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中风后抑郁的中医诊疗研究进展

光明中医 2024年第10期39卷 2101-2104页

作者：王泰勇淄博市中医医院脑病科

中风后抑郁（PSD）是中风后常见并发症之一，其病因病机多为中风后脑部受损，脏腑亏虚，情志内伤。中风后抑郁严重影响了卒中患者认知功能及神经功能恢复。西医治疗中风后抑郁大多以抗抑郁药物为主要手段。中医治疗中风后抑郁多采用针... 详细信息

中风后抑郁（PSD）是中风后常见并发症之一，其病因病机多为中风后脑部受损，脏腑亏虚，情志内伤。中风后抑郁严重影响了卒中患者认知功能及神经功能恢复。西医治疗中风后抑郁大多以抗抑郁药物为主要手段。中医治疗中风后抑郁多采用针刺、中药、艾灸、音乐疗法等，具有费用低、操作简便、毒副作用少等特点。此文从中风后抑郁的病因病机、中医治疗等方面入手，综述近年来中医治疗脑卒中后抑郁的研究进展，以期为临床治疗提供新的思路和参考。

关键词：中风抑郁中医药疗法综述

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基于改进三角函数加减速的一步拐角过渡法

天津大学学报（自然科学与工程技术版） 2024年第10期57卷 1001-1009页

作者：王太勇贾松辉陈木正天津大学机械工程学院天津300350

加减速控制是数控系统的关键技术之一,影响着零件加工时的高效性和平稳性,同时由于传统数控系统在加工复杂的曲线曲面时,需要生成的大量连续微线段,这不仅增加了数控系统的负担,且在拐角处仅G0连续,导致在拐角处频繁加减速和机床振动,... 详细信息

加减速控制是数控系统的关键技术之一,影响着零件加工时的高效性和平稳性,同时由于传统数控系统在加工复杂的曲线曲面时,需要生成的大量连续微线段,这不仅增加了数控系统的负担,且在拐角处仅G0连续,导致在拐角处频繁加减速和机床振动,降低零件加工效率和加工质量.两步法拐角过渡是先进行轨迹光顺再进行速度规划,不仅步骤繁琐,而且降低了加工效率.因此,针对传统三角函数中最大加加速度只存在峰值导致加工效率降低的问题,本文先对加减速连续性较好的传统三角函数加减速控制算法进行改进,以sin^(2)x作为加加速度的基函数建立加减速规划的模型,并在其运动模型中增加匀加加速度加减速阶段.针对数控加工中连续微线段拐角处加工效率低、插补轨迹连续性低的问题,提出了新的一步法拐角过渡方法.该方法是通过一步法拐角过渡算法在速度规划阶段直接完成轨迹光顺.最后根据轮廓误差和机床各轴动态性能的限制对过渡时间、速度、加速度及加加速度进行约束.实验证明,提出的方法能够进一步提高加工中的加减速柔性,能够利用最大加加速度持续加减速,且在保证加工效率的基础上提高伺服控制的跟随精度,使得误差检测的精度能够满足要求.

关键词：拐角过渡三角函数加减速柔性加减速数控系统

面向高后果区工程车辆视觉检测的YOLO-MMCE算法

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油气储运 2024年第9期43卷 1031-1038页

作者：孙卉梅刘路王德刚王太勇天津职业技术师范大学机械工程学院天津市300222 国家管网集团北方管道有限责任公司长沙输油气分公司天津大学机械工程学院

【目的】高后果区大型施工现场的工程车辆给埋地管道带来严重的安全隐患。针对当前常用方法在工程车辆重叠目标检测和日照变化场景下的目标检测方面存在漏检率高、检测精度低的问题,以挖掘机、装载机、压路机及重型货车4类常见工程车辆... 详细信息

【目的】高后果区大型施工现场的工程车辆给埋地管道带来严重的安全隐患。针对当前常用方法在工程车辆重叠目标检测和日照变化场景下的目标检测方面存在漏检率高、检测精度低的问题,以挖掘机、装载机、压路机及重型货车4类常见工程车辆作为识别对象,提出了一种基于改进YOLOv5的工程车辆目标检测方法YOLO-MMCE。【方法】采用Mosaic十Mixup结合的数据增强方式,增强对不同场景的适应能力,提高模型在实际复杂环境和模糊情况下的鲁棒性和泛化性。针对目标重叠和光照变化导致的特征不明显问题,在YOLOv5网络模型中引入坐标注意力(CoordinateAttention,CA)机制,增强网络模型的特征提取能力;为了提升预测边框回归精度,引入了高效率交并比(Efficient Intersection overUnion,EIOU)函数,计算预测框与真实框的宽高差异值并取代纵横比,进一步提高算法检测精度。【结果】以兰郑长成品油管道高后果区监控摄像机获取的施工现场照片为数据集,对YOLO-MMCE算法进行验证。结果表明,对YOLOv5算法3个方面的改进均能提高其在实际工况下工程车辆目标检测的精度,总体平均精度均值(MeanAveragePrecision,mAP)达到84.8%,比原始YOLOv5算法提高了6.9%。对挖掘机、装载机、压路机及重型货车的目标检测mAP分别提高了4.4%、7.5%、9.5%、6.0%。【结论】YOLO-MMCE算法有效解决了重叠目标检测和日照变化场景下的工程车辆目标检测问题,具备实际应用价值。(图3,表5,参28)

关键词： YOLOv5 工程车辆数据增强坐标注意力机制损失函数

滚珠丝杠进给系统刚柔耦合动力学建模与时变动态特性分析

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机床与液压 2024年第13期52卷 176-188页

作者：张欣雨赵巍张雷王太勇天津职业技术师范大学天津市高速切削与精密加工重点实验室天津300222 天津商业大学机械工程学院天津300134 天津市天森智能设备有限公司天津300300 天津大学机械工程学院天津300354

数控机床运行过程中,多轴滚珠丝杠进给系统的刚度和惯量会随着各轴位姿的变化而变化,致使其动态特性呈时变的特点。多轴滚珠丝杠进给系统时变动态特性的高保真建模与分析已成为数控机床轮廓误差精准预测的瓶颈难题之一。针对这一难题,... 详细信息

数控机床运行过程中,多轴滚珠丝杠进给系统的刚度和惯量会随着各轴位姿的变化而变化,致使其动态特性呈时变的特点。多轴滚珠丝杠进给系统时变动态特性的高保真建模与分析已成为数控机床轮廓误差精准预测的瓶颈难题之一。针对这一难题,提出基于拉格朗日方程与Ritz级数法的滚珠丝杠进给系统刚柔耦合动力学建模与分析方法。以某型号五轴加工中心的两轴滚珠丝杠进给系统为具体对象,重点考虑丝杠本体轴扭方向的连续弹性体变形影响,采用拉格朗日方程建立滚珠丝杠进给系统的刚柔耦合动力学模型,并采用Ritz级数法对方程求解,得到动力学模型的数值解。利用所建立的动力学模型分析进给轴位姿对两轴进给系统固有频率和模态振型的影响,发现各阶固有频率和模态振型随进给轴位姿的变化规律与对应阶次的主导轴有关。随着主导轴进给台由固定端移动至支撑端,对应阶次的固有频率逐渐减小,对应阶次的振型中丝杠本体的弹性振动幅值逐渐增大。此外,两轴进给系统的低阶模态振型主要由承载轴主导,高阶模态振型主要由附属于承载轴的子轴主导。最后,通过模态实验对所提方法进行应用验证,证明所建立动力学模型的准确性。研究结果对数控机床轮廓误差的精准预测具有重要参考价值。

关键词：滚珠丝杠进给系统刚柔耦合动力学建模时变动态特性模态实验

Application of Stochastic Resonance Signal Recovery

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 542-549页

作者： ZHANG Ying wang taiyong LENG Yonggang DENG Hui Tianjin Key Laboratory of Advanced Manufacturing Technologies and Equipments Tianjin University Tianjin 300072 China School of Mechanical Engineering Tianjin University Tianjin 300072 China Textiles School Tianjin Polytechnic University Tianjin 300160 China

Stochastic resonance（SR） enhances the nonlinear system behavior with the assistance of noise, including the sensitivity and selectivity of the response to the exterior stimulus. The energy-transfer mechanism makes the weak information revealed in the output spectrum, while the time-waveform is distorted. The distortion analysis was made both from the particle＇s dynan-fics and signal processing. The factors causing the deviation in the output are presented and the function of the recovery system is proposed. By the investigation of the particle＇s motion track in the bistable system and the suggested recovery system, the influences of noise and system parameters on the recovery course were discussed. Moreover, the pulse distortion appearing the recovery waveform caused by the particle＇s transitions at the bistable potential＇ inflexions was explained. Due to different characteristics, cascaded-bistable SR or mono-stable SR was introduced to process different types of signals. The final recovery signal is just the suggested recovery system＇s response to the SR output. Meanwhile, the recovery system is optional, as parameter-tuned or parameter-fixed. Since the method requires no average processing, it is applicable to a single sample with limited length. The numerical simulations reveal that the SR recovery method can recover the waveform containing weak information submerged ha noise effectively. The engineering application to the vibration analysis of metal cutting chose the combination of mono-stable SR and the parameter-fixed recovery system. Because the optimal SR state is not required strongly, the system parameters are tuned in a wider range than the traditional SR processing methods.

关键词： bistable stochastic resonance signal recovery cascaded-bistable system parameter-tuning noise

数控机床多维度多层级数字孪生建模方法及应用

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制造技术与机床 2024年第10期 48-56页

作者：张雷何佳豪李智威姚梦琪王太勇天津商业大学机械工程学院天津300134 天津大学机械工程学院天津300354

针对数字孪生建模技术在数控机床领域的工程实践中实施难度大、成本高等问题,提出数控机床多维度多层级数字孪生建模方法,并开发数字孪生系统,实现数控机床运行过程的可视化。首先,从物理实体、数字孪生模型、信息物理融合数据和服务4... 详细信息

针对数字孪生建模技术在数控机床领域的工程实践中实施难度大、成本高等问题,提出数控机床多维度多层级数字孪生建模方法,并开发数字孪生系统,实现数控机床运行过程的可视化。首先,从物理实体、数字孪生模型、信息物理融合数据和服务4个维度以及几何、物理、行为和数据4个层级构建数控机床数字孪生模型;其次,基于该方法设计并开发数控机床数字孪生系统,实现数字孪生建模技术的软件化;最后,以某型数控机床为应用案例,采用NC代码控制机床实体运动,借助数字孪生模型与机床实体间的连接关系,驱动机床模型进行运动仿真,并将模型运行状态和各项数据进行可视化展示。结果表明系统各项功能均正常运行,所提方法具备可行性,为数字孪生建模技术在数控机床领域的工程应用提供参考。

关键词：数控机床数字孪生可视化轮廓误差

NUMERICAL APPROACH TO DETERMINING INSTANTANEOUS CONTACT REGION FOR CONJUGATE SURFACES

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Chinese Journal of Mechanical Engineering 2008年第4期21卷 15-17页

作者： wang taiyong LI Jingcai HE Gaiyun FAN Shengbo HAO Yongjiang Key Laboratory of AdvancedManufacturing Technologies and Equipments Tianjin University Tianjin 300072 China

According to the defect of traditional method of determining instantaneous contact regions for conjugate surfaces, a numerical approach to the determination is proposed. A local coordinate system is built by using the surface unit tangent and unit normal at the contact point. Considering that the gap forming the boundary of instantaneous contact region in the direction of the common normal vectors is given, a system of nonlinear equations is built to find the instantaneous contact boundary in local coordinate system, a modified Powell＇s hybrid algorithm of finite-difference approximation to the Jacobian used to solve the system. The new method simplifies the task of determining instantaneous contact regions without calculating curvatm＇e and relative curvature. The validity of the proposed approach is verified by an example of hypoid gears.

关键词： Tooth contact analysis Conjugate surfaces Numerical solutions

ALGORITHM FOR SPHERICITY ERROR AND THE NUMBER OF MEASURED POINTS

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Chinese Journal of Mechanical Engineering 2006年第3期19卷 460-463页

作者： HE Gaiyun wang taiyong ZHAO Jian YU Baoqin LI Guoqin School of Mechanical Engineenng Tianjin University Tianjin 300072 China

The data processing technique and the method determining the optimal number of measured points are studied aiming at the sphericity error measured on a coordinate measurement machine （CMM）. The consummate criterion for the minimum zone of spherical surface is analyzed first, and then an approximation technique searching for the minimum sphericity error from the form data is studied. In order to obtain the minimum zone of spherical surface, the radial separation is reduced gradually by moving the center of the concentric spheres along certain directions with certain steps. Therefore the algorithm is precise and efficient. After the appropriate mathematical model for the approximation technique is created, a data processing program is developed accordingly. By processing the metrical data with the developed program, the spherical errors are evaluated when different numbers of measured points are taken from the same sample, and then the corresponding scatter diagram and fit curve for the sample are graphically represented. The optimal number of measured points is determined through regression analysis. Experiment shows that both the data processing technique and the method for determining the optimal number of measured points are effective. On average, the obtained sphericity error is 5.78 μm smaller than the least square solution, whose accuracy is increased by 8.63%; The obtained optimal number of measured points is half of the number usually measured.

关键词： Sphericity error Minimum zone Data processing Scatter diagram Fit curve

Improved Pattern Tree for Incremental Frequent-Pattern Mining

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Transactions of Tianjin University 2010年第2期16卷 129-134页

作者：周明王太勇 School of Mechanical Engineering Tianjin University

By analyzing the existing prefix-tree data structure, an improved pattern tree was introduced for processing new transactions. It firstly stored transactions in a lexicographic order tree and then restructured the tree by sorting each path in a frequency-descending order. While updating the improved pattern tree, there was no need to rescan the entire new database or reconstruct a new tree for incremental updating. A test was performed on synthetic dataset T1014D100K with 100 000 transactions and 870 items. Experimental results show that the smaller the minimum sup- port threshold, the faster the improved pattern tree achieves over CanTree for all datasets. As the minimum support threshold increased from 2% to 3.5%, the runtime decreased from 452.71 s to 186.26 s. Meanwhile, the runtime re- quired by CanTree decreased from 1 367.03 s to 432.19 s. When the database was updated, the execution time of im- proved pattern tree consisted of construction of original improved pattern trees and reconstruction of initial tree. The experiment results showed that the runtime was saved by about 15% compared with that of CanTree. As the number of transactions increased, the runtime of improved pattern tree was about 25% shorter than that of FP-tree. The improved pattern tree also required less memory than CanTree.

关键词： data mining association rules improved pattern tree incremental mining