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High Voltage 2022年第4期7卷 652-665页

作者： Simone Vincenzo Suraci Sandrine Amat Lea Hippolyte Astrid Malechaux Davide Fabiani Claire Le Gall Océane Juan Nathalie Dupuy LIMES Department of ElectricalElectronic and Information EngineeringUniversity of BolognaBolognaItaly Aix Marseille University Avignon UniversitéCNRSMarseilleFrance Institut de Radioprotection et de Sûreté Nucléaire MarseilleFrance

The evolution of properties of crosslinked polyethylene(XLPE)-based insulating mate-rials under radio-chemical ageing conditions is presented and discussed.In total,seven different polymer compounds were tested,characterised by an increasing quantity of additives,for example,antioxidants(AOs)and fillers as flame retardants.Samples were analysed using different testing techniques,that is,Fourier Transform Infra-Red and dielectric spectroscopy.This allowed a broad characterisation of the polymer,bringing to good correlations between the arising of new chemical groups caused by ageing and the modifications on the complex permittivity.Phenol-based AOs are found to be the most efficient in terms of protection against oxidation.On the contrary,flame retardants are concluded not to have any impact on the material ageing.Acquired data were then treated using the Principal component analysis.The data treatment successfully distinguished the material composition(with and without additives)and the ageing environments.The results confirm the relevance of this analysis in understanding the impact of irradiation on the chemical and functional properties of the polymer materials studied.

关键词： component Principal bringing

Retrieval of aerosol optical constants from angular light-scattering measurement signals using Principal component analysis approach

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Particuology 2019年第2期17卷 210-218页

作者： Zhenzong He Junkui Mao Xingsi Han Hao Wang Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

An angular light-scattering measurement (ALSM) method combined with the probability density function-bmsed ant colony optimization algorithm (PDF-ACO) is proposed for retrieval of aerosol optical constants. An optimal measurement angle selection method using a Principal component analysis (PCA) approach is developed to improve retrieval accuracy. Results indicate that optimized angle selection can ensure retrieval accuracy. The aerosol optical constants over Beijing, China, which are available from the Aerosol Robotic Network (AERONET), are then rec on structed. The ALSM method's con vergence properties are also studied via comparison w让h those of the light reflection-transmittance measurement (LRTM) method. Results retrieved using the ALSM method show better convergence speed and accuracy than those retrieved using the LRTM method because the ALSM method does not require solution of the radiative transfer equation and allows more useful signals to be obtained. Additionally, the inverse accuracy of the refractive index results is better than that of the absorption index results;this is attributed to differences between the monodromic characteristics of the refractive index and absorption index retrieval results. All results confirm that the combination of the ALSM method w让h the PDF-ACO algorithm and the optimal measurement angle selection method provides effective and reliable aerosol optical constant reconstructio n.

关键词： Angular light-scattering measurement method Aerosol optical constant Ant colony optimization algorithm Principal comp orient analysis Inverse radiation problem

Crustal structure study based on Principal component analysis of receiver functions

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Science China Earth Sciences 2019年第7期62卷 1110-1124页

作者： Jianyong ZHANG Ling CHEN Xu WANG State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences

The receiver function(RF) technique is an effective method for studying crustal structure. For a single station, the average 1-D crustal structure is usually derived by stacking the radial RFs from all back-azimuths, whereas structural variations(such as dipping discontinuities or anisotropy) can be constrained through analysis of waveform dependence on the backazimuth of both the radial and tangential RFs. However, it is often difficult to directly extract information about structural variations from the waveform of RF, due to the common presence of noise in real data. In this study, we proposed a new method to derive structural variation information for individual stations by applying Principal component analysis(PCA) to RFs sorted by back-azimuth. In this method(termed as RF-PCA), a set of Principal components(PCs), which are uncorrelated with each other and reflect different characteristics of the RF data, were extracted and utilized separately to reconstruct new RFs. Synthetic tests show that the first PC of the radial RFs contains the average structural information of the crust beneath the corresponding station, and the second PC of the radial RFs and the first PC of the tangential RFs both reflect the variations of the crustal structure. Our synthetic modeling results indicate that the new RF-PCA method is valid for a variety of synthetic models with intra-crustal dipping discontinuities and/or anisotropy. We applied this method to the real data from a broadband temporary seismic station(s233) in the central part of the Sichuan Basin. The results suggest that the RF data can be best explained by the presence of two nearly parallel dipping discontinuities within the crust. Combining with previous logging data, seismic exploration and deep sounding observations, we interpret the shallow dipping discontinuity as the top boundary of the Precambrian crystalline basement of the Sichuan Basin and the deep one corresponding to the Conrad interface between the upper and lower crust, consistent with the geological f

关键词： Principal component analysis Receiver function Crustal structure Dipping discontinuity Anisotropy Sichuan Basin

Effects of granulation process variables on the physical properties of dosage forms by combination of experimental design and Principal component analysis

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Asian Journal of Pharmaceutical Sciences 2019年第3期14卷 287-304页

作者： Prakash Thapa Du Hyung Choi Min Soo Kim Seong Hoon Jeong College of Pharmacy Dongguk UniversityGyeonggi10326Republic of Korea Department of Pharmaceutical Engineering Inje UniversityGyeongnam50834Republic of Korea College of Pharmacy Pusan National UniversityBusan46241Republic of Korea

The current study was to understand how process variables of high shear wet granulations affect physical properties of granules and tablets. The knowledge gained was intended to be used for Quality-by-Design based process design and optimization. The variables were selected based on the risk assessment as impeller speed, liquid addition rate, and wet massing time. Formulation compositions were kept constant to minimize their influence on granules properties. Multiple linear regression models were built providing understanding of the impact of each variable on granule hardness, Carr’s index, tablet tensile strength, surface mean diameter of granules, and compression behavior. The experimental results showed that the impact of impeller speed was more dominant compared to wet massing time and water addition rate. The results also revealed that quality of granules and tablets could be optimized by adjusting specific process variables(impeller speed 1193 rpm, water spray rate 3.7 ml/min, and wet massing time 2.84 min). Overall desirability was 0.84 suggesting that the response values were closer to the target one. The SEM image of granules showed that spherical and smooth granules produced at higher impeller speed, whereas rough and irregular shape granules at lower speed. Moreover, multivariate data analysis demonstrated that impeller speed and massing time had strong correlation with the granule and tablet properties. In overall, the combined experimental design and Principal component analysis approach allowed to better understand the correlation between process variables and granules and tablet attributes.

关键词： Experimental design Principal component analysis High shear granulation Process parameter

Impact of parameter fluctuations on the performance of ethanol precipitation in production of Re Du Ning Injections, based on HPLC fingerprints and Principal component analysis

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Chinese Journal of Natural Medicines 2016年第1期14卷 73-80页

作者： SUN Li-Qiong WANG Shu-Yao LI Yan-Jing WANG Yong-Xiang WANG Zhen-Zhong HUANG Wen-Zhe WANG Yue-Sheng BI Yu-An DING Gang XIAO Wei State Key Laboratory of New-tech for Chinese Medicine Pharmaceutical Process Lianyungang 222001 China Jiangsu Kanion Pharmaceutical Co. Ltd. Lianyungang 222001 China

The present study was designed to determine the relationships between the performance of ethanol precipitation and seven process parameters in the ethanol precipitation process of Re Du Ning Injections,including concentrate density,concentrate temperature,ethanol content,flow rate and stir rate in the addition of ethanol,precipitation time,and precipitation temperature.Under the experimental and simulated production conditions,a series of precipitated resultants were prepared by changing these variables one by one,and then examined by HPLC fingerprint analyses.Different from the traditional evaluation model based on single or a few constituents,the fingerprint data of every parameter fluctuation test was processed with Principal Component Analysis(PCA)to comprehensively assess the performance of ethanol precipitation.Our results showed that concentrate density,ethanol content,and precipitation time were the most important parameters that influence the recovery of active compounds in precipitation resultants.The present study would provide some reference for pharmaceutical scientists engaged in research on pharmaceutical process optimization and help pharmaceutical enterprises adapt a scientific and reasonable cost-effective approach to ensure the batch-to-batch quality consistency of the final products.

关键词： Traditional Chinese Medicines Ethanol precipitation Re Du Ning Injections Process parameter Principal Component Analysis

Evaluation of earthquake impact on magnitude of the minimum Principal stress along a shotcrete lined pressure tunnel in Nepal

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 920-934页

作者： Krishna Kanta Panthi Chhatra Bahadur Basnet Department of Ceoscience and Petroleum Norwegian University of Science and Technology

In situ stress condition in rock mass is influenced by both tectonic activity and geological environment such as faulting and shearing in the rock mass.This influence is of significance in the Himalayan region,where the tectonic movement is active,resulting in periodic dynamic earthquakes.Each large-scale earthquake causes both accumulation and sudden release of strain energy,instigating changes in the in situ stress environment in the rock mass.This paper first highlights the importance of the magnitude of the minimum Principal stress in the design of unlined or shotcrete lined pressure tunnel as water conveyance system used for hydropower schemes.Then we evaluated the influence of local shear faults on the magnitude of the minimum Principal stress along the shotcrete lined high pressure tunnel of Upper Tamakoshi Hydroelectric Project(UTHP)in Nepal.A detailed assessment of the in situ stress state is carried out using both measured data and three-dimensional(3D)numerical analyses with FLAC3D.Finally,analysis is carried out on the possible changes in the magnitude of the minimum Principal stress in the rock mass caused by seismic movement(dynamic loading).A permanent change in the stress state at and nearby the area of shear zones along the tunnel alignment is found to be an eminent process.

关键词： Shotcrete lined pressure tunnel The minimum Principal stress Three-dimensional(3D)numerical model Geology Tectonic activity Himalaya

Research on performance of complex networks based on Principal component analysis

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The Journal of China Universities of Posts and Telecommunications 2019年第1期26卷 40-48页

作者： Xu Chunxia Qi Xiaogang Liu Lifang School of Mathematics and Statistics Xidian University School of Computer Science and Technology Xidian University

For complex networks, their effectiveness and invulnerability are extremely important. With the development of complex networks, how to evaluate the effectiveness and invulnerability of these networks becomes an important research topic. The relationship among many influencing factors is very complicated, so it is essential to confirm the weighting coefficient of these influencing factors. Principal component analysis(PCA) is proposed to evaluate the performance of complex networks. It can improve one-sidedness of the single evaluation index and select different evaluation models according to different complex networks, which make the evaluation result more accurate. Performance of complex networks can be predicted according to comprehensive evaluation model. To verify the rationality and validity of this method, several small-world networks with different probability values and scale-free network are chosen to evaluate the network performance. Finally, simulation results show that PCA can be applied to performance evaluation of complex networks.

关键词： complex networks network topology Principal component analysis performance prediction

Compressive Sensing Sparse Sampling Method for Composite Material Based on Principal Component Analysis

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第2期35卷 282-289页

作者： Sun Yajie Gu Feihong Ji Sai Wang Lihua Jiangsu Engineering Centre of Network Monitoring Nanjing University of Information Science and Technology Nanjing 210044 P. R. China Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology Nanjing University of Information Science and Technology Nanjing 210044 P. R. China School of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044 P. R. China School of Information and Control Nanjing University of Information Science and Technology Nanjing 210014 P. R. China

Signals can be sampled by compressive sensing theory with a much less rate than those by traditional Nyquist sampling theorem,and reconstructed with high probability,only when signals are sparse in the time domain or a transform domain.Most signals are not sparse in real world,but can be expressed in sparse form by some kind of sparse transformation.Commonly used sparse transformations will lose some information,because their transform bases are generally fixed.In this paper,we use Principal component analysis for data reduction,and select new variable with low dimension and linearly correlated to the original variable,instead of the original variable with high dimension,thus the useful data of the original signals can be included in the sparse signals after dimensionality reduction with maximize portability.Therefore,the loss of data can be reduced as much as possible,and the efficiency of signal reconstruction can be improved.Finally,the composite material plate is used for the experimental verification.The experimental result shows that the sparse representation of signals based on Principal component analysis can reduce signal distortion and improve signal reconstruction efficiency.

关键词： Principal component analysis compressive sensing sparse representation signal reconstruction

Extrapolation Method for Cauchy Principal Value Integral with Classical Rectangle Rule on Interval

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Computer Modeling in Engineering & Sciences 2018年第6期115卷 313-326页

作者： Maohui Xia Jin Li School of Sciences Yanshan UniversityQinhuang Dao 066004China School of Sciences Shandong Jianzhu UniversityJinan 250101China

In this paper,the classical composite middle rectangle rule for the computation of Cauchy Principal value integral(the singular kernel 1=(x-s))is discussed.With the density function approximated only while the singular kernel is calculated analysis,then the error functional of asymptotic expansion is obtained.We construct a series to approach the singular point.An extrapolation algorithm is presented and the convergence rate of extrapolation algorithm is proved.At last,some numerical results are presented to confirm the theoretical results and show the efficiency of the algorithms.

关键词： Cauchy Principal value integral Extrapolation method Composite rectangle rule Superconvergence Error expansion

主成分分析结合Fisher最优分割法在烟叶分切中的应用

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烟草科技 2016年第8期49卷 83-88页

作者：龙明海资文华华一崑王跃昆林楠汪显国昆明理工大学化学工程学院云南瑞升烟草技术(集团)有限公司红云红河烟草(集团)有限责任公司

为探索烟叶原料分段打叶复烤较科学、合理的烟叶分切方法,以红大C3F等级初烤烟叶为研究对象,采用黄金分割法将烟叶进行分切并采集各段近红外光谱,运用主成分分析提取各段近红外光谱主成分,结合Fisher最优分割法对烟叶分切方法进行了研究... 详细信息

为探索烟叶原料分段打叶复烤较科学、合理的烟叶分切方法,以红大C3F等级初烤烟叶为研究对象,采用黄金分割法将烟叶进行分切并采集各段近红外光谱,运用主成分分析提取各段近红外光谱主成分,结合Fisher最优分割法对烟叶分切方法进行了研究,并从内在化学成分和感官质量两方面与现有分切方法的分段效果进行了对比评价。结果表明:1采用黄金分割法能将红大C3F等级初烤烟叶分切成11段,通过对各段近红外光谱进行主成分分析,最终确定了两个主成分用于反映原料信息,其累积方差贡献率达99.789%。2以主成分综合得分为基础,结合Fisher最优分割法确定了红大C3F等级初烤烟叶在实际生产中的最佳分段比例为叶基∶叶中∶叶尖=33%∶29%∶38%。3采用Fisher最优分割法分切后烟叶总糖、还原糖和烟碱等指标含量在叶基、叶中、叶尖之间的差异达到显著或极显著水平,叶基(44.87)、叶中(47.70)、叶尖(49.06)感官质量得分差距较大,且叶尖和叶中的感官质量得分相比现有分切方法均有不同程度提升,这为烟叶分段后科学打叶复烤加工与合理利用提供了参考。

关键词：烟叶黄金分割法主成分分析 Fisher最优分割法 Principal component analysis (PCA)