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文章速递Thermal behavior of materials in laser-assisted extreme manufacturing:Raman-based novel characterization 认领
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作者 Ridong Wang Shen Xu +1 位作者 Yanan Yue Xinwei Wang 《极端制造(英文)》 2020年第3期86-102,共17页
Laser-assisted manufacturing(LAM)is a technique that performs machining of materials using a laser heating process.During the process,temperatures can rise above over 2000°C.As a result,it is crucial to explore t... Laser-assisted manufacturing(LAM)is a technique that performs machining of materials using a laser heating process.During the process,temperatures can rise above over 2000°C.As a result,it is crucial to explore the thermal behavior of materials under such high temperatures to understand the physics behind LAM and provide feedback for manufacturing optimization.Raman spectroscopy,which is widely used for structure characterization,can provide a novel way to measure temperature during LAM.In this review,we discuss the mechanism of Raman-based temperature probing,its calibration,and sources of uncertainty/error,and how to control them.We critically review the Raman-based temperature measurement considering the spatial resolution under near-field optical heating and surface structure-induced asymmetries.As another critical aspect of Raman-based temperature measurement,temporal resolution is also reviewed to cover various ways of realizing ultrafast thermal probing.We conclude with a detailed outlook on Raman-based temperature probing in LAM and issues that need special attention. 展开更多
关键词 Raman spectroscopy temperature response spatial resolution temporal resolution ultrafast characterization
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浅谈CR检测中的分辨力与分辨率 认领
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作者 陈小明 石爱玲 +2 位作者 张军辉 吴志波 谭云华 《无损检测》 2020年第2期17-20,31共5页
现行CR检测标准中涉及多个有关分辨力和分辨率的术语,如分辨力、分辨率、图像分辨率、系统分辨率和扫描分辨率等,容易混淆。通过理论分析、试验和实际应用几个方面入手,阐明其间的内在联系和区别,以为从业人员学习与应用CR检测技术提供... 现行CR检测标准中涉及多个有关分辨力和分辨率的术语,如分辨力、分辨率、图像分辨率、系统分辨率和扫描分辨率等,容易混淆。通过理论分析、试验和实际应用几个方面入手,阐明其间的内在联系和区别,以为从业人员学习与应用CR检测技术提供帮助。 展开更多
关键词 CR检测 数字图像 分辨力 分辨率
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Utilization of Extrinsic Fabry-Perot Interferometers with Spectral Interferometric Interrogation for Microdisplacement Measurement 认领
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作者 Leonid Liokumovich Aleksandr Markvart Nikolai Ushakov 《电子科技学刊:英文版》 CAS CSCD 2020年第1期59-75,共17页
The paper presents a number of signal processing approaches for the spectral interferometric interrogation of extrinsic Fabry-Perot interferometers(EFPIs). The analysis of attainable microdisplacement resolution is pe... The paper presents a number of signal processing approaches for the spectral interferometric interrogation of extrinsic Fabry-Perot interferometers(EFPIs). The analysis of attainable microdisplacement resolution is performed and the analytical equations describing the dependence of resolution on parameters of the interrogation setup are derived. The efficiency of the proposed signal processing approaches and the validity of analytical derivations are supported by experiments. The proposed approaches allow the interrogation of up to four multiplexed sensors with attained resolution between 30 pm and 80 pm, up to three times improvement of microdisplacement resolution of a single sensor by means of using the reference interferometer and noisecompensating approach, and ability to register signals with frequencies up to 1 kHz in the case of 1 Hz spectrum acquisition rate. The proposed approaches can be used for various applications, including biomedical, industrial inspection, and others, amongst the microdisplacement measurement. 展开更多
关键词 Absolute MEASUREMENT dynamic MEASUREMENT Fabry-Perot interferometer LEAST-SQUARES methods optical fiber sensors RESOLUTION analysis RESOLUTION enhancement sensor multiplexing SPECTRAL interferometry
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文章速递Integrating cross-sensor high spatial resolution satellite images to detect subtle forest vegetation change in the Purple Mountains,a national scenic spot in Nanjing,China 认领
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作者 Fangyan Zhu Wenjuan Shen +2 位作者 Jiaojiao Diao Mingshi Li Guang Zheng 《林业研究:英文版》 SCIE CAS CSCD 2020年第5期1743-1758,共16页
Accurate information on the location and magnitude of vegetation change in scenic areas can guide the configuration of tourism facilities and the formulation of vegetation protection measures.High spatial resolution r... Accurate information on the location and magnitude of vegetation change in scenic areas can guide the configuration of tourism facilities and the formulation of vegetation protection measures.High spatial resolution remote sensing images can be used to detect subtle vegetation changes.The major objective of this study was to map and quantify forest vegetation changes in a national scenic location,the Purple Mountains of Nanjing,China,using multi-temporal cross-sensor high spatial resolution satellite images to identify the main drivers of the vegetation changes and provide a reference for sustainable management.We used Quickbird images acquired in 2004,IKONOS images acquired in 2009,and WorldView2 images acquired in 2015.Four pixel-based direct change detection methods including the normalized difference vegetation index difference method,multi-index integrated change analysis(MIICA),principal component analysis,and spectral gradient difference analysis were compared in terms of their change detection performances.Subsequently,the best pixel-based detection method in conjunction with object-oriented image analysis was used to extract subtle forest vegetation changes.An accuracy assessment using the stratified random sampling points was conducted to evaluate the performance of the change detection results.The results showed that the MIICA method was the best pixel-based change detection method.And the object-oriented MIICA with an overall accuracy of 0.907 and a kappa coefficient of 0.846 was superior to the pixel-based MIICA.From 2004 to 2009,areas of vegetation gain mainly occurred around the periphery of the study area,while areas of vegetation loss were observed in the interior and along the boundary of the study area due to construction activities,which contributed to 79%of the total area of vegetation loss.During 2009–2015,the greening initiatives around the construction areas increased the forest vegetation coverage,accounting for 84%of the total area of vegetation gain.In spite of this,vegetation loss occurred in the interior of the Purple Mountains due to infrastructure development that caused conversion from vegetation to impervious areas.We recommend that:(1)a local multi-agency team inspect and assess law enforcement regarding natural resource utilization;and(2)strengthen environmental awareness education. 展开更多
关键词 High spatial resolution satellite images Vegetation change Direct detection method Objectoriented Purple Mountains
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文章速递图像定量表达方式及相关单位设定 认领
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作者 周洁 王昕 《编辑学报》 CSSCI 北大核心 2020年第3期282-284,共3页
编辑加工图像处理方面稿件时,图像大小、图像尺寸、分辨率等表达方式往往容易产生歧义,且相关单位纷繁复杂、形式多样,给编辑规范化处理增加了难度。这里列举了编辑加工中可能遇到的几种表达方式及单位,具体有像素(pixel)、英文缩写px... 编辑加工图像处理方面稿件时,图像大小、图像尺寸、分辨率等表达方式往往容易产生歧义,且相关单位纷繁复杂、形式多样,给编辑规范化处理增加了难度。这里列举了编辑加工中可能遇到的几种表达方式及单位,具体有像素(pixel)、英文缩写px、分辨率ppi和dpi、长度单位英寸(inch),还有数字后面不带单位的情况。文章分别从性质设定、形式设定、表达设定、规范设定4个角度进行了讨论,以期规范图像定量表达方式及相关单位设定。 展开更多
关键词 编辑加工 图像大小 分辨率 像素 单位
文章速递简易荧光显微镜的制作及其在生物医学中的应用 认领
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作者 翟家振 张元龙 孔令杰 《物理实验》 北大核心 2020年第8期24-27,共4页
用光学元器件制作了简易荧光显微镜.采用笼式结构,荧光显微镜的系统结构更紧凑.采用背向探测方式,方便对小动物成像.采用不同放大倍率的物镜观察含荧光蛋白标记的脑组织切片,展示了所搭建荧光显微镜系统的性能,同时证实实际成像中需要... 用光学元器件制作了简易荧光显微镜.采用笼式结构,荧光显微镜的系统结构更紧凑.采用背向探测方式,方便对小动物成像.采用不同放大倍率的物镜观察含荧光蛋白标记的脑组织切片,展示了所搭建荧光显微镜系统的性能,同时证实实际成像中需要在成像视场与空间分辨率之间进行折中选择. 展开更多
关键词 荧光显微镜 生物成像 视场 分辨率
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冲击回波声频法用于铁路隧道衬砌质量检测 认领
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作者 姜勇 吴佳晔 +1 位作者 马永强 邓立 《铁道建筑》 北大核心 2020年第5期6-10,共5页
研究开发了冲击回波声频法这一新型无损检测方法,通过非接触式拾取冲击弹性波信号和高分辨力频谱分析,大大提高了对衬砌厚度、缺陷等的识别能力.百余座铁路隧道检测的实际应用及与地质雷达法等的对比验证结果表明,冲击回波声频法具有测... 研究开发了冲击回波声频法这一新型无损检测方法,通过非接触式拾取冲击弹性波信号和高分辨力频谱分析,大大提高了对衬砌厚度、缺陷等的识别能力.百余座铁路隧道检测的实际应用及与地质雷达法等的对比验证结果表明,冲击回波声频法具有测试精度高、分辨力强、测试效率较高等特点,非常适合于铁路隧道衬砌质量的检测. 展开更多
关键词 冲击回波声频法 隧道衬砌 无损检测 衬砌厚度 衬砌缺陷 分辨力
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Guided filter-based multi-scale super-resolution reconstruction 认领
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作者 Xiaomei Feng Jinjiang Li Zhen Hua 《智能技术学报》 2020年第2期128-140,共13页
The learning-based super-resolution reconstruction method inputs a low-resolution image into a network,and learns a non-linear mapping relationship between low-resolution and high-resolution through the network.In thi... The learning-based super-resolution reconstruction method inputs a low-resolution image into a network,and learns a non-linear mapping relationship between low-resolution and high-resolution through the network.In this study,the multi-scale super-resolution reconstruction network is used to fuse the effective features of different scale images,and the non-linear mapping between low resolution and high resolution is studied from coarse to fine to realise the end-to-end super-resolution reconstruction task.The loss of some features of the low-resolution image will negatively affect the quality of the reconstructed image.To solve the problem of incomplete image features in low-resolution,this study adopts the multi-scale super-resolution reconstruction method based on guided image filtering.The high-resolution image reconstructed by the multi-scale super-resolution network and the real high-resolution image are merged by the guide image filter to generate a new image,and the newly generated image is used for secondary training of the multi-scale super-resolution reconstruction network.The newly generated image effectively compensates for the details and texture information lost in the low-resolution image,thereby improving the effect of the super-resolution reconstructed image.Compared with the existing super-resolution reconstruction scheme,the accuracy and speed of super-resolution reconstruction are improved. 展开更多
关键词 RESOLUTION IMAGE NETWORK
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IMPACT OF VERTICAL RESOLUTION, MODEL TOP AND DATA ASSIMILATION ON WEATHER FORECASTING——A CASE STUDY 认领
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作者 邵旻 张宇 徐建军 《热带气象学报:英文版》 SCIE 2020年第1期71-81,共11页
The impacts of stratospheric initial conditions and vertical resolution on the stratosphere by raising the model top,refining the vertical resolution,and the assimilation of operationally available observations,includ... The impacts of stratospheric initial conditions and vertical resolution on the stratosphere by raising the model top,refining the vertical resolution,and the assimilation of operationally available observations,including conventional and satellite observations,on continental U.S.winter short-range weather forecasting,were investigated in this study.The initial and predicted wind and temperature profiles were analyzed against conventional observations.Generally,the initial wind and temperature bias profiles were better adjusted when a higher model top and refined vertical resolution were used.Negative impacts were also observed in both the initial wind and temperature profiles,over the lower troposphere.Different from the results by only raising the model top,the assimilation of operationally available observations led to significant improvements in both the troposphere and stratosphere initial conditions when a higher top was used.Predictions made with the adjusted stratospheric initial conditions and refined vertical resolutions showed generally better forecasting skill.The major improvements caused by raising the model top with refined vertical resolution,as well as those caused by data assimilation,were in both cases located in the tropopause and lower stratosphere.Negative impacts were also observed in the predicted near surface wind and lower-tropospheric temperature.These negative impacts were related to the uncertainties caused by more stratospheric information,as well as to some physical processes.A case study shows that when we raise the model top,put more vertical layers in stratosphere and apply data assimilation,the precipitation scores can be slightly improved.However,more analysis is needed due to uncertainties brought by data assimilation. 展开更多
关键词 WRF model vertical resolution model top data assimilation weather forecast
Cross-cumulant enhanced radiality nanoscopy for multicolor superresolution subcellular imaging 认领
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作者 ZHIPING ZENG JING MA CANHUA Xu 《光子学研究:英文版》 SCIE EI CSCD 2020年第6期893-898,共6页
Fluorescence fuctuation-based superresolution techniques can achieve fast superresolution imaging on a cost-effective wide-field platform at a low light level with reduced phototoxicity.However,the current methods exh... Fluorescence fuctuation-based superresolution techniques can achieve fast superresolution imaging on a cost-effective wide-field platform at a low light level with reduced phototoxicity.However,the current methods exhibit certain imaging deficiencies that misinterpret nanoscale features reconstructed from fluctuating image scquences,thus degrading the superresolution imaging quality and performance.Here we propose Cross-cumulant enhanced radiality nanoscopy(CERN),which employs cross cumulant analysis in tandem with radiality processing.We demonstrated that CERN can significantly improve the spatial resolution at a low light level while eliminating the misinterpretations of nanoscale features of the existing fluctuation-based superresolution methods.In the experiment,we further verified the superior performance of CERN over the current methods through performing multicolor superresolution imaging of subcellular microtubule networks and clathrin-coated pits as well as the high-precision reconstruction of densely packed RNA transcripts. 展开更多
关键词 RADIAL RESOLUTION packed
基于损失函数的采样策略研究 认领
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作者 纪文昕 赵雷 张晓林 《信息通信》 2020年第5期5-9,共5页
使用ADC芯片进行数据转换时,可在过采样条件下用算术平均滤波法降噪,但该算法在噪声RMS值可变系统中难以兼顾效率和降噪效果。基于损失函数对算术平均滤波法做出了改进,将平均次数与噪声RMS和分辨率(信噪比)相对应,再根据分辨率(信噪比... 使用ADC芯片进行数据转换时,可在过采样条件下用算术平均滤波法降噪,但该算法在噪声RMS值可变系统中难以兼顾效率和降噪效果。基于损失函数对算术平均滤波法做出了改进,将平均次数与噪声RMS和分辨率(信噪比)相对应,再根据分辨率(信噪比)要求,对不同的噪声RMS值(信噪比)使用不同的过采样次数。理论分析和实测结果表明,该方法可在更大噪声RMS值变化范围内获得更好的降噪结果和更高的采样效率。 展开更多
关键词 损失函数 采样策略 分辨率
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VHF波段星载SAR系统电离层效应仿真研究 认领
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作者 姚佰栋 时晶晶 +2 位作者 盛磊 赵宁 葛家龙 《空军预警学院学报》 2020年第2期84-87,共4页
为研究VHF波段星载合成孔径雷达(SAR)系统,分析了雷达中心频率、信号带宽、电离层总电子含量(TEC)以及闪烁强度等因素对于VHF波段星载SAR成像的影响,并进行了仿真研究.仿真结果表明,在空间电离层中传播时,VHF波段星载SAR的距离向分辨率... 为研究VHF波段星载合成孔径雷达(SAR)系统,分析了雷达中心频率、信号带宽、电离层总电子含量(TEC)以及闪烁强度等因素对于VHF波段星载SAR成像的影响,并进行了仿真研究.仿真结果表明,在空间电离层中传播时,VHF波段星载SAR的距离向分辨率与雷达中心频率、信号带宽以及传播路径上的电离层TEC大小密切相关,同时由于时延的影响,还会导致SAR距离向图像发生移位,造成定位精度下降;方位向分辨率受闪烁效应影响严重,当处于弱闪烁或中等闪烁时,旁瓣抬升明显,且产生微小的移位,当处于强闪烁时,方位向分辨率明显降低,甚至无法成像. 展开更多
关键词 电离层 VHF波段 星载合成孔径雷达 分辨率 电离层总电子含量
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Improved spatial filtering velocimetry and its application in granular flow measurement 认领
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作者 孔平 王必得 +2 位作者 王蓬 Zivkovic V 张建青 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第7期300-307,共8页
Spatial filtering velocimetry(SFV)has the advantages of simple structure,good stability,and wide applications.However,the traditional linear CCD-based SFV method requires an accurate angle between the direction of lin... Spatial filtering velocimetry(SFV)has the advantages of simple structure,good stability,and wide applications.However,the traditional linear CCD-based SFV method requires an accurate angle between the direction of linear CCD and the direction of moving object,so it is not suitable for measuring a complex flow field or two-dimensional speed in a granular media.In this paper,a new extension of spatial filtering method(SFM)based on high speed array CCD camera is proposed as simple and effective technique for measuring two-dimensional speed field of granular media.In particular,we analyzed the resolution and range of array CCD-based SFV so that the reader can clarify the application scene of this method.This method has a particular advantage for using orthogonal measurement to avoid the angle measurement,which were problematic when using linear CCD to measure the movement.Finally,the end-wall effects of the granular flow in rotating drum is studied with different experimental conditions by using this improved technique. 展开更多
关键词 spatial filtering velocimetry array CCD end-wall effects RESOLUTION
全球250 m反照率产品算法及验证 认领
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作者 陆彦蓉 刘强 +4 位作者 李霞 李秀红 刘璐 肖洒 孙美莹 《地球信息科学学报》 CSCD 北大核心 2020年第2期328-335,共8页
反照率是反映地表能量平衡的重要参数之一,也被运用于全球变化与天气预测研究中。为了更好地获取反照率产品,学者们在不断地更新反照率产品和提出新算法。本文主要是在1 km分辨率的全球陆表特征参量(GLASS)反照率产品基础上进一步开发25... 反照率是反映地表能量平衡的重要参数之一,也被运用于全球变化与天气预测研究中。为了更好地获取反照率产品,学者们在不断地更新反照率产品和提出新算法。本文主要是在1 km分辨率的全球陆表特征参量(GLASS)反照率产品基础上进一步开发250 m反照率产品。算法思路是利用中分辨率成像光谱仪(MODIS)传感器的250 m分辨率波段提供纹理信息,利用成熟的GLASS 1 km反照率产品提供均值信息,进行数据融合,实现GLASS 1 km反照率产品的降尺度。相比于GLASS 1km反照率产品,250 m产品首先展现出更为丰富的空间细节信息,并且在与地面站点观测数据(北美地区站点数据)直接对比中显示出稍高的验证精度,GLASS 1 km产品的验证精度为0.0257,而250 m产品验证精度0.0235。最后,以北京市为例,基于2003-2013年的产品分析了北京市周边反照率及其变化趋势的空间分布,可以看到250 m反照率产品视觉效果更好,相比于1 km产品能够揭示反照率变化趋势的更多空间细节信息。分析表明,在北京城市化进程中,由于加大了城市绿化,主城区反照率总体呈降低趋势。 展开更多
关键词 地表反照率 GLASS MODIS 算法 验证 分辨率 空间细节
A Survey on Blocking Technology of Entity Resolution 认领
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作者 Bo-Han Li Yi Liu +2 位作者 An-Man Zhang Wen-Huan Wang Shuo Wan 《计算机科学技术学报:英文版》 SCIE EI CSCD 2020年第4期769-793,共25页
Entity resolution(ER)is a significant task in data integration,which aims to detect all entity profiles that correspond to the same real-world entity.Due to its inherently quadratic complexity,blocking was proposed to... Entity resolution(ER)is a significant task in data integration,which aims to detect all entity profiles that correspond to the same real-world entity.Due to its inherently quadratic complexity,blocking was proposed to ameliorate ER,and it offers an approximate solution which clusters similar entity profiles into blocks so that it suffices to perform pair-wise comparisons inside each block in order to reduce the computational cost of ER.This paper presents a comprehensive survey on existing blocking technologies.We summarize and analyze all classic blocking methods with emphasis on different blocking construction and optimization techniques.We find that traditional blocking ER methods which depend on the fixed schema may not work in the context of highly heterogeneous information spaces.How to use schema information flexibly is of great significance to efficiently process data with the new features of this era.Machine learning is an important tool for ER,but end-to-end and efficient machine learning methods still need to be explored.We also sum up and provide the most promising trend for future work from the directions of real-time blocking ER,incremental blocking ER,deep learning with ER,etc. 展开更多
关键词 BLOCKING construction BLOCKING OPTIMIZATION data LINKAGE ENTITY RESOLUTION
Software-aided detection and structural characterization of cyclic peptide metabolites in biological matrix by high-resolution mass spectrometry 认领
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作者 Ming Yao Tingting Cai +3 位作者 Eva Duchoslav Li Ma Xu Guo Mingshe Zhu 《药物分析学报:英文版》 SCIE CAS CSCD 2020年第3期240-246,共7页
Compared to their linear counterparts,cyclic peptides show better biological activities,such as antibacterial,immunosuppressive,and anti-tumor activities,and pharmaceutical properties due to their conformational rigid... Compared to their linear counterparts,cyclic peptides show better biological activities,such as antibacterial,immunosuppressive,and anti-tumor activities,and pharmaceutical properties due to their conformational rigidity.However,cyclic peptides could form numerous putative metabolites from potential hydrolytic cleavages and their fragments are very difficult to interpret.These characteristics pose a great challenge when analyzing metabolites of cyclic peptides by mass spectrometry.This study was to assess and apply a software-aided analytical workflow for the detection and structural characterization of cyclic peptide metabolites.Insulin and atrial natriuretic peptide(ANP)as model cyclic peptides were incubated with trypsin/chymotrypsin and/or rat liver S9,followed by data acquisition using TripleTOF?5600.Resultant full-scan MS and MS/MS datasets were automatically processed through a combination of targeted and untargeted peak finding strategies.MS/MS spectra of predicted metabolites were interrogated against putative metabolite sequences,in light of a,b,y and internal fragment series.The resulting fragment assignments led to the confirmation and ranking of the metabolite sequences and identification of metabolic modification.As a result,29 metabolites with linear or cyclic structures were detected in the insulin incubation with the hydrolytic enzymes.Sequences of twenty insulin metabolites were further determined,which were consistent with the hydrolytic sites of these enzymes.In the same manner,multiple metabolites of insulin and ANP formed in rat liver S9 incubation were detected and structurally characterized,some of which have not been previously reported.The results demonstrated the utility of software-aided data processing tool in detection and identification of cyclic peptide metabolites. 展开更多
关键词 Atrial natriuretic peptide Metabolism of cyclic peptide High resolution mass spectrometry INSULIN Software-aided data processing
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一种电解镁原料制备过程中的氯化氢深解析技术 认领
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作者 马芬兰 李鹏业 +1 位作者 齐春全 张志云 《世界有色金属》 2020年第7期19-20,共2页
本文主要介绍了一种电解镁生产原料中的氯化氢解析技术.在卤水生产无水氯化镁过程中,以系统废液中自带的氯化镁为萃取剂进行氯化氢深解析的技术,是全球首例成功应用的技术.
关键词 氯化镁萃取剂 解析率
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Influence of Sea Surface Temperature on Outbreak of Ulva prolifera in the Southern Yellow Sea,China 认领
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作者 ZHANG Guangzong WU Mengquan +5 位作者 ZHANG Anding XING Qianguo ZHOU Min ZHAO Deheng SONGXiaodong YU Zhilu 《中国地理科学:英文版》 SCIE CSCD 2020年第4期631-642,共12页
In this study,using Moderate Resolution Imaging Spectroradiometer(MODIS)satellite images and environmental satellite CCD images,the spatio-temporal distribution of Ulva prolifera in the southern Yellow Sea during the ... In this study,using Moderate Resolution Imaging Spectroradiometer(MODIS)satellite images and environmental satellite CCD images,the spatio-temporal distribution of Ulva prolifera in the southern Yellow Sea during the period of 2011–2018 was extracted and combined with MODIS Level3 Photosynthetically Active Radiation(PAR)product data and Earth System Research Laboratory(ESRL)Sea Surface Temperature(SST)data to analyze their influences on the growth and outbreak of Ulva prolifera.The following conclusions were drawn:1)comprehensive analysis of Ulva prolifera distribution during the eight-year period revealed that the coverage area of Ulva prolifera typically exhibited a gradually increasing trend.The coverage area of Ulva prolifera reached a maximum of approximately 1714.21 km^2 during the eight-year period in late June 2015.The area affected by Ulva prolifera fluctuated.In mid-July 2014,the area affected by Ulva prolifera reached a maximum of approximately 39020.63 km^2.2)The average growth rate of Ulva prolifera was positive in May and June but negative in July.During the outbreak of Ulva prolifera,the SST in the southern Yellow Sea tended to increase each month.The SST anomaly and average growth rate of Ulva prolifera were positively correlated in May(R^2=0.62),but not significantly correlated in June or July.3)The variation trends of PAR and SST were approximately the same,and the PAR during this time period maintained a range of 40–50 mol/(m^2·d),providing sufficient illumination for the growth and outbreak of Ulva prolifera.In addition,the abundant nutrients and suitable temperature in the sea area near northern Jiangsu shoal resulted in a high growth rate of Ulva prolifera in May.In summary,the outbreak of Ulva prolifera was closely related to the environmental factors including SST,nutrients,and PAR.Sufficient nutrients and suitable temperatures resulted in a fast growth rate of Ulva prolifera.However,under poor nutrient conditions,even more suitable temperatures were not sufficient to trigger an outbr 展开更多
关键词 Sea Surface Temperature(SST) Photosynthetically Active Radiation(PAR) Ulva prolifera MODIS(Moderate Resolution Imaging Spectroradiometer) the southern Yellow Sea
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Atomic level deposition to extend Moore’s law and beyond 认领
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作者 Rong Chen Yi-Cheng Li +2 位作者 Jia-Ming Cai Kun Cao Han-Bo-Ram Lee 《极端制造(英文)》 2020年第2期29-52,共24页
In the past decades,Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors down to 7 nm.As transistors further downscaling to smaller sizes,the law reaches its limitatio... In the past decades,Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors down to 7 nm.As transistors further downscaling to smaller sizes,the law reaches its limitation,and the increase of transistors density on the chip decelerates.Up to now,extreme ultraviolet lithography has been used in some key steps,and it is facing alignment precision and high costs for high-volume manufacturing.Meanwhile,the introduction of new materials and 3D complex structures brings serious challenges for top-down methods.Thus,bottom-up schemes are believed to be necessary methods combined with the top-down processes.In this article,atomic level deposition methods are reviewed and categorized to extend Moore’s law and beyond.Firstly,the deposition brings lateral angstrom resolution to the vertical direction as well as top-down etching,such as double patterning,transfer of nanowires,deposition of nanotubes,and so on.Secondly,various template-assisted selective deposition methods including dielectric templates,inhibitors and correction steps have been utilized for the alignment of 3D complex structures.Higher resolution can be achieved by inherently selective deposition,and the underlying selective mechanism is discussed.Finally,the requirements for higher precision and efficiency manufacturing are also discussed,including the equipment,integration processes,scale-up issues,etc.The article reviews low dimensional manufacturing and integration of 3D complex structures for the extension of Moore’s law in semiconductor fields,and emerging fields including but not limited to energy,catalysis,sensor and biomedicals. 展开更多
关键词 Moore’s law atomic level deposition high resolution selective deposition ALIGNMENT
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基于混合部件模型改进的人体姿态估计 认领
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作者 薛涛 《信息与电脑》 2020年第10期116-118,共3页
很多研究报告表明,目前一种可行且十分有效的方法是利用混合部件模型进行基于人体姿态的图像估计研究工作。但是,目前已提出的类似方法中都存在一些未考虑到的缺陷和问题。为更好地弥补研究中的一些缺陷,笔者在混合部件模型的基础上进... 很多研究报告表明,目前一种可行且十分有效的方法是利用混合部件模型进行基于人体姿态的图像估计研究工作。但是,目前已提出的类似方法中都存在一些未考虑到的缺陷和问题。为更好地弥补研究中的一些缺陷,笔者在混合部件模型的基础上进行改进,提出了通过核心部件进行解析来达到加速解析的目的。具体为提取出部分核心部件来减少待处理图像的有效分辨率数量,根据实验结果,可以证明改进后的人体姿态识别方法在仍具备较高识别性能的基础上,解析速度明显加快。 展开更多
关键词 混合部件 姿态识别 核心部件 分辨率
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