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Structural characteristics of cement-stabilized soil bases with 3D finite element method

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Frontiers of Structural and Civil Engineering 2009年第4期3卷 428-434页

作者： Yunfeng PENG yunlong he College of Civil and Hydropower Engineering China Three Gorges UniversityYichang 443002China College of Water Resources and Hydroelectric Engineering Wuhan UniversityWuhan 430072China

Cement-stabilized soil bases have been widely used in expressways due to its high strength,appropriate stiffness,good water resistance,and frost *** far,the structural characteristics and mechanical behaviors of cement-stabilized soil bases were not investigated so *** this paper,the 3D elastic-plastic finite element method(FEM)was used to analyze the mechanical behaviors and structural characteristics of cementstabilized soil bases from construction to *** pavement filling and the traffic loading processes were simulated,and a contact model was used to simulate the contact behavior between each layer of the *** the construction process,the structural characteristics and mechanical behaviors of cementstabilized soil bases were studied under asphalt-concrete pavement ***,the general rules of deformations and stresses in cement-stabilized soil bases under different conditions were discussed,and some suggestions were put forward for the design and construction of cement-stabilized soil bases.

关键词： cement-stabilized soil semi-rigid base elastic-plastic finite element method structure characteristic mechanical response

Depositional Characteristics and Formation Mechanisms of Deep-Water Canyon Systems along the Northern South China Sea Margin

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Journal of Earth Science 2020年第4期31卷 808-819页

作者： Hui Chen Xinong Xie Kainan Mao yunlong he Ming Su Wenyan Zhang School of Marine Sciences Sun Yat-sen UniversityZhuhai 519082China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai 519082China Hubei Key Laboratory of Marine Geological Resources China University of GeosciencesWuhan 430074China School of Resources and Environmental Engineering Guizhou Institute of TechnologyGuiyang 550003China Institute of Coastal Research Helmholtz-Zentrum GeesthachtGeesthacht 21502Germany

Submarine canyon systems are sites for coarser clastic sediment accumulations in the deep-water domains, having the most potential for hydrocarbon reservoirs. Based on the interpretation of high resolution 2 D/3 D seismic and drilling data, depositional characteristics of three large deep-water canyon systems on the South China Sea northern margin have been analyzed. The Central Canyon System has a deep incision geomorphology extending from east to west, featured by distinct canyon segmentations, multi-provenance sediment supplies and multi-stage canyon fillings. The Pearl River Canyon System’s formation is closely related to the development of Pearl River Delta. Its vertical stacking and migrating canyon patterns have changed over time. The depositional architectures and evolution of the recent Penghu-Gaoping Canyon System respond to tectonic movements along the Taiwan-Luzon convergent continental margin. The main controlling factors of the formation and evolution of these three canyon systems include the tectonic setting, sediment supply, sea level change and paleo-geomorphology, among which the former two are dominant. The Penghu-Gaoping Canyon System formed along the subduction structural zone, directly indicating a typical tectonic origin. Numerous seismic data show that the Central Canyon and Pearl River Canyon systems are obviously affected by tectonics, associated local topography and sediment supply.

关键词： deep-water canyon system turbidite channel deep-water reservoir northern margin of South China Sea

Effects and mechanism of freeze-thawing cycles on the soil N2O fluxes in the temperate semi-arid steppe

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Journal of Environmental Sciences 2017年第6期29卷 192-201页

作者： Liqin Wang Yuchun Qi Yunshe Dong qin Peng Shufang Guo yunlong he Zhaolin Li Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China University of the Chinese Academy of Sciences Beijing 100049China

High nitrous oxide （N20） emissions during freeze-thawing period （FFP） have been observed in many different ecosystems. However, the knowledge about the dynamic of soil N20 emissions and its main driving mechanism during the freeze-thawing processes in grassland ecosystem is still limited. An in-situ experiment was conducted during the FTP on the sites with 0 and 15% surplus of the average rainfall and two levels of N addition （0,10 g N/（m2-year）） during growing season （marked as WON0, WISN0, WONI0, WISNI0, respectively） to explore the effects of water and N background on soil N20 emissions during FTPs and the relationship between soil N20 emissions and environmental factors. The results indicated that water and N treatments conducted during growing season did not show significant effect on the N20 effluxes of FTP, but the soil mineral N contents of WONI0 treatment were significantly higher than those of WON0, WI5N0, WI5NI0 treatments （p 〈 0.05）. The soil PLFA concentrations of microbial groups monitored during 2015 spring freeze-thawing period （2015S-FTP） were lower than those during winter freeze-thawing period of 2014 （2014W-FTP）, while cumulative soil N20 emissions of 2015S-FTP were higher than those of 2014W-FFP. The correlations between soil N20 effluxes and most of the measured environmental factors were insignificant, multiple stepwise regression analysis indicated that the soil temperature, soil NH$-N content and air temperature were the major environmental factors which significantly influenced the N20 effluxes during 2014W-FTP, and air temperature and son water content were the significant influencing factors during 2015S-FTP.

关键词： Temperate semi-arid steppeNitrous oxideFreeze-thawing periodWater and nitrogen addition

Key problems and solutions in arch dam heightening

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Frontiers of Structural and Civil Engineering 2011年第1期5卷 98-104页

作者： Zuoguang FU yunlong he Sheng SU College of Water Resources and Hydroelectric Engineering Wuhan UniversityWuhan 430072China

The dam heightening,which is an effective way to increase reservoir volume,has been paid close attention by *** problems should be dealt with when an arch dam needs to be heightened:stress state getting worse at dam heel,cracking on new added concrete dam surface,and weak bonding between new added concrete and old *** Geba arch dam as an example,these problems are examined in details through simulation analysis by the finite element *** tensile stresses on dam’s surface and joint face that have certain relations to the dam heightening can be controlled by some measures.

关键词： arch dam heighten tensile stress finite element method

ASRNet: Adversarial Segmentation and Registration Networks for Multispectral Fundus Images

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Computer Systems Science & Engineering 2021年第3期36卷 537-549页

作者： Yanyun Jiang Yuanjie Zheng Xiaodan Sui Wanzhen Jiao yunlong he Weikuan Jia School of Information Science and Engineering Shandong Normal UniversityJinan250358China Key Laboratory of Intelligent Computing&Information Security in Universities of Shandong Shandong Provincial Key Laboratory for Novel Distributed Computer Software TechnologyInstitute of Biomedical SciencesShandong Normal UniversityJinan250358China Shandong Provincial Hospital Affiliated to Shandong University Jinan250021China INSA Lyon University of LyonCNRSInsermVilleurbanne69621CedexFrance

Multispectral imaging (MSI) technique is often used to capture imagesof the fundus by illuminating it with different wavelengths of light. However,these images are taken at different points in time such that eyeball movementscan cause misalignment between consecutive images. The multispectral imagesequence reveals important information in the form of retinal and choroidal bloodvessel maps, which can help ophthalmologists to analyze the morphology of theseblood vessels in detail. This in turn can lead to a high diagnostic accuracy of several diseases. In this paper, we propose a novel semi-supervised end-to-end deeplearning framework called “Adversarial Segmentation and Registration Nets”(ASRNet) for the simultaneous estimation of the blood vessel segmentation andthe registration of multispectral images via an adversarial learning process. ASRNet consists of two subnetworks: (i) A segmentation module S that fulfills theblood vessel segmentation task, and (ii) A registration module R that estimatesthe spatial correspondence of an image pair. Based on the segmention-drivenregistration network, we train the segmentation network using a semi-supervisedadversarial learning strategy. Our experimental results show that the proposedASRNet can achieve state-of-the-art accuracy in segmentation and registrationtasks performed with real MSI datasets.

关键词： Deep learning deformable image registration image segmentation multispectral imaging(MSI)

Joint Deep Matching Model of OCT Retinal Layer Segmentation

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Computers, Materials & Continua 2020年第6期63卷 1485-1498页

作者： Mei Yang Yuanjie Zheng Weikuan Jia yunlong he Tongtong Che Jinyu Cong School of Information Science and Engineering at Shandong Normal University Jinan250358China Key Lab of Intelligent Computing and Information Security in Universities of Shandong Shandong Provincial Key Laboratory for Novel Distributed Computer Software TechnologyInstitute of Biomedical SciencesShandong Normal UniversityJinan250358China INSA Lyon University of LyonCNRSInsermVilleurbanne69621 CedexFrance

Optical Coherence Tomography(OCT)is very important in medicine and provide useful diagnostic *** retinal layer thicknesses plays a vital role in pathophysiologic factors of many ocular *** the existing retinal layer segmentation approaches,learning or deep learning-based methods belong to the ***,most of these techniques rely on manual-marked layers and the performances are limited due to the image *** order to overcome this limitation,we build a framework based on gray value curve matching,which uses depth learning to match the curve for semi-automatic segmentation of retinal layers from *** depth convolution network learns the column correspondence in the OCT image *** whole OCT image participates in the depth convolution neural network operation,compares the gray value of each column,and matches the gray value sequence of the transformation column and the next *** this algorithm,when a boundary point is manually specified,we can accurately segment the boundary between retinal *** experimental results obtained from a 54-subjects database of both normal healthy eyes and affected eyes demonstrate the superior performances of our approach.

关键词： OCT retinal segmentation deep learning 1D convolution

Confining pressure effect on dynamic response of high rockfill dam

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Frontiers of Structural and Civil Engineering 2010年第1期4卷 116-126页

作者： Xuexing CAO yunlong he Kun XIONG State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

Studies show that the dynamic properties of rockfill are strongly dependent on the confining ***,confining pressure effect has become a very important factor in the seismic analysis of high rockfill *** relationships of dynamic shear modulus versus dynamic shear strain and damping ratio versus dynamic shear strain had been improved to a certain degree on the basic of widely used Hardin-Drnevich constitutive model in this *** a new model that could consider confining pressure effect has been *** analysis was carried out of the dynamic triaxial experimental data of the damming materials in the Changheba hydropower station of Sichun Province,*** results show that,the new model can fit the test data well under various confining pressures.A corresponding computational procedure was compiled and applied in the dynamic response analysis of the Changheba *** the calculation results between the new constitutive model and the ordinary Hardin-Drnevich model,it can be seen that the result is conservative to some extent without considering confining pressure effect.

关键词： confining pressure effect high rockfill dam dynamic response Hardin-Drnevich constitutive model

Influences of drip and flood irrigation on soil carbon dioxide emission and soil carbon sequestration of maize cropland in the North China Plain

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Journal of Arid Land 2017年第2期9卷 222-233页

作者： GUO Shufang QI Yuchun PENG Qin DONG Yunshe he yunlong YAN Zhongqing WANG Liqin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

The need is pressing to investigate soil CO2 （carbon dioxide） emissions and soil organic carbon dynamics under water-saving irrigation practices in agricultural systems for exploring the potentials of soil carbon sequestration. A field experiment was conducted to compare the influences of drip irrigation （DI） and flood irrigation （FI） on soil organic carbon dynamics and the spatial and temporal variations in CO2 emissions during the summer maize growing season in the North China Plain using the static closed chamber method. The mean CO2 efflux over the growing season was larger under DI than that under FI. The cumulative CO2 emissions at the field scale were 1959.10 and 1759.12 g/m2 under DI and FI, respectively. The cumulative CO2 emission on plant rows （OR） was larger than that between plant rows （BR） under FI, and the cumulative CO2 emission on the irrigation pipes （OP） was larger than that between irrigation pipes （BP） under DI. The cumulative CO2 emissions of OP, BP and bare area （BA） under DI were larger than those of OR, BR and BA under FI, respectively. Additionally, DI promoted root respiration more effectively than FI did. The average proportion of root respiration contributing to the soil CO2 emissions of OP under DI was larger than that of OR under FI. A general conclusion drawn from this study is that soil CO2 emission was significantly influenced by the soil water content, soil temperature and air temperature under both DI and FI. Larger concentrations of dissolved organic carbon （DOC）, microbial biomass carbon （MBC） and total organic carbon （TOC） were observed under FI than those under DI. The observed high concentrations （DOC, MBC, and TOC） under FI might be resulted from the irrigation-associated soil saturation that in turn inhibited microbial activity and lowered decomposition rate of soil organic matter. However, DI increased the soil organic matter quality （the ratio of MBC to TOC） at the depth of 10-20 cm compared with FI. Our results suggest t

关键词： drip irrigation flood irrigation spatio-temporal variation carbon dioxide soil organic carbon North China Plain

Difference in full-filled time and its controlling factors in the Central Canyon of the Qiongdongnan Basin

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Acta Oceanologica Sinica 2015年第10期34卷 81-89页

作者： SHANG Zhilei XIE Xinong LI Xushen ZHANG Daojun he yunlong YANG Xing CUI Mingzhe Key Laboratory of Tectonics & Petroleum Resources of Ministry of Education China University of Geosciences Zhanjiang Branch of China National Offshore Oil Corporation(CNOOC) Limited Hubei Shale Gas Development Co. Ltd. Bohai Oilfield Research Institute Tianjin Branch of CNOOC Limited

Based on the interpretation of high resolution 2D/3D seismic data, sedimentary filling characteristics and full- filled time of the Central Canyon in different segments in the Qiongdongnan Basin of northwestern South China Sea have been studied. The research results indicate that the initial formation age of the Central Canyon is traced back to 11.6 Ma （T40）, at which the canyon began to develop due to the scouring of turbidity currents from west to east. During the period of 11.6-8.2 Ma （T40-T31）, strong downcutting by gravity flow occurred, which led to the formation of the canyon. The canyon fillings began to form since 8.2 Ma （T31） and were dominated by turbidite deposits, which constituted of lateral migration and vertical superposition of turbidity channels during the time of 8.2-5.5 Ma. The interbeds of turbidity currents deposits and mass transport deposits （MTDs） were developed in the period of 5.5-3.8 Ma （T30-T28）. After then, the canyon fillings were primarily made up of large scale MTDs, interrupted by small scale turbidity channels and thin pelagic mudstones. The Central Canyon can be divided into three types according to the main controlling factors, geomorphology-controlled, fault-controlled and intrusion- modified canyons. Among them, the geomorphology-controlled canyon is developed at the Ledong, Lingshui, Songnan and western Baodao Depressions, situated in a confined basin center between the northern slope and the South Uplift Belt along the Central Depression Belt. The fault-controlled canyon is developed mainly along the deep-seated faults in the Changchang Depression and eastern Baodao Depression. Intrusion-modified canyon is only occurred in the Songnan Low Uplift, which is still mainly controlled by geomorphology, the intrusion just modified seabed morphology. The full-filled time of the Central Canyon differs from west to east, displaying a tendency of being successively late eastward. The geomorphology-controlled canyon was completely filled

关键词： South China Sea Qiongdongnan Basin Central Canyon sedimentary filling full-filled time