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基于U-net-BiLSTM-CRF的心律失常多目标检测

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计算机应用与软件 2024年第4期41卷 142-150页

作者：王雨轩朱俊江黄浩濮玉中国计量大学机电工程学院浙江杭州310018

由于卷积滤波尺寸等限制,U-net无法学习到心电(Electrocardiographic,ECG)信号的长时序关联性以及标签间的相关性。对此提出一种基于U-net-BiLSTM-CRF的心律失常多目标检测方法,可同时输出目标心拍所属类型和位置信息。使用U-net学习融... 详细信息

由于卷积滤波尺寸等限制,U-net无法学习到心电(Electrocardiographic,ECG)信号的长时序关联性以及标签间的相关性。对此提出一种基于U-net-BiLSTM-CRF的心律失常多目标检测方法,可同时输出目标心拍所属类型和位置信息。使用U-net学习融合特征,再将其输入到双向长短时记忆网络(Bi-directional Long Short-Term Memory,BiLSTM)中学习长时序依赖特征,最后使用条件随机场(Conditional Random Field,CRF)对标签间的关系建模,优化分类结果。依据ANSI/AAMI EC57:2012的心搏分类标准,对MIT-BIH心律失常数据库中共85609个心拍记录进行划分,在划分后数据集上的实验结果表明,该方法对心拍分类的准确率达99.11%,特异性为99.76%,灵敏度为97.21%,优于传统U-net在MIT-BIH心律失常数据库上的分类性能。

关键词：心律失常检测 U-net 双向长短时记忆网络条件随机场

High-cycle fatigue behavior of Co-based superalloy 9CrCo at elevated temperatures

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Chinese Journal of Aeronautics 2016年第5期29卷 1405-1413页

作者： Wan Aoshuang Xiong junjiang Lyu Zhiyang Li Kuang Du Yisen chen Kejiao Man Ziyu School of Transportation Science and Engineering Beihang University

A modified model is developed to characterize and evaluate high-cycle fatigue behavior of Co-based superalloy 9CrCo at elevated temperatures by considering the stress ratio effect. The model is informed by the relationship surface between maximum nominal stress, stress ratio and fatigue life. New formulae are derived to deal with the test data for estimating the parameters of the proposed model. Fatigue tests are performed on Co-based superalloy 9CrCo subjected to con- stant amplitude loading at four stress ratios of -1, -0.3, 0.5 and 0.9 in three environments of room temperature （i.e., about 25 ℃） and elevated temperatures of 530 ℃ and 620 ℃, and the interaction mechanisms between the elevated temperature and stress ratio are deduced and compared with each other from fractographic studies. Finally, the model is applied to experimental data, demonstrating the practical and effective use of the proposed model. It is shown that new model has good correlation with experimental results.

关键词： Elevated temperature Fatigue Metals and alloys SEM Stress ratio

Tear Resistance of Orthogonal Kevlar-PWF-reinforced TPU Film

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Chinese Journal of Aeronautics 2011年第1期24卷 113-118页

作者： BAI Jiangbo XIONG junjiang chenG Xu School of Transportation Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

This work seeks to investigate the notch sensitivity and fracture behaviour of orthogonal Kevlar-plain woven fabric （PWF）-reinforced thermoplastic polyurethanes （TPU） film applied to high altitude balloon. Four types of specimens are implemented to measure notched strength and fracture toughness by conducting static tension and tear tests on an MTS system respectively. The damage and failure mechanisms are discussed and the results for notched strength and tear resistance are evaluated and compared with each other. From the experiments, it is found that the notch sensitivity of the film increases with the increase in the size of the hole, but the notch sensitivity and the stress concentration of the notch are insignificant and there is a decrease of only about 4%-10% in tensile strength for the notched specimens with different hole sizes in diameter compared with the unnotched specimen. In contrast, the tear resistance containing a central slit with only 1 mm length is about half of tensile strength of the unnotched film, which implies that the tear resistance exists an significant notch sensitivity. The results of this study provide an insight into notch sensitivity and fracture behaviour of the Kevlar-PWF-reinforced TPU film and constitute a fundamental basis for the design of high altitude balloon.

关键词： fracture toughness notched strength thermoplastic polyurethanes film Kevlar fabric tear resistance

基于VMD-Hausdorff算法的小电流接地系统单相接地故障保护方法

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电瓷避雷器 2024年第1期 75-85,92页

作者：钟浩王俊江徐策陈斌王庆壮山东理工大学电气与电子工程学院山东淄博255000 山东科汇电力自动化股份有限公司山东淄博255000

为消除中性点接地方式、故障点过渡电阻阻值以及现有保护方法盲区等因素对小电流接地系统单相接地故障保护准确性的影响,提出了一种基于暂态信息量幅值特征差异,结合变分模态分解(Variational Mode Decomposition, VMD)与Hausdorff距离... 详细信息

为消除中性点接地方式、故障点过渡电阻阻值以及现有保护方法盲区等因素对小电流接地系统单相接地故障保护准确性的影响,提出了一种基于暂态信息量幅值特征差异,结合变分模态分解(Variational Mode Decomposition, VMD)与Hausdorff距离算法的单相接地故障保护方法。首先,通过分析单相接地故障暂态过程,明确了健全线路、故障线路出口侧以及健全区段、故障区段两端暂态零序电流幅值特征关系。其次通过变分模态分解提取暂态高频信号,并引入Hausdorff距离算法,计算零序电流暂态分量的幅值匹配度,通过与预设动作阈值比较,可有效判断故障线路与故障区段。仿真结果验证,本研究所提方法不受中性点接地方式与噪声干扰的影响,对于不同过渡电阻的接地故障均能准确判断故障线路与故障区段,仿真数据与实际故障录波均验证本研究所提方法具有较高的可靠性。

关键词：小电流接地故障暂态特征变分模态分解 Hausdorff距离保护方法

Material parameter modeling and solution technique using birth–death element for notched metallic panel repaired with bonded composite patch

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Chinese Journal of Aeronautics 2014年第2期27卷 445-452页

作者： Tong Lei Li Shiqiu Xiong junjiang School of Transportation Science and Engineering Beihang University

This paper seeks to outline a novel three-layer model and a new birth-dteath element solution technique to evaluate static strength of notched metallic panel repaired with bonded com- posite patch and to optimize material parameters. The higher order 3D, 8-node isotropic solid ele- ment and 8-node anisotropic layered solid element with three degrees of freedom per node are respectively implemented to model substrate panel, adhesive layer and composite patch to establish three-layer model of repaired panel. The new solving technique based on birth-death element is developed to allow solution of the stress pattern of repaired panel for identifying failure mode. The new model and its solution are used to model failure mode and residual strength of repaired panel, and the obtained results have a good agreement with the experimental findings. Finally, the influences of material parameter of adhesive layer and composite patch on the residual strength of repaired panel are investigated for optimizing material properties to meet operational and envi- ronmental constraints.

关键词： Birth-death elementBonding Bonding repair Composite patch Residual strength Three-layer model

Station 10 lymph node dissections in laparoscopic-assisted spleen-preserving radical gastrectomy for advanced proximal gastric cancer

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Chinese Journal of Cancer Research 2013年第4期25卷 465-467页

作者： Yong Li junjiang Wang The First Division of General Surgery Department Guangdong Academy of Medical SciencesGuangdong Genreral Hospital

D2 gastric resection has been increasingly recognized as the optimal surgical treatment for advanced gastric cancer. Dissection of the station 10 splenic lymph nodes is required in the treatment of advanced proximal gastric cancer. Based on vascular anatomy and anatomical plane of fascial space, integrated with our experience in station 10 splenic lymph node dissection in open surgery and proven skills of laparoscopic operation, we have successfully mastered the surgical essentials and technical keypoints in laparoscopic-assisted station 10 lymph node dissection.

关键词： Stomach neoplasm laparoscopy lymph node excision splenic hilar

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浅层膨胀土及其纤维改良土的剪切强度特性

浙江大学学报（工学版） 2024年第3期58卷 547-556,569页

作者：段君义吴俊江粟雨吕志涛林宇亮杨果林南昌大学工程建设学院江西南昌330031 中南大学土木工程学院湖南长沙410075

与膨胀土工程灾害密切相关的浅层膨胀土受到的围压通常较低,其力学特性有别于高围压下的情形.通过三轴剪切试验比较高、低围压下膨胀土的剪切行为及剪切强度的非线性特征,探讨聚丙烯纤维改良浅层膨胀土的剪切特性及加固机理.结果表明,... 详细信息

与膨胀土工程灾害密切相关的浅层膨胀土受到的围压通常较低,其力学特性有别于高围压下的情形.通过三轴剪切试验比较高、低围压下膨胀土的剪切行为及剪切强度的非线性特征,探讨聚丙烯纤维改良浅层膨胀土的剪切特性及加固机理.结果表明,浅层膨胀土剪切强度具有明显的非线性,可用幂函数表征.随着土体中水的质量分数增大和围压减小,膨胀土剪切强度非线性更加明显.采用高围压下的抗剪强度参数试验结果会导致浅层饱和膨胀土的黏聚力被高估225.7%、内摩擦角被低估42.5%.掺入纤维后膨胀土的剪切强度明显提高,提升幅度与土体中的三维纤维网状结构的形成度有关.增大纤维长度可以有效降低剪切强度衰减率,继而消弱膨胀土的应变软化效应;过长的纤维在膨胀土内容易弯曲和扭折,会导致纤维-膨胀土界面作用随着土体变形而逐渐劣化.

关键词：低围压膨胀土剪切强度纤维网状结构应变软化纤维-土体界面作用

A multi-resource scheduling scheme of Kubernetes for IIoT

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Journal of Systems Engineering and Electronics 2022年第3期33卷 683-692页

作者： ZHU Lin LI junjiang LIU Zijie ZHANG Dengyin Jiangsu Key Laboratory of Broadband Wireless Communication and Internet of Things Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing 210003China

With the rapid development of data applications in the scene of Industrial Internet of Things(IIoT),how to schedule resources in IIoT environment has become an urgent problem to be *** to benefit of its strong scalability and compatibility,Kubernetes has been applied to resource scheduling in IIoT ***,the limited types of resources,the default scheduling scoring strategy,and the lack of delay control module limit its resource scheduling *** address these problems,this paper proposes a multi-resource scheduling(MRS)scheme of Kubernetes for *** MRS scheme dynamically balances resource utilization by taking both requirements of tasks and the current system state into ***,the experiments demonstrate the effectiveness of the MRS scheme in terms of delay control and resource utilization.

关键词： Industrial Internet of Things(IIoT) Kubernetes resource scheduling time delay

Analytical Solutions for Predicting Tensile and Shear Moduli of Triaxial Weave Fabric Composites

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Acta Mechanica Solida Sinica 2016年第1期29卷 59-77页

作者： Jiangbo Bai junjiang Xiong Meng Liu Ziyu Man School of Transportation Science and Engineering Beihang University Beijing 100083 China

Novel micromechanical curved beam models were presented for predicting the ten- sile and shear moduli of triaxial weave fabric （TWF） composites by considering the interactions between the triaxial yarns of 0° and ±60° The triaxial yarns in micromechanieal representative unit cell （RUC） were idealized as curved beams with a path depicted using the sinusoidal shape functions, and the tensile and shear moduli of TWF composites were derived by means of the strain energy approach founded on micromechanics. In order to validate the new models, the predictions were compared with the experimental data from literature. It was shown that the predictions from the new model agree well with the experimental results. Using these models, the tensile and shear properties of TWF composites could be predicted based only on the properties of basic woven fabric.

关键词： triaxial weave fabric (TWF) composite elastic properties tension modulus shearmodulus