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A novel optical emission spectroscopy method for diagnostics of contribution of different ionization mechanisms and flux of ions in different valences in discharge channel of a Hall thruster

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Chinese Journal of Aeronautics 2024年第4期37卷 294-307页

作者： Yanfei WANG Ximing ZHU Renqiu ZOU Shilin YAN junwei jia Zhongxi NING Daren YU School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Aerospace Plasma Propulsion Ministry of Industry and Information TechnologyHarbin 150001China Beijing Orient Institute of Measurement and Test Beijing 100094China Beijing Aerospace Long March Aircraft Research Institute Beijing 100076China

The mass application of Hall thrusters poses the need for a diagnostic method of ionization mechanism in the discharge channel to boost the iteration and optimization of thruster *** work presents an Optical Emission Spectroscopy (OES) method for diagnostics of the contribution of different ionization mechanisms and the flux of ions in different valences in the discharge channel of a Hall *** emission spectra in the discharge channel are analyzed by jointly utilizing a collisional-radiative model,an ionization-excitation model,and a flux-conservation *** is found that the intensities of some spectral lines can be converted into the reaction rates of collision processes,e.g.,electron-induced excitation and ionization *** latter can further be used to determine the evolutions of particle fluxes by utilizing the conservation law of *** novel method is demonstrated on a kilo-watt Hall *** evolutions of several parameters are determined using this method along the discharge channel,including the ionization rates of different mechanisms,particle fluxes,particle densities,and particle *** novel method can be further developed by being jointly utilized with spectral imaging and tomography techniques,enabling diagnostics of multi-dimensional distributions of the above-mentioned parameters in the discharge channel and near-field plume.

关键词： Hall thruster Optical emission spectroscopy Ionization mechanism Particle flux Divalent ion

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Accuracy improvement of calibration-free laser-induced breakdown spectroscopy

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Plasma Science and Technology 2019年第3期21卷 6-15页

作者： Hongbo FU Zhibo NI Huadong WANG junwei jia Fengzhong DONG Anhui Provincial Key Laboratory of Photonics Devices and Materials Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Key Laboratory of Environmental Optics & Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of Sciences University of Science and Technology of China

Calibration-free laser-induced breakdown spectroscopy can overcome the matrix effect and the huge application prospects of in situ and on-line measurement, so it has been studied and applied to many analytical samples by numerous researchers since it was first proposed in ***, its accuracy is always lower than other analytical techniques and traditional quantitative analysis methods of laser-induced breakdown spectroscopy. The goal of this paper is to review the improvement of accuracy in the experimental setup and spectral analysis,especially after 2010, but not limited to it. The main contents include the accurate measurement of spectral intensity, the spatial and temporal window of local thermodynamic equilibrium and the accurate calculation of temperature and electron density. Due to the requirement of one or more standard samples, the combination of standard samples and CF-LIBS is discussed as a separate section. Finally, a simple conclusion is offered to relevant researchers who want to use CF-LIBS for quantitative analysis.

关键词： CF-LIBS quantitative analysis accuracy self-absorption local thermodynamic equilibrium

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Big Data Analysis of Policy Coordination Paths Based on Latent Dirichlet Allocation Model and Fuzzy-Set Qualitative Comparative Analysis Method

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China Communications 2024年第12期21卷 309-325页

作者： He Nianchu jia junwei Xu jiangbo Wen Subin School of Economics and Management Nanjing University of Science and TechnologyNanjing 210094China School of Accounting Capital University of Economics and BusinessBeijing 100070China School of Accounting Nanjing Audit UniversityNanjing 211815China

The selection and coordinated application of government innovation policies are crucial for guiding the direction of enterprise innovation and unleashing their innovation ***,due to the lengthy,voluminous,complex,and unstructured nature of regional innovation policy texts,traditional policy classification methods often overlook the reality that these texts cover multiple policy topics,leading to lack of *** contrast,topic mining technology can handle large-scale textual data,overcoming challenges such as the abundance of policy content and difficulty in *** topic models can partition numerous policy texts into topics,they cannot analyze the interplay among policy topics and the impact of policy topic coordination on enterprise innovation in ***,we propose a big data analysis scheme for policy coordination paths based on the latent Dirichlet allocation(LDA)model and the fuzzyset qualitative comparative analysis(fsQCA)method by combining topic models with qualitative comparative *** LDA model was employed to derive the topic distribution of each document and the word distribution of each topic and enable automatic classi-fication through algorithms,providing reliable and objective textual classification ***,the fsQCA method was used to analyze the coordination paths and dynamic ***,experimental analysis was conducted using innovation policy text data from 31 provincial-level administrative regions in China from 2012 to 2021 as research *** results suggest that the proposed method effectively partitions innovation policy topics and analyzes the policy configuration,driving enterprise innovation in different regions.

关键词： fsQCA method innovation policy coordination LDA model

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Calibration curve and support vector regression methods applied for quantification of cement raw meal using laser-induced breakdown spectroscopy

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Plasma Science and Technology 2019年第3期21卷 23-30页

作者： junwei jia Hongbo FU Zongyu HOU Huadong WANG Zhibo NI Fengzhong DONG Anhui Provincial Key Laboratory of Photonic Devices and Materials Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences University of Science and Technology of China State Key Lab of Power Systems Department of Thermal Engineering Tsinghua-BP Clean Energy Center Tsinghua University

Laser-induced breakdown spectroscopy(LIBS) is a qualitative and quantitative analytical technique with great potential in the cement industrial analysis. Calibration curve(CC) and support vector regression(SVR) methods coupled with LIBS technology were applied for the quantification of three types of cement raw meal samples to compare their analytical concentration range and the ability to reduce matrix effects, respectively. To reduce the effects of fluctuations of the pulse-to-pulse, the unstable ablation and improve the reproducibility, all of the analysis line intensities were normalized on a per-detector basis. The prediction results of the elements of interest in the three types of samples, Ca, Si, Fe, Al, Mg, Na, K and Ti, were compared with the results of the wet chemical analysis. The average relative error(ARE),relative standard deviation(RSD) and root mean squared error of prediction(RMSEP) were employed to investigate and evaluate the prediction accuracy and stability of the two prediction methods. The maximum average ARE of the CC and SVR methods is 34.62% instead of 6.13%,RSD is 40.89% instead of 7.60% and RMSEP is 1.34% instead of 0.43%. The results show that SVR method can accurately analyze samples within a wider concentration range and reduce the matrix effects, and LIBS coupled with it for a rapid, stable and accurate quantification of different types of cement raw meal samples is promising.

关键词： cement raw meal calibration curves SVR LIBS

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Comparison of Model Checking Tools

Comparison of Model Checking Tools

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2012 2nd International Conference on Advanced Materials and Computer Science(ICAMCS 2012)

作者： Wei Gong junwei jia School of Control and Mechanical Engineering Tianjin Institute of Urban Construction School of Computer and Information Engineering Tianjin Institute of Urban Construction

Model Checking is a method for verification. The model will be checked until the specification of it is proved or disproved. With the rising complexity of big models, there are non-checkable cases, in which cases the problem can be analyzed by some models, for example, bounded Model Checking means to analyze the model until a defined time or depth. The verification happens automatically. The programs for doing this are called Model Checking Tools or Model Checker. Model Checking are used in both software and hardware verification. It is an inherent part of hardware verification, whereas it is less used in the software verification.

关键词： Model checking Mocha Prism NuSMV

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Detection of Al, Mg, Ca, and Zn in copper slag by LIBS combined with calibration curve and PLSR methods

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Plasma Science and Technology 2024年第2期26卷 132-138页

作者：贾军伟刘志峰潘从元薛骅骎 School of Mechanical Engineering Hefei University of TechnologyHefei 230009People's Republic of China Hefei GStar Intelligent Control Technical Co.Ltd. Hefei 230088People's Republic of China Anhui Industrial Combustion Monitoring Technology and Equipment Engineering Laboratory Hefei 230088People's Republic of China

The precise measurement of Al, Mg, Ca, and Zn composition in copper slag is crucial for effective process control of copper pyrometallurgy. In this study, a remote laser-induced breakdown spectroscopy(LIBS) system was utilized for the spectral analysis of copper slag samples at a distance of 2.5 m. The composition of copper slag was then analyzed using both the calibration curve(CC) method and the partial least squares regression(PLSR) analysis method based on the characteristic spectral intensity ratio. The performance of the two analysis methods was gauged through the determination coefficient(R^(2)), average relative error(ARE), root mean square error of calibration(RMSEC), and root mean square error of prediction(RMSEP). The results demonstrate that the PLSR method significantly improved both R^(2) for the calibration and test sets while reducing ARE, RMSEC, and RMSEP by 50% compared to the CC method. The results suggest that the combination of LIBS and PLSR is a viable approach for effectively detecting the elemental concentration in copper slag and holds potential for online detection of the elemental composition of high-temperature molten copper slag.

关键词： copper slag element remote LIBS PLSR

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基于WWW和分布对象技术的Browser/Server结构

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计算机工程 1998年第10期24卷 29-31,44页

作者：贾军渭华东计算技术研究所上海201800

首先讨论了当前WWW的不足，然后计分布式对象技术CORBA及ORB互操作进行了讨论．在此基础上，进行了将CORBA规范、Java语言与WWW技术相结合构成Browser／Server的尝试，并给出了在Browser／Server结构上构建信息系统的设想．

关键词： Browser/Server WWW 分布对象计算机网络

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Effect of Storage Time on Main Quality Indicators of Cotton

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Asian Agricultural Research 2023年第9期15卷 44-46页

作者： Yuxi GU Jin WANG Gang YUAN junwei jia Wei WANG Jinying CHEN Sinograin Chengdu Storage Research Institute Co. Ltd.Chengdu 610091China China Reserve Cotton Management Co. Ltd.Beijing 100000China

The quality indicators of cotton will change during *** the 5.89 million t of Xinjiang cotton from 2016 to 2021 as a sample,this paper analyzed the main fiber quality indicator data of warehouse-in and warehouse-out cotton for storage of 1.5,3.0,4.0,5.0,6.0,and 7.0 *** was found that the color grade of cotton decreased with the extension of storage *** cotton with storage time of 5.0 years mainly changed from white cotton grade 2 and white cotton grade 3 to light yellow stained cotton grade 1 and yellow stained cotton grade *** them,the increase of light yellow stained cotton grade 1 was the largest,and the change to yellow stained cotton grade 1 was the largest at the storage 6.0-7.0 *** addition,there were no significant changes in moisture regain,Micronaire value,upper half mean length,length uniformity index and fiber strength.

关键词： Cotton Storage time Fiber quality Quality indicator Color grade

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In vitro/in vivo studies of a novel anti-HIV self-assembly of ethyl ester of 5’-cholesteryl-phosphonyl zidovudine （ECPZ）

In vitro/in vivo studies of a novel anti-HIV self-assembly o...

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第十二届全国青年药学工作者最新科研成果交流会

作者： Lina Du junwei jia Pingju Ge Yu Wang Miao Li Xin Li Yiguang Jin Department of Pharmaceutical Chemistry Beijing Institute of Radiation Medicine Pharmaceutical College of Henan University Department of Pharmacy Chinese PLA General Hospital

An amphiphilic prodrug of anti-HTV nucleoside analogue,ethyl ester of 5’-cholesteryl-phosphonyl zidovudine（ECPZ） was *** aqueous suspension containing ECPZ self-assemblies was obtained through injecting the THF solution of ECPZ into water under *** interaction may be the driving force of molecular *** self-assemblies were nanoscale with-130 nm in size,and remained stable for a long *** of ECPZ self-assemblies were investigated in various environments including buffered solutions,plasma and tissue *** was degraded very slowly in neutral solutions,but rapidly degraded quickly in acid solution with the half-lives（tin） of less than 20 *** self-assemblies showed potent anti-HTV activity on MT4 cell *** the anti-HTV 50%effective concentration（EC50） of CPZ self-assemblies was 1 nM,only equal to 1/10 of AZT EC50 in the condition of ECPZ and HTV virus added into cells simultaneously,and 1/50 of AZT EC50 in the condition of ECPZ added into cells first,then added with *** was rapidly eliminated from circulation and distributed into the mononuclear phagocyte system（MPS） including liver,spleen and lung after bolus intravenous administration of ECPZ *** MPS-targeted effect and high anti-HTV activity of ECPZ self-assemblies make them become a promising self-assembled drug delivery system（SADDS） to eradicate HTV hidden in MPS.

关键词： anti-HIV cholesterol phosphorylation prodrugs self-assembly zidovudine(AZT)

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基于G函数的胜任素质识别模型管理研究

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科技管理研究 2011年第1期31卷 150-152页

作者：戎军安应民贾军伟兰州大学管理学院甘肃兰州730000

20世纪70年代兴起于美国人力资源管理领域的一个新概念——"胜任素质",给企业管理体系的创新带来了新的契机和方向。基于学者们对"胜任素质"多方面研究的基础,以胜任素质理论与胜任素质模型为视角,研究提出了基于G函数胜任素质识别模型... 详细信息

20世纪70年代兴起于美国人力资源管理领域的一个新概念——"胜任素质",给企业管理体系的创新带来了新的契机和方向。基于学者们对"胜任素质"多方面研究的基础,以胜任素质理论与胜任素质模型为视角,研究提出了基于G函数胜任素质识别模型,以探索企业招聘体系的创新和胜任能力识别的新思路和新方法。

关键词：胜任素质胜任素质模型 G函数

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