检索结果-南通市图书馆

quantitative analysis modeling for the Chem Cam spectral data based on laser-induced breakdown spectroscopy using convolutional neural network

引用

Plasma Science and Technology 2020年第11期22卷 81-90页

作者： Xueqiang CAO Li ZHANG Zhongchen WU Zongcheng LING Jialun LI Kaichen GUO School of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209People's Republic of China Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209People's Republic of China

Laser-induced breakdown spectroscopy(LIBS)has been applied to many fields for the quantitative analysis of diverse *** the prediction accuracy of LIBS regression models is still of great significance for the Mars exploration in the near *** this study,we explored the quantitative analysis of LIBS for the one-dimensional Chem Cam(an instrument containing a LIBS spectrometer and a Remote Micro-Imager)spectral data whose spectra are produced by the Chem Cam team using LIBS under the Mars-like atmospheric *** constructed a convolutional neural network(CNN)regression model with unified parameters for all oxides,which is efficient and *** that has the excellent capability of feature extraction can effectively overcome the chemical matrix effects that impede the prediction accuracy of regression ***,we explored the effects of four activation functions on the performance of the CNN *** results show that the CNN model with the hyperbolic tangent(tanh)function outperforms the CNN models with the other activation functions(the rectified linear unit function,the linear function and the Sigmoid function).Secondly,we compared the performance among the CNN models using different optimization *** CNN model with the stochastic gradient descent optimization and the initial learning rate?=?0.0005 achieves satisfactory performance compared to the other CNN ***,we compared the performance of the CNN model,the model based on support vector regression(SVR)and the model based on partial least square regression(PLSR).The results exhibit the CNN model is superior to the SVR model and the PLSR model for all *** on the above analysis,we conclude the CNN regression model can effectively improve the prediction accuracy of LIBS.

关键词： laser-induced breakdown spectroscopy convolutional neural network activation function optimization method quantitative analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

quantitative analysis of the main components in ceramic raw materials based on the desktop LIBS analyzer

引用

Plasma Science and Technology 2022年第8期24卷 46-54页

作者： Peng ZHANG Lanxiang SUN Haibin YU Peng ZENG State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016People's Republic of China Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016People's Republic of China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110016People's Republic of China

The concentrations of SiO,Al2O,KO,NaO,CaO,MgO,Fe2Oand TiO,and loss on ignition(L.O.I.) are the main inorganic components of geological *** of the eight oxides and *** also the main indicators of concern in the production of building *** analysis of the eight oxides and *** performed using fiber-laserbased laser-induced breakdown spectroscopy(LIBS).A combination of continuous background deduction,full width at half maximum(FWHM) intensity integral and spectral sum normalization was proposed for data *** the data processing combined the continuous background deduction,FWHM intensity integral and spectral sum normalization,the mean absolute errors(MAEs) of the calibration of L.O.I.,SiO,Al2O,KO,NaO,CaO,MgO,Fe2Oand TiOwas reduced from 2.03%,12.06%,4.84%,1.10%,0.69%,0.31%,0.11%,0.20%and 0.10% to 1.80%,9.48%,2.12%,0.36%,0.58%,0.11%,0.08%,0.19% and 0.05%,*** multivariate method was further introduced and discussed to improve the analysis *** MAEs of L.O.I.,SiO,Al2O,KO and NaO were further reduced to1.12%,2.07%,1.38%,0.35% and 0.43%,*** results show that the overall prediction error can meet the requirements for the production of building *** LIBS desktop analyzer has great potential in detection applications on geological samples.

关键词： laser-induced breakdown spectroscopy fiber laser quantitative analysis matrix effects geological samples

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

quantitative analysis of the Silk Moth＇s Chemical Plume Tracing Locomotion Using a Hierarchical Classification Method

引用

Journal of Bionic Engineering 2014年第2期11卷 268-281页

作者： Jouh Yeong Chew Daisuke Kurabayashi Department of Mechanical and Control Engineering Tokyo Institute of Technology 152-8552 Tokyo Japan

The silk moth （Bombyx mori） exhibits efficient Chemical Plume Tracing （CPT）, which is ideal for biomimetics. However, there is insufficient quantitative understanding of its CPT behavior. We propose a hierarchical classification method to segment its natural CPT locomotion and to build its inverse model for detecting stimulus input. This provides the basis for quantitative analysis. The Gaussian mixture model with expectation-maximization algorithm is used first for unsupervised classification to decompose CPT locomotion data into Gaussian density components that represent a set of quantified elemental motions. A heuristic behavioral rule is used to categorize these components to eliminate components that are descriptive of the same motion. Then, the echo state network is used for supervised classification to evaluate segmented elemental motions and to compare CPT locomotion among different moths. In this case, categorized elemental motions are used as the training data to estimate stimulus time. We successfully built the inverse CPT behavioral model of the silk moth to detect stimulus input with good accuracy. The quantitative analysis indicates that silk moths exhibit behavioral singularity and time dependency in their CPT locomotion, which is dominated by its singularity.

关键词： biomimetics recognition learning and adaptive systems chemical plume tracing quantitative analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

quantitative analysis of the intertube coupling effect on the photoluminescence characteristics of distinct(n,m)carbon nanotubes dispersed in solution

引用

Nano Research 2020年第4期13卷 1149-1155页

作者： Shilong Li Dehua Yang Jiaming Cui Yanchun Wang Xiaojun Wei Weiya Zhou Hiromichi Kataura Sishen Xie Huaping Liu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering College of Materials Science and Opto-Electronic TechnologyUniversity of Chinese Academy of SciencesBeijing 100049China Department of Physical Science University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory for Advanced Functional Materials and Structure Research Beijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China Nanomaterials Research Institute National Institute of Advanced Industrial Science and Technology(AIST)Tsukuba 305-8565Japan

In this work,we quantitatively studied the intertube coupling of different(n,m)-sorted semiconducting single-wall carbon nanotubes(SWCNTs)on their photoluminescence(PL)efficiencies by precisely tuning the ratio of(9,4)and(6,5)SWCNTs in the mixture.A significant decrease in the PL intensity of(9,4)SWCNTs was observed after mixing with(6,5)species when fixing the(9,4)concentration,which was confirmed to be caused by the absorption of incident photons and reabsorption of the emitted photons by the added(6,5)*** contrast,a similar decrease in the PL intensity of(6,5)SWCNTs was also observed after mixing with the larger-diameter(9,4)*** from that of(9,4)SWCNTs,the PL decrease of(6,5)SWCNTs was found to originate not only from photon absorption and reabsorption by the(9,4)species but also from one-way exciton energy transfer(EET)from the(6,5)SWCNTs to the larger-diameter(9,4)*** the experimental results and numerical simulations further demonstrated that increasing the concentration of mixed(9,4)SWCNTs would enhance the effects of photon absorption and reabsorption and EET on the PL intensity of(6,5)SWCNTs quantified by the decrease ratio of the(6,5)PL ***,the influence of EET was found to be always weaker than that of photon absorption and *** proposed that the observed EET between isolated SWCNTs in a surfactant solution is derived from their proximity due to Brownian motion.

关键词： single-wall carbon nanotubes photoluminescence intertube coupling quantitative analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

quantitative analysis and time-resolved characterization of simulated tokamak exhaust gas by laser-induced breakdown spectroscopy

引用

Plasma Science and Technology 2022年第4期24卷 188-197页

作者： Yaxiong HE Tao XU Yong ZHANG Chuan KE Yong ZHAO Shu LIU School of Physics and Energy Fujian Normal UniversityFuzhou 350117People's Republic of China Center for Superconducting and New Energy Research and Development Southwest Jiaotong UniversityChengdu 610031People's Republic of China Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering Fuzhou 350117People's Republic of China Shandong Dong Yi Optoelectronic Instrument Co. LtdYantai 264670People's Republic of China Technical Center for Industrial Product and Raw Material Inspection and Testing Shanghai CustomsShanghai 200135People's Republic of China

Tokamak exhaust is an important part of the deuterium-tritium fuel cycle system in fusion *** this work,we present a laser-induced breakdown spectroscopy(LIBS)-based method to monitor the gas compositions from the exhaust system in the tokamak ***(He),a main impurity in the exhaust gas,was mixed with hydrogen(H_(2))in different ratios through a self-designed gas distribution system,and sealed into a measurement chamber as a standard specimen.A 532 nm wavelength laser pulse with an output power of 100 mJ was used for plasma *** time-resolved LIBS is used to study the time evolution characteristics of the signal strength,signal-to-background ratio(SBR),signal-to-noise ratio(SNR)and relative standard deviation(RSD)of the helium and hydrogen characteristic *** Boltzmann twoline method was employed to estimate the plasma temperature of laser-induced plasma(LIP).The Stark-broadened profile of He I 587.56 nm was exploited to measure the electron *** these studies,an appropriate time was determined in which the low RSD%was consistent with the high signal-to-noise *** He I 587.56 nm and Hαemission lines with good signalto-noise ratio were extracted from the spectrum and used in the external standard method and internal standard method for quantitative *** test results for mixed gas showed that the average relative error of prediction was less than 11.15%,demonstrating the great potential of LIBS in detecting impurities in plasma exhaust gas.

关键词： exhaust gas plasma diagnostics LIBS quantitative analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

quantitative analysis results of CE-1 X-ray fluorescence spectrometer ground base experiment

引用

Chinese Physics C 2008年第1期32卷 24-27页

作者：崔兴柱王焕玉张承模陈勇张家宇彭文溪曹学蕾梁小华汪锦州高旻杨家卫 Insitute of High Energy Physics CAS

As the nearest celestial body to the earth, the moon has become a hot spot again in astronomy field recently. The element analysis is a much important subject in many lunar projects. Remote X-ray spectrometry plays an important role in the geochemical exploration of the solar bodies. Because of the quasi-vacuum atmosphere on the moon, which has no absorption of X-ray, the X-ray fluorescence analysis is an effective way to determine the elemental abundance of lunar surface. The CE-1 X-ray fluorescence spectrometer （CE-1/XFS） aims to map the major elemental compositions on the lunar surface. This paper describes a method for quantitative analysis of elemental compositions. A series of ground base experiments are done to examine the capability of XFS. The obtained results, which show a reasonable agreement with the certified values at a 30% uncertainty level for major elements, are presented.

关键词： X-ray fluorescence elemental abundance lunar surface quantitative analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

quantitative analysis of lead in aqueous solutions by ultrasonic nebulizer assisted laser induced breakdown spectroscopy

引用

Frontiers of physics 2016年第4期11卷 145-153页

作者：钟石磊卢渊孔伟金程凯郑荣儿 College of Physics Science Qingdao University Qingdao 266071 China Optics and Optoelectronics Laboratory Ocean University of China Qingdao 266100 China

In this study, an ultrasonic nebulizer unit was established to improve the quantitative analysis ability of laser-induced breakdown spectroscopy （LIBS） for liquid samples detection, using solutions of the heavy metal element Pb as an example. An analytical procedure was designed to guarantee the stability and repeatability of the LIBS signal. A series of experiments were carried out strictly according to the procedure. The experimental parameters were optimized based on studies of the pulse energy influence and temporal evolution of the emission features. The plasma temperature and electron density were calculated to confirm the LTE state of the plasma. Normalizing the intensities by background was demonstrated to be an appropriate method in this work. The linear range of this system for Pb analysis was confirmed over a concentration range of 0-4,150ppm by measuring 12 samples with different concentrations. The correlation coefficient of the fitted calibration curve was as high as 99.94% in the linear range, and the LOD of Pb was confirmed as 2.93ppm. Concentration prediction experiments were performed on a further six samples. The excellent quantitative ability of the system was demonstrated by comparison of the real and predicted concentrations of the samples. The lowest relative error was 0.043% and the highest was no more than 7.1%.

关键词： laser-induced breakdown spectroscopy (LIBS) ultrasonic nebulizer quantitative analysis water solution plasma diagnostics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

quantitative analysis of Meso-β-scale Convective Cells and Anvil Clouds over North China

引用

Advances in Atmospheric Sciences 2010年第5期27卷 1089-1098页

作者：林隐静王洪庆韩雷郑永光王玉 Department of Atmospheric Science School of Physics Peking University College of Information Science and Engineering Ocean University of China National Meteorological Center of CMA

This paper proposes several quantitative characteristics to study convective systems using observations from Doppler weather radars and geostationary satellites. Specifically, in order to measure the convective intensity of each system, a new index, named the ＂Convective Intensity Ratio＂（CIR）, is defined as the ratio between the area of strong radar echoes at the upper level and the size of the convective cell itself. Based on these quantitative characteristics, the evolution of convective cells, surface rainfall intensity, rainfall area and convectively generated anvil clouds can be studied, and the relationships between them can also be analyzed. After testing nine meso-β-scale convective systems over North China during 2006–2007, the results were as follows：（1） the CIR was highly correlated with surface rainfall intensity, and the correlation reached a maximum when the CIR led rainfall intensity by 6–30 mins. The maximum CIR could be at most ～30 mins before the maximum rainfall intensity. （2） Convective systems with larger maximum CIRs usually had colder cloud-tops. （3） The maximum area of anvil cloud appeared 0.5–1.5 h after rainfall intensity began to weaken. The maximum area of anvil cloud and the time lag between maximum rainfall intensity and the maximum area of anvil cloud both increased with the CIR.

关键词： convective cell anvil cloud quantitative analysis weather radar geostationary satellite

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

quantitative analysis of Moisture Effect on Black Soil Reflectance

引用

Pedosphere 2009年第4期19卷 532-540页

作者： LIU Huan-Jun ZHANG Yuan-Zhi ZHANG Xin-Le ZHANG Bai SONG Kai-Shan WANG Zong-Ming TANG Na College of Resources and Environmental Sciences Northeast Agricultural University Harbin 150030 (China) Institute of Space and Earth Information Science Chinese University of Hong Kong Hong Kong (China) Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changehun 130012 (China)

Several studies have demonstrated that soil reflectance decreases with increasing soil moisture content, or increases when the soil moisture reaches a certain content; however, there are few analyses on the quantitative relationship between soil reflectance and its moisture, especially in the case of black soils in northeast China. A new moisture adjusting method was developed to obtain soil reflectance with a smaller moisture interval to describe the quantitative relationship between soil reflectance and moisture. For the soil samples with moisture contents ranging from air-dry to saturated, the changes in soil reflectance with soil moisture can be depicted using a cubic equation. Both moisture threshold (MT) and moisture inflexion (MI) of soil reflectance can also be determined by the equation. When the moisture range was smaller than MT, soil reflectance can be simulated with a linear model. However, for samples with different soil organic matter (OM), the parameters of the linear model varied regularly with the OM content. Based on their relationship, the soil moisture can be estimated from soil reflectance in the black soil region.

关键词： black soil quantitative analysis remote sensing soil moisture spectral reflectance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

quantitative analysis of torrential rainfall associated with typhoon landfall:A case study of typhoon Haitang(2005)

引用

Progress in Natural Science:Materials International 2009年第1期19卷 55-63页

作者： Caijun Yue a,b,a Shanghai Typhoon Institute,the china Meterological Administration Shanghai 200030,China b Laboratory of Typhoon Forecast Technique/China Meterological Administration,Shangai 200030,China Shanghai Typhoon Institute the china Meterological Administration Shanghai 200030 China Laboratory of Typhoon Forecast Technique/China Meterological Administration Shangai 200030 China

A quantitative analysis of torrential rainfall associated with typhoon Haitang(2005) is carried out using a modified moist ageostrophic Q vector and data from Weather Research and Forecasting(WRF) model *** major factors determining the ascending motion associated with torrential rainfall have been studied:large-scale and convective condensational heating,topographic lifting and *** results show that the convective condensational heating plays a major role in the torrential rainfall process,and the large-scale condensational heating is secondary before the landfall of typhoon Haitang,and vice versa after the *** topographic lifting affects the formation of rainfall,whereas the topographic friction has important impacts on torrential rainfall after the *** rainfall amounts forced by the topographic friction and lifting have similar horizontal distributions,but the magnitudes of the former are 2-3 times larger than those of the *** rainfall amounts forced by topography(lifting and friction) and modified moist ageostrophic Q vector have different horizontal distributions,and the magnitudes of the former are 2-5 times larger than those of the *** analysis shows that the typhoon rainfall may be motivated by modified moist ageostrophic Q vector and enhanced further by the topographic effects.

关键词： Torrential rainfall Typhoon landfall Modi?ed moist ageostrophic Q vector Topography Condensational heating quantitative analysis

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：