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香蕉枯萎病菌内源报告基因Foc4carS的鉴定及其应用
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作者 彭军 曾凡云 +5 位作者 王艳玮 漆艳香 丁兆建 王少伶 谢艺贤 张欣 《热带作物学报》 CSCD 北大核心 2024年第5期873-885,共13页
香蕉枯萎病是由尖孢镰刀菌古巴转化型(Fusarium oxysporum f. sp. cubense, Foc)引起的香蕉毁灭性土传病害,其中4号生理小种(Foc4)能感染几乎所有的香蕉品系,危害最严重。carS基因通过调控下游car结构基因参与调控镰刀菌类胡萝卜素的生... 香蕉枯萎病是由尖孢镰刀菌古巴转化型(Fusarium oxysporum f. sp. cubense, Foc)引起的香蕉毁灭性土传病害,其中4号生理小种(Foc4)能感染几乎所有的香蕉品系,危害最严重。carS基因通过调控下游car结构基因参与调控镰刀菌类胡萝卜素的生物合成,本研究克隆鉴定了Foc4carS基因(FOIG_05085),Foc4carS蛋白具有典型的RING-finger蛋白结构域。利用分割标记法(Split-marker PCR)获得Foc4carS基因的融合片段,同时构建含有Foc4carS基因sgRNA591序列的pUC-fFuCas9-HTBNLS-hph-Foc4carS基因编辑载体,通过PEG介导的原生质体转化获得该基因的敲除突变体、回补突变体以及基因编辑敲除体,并对敲除和回补突变体的生物学特性和致病力进行分析。结果显示:ΔFoc4carS突变体的菌落直径、产孢量和致病力等生物学表型与野生菌株Foc4无显著差异,而ΔFoc4carS突变体菌落颜色呈深橙色,Foc4carS基因的缺失影响了次生代谢产物类胡萝卜素的生物合成;基因编辑的ΔFoc4carS(HDR)突变体不论是再生筛选板还是继代后的PDA平板,其菌落均出现典型的深橙色,表明Foc4carS可作为内源报告基因,在香蕉枯萎菌Foc4中进行基因质粒型CRISPR/Cas9编辑可行。 展开更多
关键词 香蕉枯萎菌foc4 foc4carS基因 类胡萝卜素 基因敲除 CRISPR/Cas9基因编辑
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早期香蕉枯萎病Foc4双探针核酸纸基检测传感器研制
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作者 杨洲 区湘颖 +4 位作者 张志宏 罗宇康 何俊宇 欧俊辰 段洁利 《农业工程学报》 EI CAS CSCD 北大核心 2024年第5期38-46,共9页
为实现对早期香蕉枯萎病4号生理小种(fusarium oxysporum f.sp.cubense 4, Foc4)的准确检测,该研究提出一种基于胶体金的双探针纸基传感器。该传感器将2种不同粒径的胶体金分别与检测探针和信号增强探针结合,利用DNA探针代替抗原和抗体... 为实现对早期香蕉枯萎病4号生理小种(fusarium oxysporum f.sp.cubense 4, Foc4)的准确检测,该研究提出一种基于胶体金的双探针纸基传感器。该传感器将2种不同粒径的胶体金分别与检测探针和信号增强探针结合,利用DNA探针代替抗原和抗体,形成双探针体系,通过增加信号增强探针降低检测限。基于目标序列与双探针体系的碱基互补配对形成“金标探针-目标序列-T线探针”复合物并在传感器的测试区被捕获,10 min内形成肉眼可见的目标产物,通过分析测试条带得到光强度峰面积并代入标准曲线中,实现Foc4定量检测。试验结果表明,双探针纸基传感器的检测限达到0.001 nmol/L,是传统纸基传感器的100倍,提高了检测灵敏度;在0.001~1 000.000 nmol/L范围内,Foc4浓度与测试线光强度峰面积呈线性关系;使用高浓度非互补探针进行试验干扰,发现非互补序列对检测效果基本无影响,表明该传感器具有较好的特异性;香蕉叶片Foc4检测的平均回收率为77.6%~102.3%,相对标准偏差为7.4%~7.7%。与传统形态学观察等检测方法相比,该研究提出的双探针核酸纸基检测传感器可以及时、快速、准确地判断早期Foc4的存在,具有良好的推广性和实际应用价值。 展开更多
关键词 传感器 检测 foc4 双探针 胶体金 核酸侧向层析
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永磁同步电机FOC控制下相电流直流分量影响与抑制策略研究 被引量:1
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作者 王向恩 黄平林 《电子测量技术》 北大核心 2024年第2期61-68,共8页
永磁同步电机在矢量控制时需要对电机相电流进行采样,采样过程中参考电平波动等诸多因素都会造成相电流中包含直流分量,此外直流电压注入法等永磁同步电机参数在线估计方法,也会在相电流中引入直流分量。本文详细分析了不同情况下直流... 永磁同步电机在矢量控制时需要对电机相电流进行采样,采样过程中参考电平波动等诸多因素都会造成相电流中包含直流分量,此外直流电压注入法等永磁同步电机参数在线估计方法,也会在相电流中引入直流分量。本文详细分析了不同情况下直流分量的产生机理,研究了直流分量对控制效果、转矩脉动、效率等性能的影响。提出一种可滤除三相交流信号中直流分量的数据处理方法,该方法对不同因素引入的直流分量均能起到良好的抑制作用,从而增加控制稳定性,降低转矩波动,仿真和应用实践验证了算法有效性。 展开更多
关键词 永磁同步电机 foc矢量控制 直流分量 数据处理
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Cumulative effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease in China 被引量:6
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作者 Jing-Feng Chen Zhuo-Qing Wu +5 位作者 Hao-Shuang Liu Su Yan You-Xiang Wang Miao Xing Xiao-Qin Song Su-Ying Ding 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1346-1357,共12页
BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations ... BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively.METHODS A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected.The incidence rate,cumulative times,and equally and unequally weighted cumulative effects of excess high-normal ALT levels(ehALT)were measured.Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD.RESULTS A total of 83.13%of participants with MAFLD had normal ALT levels.The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group.Compared with those in the low-normal ALT group,the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651[95%confidence interval(CI):1.199-2.273]and 1.535(95%CI:1.119-2.106)in the third quartile and 1.616(95%CI:1.162-2.246)and 1.580(95%CI:1.155-2.162)in the fourth quartile,respectively.CONCLUSION Most participants with MAFLD had normal ALT levels.Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD. 展开更多
关键词 Metabolic dysfunction-associated fatty liver disease High-normal alanine aminotransferase level cumulative effect Cox proportional hazards regression Cohort study
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基于FOC的越野汽车系统设计与实现
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作者 戴测 袁杨洋 +1 位作者 许霄竹 沈世斌 《电子制作》 2024年第7期80-83,共4页
室外越野车辆目前广泛应用于军事、农业、工业之中,随着最近几年无人驾驶技术的兴起,室外无人越野车辆的研究也成了自动化设计领域的重点研究方向之一。其采用先进控制算法和传感器技术实现自主行驶本设计以室外越野车模为载体设计了基... 室外越野车辆目前广泛应用于军事、农业、工业之中,随着最近几年无人驾驶技术的兴起,室外无人越野车辆的研究也成了自动化设计领域的重点研究方向之一。其采用先进控制算法和传感器技术实现自主行驶本设计以室外越野车模为载体设计了基于英飞凌AURIX系列单片机的室外越野车硬件平台,该平台使用卫星定位模块与惯性测量单元实现定位功能。其中电机选择了直流无刷电机,对直流无刷电机的驱动方法进行研究,并设计了配套的无刷电机驱动软硬件,使用磁场定向控制的方法对无刷电机进行转动控制,为室外越野车提供了强劲的动力保证。 展开更多
关键词 foc PID 卡尔曼滤波 Infineon TC
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The Cumulative Method for Multiplication and Division
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作者 Muna Mohammed Hammuda 《Applied Mathematics》 2024年第5期349-354,共6页
This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularl... This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularly multiplication and division. The operations of multiplication and division are represented by algebraic formulas. An advantage of the method is that the cumulative process can be performed on decimal numbers. The present paper aims to establish a basic and useful formula valid for the two fundamental arithmetic operations of multiplication and division. The new cumulative method proved to be more flexible and made it possible to extend the multiplication and division based on repeated addition/subtraction to decimal numbers. 展开更多
关键词 Multiplication and Division cumulative Method Repeated Process Decimal Numbers
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Non-Gaussianity detection of single-mode rotationally symmetric quantum states via cumulant method
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作者 向少华 黄利军 米贤武 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期264-273,共10页
The non-Gaussianity of quantum states incarnates an important resource for improving the performance of continuous-variable quantum information protocols.We propose a novel criterion of non-Gaussianity for single-mode... The non-Gaussianity of quantum states incarnates an important resource for improving the performance of continuous-variable quantum information protocols.We propose a novel criterion of non-Gaussianity for single-mode rotationally symmetric quantum states via the squared Frobenius norm of higher-order cumulant matrix for the quadrature distribution function.As an application,we study the non-Gaussianities of three classes of single-mode symmetric non-Gaussian states:a mixture of vacuum and Fock states,single-photon added thermal states,and even/odd Schr¨odinger cat states.It is shown that such a criterion is faithful and effective for revealing non-Gaussianity.We further extend this criterion to two cases of symmetric multi-mode non-Gaussian states and non-symmetric single-mode non-Gaussian states. 展开更多
关键词 non-Gaussianity criterion cumulant matrix quadrature distribution
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The lithology and composition of lunar mantle modified by ilmenite bearing cumulate:A thermodynamic model
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作者 Wei Huang Wei Du 《Acta Geochimica》 EI CAS CSCD 2024年第5期856-875,共20页
Due to their high density,the ilmenite-bearing cumulates(IBC)(with or without KREEP)formed during the late-stage lunar magma ocean solidification are thought to sink into the underlying lunar mantle and trigger lunar ... Due to their high density,the ilmenite-bearing cumulates(IBC)(with or without KREEP)formed during the late-stage lunar magma ocean solidification are thought to sink into the underlying lunar mantle and trigger lunar mantle overturn.Geophysical evidence implied that IBC may descend deep inside the Moon and remain as a partially molten layer at the core-mantle boundary(CMB).However,partial melting may have occurred on the mixed mantle cumulates during the sinking of IBC/KREEP and the silicate melt may be positively buoyant,thus preventing the IBC/KREEP layer from sinking to the CMB.Here,we perform thermodynamic simulation on the stability of lunar mantle cumulates at different depths mixed with different amounts of IBC/KREEP from an updated LMO model.The modeling results suggest that the sinking of IBC/KREEP will cause at least 5 wt%partial melting in the shallow(~120 km)and a much larger degree of partial melting in the deep lunar mantle(~420 km).Due to the density contrast with the surrounding mantle,IBC/KREEP-bearing melts could potentially decouple under certain conditions.The modified lunar mantle by sinking of IBC/KREEP can better explain the formation of different kinds of lunar basaltic magma than the primary lunar mantle formed through differentiation of lunar magma ocean.Sinking of IBC/KREEP back into the lunar mantle may introduce plagioclase,clinopyroxene,garnet,and incompatible radioactive elements into the deep lunar mantle,which will further affect the thermal and chemical evolution of the lunar interior. 展开更多
关键词 Ilmenite-bearing cumulate KREEP Partial melting Lunar mantle overturn pMELTS
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Study on cumulative effects of biological craniocerebral trauma under repeated blast
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作者 Xingyuan Huang Bingchen Xia +3 位作者 Lijun Chang Zhikang Liao Hui Zhao Zhihua Cai 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期174-183,共10页
Repeated blast impacts on personnel in explosive environments can exacerbate craniocerebral trauma.Most existing studies focus on the injury effects of a single blast,lacking in-depth analysis on the injury effects an... Repeated blast impacts on personnel in explosive environments can exacerbate craniocerebral trauma.Most existing studies focus on the injury effects of a single blast,lacking in-depth analysis on the injury effects and cumulative effects of repeated blasts.Therefore,rats were used as the experimental samples to suffer from explosion blasts with different peak air overpressures(167 kPa~482 kPa)and varying number of repeated blasts.The cumulative effect of craniocerebral trauma was most pronounced for moderate repeated blast,showing approximately 95%increase of trauma severity with penta blast,and an approximately 85%increase of trauma severity with penta minor blast.The cumulative effect of craniocerebral trauma from severe,repeated blast has a smaller rate of change compared to the other two conditions.The severity of trauma from penta blast increased by approximately 69%compared to a single blast.Comprehensive physiological,pathological and biochemical analysis show that the degree of neurological trauma caused by repeated blasts is higher than that of single blasts,and the pathological trauma to brain tissue is more extensive and severe.The trauma degree remains unchanged after double blast,increases by one grade after triple or quadruple blast,and increases by two grades after penta blast. 展开更多
关键词 Repeated blast Craniocerebral trauma Trauma severity grade cumulative effects
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基于滑膜观测的FOC无刷电机控制系统设计
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作者 许为龙 徐宏宇 《机电工程技术》 2024年第1期159-162,211,共5页
针对目前全驱动型机器人的高工作精度以及高稳定性需求,设计全驱动型机器人关节驱动控制系统。基于无刷电机数学模型,电机驱动方案采用矢量电机控制算法FOC,电机角速度位置采用有感、无感相结合获取,即在启动以及低速转动下采用位置传感... 针对目前全驱动型机器人的高工作精度以及高稳定性需求,设计全驱动型机器人关节驱动控制系统。基于无刷电机数学模型,电机驱动方案采用矢量电机控制算法FOC,电机角速度位置采用有感、无感相结合获取,即在启动以及低速转动下采用位置传感器,在中高速转动下切换使用滑模观测器。观测器对电机反电动势观测值进行运算处理,获得电机位置和速度。在MATLAB/Simulink搭建控制模型,验证算法可行性。仿真结果表明:在负载情况下,中低转速下,控制精度低,低成本位置传感器足以满足控制需求;在中高转速下,位置获取方法切换为滑模观测器,此时无位置传感器控制,无需使用高精度位置传感器,根据电机运行的电流观测到的位置,足以满足中高转速需求。且观测器监测内部运行状态,无视外界影响,大大提高控制系统的响应性与稳定性。 展开更多
关键词 全驱动型机器人 无刷电机 电机控制算法 矢量控制(foc) 滑模观测器 无位置传感器控制
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Wigner function of optical cumulant operator and its dissipation in thermo-entangled state representation
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作者 张科 李兰兰 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期205-210,共6页
To conveniently calculate the Wigner function of the optical cumulant operator and its dissipation evolution in a thermal environment, in this paper, the thermo-entangled state representation is introduced to derive t... To conveniently calculate the Wigner function of the optical cumulant operator and its dissipation evolution in a thermal environment, in this paper, the thermo-entangled state representation is introduced to derive the general evolution formula of the Wigner function, and its relation to Weyl correspondence is also discussed. The method of integration within the ordered product of operators is essential to our discussion. 展开更多
关键词 Wigner function optical cumulant operator dissipation evolution thermo-entangled state representation integration within ordered product of operators
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Development of a novel critical nitrogen concentration-cumulative transpiration curve for optimizing nitrogen management under varying irrigation conditions in winter wheat
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作者 Tianyang Ye Yu Zhang +9 位作者 Jingyan Xuan Xintian Wang Yang Li Junhao Xu Liujun Xiao Leilei Liu Liang Tang Weixing Cao Bing Liu Yan Zhu 《The Crop Journal》 SCIE CSCD 2024年第4期1242-1251,共10页
Accurate nitrogen(N)nutrition diagnosis is essential for improving N use efficiency in crop production.The widely used critical N(Nc)dilution curve traditionally depends solely on agronomic variables,neglecting crop w... Accurate nitrogen(N)nutrition diagnosis is essential for improving N use efficiency in crop production.The widely used critical N(Nc)dilution curve traditionally depends solely on agronomic variables,neglecting crop water status.With three-year field experiments with winter wheat,encompassing two irrigation levels(rainfed and irrigation at jointing and anthesis)and three N levels(0,180,and 270 kg ha1),this study aims to establish a novel approach for determining the Nc dilution curve based on crop cumulative transpiration(T),providing a comprehensive analysis of the interaction between N and water availability.The Nc curves derived from both crop dry matter(DM)and T demonstrated N concentration dilution under different conditions with different parameters.The equation Nc=6.43T0.24 established a consistent relationship across varying irrigation regimes.Independent test results indicated that the nitrogen nutrition index(NNI),calculated from this curve,effectively identifies and quantifies the two sources of N deficiency:insufficient N supply in the soil and insufficient soil water concentration leading to decreased N availability for root absorption.Additionally,the NNI calculated from the Nc-DM and Nc-T curves exhibited a strong negative correlation with accumulated N deficit(Nand)and a positive correlation with relative grain yield(RGY).The NNI derived from the Nc-T curve outperformed the NNI derived from the Nc-DM curve concerning its relationship with Nand and RGY,as indicated by larger R2 values and smaller AIC.The novel Nc curve based on T serves as an effective diagnostic tool for assessing winter wheat N status,predicting grain yield,and optimizing N fertilizer management across varying irrigation conditions.These findings would provide new insights and methods to improve the simulations of water-N interaction relationship in crop growth models. 展开更多
关键词 Crop dry matter Crop cumulative transpiration Bayesian statistical model Critical nitrogen dilution curve Nitrogen nutrition index
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基于无感FOC的一体式无刷电机控制驱动器的电路系统
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作者 邱亿龙 凌子强 +3 位作者 罗宇浩 林锦亮 谢仲业 王福杰 《工业控制计算机》 2024年第10期129-131,共3页
针对无感方波控制时,存在控制精度低,电流采样误差大,低速启动性能较差等问题。设计了一种基于无感FOC的一体式无刷电机控制驱动器的电路系统。系统以TI公司的大电流栅极驱动器DRV8301为预驱核心,设计了数模耦合电路及高端电流采样电路... 针对无感方波控制时,存在控制精度低,电流采样误差大,低速启动性能较差等问题。设计了一种基于无感FOC的一体式无刷电机控制驱动器的电路系统。系统以TI公司的大电流栅极驱动器DRV8301为预驱核心,设计了数模耦合电路及高端电流采样电路,实现了控制器和驱动器的高度集成,减少了电流采样误差。经实验测试表明,所设计的电路系统能够实现FOC正弦波的稳定输出,持续输出功率可达上千瓦,实时电流监测误差不超过1%,具有体积小、高爆发、高精度控制、响应速度快等优点,可广泛用于工业自动化控制等领域。 展开更多
关键词 无感foc 一体式无刷电机控制驱动器 数模耦合电路 DRV8301
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Cumulative Air Quality Impacts from Twenty-Two Major Power Plants
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作者 Md M.Karim Navin Bindra Arub Masud 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第1期1-14,共14页
Cumulative assessment is a tool for the project developer to try and take into consideration not only their contribution to cumulative impacts but also other projects and external factors that may place their developm... Cumulative assessment is a tool for the project developer to try and take into consideration not only their contribution to cumulative impacts but also other projects and external factors that may place their developments at risk.This study assessed the cumulative impacts of air emissions from 22 major power plants in southeast Bangladesh planned to generate 21,550 MW of electricity.It also includes anticipated growth in small to medium size industries,brickfields,highway traffic,inland water transport,transhippers,jetty,and vessel transports used for transporting fuel resources for these power plants.A 50 km by 50 km airshed is considered for air quality modeling.Cumulative analysis indicates that predicted MGLCs(Maximum Ground Level Concentrations)of NO2 and CO are complying with both Bangladesh NAAQS(National Ambient Air Quality Standards)and WBG(World Bank Group)Guidelines.The daily average MGLC of PM_(2.5)(62.45µg/m^(3))from all sources complies with NAAQS,however,exceeds the WBG Guidelines.Annual PM_(2.5) concentration(15.45µg/m^(3))exceeds NAAQS and WBG Guidelines.The PM10 concentration complies with the NAAQS for both 24-hour and annual averaging times.Annual average concentration(23.12µg/m^(3))exceeds WBG Guidelines.Daily average SO2 concentration(102.49µg/m^(3))complies with the NAAQS however,it exceeds the WBG guideline values.High concentrations of PM_(2.5) and SO2 are due to the contribution of transboundary emissions and secondary pollutants in the atmosphere.This dispersion modeling outcome can be used by the policymakers for the pollution reduction strategy. 展开更多
关键词 CIA(cumulative Impact Assessment) dispersion modeling power generation Bangladesh.
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基于FOC矢量控制技术的BLDC电机研究
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作者 金建军 陈丹 +2 位作者 付世彪 夏琪 沈禹诺 《中文科技期刊数据库(文摘版)工程技术》 2024年第9期140-144,共5页
本文运用了先进的FOC矢量控制技术,对BLDC电机进行了深入研究。通过开发无位置传感检测算法,针对BLDC电机的支架与风道、导风轮与转子、动叶轮与风罩等结构进行优化设计,同时建立数字化研发设计平台,依托工业物联网实现智能化生产。研... 本文运用了先进的FOC矢量控制技术,对BLDC电机进行了深入研究。通过开发无位置传感检测算法,针对BLDC电机的支架与风道、导风轮与转子、动叶轮与风罩等结构进行优化设计,同时建立数字化研发设计平台,依托工业物联网实现智能化生产。研究致力于优化提升BLDC电机控制系统的性能和可靠性,为多个领域的广泛应用提供有力支持,推动行业电机技术的创新和发展。 展开更多
关键词 foc BLDC 数字化研发 智能生产
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Joint estimation of DOA, frequency, and polarization based on cumulants and UCA 被引量:7
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作者 Huang Jiacai Shi Yaowu Tao Jianwu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期704-709,共6页
A joint estimation algorithm of direction of arrival (DOA), frequency, and polarization, based on fourth-order cumulants and uniform circular array (UCA) of trimmed vector sensors is presented for narrowband non-G... A joint estimation algorithm of direction of arrival (DOA), frequency, and polarization, based on fourth-order cumulants and uniform circular array (UCA) of trimmed vector sensors is presented for narrowband non-Gaussian signals. The proposed approach, which is suitable for applications in arbitrary Gaussian noise environments, gives a closed-form representation of the estimated parameters, without spectral peak searching. An efficient method is also provided for elimination of cyclic phase ambiguities. Simulations are presented to show the performance of the algorithm. 展开更多
关键词 POLARIZATION direction of arrival FREQUENCY fourth-order cumulant uniform circular array vector sensor
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Resolution performance analysis of cumulants-based rank reduction estimator in presence of unexpected modeling errors
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作者 王鼎 吴瑛 《Journal of Central South University》 SCIE EI CAS 2013年第11期3116-3130,共15页
Compared to the rank reduction estimator (RARE) based on second-order statistics (called SOS-RARE), the RARE employing fourth-order cumulants (referred to as FOC-RARE) is capable of dealing with more sources and... Compared to the rank reduction estimator (RARE) based on second-order statistics (called SOS-RARE), the RARE employing fourth-order cumulants (referred to as FOC-RARE) is capable of dealing with more sources and mitigating the negative influences of the Gaussian colored noise. However, in the presence of unexpected modeling errors, the resolution behavior of the FOC-RARE also deteriorate significantly as SOS-RARE, even for a known array covariance matrix. For this reason, the angle resolution capability of the FOC-RARE was theoretically analyzed. Firstly, the explicit formula for the mathematical expectation of the FOC-RARE spatial spectrum was derived through the second-order perturbation analysis method. Then, with the assumption that the unexpected modeling errors were drawn from complex circular Gaussian distribution, the theoretical formulas for the angle resolution probability of the FOC-RARE were presented. Numerical experiments validate our analytical results and demonstrate that the FOC-RARE has higher robustness to the unexpected modeling en'ors than that of the SOS-RARE from the resolution point of view. 展开更多
关键词 performance analysis rank reduction estimator (RARE) fourth-order cumulants (foc spatial spectrum angle resolution probability unexpected modeling errors
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Application of Three Order Cumulants in Fault Diagnosis 被引量:1
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作者 Wenbing Wu 《International Journal of Modern Nonlinear Theory and Application》 2018年第4期97-105,共9页
The three-order cumulants’ complex forms of different definitions include different coupling information of signals, and the information can be used to diagnose fault. In the experiment of pressure reducing valve’s ... The three-order cumulants’ complex forms of different definitions include different coupling information of signals, and the information can be used to diagnose fault. In the experiment of pressure reducing valve’s fault diagnosis, through these different coupling information, the features of fault signals and normal signals were extracted by wavelet in different directions, then these features were inputted to diagnose the fault. The experiment shows that this method can achieve a satisfactory result. 展开更多
关键词 cumulants COUPLING WAVELET FAULT DIAGNOSIS
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Signal Classification Method Based on Support Vector Machine and High-Order Cumulants 被引量:1
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作者 Xin ZHOU Ying WU Bin YANG 《Wireless Sensor Network》 2010年第1期48-52,共5页
In this paper, a classification method based on Support Vector Machine (SVM) is given in the digital modulation signal classification. The second, fourth and sixth order cumulants of the received signals are used as c... In this paper, a classification method based on Support Vector Machine (SVM) is given in the digital modulation signal classification. The second, fourth and sixth order cumulants of the received signals are used as classification vectors firstly, then the kernel thought is used to map the feature vector to the high dimensional feature space and the optimum separating hyperplane is constructed in space to realize signal recognition. In order to build an effective and robust SVM classifier, the radial basis kernel function is selected, one against one or one against rest of multi-class classifier is designed, and method of parameter selection using cross- validation grid is adopted. Through the experiments it can be concluded that the classifier based on SVM has high performance and is more robust. 展开更多
关键词 HIGH-ORDER cumulants Support VECTOR Machine KERNEL Function SIGNAL Classification
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基于STM32F411的无刷直流电机FOC控制系统设计 被引量:6
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作者 徐扬 张兰红 陈永楼 《微特电机》 2023年第5期61-65,71,共6页
以STM32F411CEU6单片机作为主控制芯片,采用矢量控制策略,设计了一种基于STM32F411的无刷直流电机矢量控制系统,实验结果表明,该无刷直流电机矢量控制系统可以对电机的转速进行精准的控制。
关键词 无刷直流电机 磁场定向控制 转速控制 STM32F411
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