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高灵敏度SiC动态高温压力传感器仿真研究

传感器与微系统 2024年第1期43卷 62-64,68页

作者：李强梁庭雷程李永伟周行健中北大学动态测试技术国家重点实验室山西太原030051 太原工业学院自动化系山西太原030051

为了提高碳化硅(SiC)动态高温压力传感器的灵敏度,采用p型SiC材料,同时对传感器的敏感单元的不同结构———方膜和圆膜,利用Ansys软件进行了静力学仿真与分析,并完成了敏感芯片的尺寸设计。仿真结果表明:优化后的传感器输出灵敏度为14.2... 详细信息

为了提高碳化硅(SiC)动态高温压力传感器的灵敏度,采用p型SiC材料,同时对传感器的敏感单元的不同结构———方膜和圆膜,利用Ansys软件进行了静力学仿真与分析,并完成了敏感芯片的尺寸设计。仿真结果表明:优化后的传感器输出灵敏度为14.2μV/(V·kPa)。在100~600℃内非线性误差小于1.53%。动态仿真表明:传感器的固有频率为481kHz,传感器可以在160kHz高频环境中安全工作,该结果为进一步制备SiC高温压力传感器奠定了理论支撑。

关键词：碳化硅高温压力传感器有限元分析高灵敏度

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基于CT影像组学模型在预测自发性脑出血不良预后中的应用价值

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现代实用医学 2024年第6期36卷 727-731页

作者：裴磊柯君丽徐星建温州医科大学附属衢州医院(衢州市人民医院) 浙江省衢州324002

目的探讨基于CT影像组学模型在预测自发性脑出血不良预后中的价值。方法回顾性收集衢州市人民医院放射科2020年1月至2023年2月行头颅CT平扫的自发性脑出血患者,收集其影像及临床资料。采用最小冗余最大相关算法(mRMR)及最小绝对收缩和... 详细信息

目的探讨基于CT影像组学模型在预测自发性脑出血不良预后中的价值。方法回顾性收集衢州市人民医院放射科2020年1月至2023年2月行头颅CT平扫的自发性脑出血患者,收集其影像及临床资料。采用最小冗余最大相关算法(mRMR)及最小绝对收缩和选择算子(LASSO)回归模型选择影像组学特征,使用单因素及多因素回归分析构建临床模型,以识别脑出血不良预后的独立危险因素。通过整合临床模型和影像组学模型,生成联合模型并构建Nomogram图可视化评估不良预后的风险系数。采用受试者工作特征(ROC)曲线、校准曲线和决策曲线分析及评估模型的预测效能。结果本研究共纳入117例脑出血患者,根据7∶3的比例,82例被分为训练组,35例被分为验证组,从1130个影像组学特征中筛选出11个用于生成影像组学模型。通过单因素及多因素回归分析确定不良预后相关的4个独立风险因素:性别、高血压、格拉斯哥昏迷评分(GCS)和血肿体积。联合模型、影像组学模型和临床模型在训练组中的曲线下面积(AUC)值分别为0.856、0.795和0.725,在验证组中分别为0.881、0.832和0.673。校准曲线显示联合模型在预测脑出血的不良预后和实际结果方面具有极好的一致性和校准性。决策曲线分析结果提示联合模型较影像组学模型和临床模型获得更高的净效益。结论基于CT影像组学模型结合临床模型构建的联合模型在预测自发性脑出血不良预后中有较高的诊断效能和可靠性。

关键词：脑出血 X线计算机,体层摄影术诺莫图机器学习影像组学

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联合视觉分组的图像中文描述

微电子学与计算机 2024年第8期41卷 73-80页

作者：郝子娴汪兴建杨有重庆师范大学计算机与信息科学学院重庆401331 重庆青年职业技术学院重庆400712 重庆师范大学重庆国家应用数学中心重庆401331

针对图像描述任务中使用的编码器提取图像细粒度语义特征不充分,导致模型生成的描述内容粗糙而文本细腻度不足的问题,提出了一种联合视觉分组的图像中文描述模型。模型采用编解码结构,编码阶段,使用两种方式实现图像全局语义和局部细节... 详细信息

针对图像描述任务中使用的编码器提取图像细粒度语义特征不充分,导致模型生成的描述内容粗糙而文本细腻度不足的问题,提出了一种联合视觉分组的图像中文描述模型。模型采用编解码结构,编码阶段,使用两种方式实现图像全局语义和局部细节两类特征的提取。首先,使用对比语言图像预训练编码器提取图像的潜在语义信息;其次,结合视觉分组的思想将图像中各物体类别划分为不同规则大小的视觉片段,以此提取图像细节特征。最后。对编码器得到的两类特征进行融合,并通过映射网络转换为描述文本的前缀信息,再嵌入到语言模型中。解码阶段,使用语言模型GPT-2生成图像描述。与相关文献的模型相比,所提模型在BLEU-1到BLEU-4评价指标上分别获得了0.815、0.711、0.616和0.532,达到了最佳性能。在AIC-ICC数据集上进行仿真实验,结果表明所提出模型生成的描述文本更准确、更流畅。

关键词：图像中文描述视觉分组特征融合图像语义编解码器

Modeling and analysis of mover gaps in tubular moving-magnet linear oscillating motors

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Chinese Journal of Aeronautics 2018年第5期31卷 927-940页

作者： Xuesong luO Chao ZHANG Shaoping WANG Enrico ZIO xingjian WANG School of Automation Science and Electrical Engineering Beihang University Energy Department-Nuclear Section Polytechnic of Milan

A tubular moving-magnet linear oscillating motor（TMMLOM） has merits of high efficiency and excellent dynamic capability. To enhance the thrust performance, quasi-Halbach permanent magnet（PM） arrays are arranged on its mover in the application of a linear electro-hydrostatic actuator in more electric aircraft. The arrays are assembled by several individual segments, which lead to gaps between them inevitably. To investigate the effects of the gaps on the radial magnetic flux density and the machine thrust in this paper, an analytical model is built considering both axial and radial gaps. The model is validated by finite element simulations and experimental *** of the magnetic flux are described in condition of different sizes of radial and axial gaps. Besides, the output force is also discussed in normal and end windings. Finally, the model has demonstrated that both kinds of gaps have a negative effect on the thrust, and the linear motor is more sensitive to radial ones.

关键词： Air-gap flux density Linear motor Mover gaps Quasi-Halbach array Thrust output Tubular moving-magnet linear oscillating motor(TMMLOM)

A high-fidelity design methodology using LES-based simulation and POD-based emulation:A case study of swirl injectors

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Chinese Journal of Aeronautics 2018年第9期31卷 1855-1869页

作者： xingjian WANG Shiang-Ting YEH Yu-Hung CHANG Vigor YANG School of Aerospace Engineering Georgia Institute of Technology

Engineering design is undergoing a paradigm shift from design for performance to design for affordability, operability, and durability, seeking multi-objective optimization. To facilitate this transformation, significantly extended design freedom and knowledge must be available in the early design stages. This paper presents a high-fidelity framework for design and optimization of the liquid swirl injectors that are widely used in aerospace propulsion and power-generation systems. The framework assembles a set of techniques, including Design Of Experiment(DOE), high-fidelity Large Eddy Simulations(LES), machine learning, Proper Orthogonal Decomposition(POD)-based Kriging surrogate modeling(emulation), inverse problem optimization, and uncertainty quantification. LES-based simulations can reveal detailed spatiotemporal evolution of flow structures and flame dynamics in a high-fidelity manner, and identify important injector design parameters according to their effects on propellant mixing, flame stabilization, and thermal *** a given a space of design parameters, DOE determines the number of design points to perform LES-based simulations. POD-based emulations, trained by the LES database, can effectively explore the design space and deduce an optimal group of design parameters in a turn-around time that is reduced by three orders of magnitude. The accuracy of the emulated results is validated, and the uncertainty of prediction is quantified. The proposed design methodology is expected to profoundly extend the knowledge base and reduce the cost for initial design stages.

关键词： Emulation High-fidelity design Kriging Large Eddy Simulation(LES) Proper Orthogonal Decomposition(POD) Swirl injector

Parametric identification of time-varying systems from free vibration using intrinsic chirp component decomposition

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Acta Mechanica Sinica 2020年第1期36卷 188-205页

作者： Sha Wei Shiqian Chen xingjian Dong Zhike Peng Wenming Zhang School of Mechanics and Engineering Science Shanghai UniversityShanghai200072China Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai200072China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai UniversityShanghai200072China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240China

Time-varying systems are applied extensively in practical applications,and their related parameter identification techniques are of great significance for structural health monitoring of time-varying *** improve the identification accuracy for time-varying systems,this study puts forward a novel parameter identification approach in the time-frequency domain using intrinsic chirp component decomposition(ICCD).ICCD is a powerful tool for signal decomposition and parameter extraction,with good signal reconstruction capability in a high-noise *** maintain good identification effects for the time-varying system in a noisy environment,the proposed method introduces a redundant Fourier model for the non-stationary signal,including instantaneous frequency(IF)and instantaneous amplitude(IA).The accuracy and effectiveness of the proposed approach are demonstrated by a single-degree-of-freedom system with three types of time-varying parameters,as well as an example of a multi-degree-of-freedom *** effects of different levels of measured noise on the identified results are also discussed in *** results show that the proposed method is very effective in tracking the smooth,periodical,and non-smooth variations of time-varying systems over the entire identification time period even when the response signal is contaminated by intense noise.

关键词： System identification Time-varying system Time-frequency domain Intrinsic chirp component decomposition

Variable load failure mechanism for high-speed load sensing electro-hydrostatic actuator pump of aircraft

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Chinese Journal of Aeronautics 2018年第5期31卷 949-964页

作者： Cun SHI Shaoping WANG xingjian WANG Yixin ZHANG School of Automation Science and Electrical Engineering Beihang University

This paper presents a novel transient lubrication model for the analysis of the variable load failure mechanism of high-speed pump used in Load Sensing Electro-Hydrostatic Actuator（LS-EHA）. Focusing on the slipper/swashplate pair partial abrasion, which is considered as the dominant failure mode in the high-speed condition, slipper dynamic models are established. A forth sliding motion of the slipper on the swashplate surface is presented under the fact that the slipper center of mass will rotate around the center of piston ball when the swashplate angle is dynamically adjusted. Besides, extra inertial tilting moments will be produced for the slipper based on the theorem on translation of force, which will increase rapidly when LS-EHA pump operates under highspeed condition. Then, a dynamic lubricating model coupling with fluid film thickness field, temperature field and pressure field is proposed. The deformation effects caused by thermal deflection and hydrostatic pressure are considered. A numerical simulation model is established to validate the effectiveness and accuracy of the proposed model. Finally, based on the load spectrum of aircraft flight profile, the variable load conditions and the oil film characteristics are analyzed, and series of variable load rules of oil film thickness with variable speed/variable pressure/variable displacement are concluded.

关键词： Coupling lubrication model Electro-Hydrostatic Actuator (EHA) High-speed pump Partial abrasion Slipper pair Variable load

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某三甲专科医院不良事件分析及对策研究

江苏卫生事业管理 2024年第7期35卷 961-964页

作者：王茜夏曼高行健天津市胸科医院投诉管理中心天津300222

目的:通过对医疗机构发生医疗质量安全不良事件进行深入研究,有针对性地探寻有效的预防策略,增强医院医疗安全管理水平。方法:采用回顾性分析研究方法,对2021年至2023年天津某三甲专科医院通过OA系统上报的401起不良事件进行级别、数量... 详细信息

目的:通过对医疗机构发生医疗质量安全不良事件进行深入研究,有针对性地探寻有效的预防策略,增强医院医疗安全管理水平。方法:采用回顾性分析研究方法,对2021年至2023年天津某三甲专科医院通过OA系统上报的401起不良事件进行级别、数量、类别等方面分析。结果:2021-2023年不良事件报告例数呈现逐年上升趋势,且不良事件主要集中在Ⅲ级与Ⅳ级不良事件,器械管理类不良事件的上报量最多,占比35.16%。结论:不断完善医疗质量安全管理体系,建立非惩罚性的不良事件激励上报机制,强化医务人员质量安全教育和培训,借助信息化手段建立大数据挖掘工具平台,确保患者的生命安全。

关键词：医疗安全不良事件医院管理对策研究

交互设计类课程中的思政元素挖掘与融合路径探索

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设计 2024年第17期37卷 74-77页

作者：张晶施行健郁舒兰南京林业大学家居与工业设计学院

针对当前智能互联网时代背景下的“设计强国”方针,探析了交互设计类课程中与时俱进的思政元素挖掘机制与路径融合模式。从交互设计类课程“学科交叉、科艺并举”的特点和课程体系出发,对数智技术赋能下的课程思政实施路径进行了深入探... 详细信息

针对当前智能互联网时代背景下的“设计强国”方针,探析了交互设计类课程中与时俱进的思政元素挖掘机制与路径融合模式。从交互设计类课程“学科交叉、科艺并举”的特点和课程体系出发,对数智技术赋能下的课程思政实施路径进行了深入探究,提出了“先挖掘、再融合”的总思路,并以笔者所在教学团队的实际教学情况为例,进行应用示例。阐明了挖掘和凝练交互设计类课程中思政元素的具体方法与措施,并从培养方案、教学内容、教学方法、评价方法4个层面提出了行之有效的融合路径和具体方法及示例。为建设新时代交互设计类课程的思政育人工作提供了参考。

关键词：交互设计课程思政教育创新思政元素融合路径