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A Mapping Technique to Draw Resistivity Isocontours for Slice-of-Silicon Monocrystal 被引量:1
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作者 孙以材 潘国峰 +2 位作者 杨茂峰 叶威 张鹏 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第7期1281-1285,共5页
A resistivity distribution with a space of 3mm between test points was measured on a slice-of-silicon monocrystal (diameter 75mm) using an inclined four-point probe. This paper has determined the number of resistivi... A resistivity distribution with a space of 3mm between test points was measured on a slice-of-silicon monocrystal (diameter 75mm) using an inclined four-point probe. This paper has determined the number of resistivity divisions and their separations by statistical methods and introduced fuzzy mathematics to place the data into different fuzzy sets, after choosing the exponent function as a membership function for fuzzy sets and suitable values of thresholds. One fuzzy set corresponds to one resistivity isocontour. Then,the resistivity isocontours can be drawn with a definite separation and fi- nally shown in a map with MATLAB. The deviation of resistivity data on an isocontour is small and there are few residual test points without connections. So, the connection of the isocontours are high-quality and useful in application for instructing practical production. 展开更多
关键词 mapping technique silicon monocrystal draw the resistivity isocontours
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Hydrochemical characterization of surface waters in Northern Tehran: Integrating cluster-based techniques with Self-Organizing Maps
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作者 Maryam SALIMI Hamid Reza NASSERY +2 位作者 Meysam VADIATI Prosun BHATTACHARYA Akram RAHBAR 《Journal of Mountain Science》 2025年第7期2370-2390,共21页
Water quality is a critical global issue,especially in urban and semi-urban regions where natural and anthropogenic factors significantly influence surface water systems.This study evaluates the hydrochemical characte... Water quality is a critical global issue,especially in urban and semi-urban regions where natural and anthropogenic factors significantly influence surface water systems.This study evaluates the hydrochemical characteristics of surface water in the North of Tehran Rivers(NTRs),an essential water resource in a rapidly urbanizing region,using advanced clustering techniques,including Hierarchical Clustering Analysis(HCA),Fuzzy CMeans(FCM),Genetic Algorithm Fuzzy C-Means(GAFCM),and Self-Organizing Map(SOM).The research aims to address the scientific challenge of understanding spatial and temporal variability in water quality,focusing on physicochemical parameters,hydrochemical facies,and contamination sources.Water samples from six rivers collected over four seasons in 2020 were analyzed and classified into distinct clusters based on their chemical composition,revealing significant seasonal and spatial differences.Results showed that FCM and GAFCM consistently categorized the NTRs into two clusters during winter and spring and three in summer and autumn.These findings were supported by HCA and SOM,which identified clusters corresponding to specific river segments and contamination levels.The primary hydrochemical processes identified were mineral dissolution and weathering,with calcite,dolomite,and aragonite significantly influencing water chemistry.Additionally,human activities,such as wastewater discharge,were shown to contribute to elevated sulfate,nitrate,and phosphate concentrations,further corroborated by microbial analyses.By integrating HCA,FCM,and GAFCM with an artificial neural network(ANN)-based clustering method(SOM),this study provides a robust framework for evaluating surface water quality.The findings,supported by Gibbs diagrams,Hounslow ion ratio,and saturation indices,highlight the dominance of rock weathering and human impacts in shaping the hydrochemical dynamics of the NTRs.These insights contribute to the scientific understanding of water quality dynamics and offer practical guidance for sustainable water resource management and environmental protection in developing urban areas. 展开更多
关键词 Hydrochemical characteristics Clustering techniques Contamination sources Tehran Rivers Self Organizing map Surface water quality
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Erratum to:Hydrochemical characterization of surface waters in Northen Tehran:Integrating cluster-based techniques with Self-Organizing Maps
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作者 Maryam SALIMI Hamid Reza NASSERY +2 位作者 Meysam VADIATI Prosun BHATTACHARYA Akram RAHBAR 《Journal of Mountain Science》 2025年第9期3527-3527,共1页
The title of the online version of the original article was revised.The title of the original article has been revised to:Hydrochemical characterization of surface waters in Northern Tehran:Integrating cluster-based t... The title of the online version of the original article was revised.The title of the original article has been revised to:Hydrochemical characterization of surface waters in Northern Tehran:Integrating cluster-based techniques with Self-Organizing Maps. 展开更多
关键词 northern tehran cluster based techniques characterization surface waters hydrochemical characterization surface waters self organizing maps
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Application of Different Image Processing Techniques on Aster and ETM+ Images for Exploration of Hydrothermal Alteration Associated with Copper Mineralizations Mapping Kehdolan Area (Eastern Azarbaijan Province-Iran) 被引量:2
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作者 Golchin Hajibapir Mohammad Lotfi +1 位作者 Afshar Zia Zarifi Nima Nezafati 《Open Journal of Geology》 2014年第11期582-597,共16页
The Kehdolan area is located at 20 kilometers to the?south-east of Dozdozan Town (Eastern Azarbaijan Province). According to structural geology, volconic rocks are situated in Alborz-Azarbyjan zone, and faults?are?obs... The Kehdolan area is located at 20 kilometers to the?south-east of Dozdozan Town (Eastern Azarbaijan Province). According to structural geology, volconic rocks are situated in Alborz-Azarbyjan zone, and faults?are?observed?in?the?same direction to this system with SE-NW trend. The results show that kaolinite alteration trend with Argilic and propylitic veins?is the?same direction with SW-NE faults in this area. Therefore, these faults with these trends can be considered as the mineralization control for determination of the alterations. Different image processing techniques,?such as false color composite?(FCC), band ratios, color ratio composite?(CRC), principal component?analysis?(PCA), Crosta technique, supervised spectral angle mapping?(SAM), are used for?identification of the alteration zones associated with copper mineralization. In this project ASTER?data are process and spectral analysis to fit for recognizing intensity and kind of argillic, propylitic,?philic, and ETM+ data?which?are process and to fit for iron oxide and relation to metal mineralization of the area. For recognizing different alterations of the study area, some chemical and mineralogical analysis data from the samples showed that ASTER data and ETM+ data were?capable of hydrothermal alteration mapping with copper mineralization.?Copper mineralization in the region is in agreement with argillic alteration. SW-NE trending faults controlled the mineralization process. 展开更多
关键词 Kehdolan Area False COLOR COMPOSITE Band Ratios COLOR Ratio COMPOSITE Principal Component Analysis Crosta technique Supervised Spectral Angle mapping ASTER DATA ETM+ DATA Alteration
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A Sensitivity Mapping Technique for Tensile Force and Case Depth Characterization Based on Magnetic Minor Hysteresis Loops 被引量:1
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作者 Cunfu He Wenqiao Dou +2 位作者 Xiucheng Liu Meng Yang Ruifang Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第6期93-104,共12页
In the nondestructive testing and evaluation area,magnetic major hysteresis loop measurement technology are widely applied for ferromagnetic material evaluation.However the characterization ability of major hysteresis... In the nondestructive testing and evaluation area,magnetic major hysteresis loop measurement technology are widely applied for ferromagnetic material evaluation.However the characterization ability of major hysteresis loop measurement technology greatly varies as the evaluated target properties.To solve this limitation,magnetic minor hysteresis loops,which reflect the responses of ferromagnetic material magnetization in a systematic way,is recommend.Inspired by plenty of information carried by the minor loops,the sensitivity mapping technique was developed to achieve the highest sensitivity of minor-loop parameters to the nondestructively evaluated targets.In this study,for the first time,the sensitivity mapping technique is used to measure the tensile force in a steel strand and evaluate the effective case depth in induction-hardened steel rods.The method and procedures for the sensitivity mapping technique are given before experimental detection.The obtained experimental results indicate that the linear correlation between the induced voltage(or the magnetic induction intensity)and the tensile force(or effective case depth)exists at most of the locations in the cluster of minor loops.The obtained sensitivity maps can be used to optimize the applied magnetic field(or excitation current)and the analyzed locations at the minor loops for achieving the highest sensitivity.For the purpose of tensile force measurement,it is suggested that the strand should be firstly magnetized to the near-saturation state and then restored to the remanent state.In this way,the highest sensitivity is obtained as about 15.26 mV/kN.As for the induction-hardened steel rods,the highest sensitivity of magnetic induction intensity to the effective case depth occurs under low magnetic field conditions and the absolute value of the highest sensitivity is about 0.1110 T/mm.This indicates that if the highest sensitivity is required in the case depth evaluation,the induction-hardened steel rods are only required to be weakly magnetized.The proposed sensitivity mapping technique shows the good performance in the high-sensitivity evaluation of tensile force and case depth in ferromagnetic materials and its application scope can be extended to other nondestructive detection fields. 展开更多
关键词 Sensitivity mapping technique Magnetic minor hysteresis loop Tensile force Case depth
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The Comparison of Several 3D Digital Techniques Applied in Rockery Surveying and Mapping:A Case Study of North China University of Technology
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作者 QIN Ke WEN Ning 《Journal of Landscape Research》 2018年第5期28-34,共7页
By summarizing research status of traditional garden,the obstacles and difficulties of garden rockery research are analyzed,and the breakthroughs and advantages of 3D digital technique in garden rockery surveying and ... By summarizing research status of traditional garden,the obstacles and difficulties of garden rockery research are analyzed,and the breakthroughs and advantages of 3D digital technique in garden rockery surveying and mapping are introduced.The rockery in North China University of Technology is taken as the research object.Using many kinds of digital 3D techniques,3D scanning and modeling analysis of the rockery are conducted.Modeling result and accuracy of each technique are analyzed,and application prospect of 3D digital technique in rockery research of classical garden is explored. 展开更多
关键词 ROCKERY SURVEYING and mapping Digital technique
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Mapping the Dyke Swarms Emplaced within the Different Archean Cratons of the Indian Shield Using Google^(TM) Earth Images and Arc GIS^(TM) Techniques
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作者 Rajesh K.SRIVASTAVA Amiya K.SAMAL Richard E.ERNST 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期64-65,共2页
The Indian shield comprises a number of Archean–Paleoproterozoic cratonic blocks and predominantly Meso–Neoproterozoic mobile belts with Archean protoliths.All these ancient cratons were thought to be integral parts of
关键词 Earth Images and Arc GIS mapping the Dyke Swarms Emplaced within the Different Archean Cratons of the Indian Shield Using Google techniques Arc TM
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IsoVISoR: Towards 3D Mesoscale Brain Mapping of Large Mammals at Isotropic Sub-micron Resolution
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作者 Chao-Yu Yang Yan Shen +9 位作者 Xiaoyang Qi Lufeng Ding Yanyang Xiao Qingyuan Zhu Hao Wang Cheng Xu Pak-Ming Lau Pengcheng Zhou Fang Xu Guo-Qiang Bi 《Neuroscience Bulletin》 2025年第2期344-348,共5页
Dear Editor,The mammalian brain exhibits cross-scale complexity in neuronal morphology and connectivity,the study of which demands high-resolution morphological reconstruction of individual neurons across the entire b... Dear Editor,The mammalian brain exhibits cross-scale complexity in neuronal morphology and connectivity,the study of which demands high-resolution morphological reconstruction of individual neurons across the entire brain[1-4].Current commonly used approaches for such mesoscale brain mapping include two main types of three-dimensional fluorescence microscopy:the block-face methods,and the lightsheet-based methods[5,6].In general,the high imaging speed and light efficiency of light-sheet microscopy make it a suitable tool for high-throughput volumetric imaging,especially when combined with tissue-clearing techniques.However,large brain samples pose major challenges to this approach. 展开更多
关键词 brain mapping three dimensional fluorescence microscopy mesoscale brain mapping lightsheet based methods block face methods high throughput volumetric imaging tissue clearing techniques
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磁共振成像T_(2) mapping技术在三角纤维软骨复合体损伤诊断和评估中的应用进展
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作者 邢潇月 冯翼飞 +1 位作者 齐延红 栾海 《影像研究与医学应用》 2025年第16期4-6,共3页
三角纤维软骨复合体(TFCC)损伤是目前常见的腕关节软骨损伤类型,对患者的日常生活和工作影响比较明显,近年来发病率有逐渐升高的趋势。本综述旨在总结磁共振成像T_(2) mapping技术在诊断TFCC损伤中的应用进展,探讨其诊断TFCC损伤的优势... 三角纤维软骨复合体(TFCC)损伤是目前常见的腕关节软骨损伤类型,对患者的日常生活和工作影响比较明显,近年来发病率有逐渐升高的趋势。本综述旨在总结磁共振成像T_(2) mapping技术在诊断TFCC损伤中的应用进展,探讨其诊断TFCC损伤的优势与局限性,分析其诊断TFCC损伤局限性的应对措施,为TFCC损伤早期诊断和康复治疗提供更加准确的影像学依据。 展开更多
关键词 三角纤维软骨复合体损伤 磁共振成像 T_(2)mapping技术 定量磁共振成像技术
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微处理器在微区薄层电阻测试Mapping技术中的应用 被引量:2
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作者 孙新宇 王鑫 +3 位作者 孙以材 孟庆浩 孙冰 李福林 《半导体技术》 CAS CSCD 北大核心 1998年第2期18-23,共6页
利用微区薄层电阻测试的一种斜置四探针新方法,将扩散微区薄层电阻测试结果绘成全片的灰度图,这种Mapping技术十分有利于评价材料的质量。在测试过程中应用微处理器,可立即数字显示相应的测量电压及微区的薄层电阻,加快了计... 利用微区薄层电阻测试的一种斜置四探针新方法,将扩散微区薄层电阻测试结果绘成全片的灰度图,这种Mapping技术十分有利于评价材料的质量。在测试过程中应用微处理器,可立即数字显示相应的测量电压及微区的薄层电阻,加快了计算速度并有利于控制探针的合适位置。 展开更多
关键词 微区薄层电阻 探针技术 微处理器 测试 IC
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A Comprehensive Literature Review of AI-Driven Application Mapping and Scheduling Techniques for Network-on-Chip Systems
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作者 Naveed Ahmad Muhammad Kaleem +5 位作者 Mourad Elloumi Muhammad Azhar Mushtaq Ahlem Fatnassi Mohd Fazil Anas Bilal Abdulbasit A.Darem 《Computer Modeling in Engineering & Sciences》 2026年第1期118-155,共38页
Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance ... Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance and scalability,as current trends require the distribution of computation across network nodes/points.In this paper,we survey a large number of mapping and scheduling techniques designed for NoC architectures.This time,we concentrated on 3D systems.We take a systematic literature review approach to analyze existing methods across static,dynamic,hybrid,and machine-learning-based approaches,alongside preliminary AI-based dynamic models in recent works.We classify them into several main aspects covering power-aware mapping,fault tolerance,load-balancing,and adaptive for dynamic workloads.Also,we assess the efficacy of each method against performance parameters,such as latency,throughput,response time,and error rate.Key challenges,including energy efficiency,real-time adaptability,and reinforcement learning integration,are highlighted as well.To the best of our knowledge,this is one of the recent reviews that identifies both traditional and AI-based algorithms for mapping over a modern NoC,and opens research challenges.Finally,we provide directions for future work toward improved adaptability and scalability via lightweight learned models and hierarchical mapping frameworks. 展开更多
关键词 Application mapping mapping techniques network-on-chip system on chip optimisation
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微处理器在微区薄层电阻测试Mapping技术中的应用
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作者 孙新宇 孟庆浩 +2 位作者 孙以材 孙冰 李福林 《微电子技术》 1997年第3期55-62,共8页
本文利用微区薄层电阻测试的一种斜置四探针新方法,将扩散微区薄层电阻测试结果绘成全片的灰度图,这种微区薄层电阻测试Mapping技术十分有利于评价材料的质量。在测试过程中应用微处理器,可立即数字显示相应的测量电压及微区的薄层... 本文利用微区薄层电阻测试的一种斜置四探针新方法,将扩散微区薄层电阻测试结果绘成全片的灰度图,这种微区薄层电阻测试Mapping技术十分有利于评价材料的质量。在测试过程中应用微处理器,可立即数字显示相应的测量电压及微区的薄层电阻,加快了计算速度并有利于控制探针的合适位置。 展开更多
关键词 微区薄层电阻 探针技术 微处理器
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高分辨扫描电镜和X射线能谱Mapping技术研究碲矿物的成分和形态特征 被引量:10
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作者 胡勇平 于学峰 +1 位作者 郑林伟 郑遗凡 《岩矿测试》 CAS CSCD 北大核心 2015年第6期643-651,共9页
X射线能谱元素像分析技术(EDS-Mapping)可直接观察岩石光片中目标元素的分布特征。本文采用高分辨扫描电镜及配置的X射线能谱仪综合分析技术,对山东归来庄金矿中碲元素和其他元素的分布特征和组合规律进行研究,定性确定含碲矿物、形态... X射线能谱元素像分析技术(EDS-Mapping)可直接观察岩石光片中目标元素的分布特征。本文采用高分辨扫描电镜及配置的X射线能谱仪综合分析技术,对山东归来庄金矿中碲元素和其他元素的分布特征和组合规律进行研究,定性确定含碲矿物、形态特征及其与其他矿物间的空间关系。结果表明,研究区金矿中含碲矿物有棱角状碲金银矿、碲化铅等,以浸染状形貌他形镶嵌于主矿物他形石英和片状云母之间,颗粒大小从几微米到几百微米极不均匀。对典型含碲矿物的微区成分进一步精确测定,得到碲金银矿和碲化铅的化学式为Ag_(0.85)Au_(2.55)Te_6和Pb_(0.52)Te_(0.48),其中碲金银矿成分明显异常。本文研究为稀散分布微细矿物的成分、形态分布及与围岩关系建立了一套先进实用的表征方法,可为含碲金矿的综合利用提供技术支持。 展开更多
关键词 碲矿物 形态特征 扫描电镜 X射线能谱mapping技术
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Recognition of the major scattering sources on complex targets based on the high frequency radar cross section integrated calculation technique 被引量:5
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作者 黄敏杰 吕明云 +1 位作者 黄俊 武哲 《Journal of Shanghai University(English Edition)》 CAS 2009年第4期316-321,共6页
Based on the high frequency (HF) integrated radar cross section (RCS) calculation approach, a technique of detecting major scattering source is developed by using an appropriate arithmetic for scattering distribut... Based on the high frequency (HF) integrated radar cross section (RCS) calculation approach, a technique of detecting major scattering source is developed by using an appropriate arithmetic for scattering distribution and scattering source detection. For the perfect adaptability to targets and the HF of the HF integrated RCS calculation platform, this technique is suitable to solve large complex targets and has lower requirement to the target modeling. A comparison with the result of 2-D radar imaging confirms the accuracy and reliability of this technique in recognition of the major scattering source on complex targets. This technique provides the foundation for rapid integrated evaluation of the scattering performance and 3-D scattering model reconstruction of large complex targets. 展开更多
关键词 stealth technique radar cross section (RCS) scattering center scattering distribution map 2-dimension radar imaging
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A study on the early-warning technique concerning debris flow disasters 被引量:2
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作者 ZHOU Jinxing, WANG Lixian, XIE Baoyuan, FEI Shimin, WANG Xilin (1. Inst. of Forestry Research, Chinese Academy of Forestry Science, Beijing 100091, China 2. College of Resource & Environment, Beijing Forestry University, Beijing 100083, China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第3期363-370,共8页
According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destru... According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destructive strength, the debris flow torrent, high sand-carrying capacity flush flood torrent and common flush flood by the techniques. In this paper, the classification indices system and the quantitative rating methods are presented. Based on torrent classification, debris flow torrent hazard zone mapping techniques by which the debris flow disaster early-warning object can be ascertained accurately are identified. The key techniques of building the debris flow disaster neural network (NN) real time forecasting model are given detailed explanations in this paper, including the determination of neural node at the input layer, the output layer and the implicit layer, the construction of knowledge source and the initial weight value and so on. With this technique, the debris flow disaster real-time forecasting neural network model is built according to the rainfall features of the historical debris flow disasters, which includes multiple rain factors such as rainfall of the disaster day, the rainfall of 15 days before the disaster day, the maximal rate of rainfall in one hour and ten minutes. It can forecast the probability, critical rainfall of eruption of the debris flows, through the real-time rainfall monitoring or weather forecasting. Based on the torrent classification and hazard zone mapping, combined with rainfall monitoring in the rainy season and real-time forecasting models, the debris flow disaster early-warning system is built. In this system, the GIS technique, the advanced international software and hardware are applied, which makes the system’s performance steady with good expansibility. The system is a visual information system that serves management and decision-making, which can facilitate timely inspect of the variation of the torrent type and hazardous zone, the torrent management, the early-warning of disasters and the disaster reduction and prevention. 展开更多
关键词 debris flows disaster early-warning technique torrent classification mapping of the hazard zones
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磁共振T2-mapping定量成像评估兔急性肠系膜上动脉缺血小肠肠壁损伤的实验研究 被引量:1
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作者 陈梦莎 祖涵瑜 +5 位作者 钟晓飞 李敏敏 曹璋 韩慧婷 曹赫 姜兴岳 《磁共振成像》 CAS CSCD 北大核心 2022年第9期69-74,80,共7页
目的探讨MRI T2-mapping定量成像对监测和评估兔小肠急性肠系膜上动脉缺血(acute mesenteric ischemia,AMI)肠壁损伤的诊断价值。材料与方法将36只新西兰雄性白兔随机分为实验组(n=18)和对照组(n=18)。实验组行外科手术结扎第2~5支肠系... 目的探讨MRI T2-mapping定量成像对监测和评估兔小肠急性肠系膜上动脉缺血(acute mesenteric ischemia,AMI)肠壁损伤的诊断价值。材料与方法将36只新西兰雄性白兔随机分为实验组(n=18)和对照组(n=18)。实验组行外科手术结扎第2~5支肠系膜动脉弧形血管网以及相应肠管两端供血血管,随后分别于6个时间点(1 h、2 h、3 h、4 h、5 h、6 h)进行MR T2-mapping成像,每个时间点3只。扫描完成后分别对3只兔施行安乐死,取出肠系膜动脉弧形血管网第3分支所供应的肠管病理标本,评估小肠肠壁缺血损伤的严重程度和病理特征变化。对照组进行假手术,开腹不做结扎处理。各个时间点实验组与对照组定量数值的差异采用独立样本t检验,两组各时间点T2值的组内比较采用单因素方差分析,用高斯拟合模型对T2值与缺血时间点进行拟合,显示小肠缺血肠壁的演变规律,并用病理组织学进行相关验证。T2值与缺血时间点间的拟合方程为f(x)=145×exp{-[(x-3.475)/4.297]^(2)},拟合系数R^(2)=0.79。结果实验组6个时间点的T2值均高于对照组,差异有统计学意义(P<0.05)。实验组中T2_(3h)与T2_(1h)、T2_(2h)、T2_(5h)、T2_(6h)差异有统计学意义(P<0.05)。随着缺血时间的进展,T2值先升高后降低,前3 h病理表现以水肿炎细胞浸润为主,影像上缺血近3 h时的T2_(3h)值达到峰值(151.50±2.90)ms;缺血4 h时肠壁损伤到达肌层,此时出血面积大大增加,T2_(4h)值降为(142.50±4.30)ms,此后T2值持续降低。结论MRI T2-mapping定量成像有助于定量评估AMI小肠肠壁损伤,对于疾病的早期发现具有一定的优势,具有良好的临床应用前景。 展开更多
关键词 T2-mapping 定量技术 磁共振成像 急性肠系膜缺血 新西兰兔模型 小肠肠壁损伤
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MRI T2 mapping成像技术对腰椎间盘退行性变的诊断价值 被引量:4
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作者 胡君 李霞 《中国继续医学教育》 2018年第9期45-47,共3页
目的研究分析MRI T2 mapping成像技术对腰椎间盘退行性变的诊断价值。方法回顾性分析我院于2016年3月-2017年3月收治的80例因腰背部疼痛进行腰椎1.5TMRI检查的患者临床资料,80例患者均进行常规矢状位T_1W1、常规矢状位T_2W2、横断位T_2W... 目的研究分析MRI T2 mapping成像技术对腰椎间盘退行性变的诊断价值。方法回顾性分析我院于2016年3月-2017年3月收治的80例因腰背部疼痛进行腰椎1.5TMRI检查的患者临床资料,80例患者均进行常规矢状位T_1W1、常规矢状位T_2W2、横断位T_2W1扫描,也进行正中矢状位T2 mapping成像检查,依据Pfirrmann标准将350个腰椎间盘分级,测量纤维环(AF)前的T2值、髓核(NP)及纤维环(AF)后的T2值,对比分析腰椎间盘各分级的AF前缘的T2值、NP及AF后缘的T2值。选取20例腰背部疼痛患者进行间隔半年的MRI检查,比较这次检查和前次检查椎间盘T2值的不同。结果(1)有350个清晰图像的腰椎间盘,54个Ⅰ级,107个Ⅱ级,89个Ⅲ级,68个Ⅳ级,32个Ⅴ级。(2)腰椎间盘分级间的NP、AF前缘、AF后缘的T2值比较,部分存在差异,有统计学意义(P<0.05)。结论 MRI T2 mapping成像技术不仅仅可以定量评估腰椎间盘退行性变的程度,也能从髓核的T2值反映出不同分级椎间盘退行性变程度的差异性,可作为腰椎间盘退行性变的重要诊断的影像学依据。 展开更多
关键词 MRI T2 mapping成像技术 腰椎间盘退行性变 诊断
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3.0T磁共振T2×mapping成像技术定量评估膝关节骨性关节炎的临床价值及与WOMAC评分的相关性分析 被引量:38
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作者 王媛媛 王亮 +3 位作者 王云玲 郭辉 刘珺迪 王金英 《现代生物医学进展》 CAS 2021年第17期3256-3259,3309,共5页
目的:研究3.0 T磁共振T2×mapping成像技术定量评估膝关节骨性关节炎(OA)的临床价值及与西安大略和麦克马斯特大学骨关节炎指数(WOMAC)评分的相关性。方法:将我院于2017年4月~2019年12月期间收治的膝关节OA患者80例纳入研究。根据K-... 目的:研究3.0 T磁共振T2×mapping成像技术定量评估膝关节骨性关节炎(OA)的临床价值及与西安大略和麦克马斯特大学骨关节炎指数(WOMAC)评分的相关性。方法:将我院于2017年4月~2019年12月期间收治的膝关节OA患者80例纳入研究。根据K-L分级标准将膝关节OA患者分成轻度组(K-L分级为Ⅰ~Ⅱ级)32例,重度组(K-L分级为Ⅲ~Ⅴ级)48例。另取同期于我院进行体检的健康者30例作为对照组。所有受试者均接受3.0 T磁共振T2×mapping扫描,比较各组膝关节不同部位软骨T2值、WOMAC评分以及血清炎症因子水平,以Pearson相关性分析膝关节OA患者膝关节不同部位软骨T2值和WOMAC评分的关系。结果:重度组膝关节不同部位软骨T2值均高于轻度组以及对照组,且轻度组膝关节不同部位软骨T2值均高于对照组(均P<0.05)。重度组各项WOMAC评分及总分均高于轻度组以及对照组,且轻度组各项WOMAC评分及总分均高于对照组(均P<0.05)。经Pearson相关性分析发现:膝关节OA患者膝关节不同部位软骨T2值和各项WOMAC评分及总分均呈正相关(均P<0.05)。重度组血清白介素-1β(IL-1β)、白介素-18(IL-18)、肿瘤坏死因子α(TNF-α)均高于轻度组以及对照组,且轻度组血清IL-1β、IL-18、TNF-α均高于对照组(均P<0.05)。结论:3.0 T磁共振T2×mapping成像技术定量评估膝关节OA的临床价值较高,且患者膝关节不同部位软骨T2值与WOMAC评分密切相关。 展开更多
关键词 膝关节骨性关节炎 磁共振T2×mapping成像技术 西安大略和麦克马斯特大学骨关节炎指数 相关性
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Photonic generation of arbitrary waveforms based on incoherent wavelength-to-time mapping
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作者 董建绩 罗博文 +1 位作者 于源 张新亮 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期538-542,共5页
We demonstrate experimentally a radio frequency arbitrary waveform generator using the incoherent wavelength-to-time mapping technique. The system is implemented by amplitude modulation of a broadband optical resource... We demonstrate experimentally a radio frequency arbitrary waveform generator using the incoherent wavelength-to-time mapping technique. The system is implemented by amplitude modulation of a broadband optical resource whose spectrum is reshaped by a programmable optical pulse shaper and transmitted over a single mode fiber link. The shape of the generated waveform is controlled by the optical pulse shaper, and the fiber link introduces a certain group velocity delay to implement wavelength-to-time mapping. Assisted by the flexible optical pulse shaper, we obtain different shapes of optical waveforms, such as rectangle, triangle, and sawtooth waveforms. Furthermore, we also demonstrate ultra-wideband generation, such as Gaussian monocycle, doublet, and triplet waveforms, using the incoherent technique. 展开更多
关键词 arbitrary waveform generation ULTRA-WIDEBAND wavelength-to-time mapping incoherenttechnique arbitrary waveform generation ULTRA-WIDEBAND wavelength-to-time mapping incoherent technique
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Algorithm for solving a class of general mixed variational inequalities and nonexpansive mappings in Hilbert spaces
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作者 ZHAI Guangfu FAN Liya 《商丘师范学院学报》 CAS 2010年第3期18-22,共5页
This paper is devoted to study the convergence of a new class of generalized system for variational inequalities.The results presented in this paper modify and improve the recent result announced by Chang.[S.S.Chang,H... This paper is devoted to study the convergence of a new class of generalized system for variational inequalities.The results presented in this paper modify and improve the recent result announced by Chang.[S.S.Chang,H.W.Joseph Lee,Generalzed system for relaxed cocoercive variational inequalities in Hilerbert space,doi:10.1016/j.aml.2006.04.017]. 展开更多
关键词 H-monotone operator resolvent operator technique variational inclusion nonexpansive mapping
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