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基于改进DNN的F‐P滤波器温度误差补偿方法
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作者 肖蔚然 韩晓冉 +3 位作者 张荣达 刘卜玮 刘鹏鲲 姚国珍 《半导体光电》 北大核心 2026年第1期186-192,共7页
为解决FBG传感系统中F-P滤波器的温度误差问题,文章提出一种基于改进DNN的F-P滤波器温度误差补偿方法。该方法在传统DNN模型的基础上增加了BN层、Dropout层、注意力机制层和残差连接层,提高了DNN模型的性能。利用改进后的DNN模型预测F-... 为解决FBG传感系统中F-P滤波器的温度误差问题,文章提出一种基于改进DNN的F-P滤波器温度误差补偿方法。该方法在传统DNN模型的基础上增加了BN层、Dropout层、注意力机制层和残差连接层,提高了DNN模型的性能。利用改进后的DNN模型预测F-P滤波器在不同温度和电压时的波长漂移,再将不同温度下F-P滤波器的波长折算到某一固定温度时的波长,从而消除了温度变化带来的误差。通过搭建实验系统,对所提方法进行实验验证,并与LSTM和LSTM+CNN误差补偿模型预测结果进行对比。实验结果表明,误差补偿后的波长标准差最大为4.7 pm,偏离平均值的最大波动为13.3 pm,相比补偿前,标准差降低了99.96%,最大波动降低了99.93%。利用所提方法可在不添加额外硬件的基础上显著提高FBG传感的精度,减小系统的复杂性和成本。 展开更多
关键词 DNN 误差补偿 f-p滤波器 波长解调 fBG传感
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基于P-ROQR+Q-FRC的模块化多电平变流器环流抑制策略
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作者 张路 李可礼 +1 位作者 智鹏飞 尤越 《电子测量技术》 北大核心 2026年第2期26-36,共11页
模块化多电平变流器(MMC)的拓扑结构适用于高压直流输电(HVDC),在运行时内部易产生环流导致桥臂电流畸变,增加系统功率损耗并降低稳定性。针对P-ROQR控制器控制精度受限且鲁棒性欠佳等问题,本文提出基于P-ROQR+Q-FRC控制器的环流抑制策... 模块化多电平变流器(MMC)的拓扑结构适用于高压直流输电(HVDC),在运行时内部易产生环流导致桥臂电流畸变,增加系统功率损耗并降低稳定性。针对P-ROQR控制器控制精度受限且鲁棒性欠佳等问题,本文提出基于P-ROQR+Q-FRC控制器的环流抑制策略,在P-ROQR控制器基础上引入Q-FRC控制器二、四次环流分量得到有效抑制且实现简单。为验证方法有效性,在相同条件下,分别在稳态、直流电压降落、直流电压波动、三相不平衡工况下进行MMC-HVDC仿真实验。结果表明,基于P-ROQR+Q-FRC环流抑制器的MMC动态性能和环流抑制能力均优于P-ROQR环流抑制器,环流波动范围相比降低57.14%,子模块电容电压波动范围相比降低7.5%,更适用于MMC变流器。 展开更多
关键词 环流抑制 模块化多电平变流器 p-ROQR%pLUS%Q-fRC控制器
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Average Run Length in TEWMA Control Charts:Analytical Solutions for AR(p)Processes and Real Data Applications
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作者 Sirawit Makaew Yupaporn Areepong Saowanit Sukparungsee 《Computer Modeling in Engineering & Sciences》 2025年第5期1617-1634,共18页
This study aims to examine the explicit solution for calculating the Average Run Length(ARL)on the triple exponentially weighted moving average(TEWMA)control chart applied to autoregressive model(AR(p)),where AR(p)is ... This study aims to examine the explicit solution for calculating the Average Run Length(ARL)on the triple exponentially weighted moving average(TEWMA)control chart applied to autoregressive model(AR(p)),where AR(p)is an autoregressive model of order p,representing a time series with dependencies on its p previous values.Additionally,the study evaluates the accuracy of both explicit and numerical integral equation(NIE)solutions for AR(p)using the TEWMA control chart,focusing on the absolute percentage relative error.The results indicate that the explicit and approximate solutions are in close agreement.Furthermore,the study investigates the performance of exponentially weighted moving average(EWMA)and TEWMA control charts in detecting changes in the process,using the relative mean index(RMI)as a measure.The findings demonstrate that the TEWMA control chart outperforms the EWMA control chart in detecting process changes,especially when the value ofλis sufficiently large.In addition,an analysis using historical data from the SET index between January 2024 and May 2024 and historical data of global annual plastic production,the results of both data sets also emphasize the superior performance of the TEWMA control chart. 展开更多
关键词 EWMA control chart TEWMA control charts average run length shift detection explicit formula fredholm integral equation Banach’s fixed-point theorem AR(p)process
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LQR Discrete Time Control of a Buck Converter Using a Non-Minimal State Space Representation
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作者 Richard Tymerski 《Journal of Power and Energy Engineering》 2025年第1期32-46,共15页
This paper presents an advanced control strategy for DC-DC buck converters utilizing Non-Minimal State Space (NMSS) representation combined with Proportional-Integral-Plus (PIP) control, optimized through Linear Quadr... This paper presents an advanced control strategy for DC-DC buck converters utilizing Non-Minimal State Space (NMSS) representation combined with Proportional-Integral-Plus (PIP) control, optimized through Linear Quadratic Regulator (LQR) design. The proposed approach leverages NMSS to eliminate the need for state observers, enhancing robustness against model mismatch and improving overall system performance. The PIP controller extends traditional PI control by incorporating additional dynamic feedback. Experimental results demonstrate that the NMSS-PIP-LQR controlled buck converter achieves excellent dynamic performance. The design procedure is fully documented, and microcontroller implementation issues are discussed. 展开更多
关键词 DC-DC Buck Converter Non-Minimal State Space (NMSS) proportional-Integral-plus (pIp) control Linear Quadratic Regulator (LQR) f28069M Microcontroller
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一种应用于卫星通信的双频双圆极化Fabry-Perot谐振腔天线
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作者 罗伟 罗柳 +2 位作者 何鑫 王小雪 张红升 《电波科学学报》 北大核心 2025年第6期1043-1051,共9页
为探索更高性能的卫星通信天线,提出了一种基于法布里-珀罗(Fabry-Perot,F-P)谐振腔的双频双圆极化天线。该天线通过加载两种双层部分反射表面(partial reflective surface,PRS)构建双谐振腔,使得来自馈源的电磁波在双腔体内多次反射并... 为探索更高性能的卫星通信天线,提出了一种基于法布里-珀罗(Fabry-Perot,F-P)谐振腔的双频双圆极化天线。该天线通过加载两种双层部分反射表面(partial reflective surface,PRS)构建双谐振腔,使得来自馈源的电磁波在双腔体内多次反射并同相叠加,从而实现高增益圆极化辐射。所设计的PRS基于电磁超表面技术分别具有高通和低通功能,使得天线获得了双频特性。采用2×2的切角微带贴片天线阵列作为馈源,并基于顺序旋转馈电技术改善了馈源轴比特性。天线样机的测试结果表明,C波段和Ku波段的工作带宽分别为8.03%和4.14%,峰值增益为14.78 dBi和14.52 dBi。该天线性能满足频分双工卫星通信系统要求,适用于未来高速卫星互联网的地面设备。 展开更多
关键词 卫星通信 法布里-珀罗(f-p)谐振腔天线 电磁超表面 双频双圆极化 顺序旋转馈电技术
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miR-204-5p通过靶向结合转录因子E2F1下调RRM2的表达以抑制乳腺癌细胞增殖并影响细胞周期分布
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作者 褚旭 李翔 +1 位作者 赵浩 邹燕 《四川医学》 2025年第7期773-780,共8页
目的探讨miR-204-5p调控乳腺癌细胞恶性表型的具体机制,为乳腺癌靶向药物的开发以及新治疗靶标的挖掘提供新思路。方法qRT-PCR检测乳腺癌细胞中miR-204-5p、E2F1和RRM2的表达水平。CCK-8和克隆形成实验检测乳腺癌细胞增殖能力,流式细胞... 目的探讨miR-204-5p调控乳腺癌细胞恶性表型的具体机制,为乳腺癌靶向药物的开发以及新治疗靶标的挖掘提供新思路。方法qRT-PCR检测乳腺癌细胞中miR-204-5p、E2F1和RRM2的表达水平。CCK-8和克隆形成实验检测乳腺癌细胞增殖能力,流式细胞术检测细胞周期变化,生信预测和双荧光素酶活性检测miR-204-5p和E2F1,E2F1和RRM2的结合关系。结果双荧光素酶活性检测结果表明miR-204-5p靶向结合E2F1抑制E2F1的表达,转录因子E2F1能够通过靶向结合关系促进RRM2的表达。回复实验结果表明miR-204-5p可以通过结合转录因子E2F1抑制乳腺癌细胞的增殖并诱导细胞G1期阻滞,E2F1可以通过结合RRM2促进乳腺癌细胞增殖抑制细胞G1期阻滞。结论miR-204-5p可以通过结合转录因子E2F1抑制RRM2的表达,从而诱导乳腺癌细胞停滞于G1期,抑制乳腺癌细胞的增殖,这为乳腺癌靶向药物的开发以及新治疗靶标的挖掘提供了新的思路。 展开更多
关键词 miR-204-5p 乳腺癌 E2f1 RRM2 增殖 G1期阻滞
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Control Efficacy of Validamycin A·(0.2 Billion Spores/ml) Paenibacillus polymyxa DN-1 3% AS for Rice Sheath Blight
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作者 胡飞 苏卫华 +4 位作者 李昌春 周子燕 胡本进 徐丽娜 郑进国 《Agricultural Science & Technology》 CAS 2016年第11期2615-2618,共4页
With validamycin A.(0.2 billion spores/ml) Paenibacillus polymyxa DN-1 3% AS as the test agent, the effects of different dosage and different application time on the control efficacy for' rich sheath blight were in... With validamycin A.(0.2 billion spores/ml) Paenibacillus polymyxa DN-1 3% AS as the test agent, the effects of different dosage and different application time on the control efficacy for' rich sheath blight were investigated. The results of two- year test showed that when the application amount was in the range of 45-90 g.a.i/ hm^2, the field efficacy of validamycin A-(0.2 billion spores/ml) P. polymyxa DN-1 3% AS in the initial infection stage of rich sheath blight (Le., the diseased plant rate was below 5%) reached 80.38%-89.06%, and that in the peak infection stage (i.e., the diseased plant rate was higher than 10%) reached only 41.12%-53.26%. The field efficacy of validamycin A.(0.2 billion spores/ml) P. polymyxa DN-1 3% AS at the early onset of rich sheath blight was significantly better than that at the onset, so that the application time of validamycin A .(0.2 billion spores/ml) P. polymyxa DN-1 3% AS should be appropriately brought forward in the prevention and control of rice sheath blight. 展开更多
关键词 Validamycin A-(0.2 billion spores/roll p. polymyxa DN-1 3% AS Rice sheath blight Initial infection stage peak infection stage control efficacy
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SiC_(p)/Cu基复合材料性能提升与界面调控优化的研究进展
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作者 张云龙 王俊青 +5 位作者 张唯一 王伟娥 任晓雪 李成海 翟梓棫 刘德宝 《聊城大学学报(自然科学版)》 2026年第1期75-83,共9页
随着高端制造、电子封装与热管理等领域对材料综合性能的持续提升要求,传统铜及其合金材料在强度、耐磨性与导电导热性能方面逐渐显现出瓶颈。碳化硅颗粒增强铜基复合材料(SiC_(p)/Cu)因其优异的力学、电学与热物理性能,受到广泛关注。... 随着高端制造、电子封装与热管理等领域对材料综合性能的持续提升要求,传统铜及其合金材料在强度、耐磨性与导电导热性能方面逐渐显现出瓶颈。碳化硅颗粒增强铜基复合材料(SiC_(p)/Cu)因其优异的力学、电学与热物理性能,受到广泛关注。围绕SiC颗粒粒径、含量及分布等组成设计参数的优化,系统综述了SiC_(p)/Cu基复合材料在耐磨、导电、导热和耐蚀等方面的性能提升机制,探讨了Cu基体微合金化与SiC颗粒表面修饰的界面调控策略以及多相协同增强的设计理念,将为高性能SiC_(p)/Cu基复合材料的设计开发提供参考依据。 展开更多
关键词 SiC_(p)/Cu基复合材料 界面调控 性能提升机制 材料设计优化
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利用免疫信息学方法设计猪产肠毒素大肠杆菌987P-F18蛋白的多表位疫苗
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作者 徐佳微 李铁山 +6 位作者 李昕 刘意 赵格 曲志娜 宋时萍 张喜悦 王君玮 《华北农学报》 北大核心 2025年第S1期323-328,共6页
利用免疫信息学方法设计一种预防猪大肠杆菌感染的多表位疫苗,阻断产肠毒素大肠杆菌(ETEC)菌株与仔猪肠道上皮细胞的黏附和定植以预防仔猪腹泻。通过免疫信息学工具对ETEC的黏附素987P和F18的B细胞抗原表位、Th细胞表位、CTL细胞表位进... 利用免疫信息学方法设计一种预防猪大肠杆菌感染的多表位疫苗,阻断产肠毒素大肠杆菌(ETEC)菌株与仔猪肠道上皮细胞的黏附和定植以预防仔猪腹泻。通过免疫信息学工具对ETEC的黏附素987P和F18的B细胞抗原表位、Th细胞表位、CTL细胞表位进行预测,筛选出优势表位。将优势表位按照3种不同表位排列顺序通过Linker连接成多表位疫苗,并对其抗原性、致敏性以及三级结构进行预测。结果显示,共筛选出7个优势表位。抗原性试验显示,融合多肽Ⅰ的抗原性为1.0692;融合多肽Ⅱ的抗原性为1.0892;融合多肽Ⅲ的抗原性为1.0507,都具有良好的抗原性。过敏性试验结果显示,融合多肽Ⅰ、Ⅱ、Ⅲ都无过敏性。三级结构结果显示,3种融合多肽结构表位的暴露性都较好,容易和抗体结合,并且在蛋白分子的构象中都符合要求。此外,还根据不同的规则,排列了3种氨基酸序列,并按照乳酸菌密码子嗜好性,反向翻译为核苷酸序列,插入至pET28a质粒中,分别获得了pET28a-9F1、pET28a-9F2和pET28a-9F3质粒。 展开更多
关键词 大肠杆菌 多表位疫苗 免疫信息学 987p f18
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数字化F-P前端的仿真验证
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作者 史会贤 马琳 许骏 《电子技术应用》 2025年第1期94-102,共9页
提出一种基于差分电容原理的新型数字化F-P滤波器电路控制系统,并基于FPGA对该系统进行了理论分析以及硬件验证,验证结果表明该系统避免了现有F-P滤光器模拟电路控制系统的系统时间稳定性差的问题,具有极高的抗干扰能力,为高稳定无漂移... 提出一种基于差分电容原理的新型数字化F-P滤波器电路控制系统,并基于FPGA对该系统进行了理论分析以及硬件验证,验证结果表明该系统避免了现有F-P滤光器模拟电路控制系统的系统时间稳定性差的问题,具有极高的抗干扰能力,为高稳定无漂移的F-P控制系统提供了新思路。 展开更多
关键词 数字化 f-p 伺服控制 电容测距
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I/F起动结合改进滑模观测器的PMSM全速域控制 被引量:1
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作者 张旭梅 谢佳莉 黄安贻 《安徽大学学报(自然科学版)》 北大核心 2025年第3期60-71,共12页
为提高永磁同步电机全速域无传感器控制性能,该文研究了永磁同步电机无传感器全速域控制策略和算法,提出了一种I/F起动结合改进滑模观测器的控制策略,即在零低速域采用I/F起动控制,在中高速域采用改进滑模观测器,通过电流切换法来实现... 为提高永磁同步电机全速域无传感器控制性能,该文研究了永磁同步电机无传感器全速域控制策略和算法,提出了一种I/F起动结合改进滑模观测器的控制策略,即在零低速域采用I/F起动控制,在中高速域采用改进滑模观测器,通过电流切换法来实现两种不同速域控制方式的切换.针对所提控制策略的有效性,该文还开展了仿真分析和实验研究,结果表明,该文所提电流切换法能有效实现不同速域转速的平稳切换,并且中高速域的转速控制精度亦得到显著提高. 展开更多
关键词 永磁同步电机 无传感器控制 I/f起动 改进滑模观测器
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面阵对称翻转变换用于F-P微小角度测量系统 被引量:1
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作者 吴晨光 沈小燕 周世南 《中国测试》 北大核心 2025年第1期111-118,共8页
法布里珀罗(F-P)标准具应用于位移和角度测量时,其干涉成像同心圆环圆心坐标的准确计算对测量结果具有关键影响。针对面阵CCD传感器上干涉成像同心圆环在移动时存在的误差,利用干涉成像同心圆环有效信息,提出一种面阵像元正反细分的对... 法布里珀罗(F-P)标准具应用于位移和角度测量时,其干涉成像同心圆环圆心坐标的准确计算对测量结果具有关键影响。针对面阵CCD传感器上干涉成像同心圆环在移动时存在的误差,利用干涉成像同心圆环有效信息,提出一种面阵像元正反细分的对称翻转算法,在理论分析的基础上进行算法和实验验证。将该算法应用于F-P微小角度测量系统并进行比对实验研究。实验结果表明该算法可将圆心坐标标准差减小至0.0028个像素单位;在±150″测量范围内,F-P微小角度测量系统的测量值与ELCOMAT HR自准直仪两者的示值误差不大于0.38″,经拟合修正后两者示值误差不大于0.06″,测量准确度得到有效提高。 展开更多
关键词 f-p标准具 对称翻转变换 像元平滑细分 圆心坐标计算 微小角度测量
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Moving fast, thinking fast:The relations of physical activity levels and bouts to neuroelectric indices of inhibitory control in preadolescents 被引量:3
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作者 Dominika M.Pindus Eric S.Drollette +9 位作者 Lauren B.Raine Shih-Chun Kao Naiman Khan Daniel R.Westfall Morgan Hamill Rebecca Shorin Emily Calobrisi Dinesh John Arthur F.Kramer Charles H.Hillman 《Journal of Sport and Health Science》 SCIE 2019年第4期301-314,共14页
Background:Structured vigorous physical activity(VPA)can improve cognitive control in children,but studies relating daily physical activity(PA)to cognitive control have yielded conflicting findings.While objectively m... Background:Structured vigorous physical activity(VPA)can improve cognitive control in children,but studies relating daily physical activity(PA)to cognitive control have yielded conflicting findings.While objectively measured daily PA summarizes all occurrences of PA within a registered period,a minimum duration of continuous PA is required for registration of a PA bout.Because brief bouts of high-intensity PA can account for a large proportion of children’s daily activity-related energy expenditure,this study assessed whether daily and bouted VPA were selectively related to cognitive control in preadolescents relative to other PA intensities.Methods:A total of 75 children between the ages of 8 and 10 years(49%girls)wore an ActiGraph wGT 3 X+on the hip for 7 days.The acceleration signal from the vertical axis was summarized over 1 s,5 s,and 15 s epochs.Daily and boutecd modercate PA,moderate-to-vigorous PA,and VPA were measured.PA bouts were expressed as the frequency and time spent in 2 different continuous PA bouts,one lasting≥10 s and the other lasting≥30 s at a given intensity.Inhibitory control was assessed using behavioral responses to a modified flanker task(mean reaction time(RTmean)and accuracy).Attentional resource allocation and co gnitive processing speed were measured using the amplitude and latency of the P3 component of event-related brain potentials,respectively.Associations between PA,behavioral indices of inhibitory control,P3 amplitude,and latency were assessed using hierarchical regression models.Results:Daily VPA was not related to RTmean or accuracy on either congruent or incongruent trials.In contrast,more time spent in VPA bouts lasting≥30 s predicted shorter P3 latency across epochs and flanker congruencies(allβ≤-0.24,all p≤0.04).The associations between shorter P3 latency and the time spent in moderate-to-vigorous PA bouts lasting≥30 s were less consistent and largely limited to congruent trials(congruent:β(-0.3 1,-0.34)).No significant associations were observed upon correction for false discovery rate.Conclusion:The pattern of uncorrected associations aligns with the dose-response literature and suggests that brief VPA bouts may yield the greatest benefits to cognitive processing speed in preadolescents.Future studies using measures of brain structure and function are needed to understand the mechanisms linking bouted VPA to neurocognitive function during childhood. 展开更多
关键词 ACCELEROMETRY Bouts Children ERpS INHIBITORY control p3 physical activity
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HPV感染宫颈癌根治术患者组织FOXF2、ANGPTL4、FOXP3表达与病理特征及复发的关联 被引量:1
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作者 曾海荣 黄丹 +1 位作者 张建军 华海琴 《中华医院感染学杂志》 北大核心 2025年第6期890-894,共5页
目的探究人乳头瘤病毒(HPV)感染宫颈癌根治术患者组织叉头框转录因子(FOX)F2、血管生成素样蛋白4(ANGPTL4)、FOXP3表达与病理特征及复发的关联。方法简单随机化法选取儋州市人民医院2018年11月-2021年7月收治的69例HPV感染宫颈癌根治术... 目的探究人乳头瘤病毒(HPV)感染宫颈癌根治术患者组织叉头框转录因子(FOX)F2、血管生成素样蛋白4(ANGPTL4)、FOXP3表达与病理特征及复发的关联。方法简单随机化法选取儋州市人民医院2018年11月-2021年7月收治的69例HPV感染宫颈癌根治术患者为宫颈癌组及72例同期宫颈上皮内瘤变患者为宫颈上皮内瘤变组。根据宫颈癌组预后情况分为复发组25例和未复发组44例。比较各组组织FOXF2、ANGPTL4和FOXP3水平;比较FOXF2、ANGPTL4和FOXP3在宫颈癌组不同临床病理特征中表达及不同预后患者病理特征;分析三指标对HPV感染宫颈癌根治术后复发的诊断价值。结果宫颈癌组、宫颈上皮内瘤变组组织FOXF2 mRNA、ANGPTL4 mRNA和FOXP3 mRNA水平比较,差异有统计学意义(P<0.05);不同国际妇产科协会(FIGO)分期、淋巴结转移、浸润深度的HPV感染宫颈癌根治术患者FOXF2 mRNA、ANGPTL4 mRNA和FOXP3 mRNA水平比较,差异有统计学意义(P<0.05);复发组和未复发组在FIGO分期、淋巴结转移、浸润深度差异及FOXF2 mRNA、ANGPTL4 mRNA和FOXP3 mRNA水平比较,差异有统计学意义(P<0.05)。FOXF2 mRNA、ANGPTL4 mRNA和FOXP3 mRNA联合检测诊断HPV感染宫颈癌根治术后复发的曲线下面积(AUC)值高于单一检测(P<0.05)。结论HPV感染宫颈癌根治术患者组织FOXF2 mRNA、ANGPTL4 mRNA和FOXP3 mRNA异常表达,三指标与FIGO分期、淋巴结转移、浸润深度有关,且三指标联合检测对其术后复发诊断价值高。 展开更多
关键词 宫颈癌 人乳头瘤病毒 复发 叉头框转录因子f2 血管生成素样蛋白4 叉头框转录因子p3 受试者工作特征曲线 诊断价值
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Time-delay Compensation Method for Networked Control System Based on Time-delay Prediction and Implicit PIGPC 被引量:1
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作者 Zhong-Da Tian Xian-Wen Gao +1 位作者 Bi-Lian Gong Tong Shi 《International Journal of Automation and computing》 EI CSCD 2015年第6期648-656,共9页
A network time-delay compensation method based on time-delay prediction and implicit proportional-integral-based generalized predictive controller(PIGPC) is proposed. The least squares support vector machine(LSSVM) is... A network time-delay compensation method based on time-delay prediction and implicit proportional-integral-based generalized predictive controller(PIGPC) is proposed. The least squares support vector machine(LSSVM) is used to predict the current time-delay, the parameters of the least squares support vector machine are optimized by particle swarm optimization(PSO) algorithm,and the predicted time-delay is used instead of the actual time-delay as the parameters of the network time-delay compensation controller. In order to improve the compensation effect of implicit generalized predictive controller(GPC), this paper puts forward an implicit generalized predictive control algorithm with proportional-integral-based(PI) structure and designs the controller based on implicit PIGPC. Through the simulation results, the effectiveness of this design in the paper is verified. 展开更多
关键词 Networked control system time-delay compensation p
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Application of pH control to a tubular flow reactor 被引量:1
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作者 .Halil Vural Ayla Altinten +2 位作者 Hale Hapoglu Sebahat Erdogan Mustafa Alpbaz 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期154-161,共8页
Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the ... Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the present work, sodium hydroxide and acetic acid solutions were sent to the tubular flow reactor. The aim was to control p H at 7 in the nonlinear region. The p H control of a tubular flow reactor with high time delay and a highly nonlinear behavior in p H neutralization reaction was investigated experimentally in the face of the various load and set point changes. Firstly, efficiency of conventional Proportional-Integral-Derivative(PID) algorithm in the experiments was tested. Then self-tuning PID(STPID) control system was applied by using the ARMAX model. The model parameters were calculated from input–output data by using PRBS signal as disturbance and Bierman algorithm. Lastly, the experimental fuzzy control of p H based on fuzzy model was achieved to compare the success of fuzzy approach with the performance of other control cases studied. 展开更多
关键词 Tubular flow reactor p H control Self tuning pID control pID control fuzzy control
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Interval Type-2 Fuzzy Hierarchical Adaptive Cruise Following-Control for Intelligent Vehicles 被引量:5
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作者 Hong Mo Yinghui Meng +1 位作者 Fei-Yue Wang Dongrui Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第9期1658-1672,共15页
Intelligent vehicles can effectively improve traffic congestion and road traffic safety.Adaptive cruise followingcontrol(ACFC)is a vital part of intelligent vehicles.In this paper,a new hierarchical vehicle-following ... Intelligent vehicles can effectively improve traffic congestion and road traffic safety.Adaptive cruise followingcontrol(ACFC)is a vital part of intelligent vehicles.In this paper,a new hierarchical vehicle-following control strategy is presented by synthesizing the variable time headway model,type-2 fuzzy control,feedforward+fuzzy proportion integration(PI)feedback(F+FPIF)control,and inverse longitudinal dynamics model of vehicles.Firstly,a traditional variable time headway model is improved considering the acceleration of the lead car.Secondly,an interval type-2 fuzzy logic controller(IT2 FLC)is designed for the upper structure of the ACFC system to simulate the driver's operating habits.To reduce the nonlinear influence and improve the tracking accuracy for the desired acceleration,the control strategy of F+FPIF is given for the lower control structure.Thirdly,the lower control method proposed in this paper is compared with the fuzzy PI control and the traditional method(no lower controller for tracking desired acceleration)separately.Meanwhile,the proportion integration differentiation(PID),linear quadratic regulator(LQR),subsection function control(SFC)and type-1 fuzzy logic control(T1 FLC)are respectively compared with the IT2 FLC in control performance under different scenes.Finally,the simulation results show the effectiveness of IT2 FLC for the upper structure and F+FPIF control for the lower structure. 展开更多
关键词 Adaptive cruise following-control(ACfC) feedforward%pLUS%fuzzy proportion integration(pI)feedback(f%pLUS%fpIf) type-2 fuzzy control variable time headway
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光纤F-P腔高品质因子检波器理论模型研究
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作者 赵和平 刘波 +2 位作者 杨迪 闫诚 邢美华 《光学与光电技术》 2025年第5期108-117,共10页
针对波长解调型光纤加速度检波器灵敏度低的问题,建立了光纤法布里-珀罗(FabryPérot,F-P)波长解调型加速度检波器的理论模型。以光纤F-P加速度检波器的物理模型为切入点,结合F-P干涉仪的基本原理,理论研究其检波原理,并剖析弹性结... 针对波长解调型光纤加速度检波器灵敏度低的问题,建立了光纤法布里-珀罗(FabryPérot,F-P)波长解调型加速度检波器的理论模型。以光纤F-P加速度检波器的物理模型为切入点,结合F-P干涉仪的基本原理,理论研究其检波原理,并剖析弹性结构体的刚度、质量、腔长、阻尼和折射率对灵敏度的影响。通过实验搭建基于F-P干涉的光纤加速度检波器,验证了模型中主要参数对灵敏度和性能的影响。引入品质因子(Figure of Merit)作为指标,结合实验数据对传感器的综合性能进行量化评价,进一步验证了理论模型的正确性和适用性。对比分析FBG和F-P加速度传感器的综合性能,检波器的谐振频率约为740 Hz,在10~310 Hz频率范围较为平坦,相应的灵敏度为6.59~15.21 nm/G,动态范围达81.3 dB,动态分辨率6.25μG/√Hz,传感器灵敏度比基于FBG的传感器灵敏度理论上高出约2个数量级,为光纤类波长解调型高品质因子F-P加速度检波器的设计提供了新思路。 展开更多
关键词 品质因子 法布里-珀罗腔(f-p) 光纤检波器 加速度 波长调制
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远红外波段F-P可调滤波器的设计
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作者 赵倩倩 杜玉军 +3 位作者 魏威 鲁骞 杨锦航 郭彦双 《光学与光电技术》 2025年第2期31-38,共8页
为了实现气体成分判定和浓度定量检测,设计了9~12.6μm远红外波段的F-P可调滤波器,对于影响其光学性能的MEMS微结构特定光学元件进行了重点设计。为解决Si基底在9μm以上的光谱透过问题,设计了ZnS和BaF2双层材料构成的增透膜,使其透过率... 为了实现气体成分判定和浓度定量检测,设计了9~12.6μm远红外波段的F-P可调滤波器,对于影响其光学性能的MEMS微结构特定光学元件进行了重点设计。为解决Si基底在9μm以上的光谱透过问题,设计了ZnS和BaF2双层材料构成的增透膜,使其透过率在9~12.6μm范围内达到97%以上。移动反射镜和固定反射镜均采用由PbTe和BaF2组成的HLHLH高反膜,在所设计的光谱波段实现了高达98%的反射率。通过TFCalc和MATLAB软件仿真对设计进行验证,证明了设计的合理性。仿真结果可为远波段的可调滤波器设计提供借鉴,此类设计可广泛应用于气体传感器、环境监测、医学诊断设备等,特别是在小型化、集成化的传感器系统中。 展开更多
关键词 远红外波段 f-p可调滤波器 MEMS微结构 增透膜 反射镜
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The Main Diseases and Control Measures of Panax notoginseng(Burk) F. H. Chen in Wuzhou City 被引量:1
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作者 Chen Yinghui Liu Zhuowu +2 位作者 Qiu Weihua Tan Xinxing Li Jinfeng 《Plant Diseases and Pests》 CAS 2014年第2期35-37,共3页
The main symptoms of root rot,anthracnose,blight and damping-off of Panax notoginseng( Burk) F. H. Chen are introduced in the paper,and the corresponding control measures are elaborated from the aspects of agricultura... The main symptoms of root rot,anthracnose,blight and damping-off of Panax notoginseng( Burk) F. H. Chen are introduced in the paper,and the corresponding control measures are elaborated from the aspects of agricultural management measures,seed disinfection,seedbed treatment and chemical control. 展开更多
关键词 panax notoginseng(Burk) f.H.Chen DISEASES control Wuzhou
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