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基于DSOGI-PLL与ANF-LPF的i_(p)-i_(q)三相谐波检测方法

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现代电子技术 2024年第8期47卷 121-125页

作者：马玉立原浩陈良亮赵阳国电南瑞南京控制系统有限公司江苏南京210000 南瑞集团(国网电力科学研究院)有限公司江苏南京210000 南京师范大学电气与自动化工程学院江苏南京210000

随着分布式电源大规模接入电网,电力系统中频率波动、电压不平衡以及谐波畸变等问题日益严重。在这样不平衡和失真的电网条件下,传统i_(p)-i_(q)谐波检测法已不能满足工程需要。为解决这一问题,文中提出一种基于DSOGI-PLL与ANF-LPF的i_(... 详细信息

随着分布式电源大规模接入电网,电力系统中频率波动、电压不平衡以及谐波畸变等问题日益严重。在这样不平衡和失真的电网条件下,传统i_(p)-i_(q)谐波检测法已不能满足工程需要。为解决这一问题,文中提出一种基于DSOGI-PLL与ANF-LPF的i_(p)-i_(q)三相谐波检测方法。一方面,采用DSOGI-PLL提高复杂电网下提取基波相位的能力;另一方面,采用一种具有选择性谐波滤波能力的改进结构LPF,来提高谐波检测的抗干扰能力。结果表明,所提方法能够在复杂电网条件下完成三相谐波检测。

关键词：双二阶广义积分器谐波检测陷波器低通滤波器锁相环瞬时无功理论 ip-iq 基波电流

Design of training sequence based on iq imbalance estimation in CO-OFDM system

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Optoelectronics Letters 2023年第8期19卷 476-480页

作者： CHEN Yu ma Xiurong LI Jingjing Engineering Research Center of Optoelectronic Devices and Communication Technology Ministry of EducationTianjin University of TechnologyTianjin 300384China

In this paper,a new training sequence structure is proposed,which estimates the in-phase/quadrature(iq) imbalance factor and channel information in coherent optical orthogonal frequency division multiplexing(CO-OFDM) systems with phase noise caused by laser *** given training sequence structure consists of four *** first two training symbols have two subsets:a non-zero subset and a zero set mirror position *** non-zero subset is used to estimate the channel information,the mirror position subset is used to estimate the iq imbalance factor,and the last two symbols are also used to estimate the iq imbalance factor at the *** method can realize independent compensation for iq imbalance and channel distortion,and improve the system performance when the data rate is 10 Gbit/s higher than the traditional method.

关键词： channel mirror system

IDEAL-iq序列在冈上肌腱损伤后肩袖肌群脂肪浸润定量评估中的应用

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磁共振成像 2024年第10期15卷 115-122页

作者：徐奋玲田兆荣田博龚瑞马芳芳胡靖波王志军宁夏医科大学第一临床医学院宁夏医科大学总医院放射科

目的采用非对称采集与迭代最小二乘估算法迭代水脂分离（iteraterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation, IDEAL-iq）方法定量评估冈上肌腱损伤的严重程度与肩袖肌群脂肪浸润程度及受试者特征之间的关系。材料与方法回顾性分析2022年8月至2024年6月本院经肩关节镜证实的33例冈上肌腱部分撕裂患者及89例完全撕裂患者，均进行了常规MRI扫描及IDEAL-iq序列扫描。由两名放射科医生分别对所有受试者的MRI图像进行独立评估，根据常规MRI图像的冈上肌腱损伤表现，将完全撕裂组的冈上肌腱按照Patte分型分为Patte 1型（Ⅱ级）、Patte 2型（Ⅲ级）、Patte 3型（Ⅳ级），将部分撕裂组定义为Ⅰ级。同时在斜矢状位上进行Goutallier分级及Thomazeau萎缩分级，并通过GE ADW 4.7工作站后处理软件在IDEAL-iq序列生成的脂肪分数图像上测量冈上肌、冈下肌、肩胛下肌及小圆肌脂肪分数（fat fraction, FF）。用组内相关系数（intra-class correlation coefficient, ICC）及Kappa一致性检验评估观察者间及观察者内的一致性。采用Kruskal-Wallis H检验、单因素ANOVA检验分析FF值在不同分组之间的差异，组间两两比较用Bonferroni检验。采用Pearson相关性分析肩袖肌肉FF值与年龄、症状持续时间的相关性（相关系数r）,Spearman相关性分析冈上肌腱损伤分级与肩袖肌群FF值、Goutallier分级及Thomazeau萎缩分级之间的相关性（相关系数rs）。结果（1）冈上肌、冈下肌、肩胛下肌的FF值在冈上肌腱损伤Ⅳ级中显著高于Ⅲ级，高于Ⅱ级和Ⅰ级，差异有统计学意义（P值分别为mazeau分级之间呈显著正相关（rs分别为0.757、0.737,P均mazeau的分级中差异具有统计学意义（P均iq序列能量化和客观评估肩袖肌群脂肪浸润程度，肩袖肌群脂肪浸润程度与冈上肌腱损伤分级呈正相关，与年龄、症状持续时间呈正相关。

关键词：冈上肌腱 Patte分型 Goutallier分级肩袖肌群脂肪定量 IDEAL-iq 脂肪分数磁共振成像

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不同成像参数下CBCT的成像质量分析

实用口腔医学杂志 2024年第2期40卷 222-226页

作者：钱军马芮谢晓艳姜丹邓少纯段瑶毋育伟北京大学口腔医学院·口腔医院第二门诊部 100020 北京大学口腔医学院·口腔医院放射科 100020

目的:主观评价和客观评估不同成像参数下CBCT的图像质量,分析图像质量的主观评价和客观评价间的关系。方法:分别采用6台不同品牌CBCT扫描仪〔3D Accuitomo(Morita)、i-CAT(Kavo)、5G(NewTom)、Smart3D(北京朗视)、DCT Pro(Vatech)、VGi(... 详细信息

目的:主观评价和客观评估不同成像参数下CBCT的图像质量,分析图像质量的主观评价和客观评价间的关系。方法:分别采用6台不同品牌CBCT扫描仪〔3D Accuitomo(Morita)、i-CAT(Kavo)、5G(NewTom)、Smart3D(北京朗视)、DCT Pro(Vatech)、VGi(NewTom)〕,在各个品牌的典型曝光条件下(电压和电流强度不同)扫描空间分辨率模体和高仿真头模,7位医师对拍摄的CBCT图像进行主观评价打分,比较不同CBCT扫描仪的空间分辨率和对常见口腔解剖结构的可见性。客观评价指标采用各仪器所获的图像空间分辩率(LP/mm)。结果:7位医师的组内一致性和组间一致性均无显著性差异。主观评价New Tom 5G为2分,i-CAT为5分,其余4个品牌匀为4分,客观评价i-CAT的LP/mm为1.8,Smart3D为2.0,其余4个品牌为1.0~1.7。在相同管电流条件下,不同管电压的图像主观质量有显著性差异。在相同管电压条件下,不同管电流的图像主观质量有显著性差异。结论:图像质量的主客观评价具有一定的一致性,不同品牌之间的客观评价差异可能与电压、电流强度不同有关。

关键词：锥形束计算机断层扫描图像质量主观评价客观评价

GhiqD10 interacts with GhCaM7 to control cotton fiber elongation via calcium signaling

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The Crop Journal 2023年第2期11卷 447-456页

作者： Fan Xu Li Wang Jun Xu Qian Chen Caixia ma Li Huang Guiming Li Ming Luo Key Laboratory of Biotechnology and Crop Quality Improvement of the Ministry of Agriculture Biotechnology Research CenterSouthwest UniversityChongqing 400715China Zhengzhou Research Base State Key Laboratory of Cotton BiologyZhengzhou UniversityZhengzhou 450001HenanChina Academy of Agricultural Sciences of Southwest University State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest UniversityChongqing 400715China

iq67-domain(iqD)proteins function in plant defense and in organ *** mechanisms by which they influence cotton fiber development are *** the present study,GhiqD10 was expressed mainly in the transition period of cotton fiber development,and GhiqD10-overexpression lines showed shorter ***10 interacted with GhCaM7 and the interaction was inhibited by Ca^(2+).In in vitro ovule culture,Ca^(2+)rescued the shorter-fiber phenotype of GhiqD10-overexpression lines,which were insensitive to the Ca^(2+)channel inhibitor verapamil and the Ca^(2+)pool release channel blocker 2-aminoethoxydiphenyl *** conclude that GhiqD10 affects cotton fiber elongation via Ca^(2+)signaling by interacting with ***(BR)biosynthesis and signaling genes were up-regulated in GhiqD10-overexpression *** development in these lines was not affected by epibrassinolide or the BR biosynthesis inhibitor brassinozole,indicating that the influence of GhiqD10 on fiber elongation was not associated with BR.

关键词： Cotton Fiber elongation iq67-domian protein Ca^(2+) Brassinosteroid

maGiC联合IDEAL iq技术在皮肌炎/多发性肌炎定量诊断中应用

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中国临床医学影像杂志 2024年第2期35卷 137-141页

作者：王玉琪田兆荣龚瑞田博徐奋玲马芳芳王志军宁夏医科大学临床医学院宁夏银川750001 宁夏医科大学总医院放射科宁夏银川750001

目的:探讨MR集成(magnetic resonance image compilation,maGiC)序列联合非对称采集技术和迭代最小二乘估算法迭代水脂分离算法(IDEAL-iq)在皮肌炎(Dermatomyositis,DM)/多发性肌炎(Polymyositis,PM)患者大腿肌肉定量诊断中的价值。资料与方法:回顾性收集宁夏医科大学总医院经临床及病理证实为PM/DM的患者67例(病例组),年龄、性别、体质量指数(BMI)相匹配志愿者23例(对照组),采用SIGNA Architect 3.0T扫描仪行双大腿maGiC序列、IDEAL iq序列及常规T_(1)WI、T_(2)WI、T_(2)Flex序列扫描。由两名放射科医生以独立双盲法于各序列上测量12块肌肉(阔筋膜张肌,缝匠肌,股四头肌,大收肌,长收肌,股薄肌,半膜肌,半腱肌,股二头肌)的T_(2)值、T_(1)值、PD值、FF值及R_(2)*值。通过单因素方差分析比较不同组T_(2)值、T_1值、PD值、FF值及R_(2)*值。通过受试者工作特征(ROC)曲线,分析T_(2)值、PD值、FF值及R_(2)*值、T_(2)值与FF值两者联合及EMG对DM/PM的诊断效能。结果:(1)DM/PM病例组T_(2)值高于对照组(Z=-19.818,PmaGiC定量图谱技术可定量DM/PM患者大腿肌肉水肿程度,IDEAL iq序列能定量大腿脂肪浸润情况,两者联合应用明显提高了DM/PM的诊断效能。

关键词：皮肌炎磁共振成像

Joint estimation and compensation of transceiver iq imbalance for PDM CO-OFDM system

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Optoelectronics Letters 2021年第3期17卷 144-148页

作者： ma Xiu-rong YANG Meng SHAN Yun-long LI Jing-jing Engineering Research Center of Optoelectronic Devices and Communication Technology Ministry of EducationTianjin University of TechnologyTianjin 300384China

In this paper, a frequency-domain mathematical model is deduced for polarization-division multiplexing(PDM) coherent optical orthogonal frequency division multiplexing(CO-OFDM) system with transceiver in-phase and quadrature(iq) imbalances. A novel training symbol structure is designed in which the mirror-subcarriers of pilot subcarriers were modulated with zero signal so that the channel distortion with transceiver iq imbalances can be estimated. It proves that the channel distortion and transmitter iq imbalances cannot be separated using the training symbols;therefore, the channel equalization method was used to recover the signals. Simulation results show that at 2 dB transmitter amplitude imbalances, 15° transmitter phase imbalances, 100 Gbit/s transmission rate, 1 040 km standard signal-mode fiber link, and 1×10^(-3) bit error rate, 23.5 dB optical signal-to-noise ratio(OSNR) is necessary for the proposed method. However, the compared schemes cannot achieve effective transmission.

关键词： transceiver polarization distortion

Effect of High-Order Aberrations and Satisfaction on Cataract Patients Implanted with Four Types of AcrySof Blue Light Filtering Intraocular Lens

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International Journal of Clinical Medicine 2021年第8期12卷 307-315页

作者： Wei Wu Shengyou Yu Shengsheng ma Department of Ophthalmology Guangzhou Red Cross Hospital Jinan University Guangzhou China Department of Pediatrics Guangzhou First People’s Hospital School of Medicine South China University of Technology Guangzhou China

Objective: The objective is to evaluate the visual acuity, high-order aberrations and satisfaction in the cataract patients with the implantation of different types of AcrySof blue light filtering intraocular lens, which would provide the clinical guidance for the selection of individualized intraocular lens. Methods: From January 2019 to December 2020, the patients with age-related cataract in Guangzhou Red Cross Hospital were equally randomized to be divided into four groups. 20 patients (20 eyes) were implanted with AcrySof (SN60WF), which was the blue light filtering single focus group;20 patients (20 eyes) were implanted with blue light filtering aspheric multifocal intraocular lens (AcrySof ReSTOR IOL +3.0D, SN6AD1), which was the multifocal intraocular lens group;20 patients (20 eyes) were implanted with aspheric astigmatism correction intraocular lens (Toric SN6AT), which was the astigmatism group;20 patients (20 eyes) were implanted with blue filtering aspheric multifocal astigmatism correction intraocular lens (AcrySof ReSTOR IOL +2.5D iq, SV25T0), which was the ART group. Three months after the operation, the patients were followed up with slit lamp to check the visual acuity, including uncorrected distance visual acuity (UCDVA), uncorrected near visual acuity (UCNVA), best corrected distance visual acuity, (BCDVA);the questionnaire surveys on the satisfaction of different intraocular lens implantation (far and near vision, glare, halo and abnormal visual symptoms);the iTrace visual function analyzer was used to check the total high-order aberrations (spherical aberration, wisdom aberration and Clover aberration) in the 3 mm pupil diameter. Results: Three months after cataract surgery, American Simplified version of questionnaire survey showed that the scores of near removing glasses in the multifocal group and the ART group were significantly better than those in the single focus group and the astigmatis

关键词： Cataract Intraocular Lens High-Order Aberrations Blue Light Filtering

A single-step synthesis of nitrogen-doped graphene sheets decorated with cobalt hydroxide nanoflakes for the determination of dopamine

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Progress in Natural Science:materials International 2017年第5期27卷 582-587页

作者： Muhammad Mehmood Shahid Ahmad H.Ismail Ali ma.Abdul Amir AL-Mokaram R.Vikneswaran Sohail Ahmad Amir Hamza Arshid Numan Department of Physics Faculty of ScienceUniversity of Malaya Department of Chemistry College of ScienceMustansiriyah University Department of Chemistry Faculty of ScienceUniversity of Malaya Nanotechnology & Catalysis Research Centre University of Malaya 5. Faculty of ScienceUniversity of Haripur

Nitrogen-doped reduced graphene oxide（NrGO）sheets decorated with Co（OH）;nanoflakes were prepared by a single-step hydrothermal *** morphological and structural characterizations of as synthesized Nr GO@Co（OH）;nanoflakes were performed by field emission scanning electron microscopy（FESEM）,EDX-mapping and X-ray diffraction（XRD）.Nr GO@Co（OH）;nanoflakes modified glassy carbon electrode（GCE）was used for electrochemical sensing of dopamine in neutral *** nanocomposite modified electrode showed enhanced electrochemical sensing ability for the detection of dopamine and the limit of detection（Lo D）was found to be 0.201μM with a sensitivity value of 0.0286±0.002 m A m M;.Interference studies revealed that Nr GO@Co（OH）;─GCE endow excellent selectivity for DA detection even in the presence of higher concentration of common co-existing physiological interfering ***,proposed sensor demonstrated excellent performance in urine samples with promising reproducibility and stability.

关键词： Nitrogen doped graphene Dopamine Electrochemical sensor Amperometric detection