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车辆主动悬架自适应变论域T-S模糊控制研究
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作者 李韶华 季广港 +1 位作者 冯桂珍 王贺 《振动.测试与诊断》 EI CSCD 北大核心 2024年第4期733-739,828,共8页
针对传统变论域模糊控制存在过度依赖专家经验、伸缩因子参数不能自适应调整的问题,提出一种车辆主动悬架自适应变论域T-S模糊控制策略,从而提高车辆的行驶平顺性。结合神经网络和T-S模糊推理建立基于自适应神经模糊推理的一阶T-S模糊... 针对传统变论域模糊控制存在过度依赖专家经验、伸缩因子参数不能自适应调整的问题,提出一种车辆主动悬架自适应变论域T-S模糊控制策略,从而提高车辆的行驶平顺性。结合神经网络和T-S模糊推理建立基于自适应神经模糊推理的一阶T-S模糊控制器,利用神经网络的自学习特性产生完善的模糊规则,进而在传统函数型伸缩因子的基础上,将系统误差和误差变化率作为动态参数引入伸缩因子中,实现伸缩因子参数的自适应调整,解决了传统函数型伸缩因子因参数确定难度大导致控制效果差的问题。通过随机工况下的仿真分析和基于相似理论的缩尺实验,对所提出算法的有效性和工况自适应性进行了验证。结果表明,所提出的自适应变论域T-S模糊控制策略具有较强的工况适应性,在不同车速、路面激励下均可有效提高车辆的平顺性并保证轮胎接地安全性。 展开更多
关键词 主动悬架 变论域 伸缩因子 T-s模糊控制 神经模糊系统
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基于B/S架构的远程会诊质控系统的设计与应用
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作者 路阳 段燕 张雪 《中国卫生标准管理》 2024年第13期1-6,共6页
目的研发远程会诊质控系统,在区域内实现远程会诊质控、管理、监管、考评、统计和持续改进的信息化。方法2020年,组建多学科团队,运用智力激励法和专题小组讨论法,基于B/S架构研发远程会诊质控系统,与既有远程会诊信息系统完全嵌合兼容... 目的研发远程会诊质控系统,在区域内实现远程会诊质控、管理、监管、考评、统计和持续改进的信息化。方法2020年,组建多学科团队,运用智力激励法和专题小组讨论法,基于B/S架构研发远程会诊质控系统,与既有远程会诊信息系统完全嵌合兼容,满足远程会诊全流程质量管理的功能需求。结果针对远程会诊质控工作要求,系统设计研发了质控管理、质控考评、实时监管、统计分析4个子模块,可满足远程会诊全流程质量管理的功能需求。结论该质控系统创新了远程会诊信息化质量管理模式,在区域内实现了远程会诊全流程的信息化管理,取得了较好的质量管理成效,有效促进区域内远程会诊工作的推进和发展。 展开更多
关键词 远程会诊 B/s架构 质量控制 信息系统 设计 应用
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基于STM32的步进电机加减速轨迹规划算法
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作者 徐建明 徐金辉 《浙江工业大学学报》 CAS 北大核心 2024年第4期465-472,共8页
针对传统步进电机开环控制下加减速过程中柔性冲击大、失步和过冲等问题,结合STM32单片机提出了一种离散化的、带有电流调节的S曲线加减速控制算法。首先,通过多项式算法构建连续光滑的S曲线,根据矩频特性拟合转速和转矩的关系,联立转... 针对传统步进电机开环控制下加减速过程中柔性冲击大、失步和过冲等问题,结合STM32单片机提出了一种离散化的、带有电流调节的S曲线加减速控制算法。首先,通过多项式算法构建连续光滑的S曲线,根据矩频特性拟合转速和转矩的关系,联立转速和功率的关系,推导出电流计算方法;然后,对连续的S曲线进行等时间间隔采样,完成对S曲线的离散化;最后,在Keil平台进行算法代码编写,将编译后的工程文件下载到STM32中,通过步进电机的速度和位置跟踪实验验证了算法的有效性。 展开更多
关键词 步进电机 s曲线 加减速控制
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基于Super-Twisting滑模S面的无人机路径跟踪控制
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作者 张国兵 石上瑶 +2 位作者 李佳成 常哲 陈鹏云 《火力与指挥控制》 CSCD 北大核心 2024年第2期11-17,共7页
针对小型固定翼无人机在执行任务时跟踪精度低以及容易受外界风影响的问题,设计基于Super-Twisting滑模S面(STSM S-Plane)的路径跟踪控制器,同时采用内外双环控制模式。外环即速度环采用Super-Twisting滑模控制,内环即姿态环采用S面控... 针对小型固定翼无人机在执行任务时跟踪精度低以及容易受外界风影响的问题,设计基于Super-Twisting滑模S面(STSM S-Plane)的路径跟踪控制器,同时采用内外双环控制模式。外环即速度环采用Super-Twisting滑模控制,内环即姿态环采用S面控制。考虑到S面控制求导易导致积分爆炸的问题引入了二阶微分器,并对外界风组成进行建模研究。最后通过空间特殊曲线来验证所设计算法的控制性能。仿真结果表明,所设计的算法可以实现固定翼无人机对期望路径的精确跟踪,并具有良好的鲁棒性和抗干扰性能。 展开更多
关键词 固定翼无人机 super-Twisting滑模 s面控制 风干扰
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售货机升降系统S型速度控制策略
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作者 冯高明 邱文仙 金明磊 《电子科技》 2024年第5期54-61,共8页
在传统三闭环控制方式下,售货机升降接货系统易因启停过程中加速度突变产生冲击,导致系统运行不平稳。针对这一问题,文中对传统升降系统加减速控制策略进行改进,加入前馈和微分负反馈,提出一种S型速度曲线控制算法。根据路径规划判别条... 在传统三闭环控制方式下,售货机升降接货系统易因启停过程中加速度突变产生冲击,导致系统运行不平稳。针对这一问题,文中对传统升降系统加减速控制策略进行改进,加入前馈和微分负反馈,提出一种S型速度曲线控制算法。根据路径规划判别条件将S型速度曲线分为七段式、六段式和四段式3种,并给出各路径约束条件下的参数求解方法和具体执行流程。将该算法运用到升降控制系统中进行仿真和实际工况测试,实验结果表明,与传统三闭环控制相比,文中所提控制策略可以提高售货机升降系统运行的平稳性,减小冲击,使速度曲线更加柔和,并能够保持较好的跟踪性能。 展开更多
关键词 加减速控制 s型速度曲线 升降系统 加速度突变 冲击 售货机 控制策略 跟踪性能
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Capsule endoscopy and panendoscopy:A journey to the future of gastrointestinal endoscopy 被引量:1
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作者 Bruno Rosa JoséCotter 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1270-1279,共10页
In 2000,the small bowel capsule revolutionized the management of patients with small bowel disorders.Currently,the technological development achieved by the new models of double-headed endoscopic capsules,as miniaturi... In 2000,the small bowel capsule revolutionized the management of patients with small bowel disorders.Currently,the technological development achieved by the new models of double-headed endoscopic capsules,as miniaturized devices to evaluate the small bowel and colon[pan-intestinal capsule endoscopy(PCE)],makes this non-invasive procedure a disruptive concept for the management of patients with digestive disorders.This technology is expected to identify which patients will require conventional invasive endoscopic procedures(colonoscopy or balloon-assisted enteroscopy),based on the lesions detected by the capsule,i.e.,those with an indication for biopsies or endoscopic treatment.The use of PCE in patients with inflammatory bowel diseases,namely Crohn’s disease,as well as in patients with iron deficiency anaemia and/or overt gastrointestinal(GI)bleeding,after a non-diagnostic upper endoscopy(esophagogastroduodenoscopy),enables an effective,safe and comfortable way to identify patients with relevant lesions,who should undergo subsequent invasive endoscopic procedures.The recent development of magnetically controlled capsule endoscopy to evaluate the upper GI tract,is a further step towards the possibility of an entirely non-invasive assessment of all the segments of the digestive tract,from mouth-to-anus,meeting the expectations of the early developers of capsule endoscopy. 展开更多
关键词 Non-invasive endoscopy PANENDOsCOPY Magnetically controlled capsule endoscopy Crohn’s disease Digestive bleeding
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A gated recurrent unit model to predict Poisson’s ratio using deep learning 被引量:1
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作者 Fahd Saeed Alakbari Mysara Eissa Mohyaldinn +4 位作者 Mohammed Abdalla Ayoub Ibnelwaleed A.Hussein Ali Samer Muhsan Syahrir Ridha Abdullah Abduljabbar Salih 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期123-135,共13页
Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to spe... Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to specific data ranges with an average absolute percentage relative error(AAPRE)of more than 10%.The published gated recurrent unit(GRU)models do not consider trend analysis to show physical behaviors.In this study,we aim to develop a GRU model using trend analysis and three inputs for predicting n s based on a broad range of data,n s(value of 0.1627-0.4492),bulk formation density(RHOB)(0.315-2.994 g/mL),compressional time(DTc)(44.43-186.9 μs/ft),and shear time(DTs)(72.9-341.2μ s/ft).The GRU model was evaluated using different approaches,including statistical error an-alyses.The GRU model showed the proper trends,and the model data ranges were wider than previous ones.The GRU model has the largest correlation coefficient(R)of 0.967 and the lowest AAPRE,average percent relative error(APRE),root mean square error(RMSE),and standard deviation(SD)of 3.228%,1.054%,4.389,and 0.013,respectively,compared to other models.The GRU model has a high accuracy for the different datasets:training,validation,testing,and the whole datasets with R and AAPRE values were 0.981 and 2.601%,0.966 and 3.274%,0.967 and 3.228%,and 0.977 and 2.861%,respectively.The group error analyses of all inputs show that the GRU model has less than 5% AAPRE for all input ranges,which is superior to other models that have different AAPRE values of more than 10% at various ranges of inputs. 展开更多
关键词 static Poisson’s ratio Deep learning Gated recurrent unit(GRU) sand control Trend analysis Geomechanical properties
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固定翼UAV路径跟踪的全局稳定积分滑模S面控制
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作者 陈鹏云 张国兵 +2 位作者 李佳成 关通 石上瑶 《计算机工程与应用》 CSCD 北大核心 2024年第13期353-360,共8页
针对固定翼无人机的三维路径跟踪控制问题,设计了一种基于全局稳定积分滑模S面模型的内外环控制器。控制器外环采用全局稳定积分滑模控制,内环采用S面控制。设计控制器外环的全局稳定积分滑模控制律,并采用Lyapunov理论证明所设计控制... 针对固定翼无人机的三维路径跟踪控制问题,设计了一种基于全局稳定积分滑模S面模型的内外环控制器。控制器外环采用全局稳定积分滑模控制,内环采用S面控制。设计控制器外环的全局稳定积分滑模控制律,并采用Lyapunov理论证明所设计控制律的稳定性。对内环的指令信号设计S面控制器,考虑到S面控制器中求导的复杂性,引入二阶微分器,解决内环中导数存在积分爆炸的问题。半物理仿真试验结果表明,提出的控制器能精确跟踪期望路径,具有良好的控制性能和抗干扰性能。 展开更多
关键词 无人机 全局稳定 路径跟踪 运动控制 滑模控制 s面控制
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基于T-S MPC的车辆自适应巡航控制策略研究
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作者 刘晓龙 张蕾 +2 位作者 王清 李然然 安馨 《国外电子测量技术》 2024年第7期57-64,共8页
针对于汽车自适应巡航系统面对复杂工况时自适应性不强的问题,提出了一种基于T-S模糊变权重模型预测控制(Takagi-Sugeno fuzzy model predictive control,T-S MPC)的自适应巡航分层控制策略。首先上层控制器基于安全距离模型将自适应巡... 针对于汽车自适应巡航系统面对复杂工况时自适应性不强的问题,提出了一种基于T-S模糊变权重模型预测控制(Takagi-Sugeno fuzzy model predictive control,T-S MPC)的自适应巡航分层控制策略。首先上层控制器基于安全距离模型将自适应巡航系统划分为定速巡航模式、多目标优化控制的跟随模式和紧急制动模式;下层控制器基于车辆逆动力学模型,将上层控制器输出的期望加速度转变为节气门开度或制动压力;其次考虑到权重系数对控制精度的影响,建立基于T-S模糊控制的变权重模型预测控制器;最后搭建Carsim Simulink联合仿真平台,验证控制策略的准确性、适应性和跟踪响应速度。结果表明,在定速巡航工况时,T-S MPC控制方法跟踪响应时间为1.54 s,较PID和传统MPC控制跟踪响应快;在跟随和混合工况时,T-S MPC控制方法均方根误差为分别为0.3073、2.775,均低于PID、PID+LQR和传统MPC控制的均方根误差、并且自适应性好,有效提高了跟车性能与安全性。 展开更多
关键词 自适应巡航 分层控制 T-s MPC 控制策略
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基于S函数的调节阀粘滞特性检测方法
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作者 李世伟 尚群立 《高技术通讯》 CAS 北大核心 2024年第4期406-412,共7页
调节阀粘滞特性引起的振荡是工业控制回路性能恶化的最常见来源。目前虽然已有许多检测调节阀粘滞特性的方法,但这些方法的复杂性或存在的缺陷限制着其在实际工况中的具体应用。本文提出了一种检测过程控制回路中调节阀粘滞故障的新方... 调节阀粘滞特性引起的振荡是工业控制回路性能恶化的最常见来源。目前虽然已有许多检测调节阀粘滞特性的方法,但这些方法的复杂性或存在的缺陷限制着其在实际工况中的具体应用。本文提出了一种检测过程控制回路中调节阀粘滞故障的新方法。该方法将控制器输出(OP)和过程变量(PV)的变化(ΔPV)在相平面图中所构成变化趋势与标准S函数进行对比,根据实际函数趋势与标准S函数间的差异计算相关系数,通过相关系数的数值具体得出调节阀中是否存在粘滞特性。仿真实例和实际工业数据分析实验验证了提出方法的有效性。 展开更多
关键词 调节阀 相关系数 s函数 粘滞检测
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基于自适应S面算法的小型ROV艏向和深度运动控制研究
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作者 李国虎 周焕银 《机床与液压》 北大核心 2024年第8期34-38,共5页
带缆遥控水下机器人(ROV)系统艏向与深度运动具有强非线性和运行环境不确定性等特点。针对ROV的运动特点,构建运动控制模型并进行化简,通过构建自适应S面控制法对艏向与深度进行控制,并利用Lyapunov的稳定性判据证明该控制法的稳定性,... 带缆遥控水下机器人(ROV)系统艏向与深度运动具有强非线性和运行环境不确定性等特点。针对ROV的运动特点,构建运动控制模型并进行化简,通过构建自适应S面控制法对艏向与深度进行控制,并利用Lyapunov的稳定性判据证明该控制法的稳定性,通过仿真验证了该控制法具有良好的稳定性和控制品质。同时,与S面控制法相比,自适应S面控制具有更好的动态性能与静态性能,调节速度快、稳定性强,能够准确控制ROV运动。 展开更多
关键词 ROV 自适应s面控制 艏向控制 深度控制
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Real-Time Co-optimization of Gear Shifting and Engine Torque for Predictive Cruise Control of Heavy-Duty Trucks
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作者 Hongqing Chu Xiaoxiang Na +4 位作者 Huan Liu Yuhai Wang Zhuo Yang Lin Zhang Hong Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期294-317,共24页
Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a rea... Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a real-time implementable PCC,which simultaneously optimizes engine torque and gear shifting,is proposed for heavy-duty trucks.To minimize fuel consumption,the problem of the PCC is formulated as a nonlinear model predictive control(MPC),in which the upcoming road elevation information is used.Finding the solution of the nonlinear MPC is time consuming;thus,a real-time implementable solver is developed based on Pontryagin’s maximum principle and indirect shooting method.Dynamic programming(DP)algorithm,as a global optimization algorithm,is used as a performance benchmark for the proposed solver.Simulation,hardware-in-the-loop and real-truck experiments are conducted to verify the performance of the proposed controller.The results demonstrate that the MPC-based solution performs nearly as well as the DP-based solution,with less than 1%deviation for testing roads.Moreover,the proposed co-optimization controller is implementable in a real-truck,and the proposed MPC-based PCC algorithm achieves a fuel-saving rate of 7.9%without compromising the truck’s travel time. 展开更多
关键词 Heavy-duty truck Predictive cruise control Model predictive control Pontryagin’s maximum principle Real-truck implementation
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Enhancing Mild Cognitive Impairment Detection through Efficient Magnetic Resonance Image Analysis
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作者 Atif Mehmood Zhonglong Zheng +7 位作者 Rizwan Khan Ahmad Al Smadi Farah Shahid Shahid Iqbal Mutasem K.Alsmadi Yazeed Yasin Ghadi Syed Aziz Shah Mostafa M.Ibrahim 《Computers, Materials & Continua》 SCIE EI 2024年第8期2081-2098,共18页
Neuroimaging has emerged over the last few decades as a crucial tool in diagnosing Alzheimer’s disease(AD).Mild cognitive impairment(MCI)is a condition that falls between the spectrum of normal cognitive function and... Neuroimaging has emerged over the last few decades as a crucial tool in diagnosing Alzheimer’s disease(AD).Mild cognitive impairment(MCI)is a condition that falls between the spectrum of normal cognitive function and AD.However,previous studies have mainly used handcrafted features to classify MCI,AD,and normal control(NC)individuals.This paper focuses on using gray matter(GM)scans obtained through magnetic resonance imaging(MRI)for the diagnosis of individuals with MCI,AD,and NC.To improve classification performance,we developed two transfer learning strategies with data augmentation(i.e.,shear range,rotation,zoom range,channel shift).The first approach is a deep Siamese network(DSN),and the second approach involves using a cross-domain strategy with customized VGG-16.We performed experiments on the Alzheimer’s Disease Neuroimaging Initiative(ADNI)dataset to evaluate the performance of our proposed models.Our experimental results demonstrate superior performance in classifying the three binary classification tasks:NC vs.AD,NC vs.MCI,and MCI vs.AD.Specifically,we achieved a classification accuracy of 97.68%,94.25%,and 92.18%for the three cases,respectively.Our study proposes two transfer learning strategies with data augmentation to accurately diagnose MCI,AD,and normal control individuals using GM scans.Our findings provide promising results for future research and clinical applications in the early detection and diagnosis of AD. 展开更多
关键词 Alzheimer’s disease mild cognitive impairment normal control transfer learning CLAssIFICATION augmentation
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Exploring Variability in Sea Level at a Tide Gauge Station through Control Charts
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作者 H.Bâkiİz 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期11-18,共8页
Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic ... Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic oscillations,and random disturbances.Among them,the non-stationary nature of the random sea level variations of known or unknown origin at coastal regions has been long recognized by the sea level community.This study proposes the analyses of subgroups of random residual statistics of a rigorously formulated kinematic model solution of tide gauge variations using X-bar and S control charts.The approach is demonstrated using Key West,Florida tide gauge records.The mean and standard errors of 5-year-long subgroups of the residuals revealed that sea level changes at this location have been progressively intensifying from 1913 to the present.Increasing oscillations in sea level at this locality may be attributed partly to the thermal expansion of seawater with increasing temperatures causing larger buoyancy-related sea level fluctuations as well as the intensification of atmospheric events including wind patterns and the impact of changes in inverted barometer effects that will alter coastal risk assessments for the future. 展开更多
关键词 Climate change sea level variance X-bar s control charts
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Antibody Titer of Newcastle Disease in Vaccinated and Non-vaccinated Local Chicken of Cambodia
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作者 Sokha Thim Solida Keo +4 位作者 Kannan Dim Kroesna Kang Sath Keo Vutey Venn Kouch Theng 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第2期80-85,共6页
The experiment was conducted at Veterinary Research Station of Faculty of Veterinary Medicine,Royal University of Agriculture.The experimental period lasted 60 days,starting from October 1st to November 30th 2022.CRD(... The experiment was conducted at Veterinary Research Station of Faculty of Veterinary Medicine,Royal University of Agriculture.The experimental period lasted 60 days,starting from October 1st to November 30th 2022.CRD(Completely Randomized Design)was used with 2 treatments/groups,vaccination group and non-vaccination group“control”,and 6 replications.The vaccination groups received two times of vaccination by dropping into the ocular at 7 days and 21 days.Meanwhile,blood samples were collected 3 times to detect the antibody level of ND(Newcastle Disease)and contained 21 days old,35 days old and 49 days old chicks.The ELISA(Enzyme-Linked Immunosorbent Assay)was performed to detect the antibody of those 2 groups.The result of finding showed that the S/P(Sample to Positive)ratio of control at 21 days,was very low,even in 3rd quartile,which was below the threshold.However,the vaccination group was relatively high,even in 1st quartile,which was higher than the threshold.At 35 days,S/P ratio of control group was still very low,but a bit higher than at 21 days.Meanwhile,the vaccination group was still high,even in 1st quartile,and two-time higher than at 21 days,but an increasing number of samples developed less antibody than threshold,accounting for 12.22%.At 49 days,the control group was still very low,even in 3rd quartile,but a bit higher than at 21 days and 35 days,and was close to the threshold.The vaccination group was still relatively high,even in 1st quartile but lower than three times comparing to 35 days.However,in this age,the number of chickens that developed antibody seemed to be increased in the control group,vice versa for vaccination group.The average S/P ratio was different significant(p<0.001),where vaccination had higher S/P ratio than control.It was similar finding for log-titer,the vaccination had higher figure(p<0.001).The risk of infection of ND was higher in control group,but it will reduce by increasing the age of chicken,while vaccination group was decreased by increasing age,especially at 49 days and we need to consider another vaccination to get full protection. 展开更多
关键词 ANTIBODY VACCINATION CONTROL ND s/P ratio
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Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation
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作者 Chang Yang Yong-bo Tie +3 位作者 Xian-zheng Zhang Yan-feng Zhang Zhi-jie Ning Zong-liang Li 《China Geology》 CAS CSCD 2024年第2期248-263,共16页
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff... Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events. 展开更多
关键词 Landslide Debris flow Hazard assessment Numerical simulation OpenLIsEM Prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully sichuan province Geological hazards survey engineering
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基于S形速度曲线的键合头运动控制系统研究与分析
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作者 高岳 《电子工业专用设备》 2024年第2期52-57,共6页
根据用户工艺需求,针对全自动芯片键合设备的运动控制模块以及键合头子模块开展需求分析,结合典型试验,设计出基于S形速度曲线的键合头运动控制系统,根据S形速度曲线重新规划了键合头的运动轨迹,使其对芯片键合周期缩短的同时也保证了... 根据用户工艺需求,针对全自动芯片键合设备的运动控制模块以及键合头子模块开展需求分析,结合典型试验,设计出基于S形速度曲线的键合头运动控制系统,根据S形速度曲线重新规划了键合头的运动轨迹,使其对芯片键合周期缩短的同时也保证了键合精度。 展开更多
关键词 运动控制模块 键合头 s形速度曲线
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“Λ”型凸台对低隔道亚声速S弯进气道的流场控制研究
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作者 唐小松 金志光 《机械制造与自动化》 2024年第4期259-263,共5页
针对某无人机进气系统低隔道亚声速S弯进气道出口流场畸变较大的问题,研究一种利用隔道内置“Λ”型凸台生成反向涡抑制出口畸变的流场控制手段。通过数值仿真分析“Λ”型凸台结构对抑制流场畸变的作用机制,给出不同来流条件下凸台结... 针对某无人机进气系统低隔道亚声速S弯进气道出口流场畸变较大的问题,研究一种利用隔道内置“Λ”型凸台生成反向涡抑制出口畸变的流场控制手段。通过数值仿真分析“Λ”型凸台结构对抑制流场畸变的作用机制,给出不同来流条件下凸台结构参数对进气道出口总压恢复系数和流场畸变的影响规律。研究表明:畸变控制效果与凸台几何尺寸密切相关,合理设计的凸台对出口畸变抑制效果明显。 展开更多
关键词 无人机 亚声速进气道 s弯进气道 流场畸变 流场控制 数值仿真
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T-S模糊系统的动态自触发有限时间H_(∞)控制
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作者 刘晓迪 闻继伟 《仪表技术与传感器》 CSCD 北大核心 2024年第8期99-108,共10页
文中研究一类不确定Takagi-Sugeno(T-S)模糊系统的自触发有限时间H_(∞)控制。首先,提出动态自触发方案,构造触发参数的动力学方程,从而使自触发机制能依据触发时刻状态自适应地调整触发参数;同时,基于当前触发时刻的系统状态实时计算... 文中研究一类不确定Takagi-Sugeno(T-S)模糊系统的自触发有限时间H_(∞)控制。首先,提出动态自触发方案,构造触发参数的动力学方程,从而使自触发机制能依据触发时刻状态自适应地调整触发参数;同时,基于当前触发时刻的系统状态实时计算触发间隔,预测下一个触发时刻。相较于T-S模糊系统的静态自触发方案,文中所提的动态自触发方案能进一步降低触发频率,节约计算资源。其次,基于有限时间稳定理论,设置系统状态运动轨迹的次临界界限;结合状态轨迹与次临界界限的相对位置关系和动态自触发方案,分析系统的H_(∞)性能;此外,设计依赖模糊规则的H_(∞)状态反馈控制律,保证T-S模糊系统的动力学行为有限时间有界。最后,给出实例仿真验证文中方法的可行性。 展开更多
关键词 有限时间有界 动态自触发控制 鲁棒H_(∞)控制 T-s模糊系统
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S Zorb装置再生器进料罐排气线调节球阀国产化改造研究
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作者 秦鲜友 《兰州石化职业技术大学学报》 2024年第2期10-15,共6页
S Zorb装置再生器进料罐排气线调节球阀通过调节进料罐压力来控制装置吸附剂的循环速率,直接影响装置的催化剂再生,对装置的正常生产至关重要。由于介质流速快、吸附剂硬度高、阀门正常开度小等原因,冲刷很严重,使用寿命短,给装置安稳... S Zorb装置再生器进料罐排气线调节球阀通过调节进料罐压力来控制装置吸附剂的循环速率,直接影响装置的催化剂再生,对装置的正常生产至关重要。由于介质流速快、吸附剂硬度高、阀门正常开度小等原因,冲刷很严重,使用寿命短,给装置安稳生产带来了很大的困扰。通过CFD(Computational Fluid Dynamics,即计算流体动力学分析)分析,对该阀进行国产化改造,提升了调节性能和使用寿命,大幅降低了购置成本,在控制阀国产化方面,具有较高的推广应用价值。 展开更多
关键词 s Zorb 控制阀 CFD 国产化改造
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