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Automatic Road Tunnel Crack Inspection Based on Crack Area Sensing and Multiscale Semantic Segmentation

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Computers, Materials & Continua 2024年第4期79卷 1679-1703页

作者： Dingping Chen Zhiheng Zhu Jinyang Fu jilin He College of Mechanical and Electrical Engineering Central South UniversityChangsha410083China Department of Geotechnical Guangdong Hualu Transportation Technology Company LimitedGuangzhou510000China National Engineering Research Center of High-Speed Railway Construction Technology Changsha410075China

The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the surface of roadtunnels is the key to improving the maintenance efficiency of road tunnels. Machine vision technology combinedwith a deep neural network model is an effective means to realize the localization and identification of crackdefects on the surface of road *** propose a complete set of automatic inspection methods for identifyingcracks on the walls of road tunnels as a solution to the problem of difficulty in identifying cracks during manualmaintenance. First, a set of equipment applied to the real-time acquisition of high-definition images of walls inroad tunnels is designed. Images of walls in road tunnels are acquired based on the designed equipment, whereimages containing crack defects are manually identified and selected. Subsequently, the training and validationsets used to construct the crack inspection model are obtained based on the acquired images, whereas the regionscontaining cracks and the pixels of the cracks are finely labeled. After that, a crack area sensing module is designedbased on the proposed you only look once version 7 model combined with coordinate attention mechanism (CAYOLOV7) network to locate the crack regions in the road tunnel surface images. Only subimages containingcracks are acquired and sent to the multiscale semantic segmentation module for extraction of the pixels to whichthe cracks belong based on the DeepLab V3+ network. The precision and recall of the crack region localizationon the surface of a road tunnel based on our proposed method are 82.4% and 93.8%, respectively. Moreover, themean intersection over union (MIoU) and pixel accuracy (PA) values for achieving pixel-level detection accuracyare 76.84% and 78.29%, respectively. The experimental results on the dataset show that our proposed two-staged

关键词： Road tunnel crack inspection crack area sensing multiscale semantic segmentation CA-YOLO V7 DeepLab V3+

A Novel Sensing Imaging Equipment Under Extremely Dim Light for Blast Furnace Burden Surface:Starlight High-Temperature Industrial Endoscope

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 893-906页

作者： Zhipeng Chen Xinyi Wang Weihua Gui jilin Zhu Chunhua Yang Zhaohui Jiang The authors are with the School of Automation Central South UniversityChangsha 410083China

Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material charging control,optimize gas flow distribution and improve ironmaking *** has been challengeable to obtain high-quality optical burden surface images under high-temperature,high-dust,and extremelydim(less than 0.001 Lux)*** on a novel endoscopic sensing detection idea,a reverse telephoto structure starlight imaging system with large field of view and large aperture is *** with a water-air dual cooling intelligent self-maintenance protection device and the imaging system,a starlight high-temperature industrial endoscope is developed to obtain clear optical burden surface images stably under the harsh *** on an endoscope imaging area model,a material flow trajectory model and a gas-dust coupling distribution model,an optimal installation position and posture configuration method for the endoscope is proposed,which maximizes the effective imaging area and ensures large-area,safe and stable imaging of the device in a confined *** experiments and applications indicate that the proposed method obtains clear and reliable large-area optical burden surface images and reveals new BF conditions,providing key data support for green iron smelting.

关键词： Blast furnace(BF) burden surface extremely dim light industrial endoscope sensing imaging starlight

Diagnostic Analysis of Rainstorm and Backward Trajectory Simulation of Water Vapor in jilin Province in July,2010

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meteorological and Environmental Research 2011年第7期2卷 35-37,40页

作者： SUN Yan1,2,LUAN Meng3,JIANG Li3,CHEN Yang4 1.College of Atmospheric Science,Lanzhou University,Lanzhou 730000,china 2.jilin meteorological Observatory,changchun 13.062,china 3.jilin meteorological bureau,changchun 13.062,china 4.changchun meteorological Detection Center in jilin Province,changchun 13.062,china

[Objective] The research aimed to analyze the rainstorm process and backward trajectory simulation of water vapor condition in jilin Province in July,2010.[Method] Based on the actual situation data of routine weather chart,NCEP (2.5°×2.5°) reanalysis data per 6 h and GBL data of NOAA,the rainstorm process was carried out the diagnostic analysis of physical quantity in jilin Province in July,***,HYSPLIT backward trajectory mode was used to simulate the water vapor source.[Result] The coexistence of upper-level divergence and low-level convergence generated the ascending motion,which was the dynamic condition of rainstorm *** unstable energy induced by the low-level shear promoted the generation of heavy *** water vapor source of precipitation process was divided into the water vapor in the southern sea area,northern high-altitude water vapor transportation and local water vapor source.[Conclusion] The research provided some reference basis for the forecast and analysis of rainstorm.

关键词： Rainstorm Water vapor source Backward trajectory simulation Diagnostic analysis jilin Province china

Preparation of α-High Strength Gypsum from Flue Gas Desulfurization Gypsum Pretreated by Hydrothermal-aging Method

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 75-81页

作者：苏一鑫 GAO Lili 陈学青 LI Zhishui 李雲 CAO jilin Engineering Research Center of Seawater Utilization Technology of Ministry of Education School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Heze Center for Disease Control and Prevention Heze 274010China Tianjin Bohua Yongli Chemical Industry Co. Ltd.Tianjin 300452China

The synthesis of α-calcium sulfate hemihydrate (α-CSH) from flue gas desulfurization (FGD)gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtainα-CSH with the satisfactory performances, a facile hydrothermal-aging pretreatment process for FGD gypsum raw materials was proposed, where FGD gypsum was firstly hydrothermally converted to α-CSH whiskers, and α-CSH whiskers were further hydrated to synthesize CaSO4·2H2O (CSD) by aging under the regulation of N,N'-methylenebisacrylamide (MBA). The effects of aging time, MBA addition, aging temperature, and pH on the morphology of the synthesized CSD were investigated. The synthesized CSD crystals exhibit highly uniform prismatic morphology with the length of ca 100μm and the whiteness of 91.56%. The regulation mechanism of MBA was also illustrated. The synthesized CSD crystals with prismatic morphology were further used as raw materials to synthesize the short columnar α-CSH. The absolute dry compressive strength of paste prepared from the short columnar α-CSH is 40.85 MPa, which reaches α40 strength grade.

关键词： flue gas desulphurization gypsum α-calcium sulfate hemihydrate hydrothermal-aging method N,N'-methylenebisacrylamide prismatic CSD

Integrative multi-omics approaches reveal that Asian cultivated rice domestication influences its symbiotic relationship with arbuscular mycorrhizal fungi

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Pedosphere 2024年第2期34卷 315-327页

作者： Lei TIAN jilin WANG Hongping CHEN Weiqiang LI Lam-Son Phan TRAN Chunjie TIAN Key Laboratory of Mollisols Agroecology State Key Laboratory of Black Soils Conservation and UtilizationNortheast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Rice Research Institute Jiangxi Academy of Agricultural SciencesNanchang 330200China Institute of Genomics for Crop Abiotic Stress Tolerance Department of Plant and Soil ScienceTexas Tech UniversityLubbock TX 79409USA

Potential changes in the symbiotic relationship between rice(Oryza sativa)and microorganisms have occurred during the domestication of Asian cultivated rice(***)from common wild rice(Oryza rufipogon)and in response to global climate change,along with evolving adaptations to the *** potential genes may express differently or dominate the symbiotic relationships between arbuscular mycorrhizal fungi(AMF)and plants,which may be beneficial to rice *** date,research on this important topic has been *** this study,we aimed to examine the symbiotic relationships of Asian common wild and cultivated rice species with *** conducting a comparative metagenomic analysis of the rhizospheres of wild and cultivated rice species,we identified differences in Rhizophagus intraradices-related genes associated with wild and cultivated rice,as well as functional genes of ***,we obtained root-related genes associated with AMF from transcriptome data of rice *** results collectively suggest that ***-related genes in the rhizosphere of wild rice may be more conducive to its ***,bacteria from the Nitrosomonadaceae and Nitrospiraceae families identified in the rhizosphere of wild rice exhibited positive correlations with ***-related genes with protein identifiers 1480749 and1871253,which may indicate that nitrobacteria can enhance the functions of *** in association with wild ***,in a case study using comparative transcriptome analysis of root samples obtained from ***-inoculated wild and cultivated rice plants,we found significantly higher expression levels of the strigolactone pathway-related genes DWARF3(D3)and DWARF14(D14)in ***-inoculated common wild rice than in ***-inoculated cultivated *** study provides a theoretical basis for identifying the effects of domestication on mycorrhizal symbiosis-related genes,which could be promoted in wi

关键词： Rhizophagus intraradices root-related gene symbiotic effect strigolactone wild rice

Surface Water Resources' Response to Climate Changes in jilin Province

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meteorological and Environmental Research 2011年第7期2卷 53-56,65页

作者： CAI Zhe1,2,TAN Gui-rong2,SUN Li3,QU Jing-hua3 1.Jinan meteorological bureau,Jinan 250002,china 2.Key Laboratory of meteorological Disaster of Ministry of Education,Nanjing University of Information Science & Engineering,Nanjing 210044,china 3.jilin meteorological Scientific Research Institute,changchun 13.062,china

[Objective] The response of surface water resources on climate changes was studied.[Method] By dint of monthly average temperature and precipitation in 45 meteorological stations in jilin Province from 1960 to 2000,monthly runoff in 56 hydrological stations in Songhuajiang and Liaohe region,the surface runoff change and the response of surface water resources to climate change in 41 years were expounded.[Result] The runoff of Songliao region was limited during 1960s and *** began to increase slowly in the early *** 1990s,there were distinct fluctuation of annual runoff and it was decreasing in *** analysis suggested that the runoff of Songliao region was decreasing gradually from south to the *** central gradient was small and runoff was evenly *** test result showed that the annual runoff in Songliao region had large fluctuation before 1980s and after *** response of surface runoff on climate and precipitation changes in jilin Province was distinct and had strong relevance as well as certain *** on the analysis of the relation of rivers runoff and meteorological elements changes,statistics forecast model between river surface runoff and meteorological elements was *** prediction value and measured value had good *** corresponding river surface runoff changes can be assessed based on the changes of meteorological elements.[Conclusion] The study provided theoretical basis for the development and utilization of surface water resources in jilin.

关键词： Surface water resources Climate changes Response jilin china

CSST Dense Star Field Preparation:A Framework for Astrometry and Photometry for Dense Star Field Images Obtained by the china Space Station Telescope(CSST)

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Research in Astronomy and Astrophysics 2024年第7期24卷 158-169页

作者： Yining Wang Rui Sun Tianyuan Deng Chenghui Zhao Peixuan Zhao Jiayi Yang Peng Jia Huigen Liu jilin Zhou College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Astronomy&Space Science Nanjing UniversityNanjing 210093China Peng Cheng Lab Shenzhen 518066China

The china Space Station Telescope(CSST)is a telescope with 2 m diameter,obtaining images with high quality through wide-field *** its first observation cycle,to capture time-domain observation data,the CSST is proposed to observe the Galactic halo across different *** data have significant potential for the study of properties of stars and ***,the density of stars in the Galactic center is high,and it is a well-known challenge to perform astrometry and photometry in such a dense star *** paper presents a deep learning-based framework designed to process dense star field images obtained by the CSST,which includes photometry,astrometry,and classifications of targets according to their light curve *** simulated CSST observation data,we demonstrate that this deep learning framework achieves photometry accuracy of 2%and astrometry accuracy of 0.03 pixel for stars with moderate brightness mag=24(i band),surpassing results obtained by traditional ***,the deep learning based light curve classification algorithm could pick up celestial targets whose magnitude variations are 1.7 times larger than magnitude variations brought by Poisson photon *** anticipate that our framework could be effectively used to process dense star field images obtained by the CSST.

关键词： techniques photometric-methods data analysis-astrometry

Decoding the inconsistency of six cropland maps in china

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The Crop Journal 2024年第1期12卷 281-294页

作者： Yifeng Cui Ronggao Liu Zhichao Li Chao Zhang Xiao-Peng Song jilin Yang Le Yu Mengxi Chen Jinwei Dong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Geographical Sciences University of MarylandCollege ParkMD 20740USA College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Ministry of Education Ecological Field Station for East Asian Migratory Birds Department of Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Ministry of Education Ecological Field Station for East Asian Migratory Birds Beijing 100084China Tsinghua University(Department of Earth System Science)-Xi’an Institute of Surveying and Mapping Joint Research Center for Next-Generation Smart Mapping Beijing 100084China Institute of Remote Sensing and Geographic Information System Peking UniversityBeijing 100871China Department of Forest and Conservation Sciences University of British ColumbiaVancouverBCV6T 1Z4Canada

Accurate cropland information is critical for agricultural planning and production,especially in foodstressed countries like *** widely used medium-to-high-resolution satellite-based cropland maps have been developed from various remotely sensed data sources over the past few decades,considerable discrepancies exist among these products both in total area and in spatial distribution of croplands,impeding further applications of these *** factors influencing their inconsistency are also *** this study,we evaluated the consistency and accuracy of six cropland maps widely used in china in circa 2020,including three state-of-the-art 10-m products(i.e.,Google Dynamic World,ESRI Land Cover,and ESA WorldCover)and three 30-m ones(i.e.,GLC_FCS30,GlobeLand 30,and CLCD).We also investigated the effects of landscape fragmentation,climate,and agricultural *** using a ground-truth sample revealed that the 10-m-resolution WorldCover provided the highest accuracy(92.3%).These maps collectively overestimated Chinese cropland area by up to 56%.Up to 37%of the land showed spatial inconsistency among the maps,concentrated mainly in mountainous regions and attributed to the varying accuracy of cropland maps,cropland fragmentation and management practices such as *** work shed light on the promotion of future cropland mapping efforts,especially in highly inconsistent regions.

关键词： Consistency and accuracy 10-and 30 m Cropland mapping Agricultural management china

High-efficiency and flexible photonic microwave harmonic down-converter based on self-oscillation optical frequency combs

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Chinese Optics Letters 2024年第6期22卷 196-204页

作者： Xin Zhang Tao Pu Huatao Zhu Yunshan Zhang Gengze Wu Jin Li jilin Zheng College of Information and Communications National University of Defense TechnologyWuhan 430010China College of Communications Engineering Army Engineering University of PLANanjing 210007China College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China

Photonic microwave harmonic down-converters (PMHDCs) based on self-oscillation optical frequency combs (OFCs) are interesting because of their broad bandwidth compared with plain optoelectronic oscillators. In this paper, a high-efficiency and flexible PMHDC is proposed and demonstrated. The properties of the OFC, such as the carrier-to-noise ratio (CNR),bandwidth and free spectral range (FSR), and the influence of optical injection, are investigated. The broadband OFC provides a frequency tunable and high-quality local oscillation (LO), which guarantees flexible down-conversion for the radio frequency (RF) signal. The sideband selective amplification (SSA) effect not only improves the conversion efficiency but also promotes single-sideband modulation. The conversion range can reach 100 GHz. The 12–40 GHz RF signal can be downconverted to intermediate frequency (IF) signals with a high conversion efficiency of 14.9 dB. The fixed 40-GHz RF signal is flexibly down-converted to an IF signal with the frequency from 55.4 to 2129.4 MHz. The phase noise of an IF signal at a frequency offset of 10 kHz is the same as that of the input RF signal. The PMHDC shows great performance and will find applications in radio-over-fiber (RoF) networks, electronic warfare receivers, avionics, and wireless communication systems.

关键词： frequency down-conversion optical frequency comb optical injection optoelectronic oscillation