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Real-time prediction of mechanical behaviors of underwater shield tunnel structure using machine learning method based on structural health monitoring data

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 886-895页

作者： Xuyan Tan Weizhong Chen Tao Zou Jianping Yang Bowen Du State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China State Key Laboratory of Software Development Environment Beihang UniversityBeijing100191China

Predicting the mechanical behaviors of structure and perceiving the anomalies in advance are essential to ensuring the safe operation of infrastructures in the long *** addition to the incomplete consideration of influencing factors,the prediction time scale of existing studies is ***,this study focuses on the development of a real-time prediction model by coupling the spatio-temporal correlation with external load through autoencoder network(ATENet)based on structural health monitoring(SHM)*** autoencoder mechanism is performed to acquire the high-level representation of raw monitoring data at different spatial positions,and the recurrent neural network is applied to understanding the temporal correlation from the time ***,the obtained temporal-spatial information is coupled with dynamic loads through a fully connected layer to predict structural performance in next 12 *** a case study,the proposed model is formulated on the SHM data collected from a representative underwater shield *** robustness study is carried out to verify the reliability and the prediction capability of the proposed ***,the ATENet model is compared with some typical models,and the results indicate that it has the best *** model is of great value to predict the realtime evolution trend of tunnel structure.

关键词： Shied tunnel Machine learning Monitoring Real-time prediction data analysis

Wiener Filtration Algorithm of an Ensemble Pulsar Timescale Based on a Power-law Model of Pulsar Power Spectrum

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Research in Astronomy and Astrophysics 2022年第10期22卷 129-140页

作者： Ting-Gao Yang Ming-Lei Tong Yu-Ping Gao National Time Service Center Chinese Academy of SciencesXi'an 710600China Key Laboratory of Time and Frequency Primary Standards Chinese Academy of SciencesXi'an 71000China University of Chinese Academy of Sciences Beijing 100049China

An ensemble pulsar timescale derived from the traditional Wiener filtration still contains some high level *** improve this situation we developed a Wiener filtration algorithm of the ensemble pulsar timescale based on a power-law model of power spectrum for *** algorithm has three strengths:(1)mitigating spectral leakage between frequency bins for Fourier techniques;(2)using a power-law model for power spectrum;(3)signal realization in original residuals of data set by the power-law *** to improved algorithm we constructed an ensemble pulsar timescale EPT-TAI using timing data with respect to International Atomic Time(TAI)about 16 yr time span of ten pulsars from International Pulsar Timing Array second data release(version A).The results show that EPT-TAI detected correctly the differences TT(BIPM2015)-TAI between terrestrial time TT(BIPM2015)and *** frequency stabilityσzanalysis shows that EPT-TAI does not indicate red noise for 16 yr time interval,and fractional frequency stability for 8 yr and longer time intervals is slightly better than that of TT(BIPM2015)-*** for short time intervals of TT(BIPM2015)-TAI is better than that of EPT-TAI,but TT(BIPM2015)-TAI shows red noise for longer time *** the same algorithm we also derived an ensemble pulsar timescale EPT-TT(BIPM2015)with respect to TT(BIPM2015).The fractional frequency stability curve of EPT-TT(BIPM2015)shows similar characteristics as that of EPT-TAI but with slightly lower values.

关键词： (stars:)pulsars general-time-methods data analysis

An algorithm to resolve γ-rays from charged cosmic rays with DAMPE

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Research in Astronomy and Astrophysics 2018年第3期18卷 25-36页

作者： Zun-Lei Xu Kai-Kai Duan Zhao-Qiang Shen Shi-Jun Lei Tie-Kuang Dong Fabio Gargano Simone Garrappa Dong-Ya Guo Wei Jiang Xiang Li Yun-Feng Liang Mario Nicola Mazziotta Maria Fernanda Munoz Salinas Meng Su Valerio Vagelli Qiang Yuan Chuan Yue Jing-Jing Zang Ya-Peng Zhang Yun-Long Zhang Stephan Zimmer Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China University of Chinese Academy of Sciences Beijing 100049 China Istituto Nazionale di Fisica Nucleare Sezione di Bari I-70125 Bari Italy Istituto Nazionale di Fisica Nucleare Sezione di Perugia I-06123 Perugia Italy Dipartimento di Fisica e Geologia Universita degli Studi di Perugia I-06123 Perugia Italy Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Nuclear and Particle Physics University of Geneva CH- 1211 Switzerland School of Astronomy and Space Science University of Science and Technology of China Hefei 230026 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of China Hefei 230026 China

The DArk Matter Particle Explorer（DAMPE）,also known as Wukong in China,which was launched on 2015 December 17,is a new high energy cosmic ray and γ-ray satellite-borne *** of the main scientific goals of DAMPE is to observe Ge V-Te V high energy γ-rays with accurate energy,angular and time resolution,to indirectly search for dark matter particles and for the study of high energy astrophysics. Due to the comparatively higher fluxes of charged cosmic rays with respect to γ-rays,it is challenging to identify γ-rays with sufficiently high efficiency,minimizing the amount of charged cosmic ray contamination. In this work we present a method to identify γ-rays in DAMPE data based on Monte Carlo simulations,using the powerful electromagnetic/hadronic shower discrimination provided by the calorimeter and the veto detection of charged particles provided by the plastic scintillation detector. Monte Carlo simulations show that after this selection the number of electrons and protons that contaminate the selected γ-ray events at～10 Ge V amounts to less than 1% of the selected ***,we use flight data to verify the effectiveness of the method by highlighting known γ-ray sources in the sky and by reconstructing preliminary light curves of the Geminga pulsar.

关键词： gamma rays general - instrumentation detectors - methods data analysis

A study of short-period variation in solar activity

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Research in Astronomy and Astrophysics 2014年第8期14卷 1011-1018页

作者： Ji-Long Chen Juan Zhao Department of Astronomy Beijing Normal University

We introduce two methods to detect short-period variation in solar activity. These are called amplitude of low frequency fluctuation （ALFF） and fractional am- plitude of low frequency fluctuation （FALFF）. We find a positive correlation between short-period variation and 11-year variation of solar activity using these two methods. Through ALFF, we find that solar activity over a short period becomes intensive when the 11-year solar activity is intensive. The ALFF value of the short period activity varies with the peak in sunspot number as a quadratic function. Through FALFF we find that the ratio of short-period spectral intensity to intensity over the whole period of solar activity will increase when the 11-year period of solar activity is intensive. The short-period FALFF value varies with the peak in sunspot number according to a cubic function. Using ALFF, we obtain a yearly series of solar activity that varies over a short period of 1-5 yr from 1860 to 2003, which shows an obvious periodicity of about 22 yr, 33 yr, 11 yr and a century. These short period variations show good correlations with long term variations in solar activity.

关键词： Sun activity -- Sun sunspots -- methods data analysis

An Ensemble Methods for Medical Insurance Costs Prediction Task

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Computers, Materials & Continua 2022年第2期70卷 3969-3984页

作者： Nataliya Shakhovska Nataliia Melnykova Valentyna Chopiyak Michal Gregus ml Department of Artificial Intelligence Lviv Polytechnic National UniversityLviv79013Ukraine Department of Clinical Immunology and Allergology Danylo Halytsky Lviv National Medical UniversityLviv79010Ukraine Faculty of Management Comenius UniversityBratislava81499Slovakia

The paper reports three new ensembles of supervised learning predictors for managing medical insurance *** open dataset is used for data analysis methods *** usage of artificial intelligence in the management of financial risks will facilitate economic wear time and money and protect patients’*** learning is associated withmany expectations,but its quality is determined by choosing a good algorithm and the proper steps to plan,develop,and implement the *** paper aims to develop three new ensembles for individual insurance costs prediction to provide high prediction *** coefficient and Boruta algorithm are used for feature *** boosting,stacking,and bagging ensembles are built.A comparison with existing machine learning algorithms is *** modes based on regression tree and stochastic gradient descent is *** CART and Random Forest algorithms are *** boosting and stacking ensembles shown better accuracy than *** tuning parameters for boosting do not allow to decrease the RMSE ***,bagging shows its weakness in generalizing the *** stacking is developed using K Nearest Neighbors(KNN),Support Vector Machine(SVM),Regression Tree,Linear Regression,Stochastic Gradient *** random forest(RF)algorithm is used to combine the *** hundred trees are built *** Square Error(RMSE)has lifted the to 3173.213 in comparison with other *** quality of the developed ensemble for RootMean Squared Error metric is 1.47 better than for the best weak predictor(SVR).

关键词： Healthcare medical insurance prediction task machine learning ensemble data analysis

Which Is Safer,Chinese Medicine or Western Medicine?Comparative analysis Based on Chinese Spontaneous Reporting database

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Chinese Journal of Integrative Medicine 2022年第2期28卷 138-144页

作者： WEI Jian-xiang LU Zhi-qiang FENG Guan-zhong ZHU Yun-xia School of Management Nanjing University of Posts and TelecommunicationsNanjing(210003)China School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing(210003)China

Objective:To compare the safety differences between Chinese medicine(CM)and Western medicine(WM)based on Chinese Spontaneous Reporting database(CSRD).Methods:Reports of adverse events(AEs)caused by CM and WM in the CSRD between 2010 and 2011 were *** following assessment indicators were constructed:the proportion of serious AEs(PSE),the average number of AEs(ANA),and the coverage rate of AEs(CRA).Further comparisons were also conducted,including the drugs with the most reported serious AEs,the AEs with the biggest report number,and the 5 serious AEs of interest(including death,anaphylactic shock,coma,dyspnea and abnormal liver function).Results:The PSE,ANA and CRA of WM were 1.09,8.23 and 2.35 times higher than those of CM,*** top 10 drugs with the most serious AEs were mainly injections for CM and antibiotics for *** AEs with the most reports were rash,pruritus,nausea,dizziness and vomiting for both CM and *** proportions of CM and WM in anaphylactic shock and coma were *** abnormal liver function and death,the proportions of WM were 5.47 and 3.00 times higher than those of CM,***:Based on CSRD,CM was safer than WM at the average level from the perspective of adverse drug reactions.

关键词： Chinese medicine Western medicine data analysis adverse drug reaction drug safety

Integrated geoscience databanks for interactive analysis and visualization

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International Journal of Digital Earth 2013年第S02期6卷 41-49页

作者： Khalid Amin Khan Gulraiz Akhter Zulfiqar Ahmad K-tron Research Inc. RawalpindiPakistan Department of Earth Sciences Quaid-i-Azam UniversityIslamabadPakistan

There has been a worldwide revolution in geoscientific data availability and *** effectively infinite and instantaneous free access to geoscientific data from the World Wide System of Geoscience data Centers and Virtual Observatories is *** addition,national databanks and commercially available large exploration data-sets also *** distributed data resources impose challenges for the future to move toward their objective integration and visualization to discover new *** advancements can facilitate meaningful interpretations and decision-making for the benefit of society at global and local *** article presents the Digital Earth initiative at a national level to address multiple domains,such as effective management of natural resources,interactive planning of exploration activities and monitoring,mapping and mitigation of natural *** discusses a distributed geospatial data infrastructure and its importance in geoscientific data integration for efficient and interactive data retrieval,analysis and *** examples are presented to demonstrate the advantages of integrated visualization in geoscientific analysis.

关键词： distributed data geospatial data integration spatial data infrastructure data analysis visualization digital country

Correction of the temperature effect in calibration of a solar radio telescope

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Research in Astronomy and Astrophysics 2021年第6期21卷 349-358页

作者： Li-Hong Geng Cheng-Ming Tan Yi-Hua Yan Bao-Lin Tan Dong-Hao Liu Jin-Ping Dun CAS key Laboratory of Solar Activity National Astronomical Observatories of Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijing 100081China

This work analyzes the annual fluctuation of the observation data of the Mingantu Solar radio Telescope(MST)in S,C and X *** is found that the data vary with local air temperature as the logarithmic attenuation of equipment increases with temperature and frequency.A simplified and effective calibration method is proposed,which is used to calibrate the MST data in 2018-2020,while the correction coefficients are calculated from data in *** S,C and X bands,the root mean square errors of one polarization are 2.7,5.7 and 20 sfu,and the relative errors are 4%,6%and 8%*** calibration of MUSER and SBRS spectra is also *** relative errors of MUSER at 1700 MHz,SBRS at 2800 MHz,3050 MHz and 3350 MHz are 8%,8%,11%and 10%*** found that several factors may affect the calibration accuracy,especially at *** method is expected to work for other radio telescopes with similar design.

关键词： instrumentation polarimeters methods data analysis methods:observational

Preliminary analysis of species sensitivity distribution based on gene expression effect

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Science China Earth Sciences 2012年第6期55卷 907-913页

作者： YAN ZhenGuang YANG NiYun WANG XiaoNan WANG WanHua MENG ShuangShuang LIU ZhengTao State Key Laboratory of Environmental Criteria and Risk Assessment State Environmental Protection Key Laboratory of Ecological Effect and Risk Assessment of Chemicals Chinese Research Academy of Environmental Sciences Beijing 100012 China

Species sensitivity analysis is one of the major techniques applied to derive water quality criteria. Presently, the toxicity data used for development of water quality criteria are mainly in the biological individual level. With the increase of ecotoxicogenomics toxicity data, it is worth studying whether the gene expression effect data can be used to derive water quality criteria. Taking cadmium, copper and zinc as examples, we analyzed the toxic effects of the three heavy metals by constructing the species sensitivity distribution curves on the basis of extensive toxicity data. The results showed that the rank of species sensitivity for the acute, chronic and gene expression effect toxicity data of cadmium is "chronic>gene>acute". Although the gene expression effect data of copper and zinc are insufficient, the trend of data sensitivity of zinc is similar to cadmium. However, the trend of species sensitivity of copper is different from that of cadmium and zinc with higher sensitivity of gene expression data. It suggested that though the existing data of gene expression effects are not sufficient enough, they have the potential to be used in the development of chronic water quality criteria. For application in the derivation of water quality criteria, illogical test concentration design and insufficient target genes are two main weaknesses in the study of gene expression effects.

关键词： water quality criteria heavy metal gene expression effect species sensitivity distribution data analysis