusion time,123 PD patients and 121 healthy controls were assigned to train the diagnostic model,while the remaining 106 subjects were assigned to the external validation *** extracted 1408 radiomics features,and then used data-driven feature selection to identify informative features that were significant for discriminating patients with PD from normal controls on the training *** informative features so identified were then used to construct a diagnostic model for *** constructed model contained 36 informative radiomics features,mainly representing abnormal subcortical iron distribution(especially in the substantia nigra),structural disorganization(e.g.,in the inferior temporal,paracentral,precuneus,insula,and precentral gyri),and texture misalignment in the subcortical nuclei(e.g.,caudate,globus pallidus,and thalamus).The predictive accuracy of the established model was 81.1±8.0%in the training *** the external validation dataset,the established model showed predictive accuracy of 78.5±2.1%.In the tests of identifying early and drug-naïve PD patients from healthy controls,the accuracies of the model constructed on the same 36 informative features were 80.3±7.1%and 79.1±6.5%,respectively,while the accuracies were 80.4±6.3%and 82.9±5.8%for diagnosing middle-to-late PD and those receiving drug management,*** accuracies for predicting tremor-dominant and non-tremor-dominant PD w

关键词： diagnosis imaging biomarker iron magnetic resonance imaging neuroimaging Parkinson’s disease quantitative susceptibility mapping R2*mapping radiomics T1-weighted imaging

Short-term effects of low-level PM_(2.5),PM_(10),O_(3),and tropical meteorological conditions on emergency department visits for respiratory diseases in Haikou,China

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Asian Pacific Journal of Tropical Medicine 2024年第7期17卷 317-328,I0010,I0011页

作者： Jichao Peng jun Chen Xinxin Wu Jin Qian Nan Li Yang yi Yue Huang juncai Lu Wenxing Zhang Zhengyu Li Zhao Li Min Li Xiaoran Liu School of Public Health Hainan Medical UniversityHaikou 571199China Danzhou People's Hospital Danzhou 571799China The Second Affiliated Hospital of Hainan Medical University Haikou 570105China The First Affiliated Hospital of Hainan Medical University Haikou 570102China Emergency and Trauma College Hainan Medical UniversityKey Laboratory of Emergency and Trauma of Ministry of EducationHaikou 571199China Hainan General Hospital Affiliated to Hainan Medical University Haikou 570311China

Objective:To assess the correlation between atmospheric pollutants,meteorological factors,and emergency department visits for respiratory diseases in Haikou ***:Daily data on atmospheric pollutants,meteorological factors,and emergency department visits for respiratory diseases in Haikou City from 2018 to 2021 were *** Spearman rank correlation test was used to analyze the correlation,and a distributed lag non-linear model was employed to analyze the health effects and lag impacts of environmental *** analyses were conducted based on sex and ***:According to the criteria of International Classification of Diseases(ICD-10:J00-J99),a total of 221913 cases were included,accounting for 21.3%of the total emergency department visits in Haikou *** every 1℃increase in temperature,the risk of emergency department visits increased by 1.029%(95%CI 1.016%-1.042%).Relative humidity greater than 80%reduced the risk of visits,while higher atmospheric pressure(>1010 hpa)also decreased the likelihood of daily emergency department *** concentrations of PM_(2.5)(30-50μg/m^(3)),PM10(>60μg/m^(3)),and O_(3)(75-125μg/m^(3))were associated with increased *** temperatures(>25℃)have a greater impact on females and children aged 0-14 years,while males are more sensitive to low atmospheric *** aged 65 and above exhibited increased sensitivity to O_(3)concentration,and the effects of PM2.5,PM10,and O_(3)are more pronounced in individuals over 14 years ***:Short-term exposure to high temperatures,particulate matter pollutants(PM_(2.5)and PM_(10)),and ozone(O_(3))is associated with increased emergency department visits for respiratory diseases.

关键词： Distributed lag nonlinear model Meteorological factors Air pollution Emergency department visits Respiratory diseases

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产品开发ProA一般Petri网模型研究

计算机集成制造系统 2009年第12期15卷 2328-2334页

作者：曹宜英秦现生王炜西北工业大学机电学院陕西西安710072

为了定量描述产品开发ProA的内部运行过程,更好地支持产品开发管理,构建了产品开发ProA的一般模型。深入剖析了产品开发ProA的内部运行机理;利用多色集合的着色原理对Petri网进行改进,形成了多色ProA Petri网方法。在此基础上,建立了产... 详细信息

为了定量描述产品开发ProA的内部运行过程,更好地支持产品开发管理,构建了产品开发ProA的一般模型。深入剖析了产品开发ProA的内部运行机理;利用多色集合的着色原理对Petri网进行改进,形成了多色ProA Petri网方法。在此基础上,建立了产品开发ProA的一般Petri网模型。最后,给出了该模型在汽车油泵单向阀测试器开发中的应用情况。

关键词：产品开发 ProA 多色Petri网 ProA一般Petri网模型

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复合固体推进剂颗粒脱湿损伤参数反演

推进技术 2016年第10期37卷 1977-1983页

作者：职世君曹付齐申志彬邢国强曹军伟中国空空导弹研究院河南洛阳471000 国防科技大学航天科学与工程学院湖南长沙410073

为确定复合固体推进剂颗粒脱湿损伤参数,采用分子动力学方法建立了复合固体推进剂颗粒夹杂模型,根据Surface-based cohesive方法,在高氯酸铵(AP)颗粒与基体之间的界面处设置接触损伤,对复合固体推进剂的细观损伤过程进行数值仿真计算。... 详细信息

为确定复合固体推进剂颗粒脱湿损伤参数,采用分子动力学方法建立了复合固体推进剂颗粒夹杂模型,根据Surface-based cohesive方法,在高氯酸铵(AP)颗粒与基体之间的界面处设置接触损伤,对复合固体推进剂的细观损伤过程进行数值仿真计算。将数值仿真得到的应力-应变曲线与试验曲线进行对比,建立颗粒脱湿损伤参数的优化目标函数,通过分步迭代计算,对颗粒脱湿损伤参数进行反演识别。结果表明:根据反演参数计算复合固体推进剂细观损伤过程,颗粒夹杂模型表现出的宏观应力-应变关系与试验结果吻合良好,说明双折线损伤模型可以近似表征复合固体推进剂的脱湿损伤。

关键词：固体推进剂细观力学界面损伤数值模拟参数反演

High Intensity Single-Mode Peak Observed in the Lasing Spectrum of InAs/GaAs Quantum Dot Laser

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Chinese Physics Letters 2013年第2期30卷 128-131页

作者： YUE Li GONG Qian YAN Jin-yi cao Chun-Fang LIU Qing-Bo WANG Yang CHENG Ruo-Hai WANG Hai-Long LI Shi-Guo State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050 Shandong Provincial Key Laboratory of Laser Polarization and Information Technology Department of PhysicsQufu Normal UniversityQufu 273165 Department of Electronic Communication and Technology Shenzhen Institute of Information TechnologyShenzhen 518172

We report on abnormal lasing spectra of InAs/GaAs quantum dot lasers,where a single-mode peak exists with optical intensity several times larger than that of other *** maximum side mode suppression ratio of the single-mode peak is measured to be 10.11 dB at 29℃ with injection current of 413 *** is found that the emergence of this abnormal lasing spectrum happens in a certain range of operation temperature and *** sharp increase in optical intensity of the single-mode peak is closely related to the disappearance of optical lasing modes located at the higher energy side of the enhanced mode.

关键词： InAs/GaAs lasing mode

Room temperature tensile deformation behavior of a Ni-based superalloy with high W content

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China Foundry 2021年第3期18卷 192-198页

作者： De-long Shu jun Xie Feng-jiang Zhang Gui-chen Hou Zhen-jiang Wang Shu-ling Xun Jin-jiang Yu Xiao-feng Sun yi-zhou Zhou Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

K416B Ni-based superalloy with high W content has good high temperature properties and low cost,which has a great development *** investigate the room temperature tensile property and the deformation feature of K416B superalloy,tensile testing at room temperature was carried out,and optical microscopy (OM),scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the deformation and damage *** show that the main room temperature tensile deformation features of the K416B nickel-based superalloy are dislocations slipping in the matrix and shearing into γ’ *** super-dislocations shearing into γ’ phase can form the anti-phase boundary two coupled (a/2) partial-dislocations or decompose into the configuration of two (a/3) partial dislocations plus stacking *** the later stage of tensile testing,the slip-lines with different orientations are activated in the grain,causing the stress concentration in the regions of block carbide or the porosity,and cracks initiate and propagate along these regions.

关键词： Ni-based superalloy high W content microstructure tensile behavior deformation feature

联合利用两种不同性质循环平稳的盲辨识盲均衡

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电子与信息学报 2007年第12期29卷 2919-2922页

作者：曹士坷张力军南京邮电大学通信工程系南京210003

针对SISO FIR信道,该文提出了一种盲辨识和盲均衡的方案,它可以联合利用调制引入循环平稳和过抽样引入循环平稳这两种不同性质的循环平稳。该方法的好处是发射端和接收端只需要一个天线,并且可以抑制较强的干扰。仿真结果验证了算法的... 详细信息

针对SISO FIR信道,该文提出了一种盲辨识和盲均衡的方案,它可以联合利用调制引入循环平稳和过抽样引入循环平稳这两种不同性质的循环平稳。该方法的好处是发射端和接收端只需要一个天线,并且可以抑制较强的干扰。仿真结果验证了算法的有效性。

关键词：盲辨识盲均衡抗干扰

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面向需求响应的电力通信网业务均衡与优化

中国电机工程学报 2020年第23期40卷 7635-7642页

作者：曹望璋祁兵李彬孙毅华北电力大学电气与电子工程学院北京市昌平区102206

基于需求响应业务在电力通信骨干网中的分布情况,该文提出一种新的业务均衡优化方法。首先建立需求响应业务和控制终端之间的一一映射关联关系,通过映射关系确定业务实际连接在执行需求响应负荷调度过程中所承载的负荷大小,设计业务均... 详细信息

基于需求响应业务在电力通信骨干网中的分布情况,该文提出一种新的业务均衡优化方法。首先建立需求响应业务和控制终端之间的一一映射关联关系,通过映射关系确定业务实际连接在执行需求响应负荷调度过程中所承载的负荷大小,设计业务均衡模型。然后利用分层序列法计算每个业务连接的重要度,根据自适应启发式方法松弛业务均衡模型中的优化目标,逐次规划每个需求响应业务连接。最后实现松弛条件下的需求响应业务均衡优解。仿真结果验证该文算法能用于解决需求响应业务连接过度密集分布所产生的可靠性问题。所提方法将业务连接按照控制响应量的大小均匀分布于网络中各条链路,提升了需求响应业务的可靠性。

关键词：电力通信网需求响应业务均衡优化可靠性