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Intelligent geochemical interpretation of mass chromatograms:Based on convolution neural network

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Petroleum Science 2024年第2期21卷 752-764页

作者： Kai-Ming su Jun-Gang lu Jian Yu Zi-Xing lu Shi-Jia Chen Hubei Key Laboratory of Petroleum Geochemistry and Environment Wuhan430100HubeiChina College of Resources and Environment Yangtze UniversityWuhan430100HubeiChina School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500SichuanChina Changqing Oilfield Company PetroChinaXi'an710021ShaanxiChina

Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic *** is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity ***,the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive,which increases the research cost and restrains extensive applications of this *** overcome this limitation,a correlation model is developed based on the convolution neural network(CNN)to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation,Ordos Basin,*** this way,the mass chromatogram can be automatically *** research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes(*** and PMI)that represent the organic matter thermal maturity and parent material type,***,training,interpretation,and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting,with the mass chromatogram used as the input and the obtained MI and PMI values for supervision(label).The optimized model presents high accuracy in automatically interpreting the mass chromatogram,with R2.alues typically above 0.85 and0.80 for the thermal maturity and parent material interpretation results,*** significance of this research is twofold:(i)developing an efficient technique for geochemical research;(ii)more importantly,demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies.

关键词： Organic geochemistry Biomarker Mass chromatographic analysis Automated interpretation Convolution neural network Machine learning

Theoretical prediction of ground settlements due to shield tunneling in multi-layered soils considering process parameters

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Underground Space 2024年第3期16卷 29-43页

作者： Liqiang Cao Xiangsheng Chen Dechun lu Dingli Zhang Dong su Institute of Geotechnical and Underground Engineering Beijing University of TechnologyBeijing 100124China Underground Polis Academy Shenzhen UniversityShenzhen 518060China Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China Key Laboratory for Resilient Infrastructures of Coastal Cities(MOE) Shenzhen UniversityShenzhen 518060China

This paper conducts a theoretical analysis of ground settlements due to shield tunneling in multi-layered soils which are usually encountered in urban *** proposed theoretical solution which is based on the general form of the Mindlin’s solution and Loganathan-Poulos formula can comprehensively consider the in-process tunneling parameters including:unbalanced face pressure,shield-soil friction,unbalanced tail grouting pressure,unbalanced secondary grouting pressure,overloading during tunneling and the ground volume *** method is verified by comparing with the field data from the Qinghuayuan Tunnel Project in terms of the ground surface settlements along the longitudinal and transverse *** to the local settlement or heave caused by the certain tunneling parameters,the ground surface settlements calculated using current solution along the longitudinal direction presents an irregular S-shaped curve instead of the traditional S-shaped *** also find that the effect of the unbalanced secondary grouting pressure and the overloading during tunneling cannot be ignored.

关键词： Tunneling Shield Ground settlements Theoretical analysis Urban areas Multi-layered soils Qinghuayuan Tunnel

Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China

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Chinese Geographical Science 2024年第1期34卷 135-148页

作者： WANG Zili lu Chunyan su Yanlin su Yue YU Qianru LI Wenzhe YANG Nuocheng College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou350002China Key Laboratory of Smart Agriculture and Forestry(Fujian Agriculture and Forestry University) Fujian Province UniversityFuzhou350002China College of Forestry Fujian Agriculture and Forestry UniversityFuzhou350002China

Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly *** order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving *** the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2.01 to *** comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically *** results showed that the winter LST presented an increasing trend in the study area during 2.01–2.2.,and the winter LST of the central urban regions was significantly higher than the *** was a strong UHI effect from 2.01 to 2.2.with an expansion trend from the central urban regions to the suburbs and coastal areas in space *** LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated *** and water bodies had a significant mitigation effect on UHI,especially in the *** winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading *** research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.

关键词： winter urban heat island(UHI) rapid urbanization area land surface temperature(LST)retrieval profile analysis GeoDetector model Fuzhou City,China

Morphological and sulfur-Isotopic Characteristics of Pyrites in the Deep Sediments from Xisha Trough,South China Sea

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Journal of Ocean University of China 2024年第1期23卷 138-148页

作者： CHANG Jingyi LIU Yujia lu Hailong lu Jing’an su Xin YE Jianliang XIE Wenwei College of Engineering Peking UniversityBeijing 100871China Beijing International Center for Gas Hydrate School of Earth and Planetary SciencesPeking UniversityBeijing 100871China School of Marine Science Nanjing University of Information Science and TechnologyNanjing 210044China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyMinistry of Land and ResourcesGuangzhou 510075China School of Ocean Sciences China University of GeosciencesBeijing 100083China

Pyrite is one of the common authigenic minerals in marine *** studies have shown that the morphological and isotopic characteristics of pyrite are closely related to the geochemical environment where it is *** better understand the for-mation mechanism of authigenic pyrite,we analyzed the isotopic composition,morphology,and distribution of pyrite in the sediment at 500m below the seafloor from Xisha Trough,South China *** morphologies were observed by scanning electron micros-copy and Raman spectrography.X-Ray computed tomography was applied to measure the particle size of *** size of pyrite crystals in the matrix sediment mainly ranged between 2. and 65µm(***.40µm),although crystals were larger(***.50μm)in the *** pyrites had a fine-grained truncated octahedral shape with occasionally well-developed growth steps,which implies the low growth rate and weak anaerobic oxidation of methane-sulfate reduction when pyrite was ***δ^(34)S values of pyrites ranged from+2..8‰Vienna-defined Canyon Diablo Troilite(V-CDT)to+33.2.V-CDT and from+44.8‰V-CDT to+48.9‰,which suggest two growth *** the first stage,with the continuous low methane flux,the pyrite possibly formed in an environment with good access to *** the second stage,the pyrites mainly developed in sediment fractures and appeared in veins,probably due to the limited availability of *** less exposure of pyrite to the environment in the second stage was probably caused by sediment accumulation or *** this study,an episodic pyritization process was identified,and the paleoenvironment was reconstructed for the sediment investigated.

关键词： pyrite sulfur isotope AOM methane flux Xisha Trough South China Sea

Association of complement components with risk of colorectal cancer:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2168-2180页

作者： Xiao-Lin Zhu lu Zhang su-Xia Qi Department of Gastroenterology Qingdao Municipal HospitalQingdao 266071Shandong ProvinceChina Department of Medical Administration Qingdao Municipal HospitalQingdao 266071Shandong ProvinceChina

BACKGROUND Complement components could contribute to the tumor microenvironment and the systemic immune ***,their role in colorectal cancer(CRC)remains a contentious *** To elucidate the relationship between complement components and CRC risk and clinical *** Searches were conducted in PubMed,the Cochrane Library,and the China National Knowledge Infrastructure database until June 1,*** included cohort studies encompassing participants aged≥18 years,investigating the association between complement components and *** studies were of moderate quality or above,as determined by the Agency for Healthcare Research and *** meta-analysis employed fixed-effects or random-effects models based on the I^(2.test,utilizing risk ratio(RR)and their corresponding 95%confidence interval(CI)for *** and subgroup analyses were performed to validate the robustness of the collective estimates and identify the source of *** Data from 15 studies,comprising 1631 participants that met the inclusion criteria,were included in the *** findings indicated that protein levels of cluster of differentiation 46(CD46)(RR=3.66,95%CI:1.75-7.64,P2.86,95%CI:1.36-6.01,P=0.005),and component 1(C1)(RR=5.88,95%CI:1.75-19.73,P=0.004)and serum levels of C3(standardized mean difference=1.82.95%CI:0.06-3.58,P=0.040)were significantly elevated in patients with CRC compared to healthy *** expression of CD55 or CD59 was associated with a higher incidence of lymph node metastasis,whereas strong CD46 expression correlated with a higher incidence of tumor differentiation compared to low CD46 expression(Psults demonstrated notable heterogeneity,subgroup analyses pointed to regional differences as the primary source of inconsistency among the *** Our analysis underscores that increased levels of specific complement components are

关键词： Complement components Colorectal cancer Lymph node metastasis Systematic review Meta-analysis

Generative deep-learning-embedded asynchronous structured light for three-dimensional imaging

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Advanced Photonics 2024年第4期6卷 45-58页

作者： Lei lu Chenhao Bu Zhilong su Banglei Guan Qifeng Yu Wei Pan Qinghui Zhang Henan University of Technology College of Information Science and EngineeringZhengzhouChina Shanghai University Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai Key Laboratory of Mechanics in Energy EngineeringShanghaiChina Shaoxing Research Institute of Shanghai University ShaoxingChina National University of Defense Technology College of Aerospace Science and EngineeringChangshaChina OPT Machine Vision Tech Co. Ltd.Department of Research and DevelopmentDongguanChina

Three-dimensional(3D)imaging with structured light is crucial in diverse scenarios,ranging from intelligent manufacturing and medicine to ***,current structured light methods rely on projector-camera synchronization,limiting the use of affordable imaging devices and their consumer *** this work,we introduce an asynchronous structured light imaging approach based on generative deep neural networks to relax the synchronization constraint,accomplishing the challenges of fringe pattern aliasing,without relying on any a priori constraint of the projection *** overcome this need,we propose a generative deep neural network with U-Net-like encoder-decoder architecture to learn the underlying fringe features directly by exploring the intrinsic prior principles in the fringe pattern *** train within an adversarial learning framework and supervise the network training via a statisticsinformed loss *** demonstrate that by evaluating the performance on fields of intensity,phase,and 3D *** is shown that the trained network can separate aliased fringe patterns for producing comparable results with the synchronous one:the absolute error is no greater than 8μm,and the standard deviation does not exceed 3μ*** results on multiple objects and pattern types show it could be generalized for any asynchronous structured light scene.

关键词： structured light fringe pattern projection asynchrony deep learning generative neural networks three-dimensional imaging

A Novel Recovery Strategy to suppress subsequent Commutation Failure in an LCC-Based HVDC

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Protection and Control of Modern Power Systems 2024年第1期9卷 38-51页

作者： Changsheng su Chunya Yin Fengting Li lu Han 不详 School of Electrical Engineering Xinjiang UniversityUrumqi 830017China

A subsequent commutation failure(SCF)can easily occur during the recovery process after a first commutation failure(1st CF).This paper analyzes the interaction mechanism of extinction angle,AC voltage,DC current and firing angle,and reveals that the complex coupling relationship during the dynamic process after the 1st CF has a significant effect on the *** mathematical equations when considering different fault durations,fault severities and AC system strengths are then *** AC fault voltage detection method based on reactive power and fault duration is also proposed to measure the fault severity,and an SCF inhibition control strategy(SCFICS)based on AC fault detection and reactive power control is subsequently *** can not only inhibit the SCF,but also enhance the DC recovery speed ***,based on the SCFICS,a simulation model is built,and the simulation results with different cases indicate that the SCFICS can effectively inhibit the SCF with good recovery performance,for three-phase-to-ground(TPG)and single-phase-to-ground faults,and with a fault inductance range of 0.01 H to 1 H.

关键词： fault extinction angle

Exploring plant adaptation strategies to phosphorus limitation induced by nitrogen addition:foliar phosphorus allocation and root functional traits analysis in two dominant subalpine tree species

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Journal of Plant Ecology 2024年第4期17卷 154-166页

作者： Yan su Yongfeng Tang Yi Hu Meiyu Liu Xuyang lu Baoli Duan Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Sichuan Ecological Environment Construction Engineering supervision Co. Ltd.Chengdu 610084China

Plants adapt to the limitation of soil phosphorus(P)induced by nitrogen(N)deposition through a complex interaction of various root and leaf functional *** this study,a pot experiment was conducted to explore the effects of different levels of N addition(control,low N[LN]:2. kg N ha^(-1) yr^(-1),high N[HN]:50 kg N ha^(-1) yr^(-1))on tree growth,leaf nutrient content,foliar P fractions and root characteristics of two dominant tree species,the pioneer species Salix rehderiana Schneid and the climax species Abies fabri(Mast.)Craib,in a subalpine forest in southwestern *** results demonstrated that LN addition had a minimal impact on leaf N and P ***,HN addition significantly decreased the leaf P content in both *** rehderiana exhibited more pronounced increases in specific root length and specific root area under P deficiency triggered by HN addition when compared with *** contrast,*** showed weaker morphological responses to N addition but had a higher proportion of foliar P to metabolic P,as well as higher root exudates rate and root phosphatase activity in response to HN *** fabri employs a synergistic approach by allocating a greater amount of leaf P to metabolite P and extracting P from the soil through P-mobilizing exudates and root phosphatase activity,while *** exhibits higher flexibility in modifying its root morphology in response to P limitation induced by HN *** study provides insights into subalpine tree species adaptation to N-induced P limitation,emphasizing its significance for guiding forest management and conservation in the context of global climate change.

关键词： N deposition root functional traits root morphology root exudation P-scavenging strategy

Recognition of Organizational Morphology of Mesoscale Convective Systems Using Himawari-8 Observations

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Journal of Tropical Meteorology 2024年第3期30卷 289-305页

作者： SHOU Yi-xuan ZHANG su-zhao lu Feng Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological Center(National Center for Space Weather)China Meteorological AdministrationBeijing 100081 China Innovation Center for FengYun Meteorological Satellite(FYSIC) Beijing 100081 China Key Laboratory for Meteorological Disaster Monitoring and Early Warning and Risk Management of Characteristic Agriculture in Arid Regions Yinchuan 750002 China Ningxia Key Laboratory of Meteorological Disaster Prevention and Mitigation Yinchuan 750002 China

The onset,evolution,and propagation processes of convective cells can be reflected by the organizational morphology of mesoscale convective systems(MCSs),which are key factors in determining the potential for heavy *** paper proposed a method for objectively classifying and segmenting MCSs using geosynchronous satellite *** of the product relative to the classification in radar composite reflectivity imagery indicates that the algorithm offers skill for discriminating between convective and stratiform areas and matched 65%of convective area identifications in radar imagery with a false alarm rate of 39%and an accuracy of 94%.A quantitative evaluation of the similarity between the structures of 50 MCSs randomly obtained from satellite and radar observations shows that the similarity was as high as 60%.For further testing,the organizational modes of the MCS that caused the heavy precipitation in Northwest China on August 2.,2.16(hereinafter known as the“082.”rainstorm)were *** was found that the MCS,accompanied by the“082.”rainstorm,successively exhibited modes of the isolated cell,squall line with parallel stratiform(PS)rain,and non-linear system during its life *** them,the PS mode might have played a key role in causing this *** findings are in line with previous studies.

关键词： mesoscale convective system satellite organizational morphology extremely heavy precipitation