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Auto machine learning-based modelling and prediction of excavationinduced tunnel displacement

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1100-1114页

作者： Dongmei Zhang Yiming Shen Zhongkai Huang xiaochuang Xie Key Laboratory of Geotechnical and Underground Engineering Ministry of EducationTongji UniversityShanghai200092China Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China

The influence of a deep excavation on existing shield tunnels nearby is a vital issue in tunnelling engineering.Whereas,there lacks robust methods to predict excavation-induced tunnel displacements.In this study,an auto machine learning(AutoML)-based approach is proposed to precisely solve the issue.Seven input parameters are considered in the database covering two physical aspects,namely soil property,and spatial characteristics of the deep excavation.The 10-fold cross-validation method is employed to overcome the scarcity of data,and promote model’s robustness.Six genetic algorithm(GA)-ML models are established as well for comparison.The results indicated that the proposed AutoML model is a comprehensive model that integrates efficiency and robustness.Importance analysis reveals that the ratio of the average shear strength to the vertical effective stress E_(ur)/σ′_(v),the excavation depth H,and the excavation width B are the most influential variables for the displacements.Finally,the AutoML model is further validated by practical engineering.The prediction results are in a good agreement with monitoring data,signifying that our model can be applied in real projects.

关键词： Soilestructure interaction Auto machine learning(AutoML) Displacement prediction Robust model Geotechnical engineering

An optimized hexagonal quadtree encoding and operation scheme for icosahedral hexagonal discrete global grid systems

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International Journal of Digital Earth 2022年第1期15卷 975-1000页

作者： Long Zhao Guoqing Li xiaochuang Yao Yue Ma Qianqian Cao Aerospace Information Research Institute Chinese Academy of SciencesBeijingPeople’s Republic of China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijingPeople’s Republic of China College of Land Science and Technology China Agricultural UniversityBeijingPeople’s Republic of China

Although research on the discrete global grid systems (DGGSs) has become an essential issue in the era of big earth data,there is still a gap between the efficiency of current encoding and operation schemes for hexagonal DGGSs and the needs of practical applications. This paper proposes a novel and efficient encoding and operation scheme of an optimized hexagonal quadtree structure (OHQS) based on aperture 4 hexagonal discrete global grid systems by translation transformation. A vector model is established to describe and calculate the aperture 4 hexagonal grid system. This paper also provides two different grid code addition algorithms based on induction and ijk coordinate transformation. We implement the transformation between OHQS codes and geographic coordinates through the ij,ijk and IJK coordinate systems. Compared with existing schemes,the scheme in this paper greatly improves the efficiency of the addition operation,neighborhood retrieval and coordinate transformation,and the coding is more concise than other aperture 4 hexagonal DGGSs. The encoding operation based on the ijk coordinate system is faster than the encoding operation based on the induction and addition table. Spatial modeling based OHQS DGGSs are also provided. A case study with rainstorms demonstrated the availability of this scheme.

关键词： Discrete global grid systems hexagon quadtree encoding

Heterostructure design of MOFs derived Co_(9)S_(8)/FeCoS_(2)/C composite with efficient microwave absorption and waterproof functions

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Journal of Materials Science & Technology 2022年第34期129卷 15-26页

作者： Runrun cheng Yan Wang xiaochuang Di Zhao Lu Ping Wang Xinming Wu School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China

At present, the problem of electromagnetic wave(EMW) pollution is critical, and the design of highperformance absorbers is of great significance. Based on the synergy between dielectric and magnetic losses, and between multicomponents in heterostructures, the development of light-weight absorbers with a strong absorption capability and multiple scattering is a promising strategy to achieve highperformance absorbers. In this work, CoFe-MOF precursors with a bouquet-like structure were prepared via the hydrothermal method, and Co_(7)Fe_(3)/C and Co_(9)S_(8)/FeCoS_(2)/C composites were obtained through a carbonization and sulfuration treatment during the high-temperature pyrolysis process, respectively. The experimental and theoretical results show that the Co_(9)S_(8)/FeCoS_(2)/C composite has a better EMW absorption performance, and its optimal reflection loss(RL) value is-53.9 d B at a low filler loading of 20 wt.%,which is due to the S doping that enhances the interface polarization relaxation process and improves the impedance matching characteristics. Moreover, the Co_(9)S_(8)/FeCoS_(2)/C composite can be as candidates of high-efficiency absorbers in extreme application environments.

关键词： Electromagnetic absorption Metal-organic frameworks(MOFs) Bouquet-like CoFe-MOF Sulfur doping

Rapid identification of chemical profile in Gandou decoction by UPLCQ-TOF-MSE coupled with novel informatics UNIFI platform

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Journal of Pharmaceutical Analysis 2020年第1期10卷 35-48页

作者： Li Xu Yi Liu Hongfei Wu Huan Wu xiaochuang Liu An Zhou The Experimental Research Center Anhui University of Chinese MedicineHefei 230038China Anhui Province Key Laboratory of Chinese Medicinal Formula Hefei 230012China Waters Corporation(China) Shanghai 201206China

Gandou decoction(GDD),a well-known traditional Chinese medicine(TCM)formula,has been widely used for decades to treat Wilson's disease(WD)in China due to its remarkable clinical effects.However,the chemical constituents of GDD still remain unclear because of their complexity.In this work,a reliable and sensitive strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MSE)and UNIFI informatics platform was applied to investigate the chemical components in GDD.In total,96 compounds including anthraquinones,alkaloids,protostane triterpenoids,flavonoids,triterpenoid saponins,tannins,curcuminoids,etc,were identified or tentatively characterized from GDD by comparing their retention time,accurate mass within 5 ppm error and MSE fragmentation patterns.Among them,eleven compounds were confirmed unambiguously with reference standards.Representative compounds in different chemical structure types were analyzed in fragmentation patterns and characteristic ions.Moreover,to better understand the chemical contribution of individual herbs to the whole decoction,the corresponding each herb in GDD was also detected.This study developed a rapid method for characterizing the chemical constituents in GDD,which could not only be used for chemical standardization and quality control,but also be helpful for further research of GDD in vivo.

关键词： Gandou decoction UPLC-Q-TOF-MSE UNIFI informatics platform Chemical constituents

A unified representation method for interdisciplinary spatial earth data

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Big Earth Data 2023年第1期7卷 126-145页

作者： Shuang Wang Jian Wang Qin Zhan Lianchong Zhang xiaochuang Yao Guoqing Li Aerospace Information Research Institute Chinese Academy of SciencesBeijingChina School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijingChina College of Land Science and Technology China Agricultural UniversityBeijingChina

Unified representation of spatial earth data is an essential scientific issue.The analysis and mining of interdisciplinary spatial earth data resources can help discover hidden scientific knowledge,and even reveal the intrinsic relationship among different disciplines.However,the different description methods and inner structures among interdisciplinary spatial earth data bring significant chal-lenges to unified data management and collaborative analysis in earth environment research.To address this issue,this paper pro-poses a unified representation method for interdisciplinary spatial earth data.First,this paper establishes a general metadata model and realizes the unified description of interdisciplinary data.Second,an entity data organization model is presented,which can realize the unified organization of entity data with different inner structures.Finally,we introduce the Spatial Earth Data Format(SEDF),a data format based on HDF5 for implementing the data organization model of interdisciplinary spatial earth data.Data representation experiments and validation are conducted to verify the availability and practicability of the proposed data representa-tion method.The results suggest the powerful ability to represent spatial earth data efficiently and ensure data integrity,which is convenient for data management and application.

关键词： Unified representation spatial earth data general metadata model data organization model Spatial Earth Data Format

改性剂和矿物掺合料对硫氧镁水泥耐水性的影响研究进展

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水利水电技术（中英文） 2023年第8期54卷 188-196页

作者：张晓闯陈波王雄锋马豪达南京水利科学研究院水文水资源与水利工程科学国家重点实验室江苏南京210029

【目的】硫氧镁(简称MOS)水泥是由硫酸镁(MgSO_(4))溶液和轻烧氧化镁(MgO)混合制得的镁质胶凝材料,具有轻质、耐高温、易制备、绿色环保等特点,但是MOS水泥耐水性差的特性限制了其工程应用场景。为梳理MOS水泥耐水性的改善措施和改性后... 详细信息

【目的】硫氧镁(简称MOS)水泥是由硫酸镁(MgSO_(4))溶液和轻烧氧化镁(MgO)混合制得的镁质胶凝材料,具有轻质、耐高温、易制备、绿色环保等特点,但是MOS水泥耐水性差的特性限制了其工程应用场景。为梳理MOS水泥耐水性的改善措施和改性后的效果,【方法】根据国内外学者的研究成果,概述了柠檬酸(CA)、水玻璃(SS)、磷酸(PA)、酒石酸(TA)等改性剂和粉煤灰(FA)、硅灰(FS)、矿渣等掺合料对MOS水泥耐水性的作用效果,总结了改性剂和矿物掺合料对MOS水泥软化系数、微观结构和物相组成的影响,分析了改性剂和掺合料的改善机理。【结果】发现改性后MOS水泥软化系数能够保持在0.8以上,有害孔减少,总孔隙率降低,结构更加密实,有更多5·1·7相生成。【结论】适宜的改性剂和适当的掺合料会显著提升硫氧镁水泥的耐水性能。最后,对MOS水泥目前存在的问题和未来发展进行分析与展望,为继续研究MOS水泥耐水性提供思路。

关键词：硫氧镁(MOS)水泥改性剂耐水性掺合料软化系数 5·1·7相

Big spatial vector data management: a review

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Big Earth Data 2018年第1期2卷 108-129页

作者： xiaochuang Yao Guoqing Li Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijingChina

Spatial vector data with high-precision and wide-coverage has exploded globally,such as land cover,social media,and other data-sets,which provides a good opportunity to enhance the national macroscopic decision-making,social supervision,public services,and emergency capabilities.Simultaneously,it also brings great challenges in management technology for big spatial vector data(BSVD).In recent years,a large number of new concepts,parallel algorithms,processing tools,platforms,and applications have been proposed and developed to improve the value of BSVD from both academia and industry.To better understand BSVD and take advantage of its value effectively,this paper presents a review that surveys recent studies and research work in the data management field for BSVD.In this paper,we discuss and itemize this topic from three aspects according to different information technical levels of big spatial vector data management.It aims to help interested readers to learn about the latest research advances and choose the most suitable big data technologies and approaches depending on their system architectures.To support them more fully,firstly,we identify new concepts and ideas from numerous scholars about geographic information system to focus on BSVD scope in the big data era.Then,we conclude systematically not only the most recent published literatures but also a global view of main spatial technologies of BSVD,including data storage and organization,spatial index,processing methods,and spatial analysis.Finally,based on the above commentary and related work,several opportunities and challenges are listed as the future research interests and directions for reference.

关键词： Big data vector data big spatial vector data(BSVD) big data management review

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China Oil & Gas 2017年第2期24卷 63-64,135-136页

作者： Yi xiaochuang

Public relation staff of the Ahdeb Project of the Middle East Company: Their work varies in magnitude; it can be as broad as establishing friendships and coordinating cooperation with the locals, or it can be as detail-oriented as communicating with the local people for the construction and maintenance of a relationship between the oil field and the local community.

关键词： villagerswork oilfield

基于ANSYS的26t桁架门式起重机有限元分析

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现代机械 2016年第4期 55-57页

作者：王晓闯陈雁涛铁道第三勘察设计院集团有限公司天津300142

为了验证现代设计计算方法的正确性和高效性,本文在确定桁架门式起重机参数的情况下,利用有限元软件ANSYS建模分析,校核主梁的强度、刚度、稳定性等参数,证明满足设计要求;同时通过有限元模态分析,通过提取模态来确定起重机的固有频率,... 详细信息

为了验证现代设计计算方法的正确性和高效性,本文在确定桁架门式起重机参数的情况下,利用有限元软件ANSYS建模分析,校核主梁的强度、刚度、稳定性等参数,证明满足设计要求;同时通过有限元模态分析,通过提取模态来确定起重机的固有频率,证明振动频率满足设计要求。

关键词：桁架门式起重机 ANSYS 强度刚度