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Earthquake Electromagnetic Precursor Anomalies Detected by a New Ground-based Observation Network 被引量:9
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作者 Bing HAN Guoze ZHAO +6 位作者 Lifeng WANG Ji TANG Yaxin BI Yan ZHAN Xiaobin CHEN Qibin XIAO Jihong ZHANG 《Journal of Geodesy and Geoinformation Science》 2021年第1期116-123,共8页
It is a debated topic if there are any observable precursor anomalies prior to the earthquake(EQ hereafter)and if the stronger EQ can be successfully predicted.During last few decades quite a lot of observable electro... It is a debated topic if there are any observable precursor anomalies prior to the earthquake(EQ hereafter)and if the stronger EQ can be successfully predicted.During last few decades quite a lot of observable electromagnetic(EM)precursors were published by using techniques equipped in either satellites or on ground-based stations.But there are only a few cases that the shortterm precursor anomalies of EM field before earthquakes were observed by using alternate EM fields on ground.This paper will present a new EM observation network built in recent years and show a new finding of EM field with the variation of a one-year cycle observed using the network.As an example,the short-term precursor anomalies of apparent resistivity before the Yangbi EQ(Ms 5.1)occurred on March 27,2017 in Yunnan Province will be studied.The observed anomalous phenomena indicate that the anomaly before the EQ can be captured only if reasonable effective methods including sophisticated analytical techniques are used,and it is believed that continuously observed data on the fixed observation network for a long time is an effective means for studying anomalies that appeared before earthquakes.This network can also play an important role in studying the EM environment from space. 展开更多
关键词 electromagnetic observation network natural EM phenomena precursor anomaly apparent resistivity space EM environment
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Collaborative Assessment of Reflectivity Consistency between FY-3G Precipitation Measurement Radar and Ground-Based Radars
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作者 Chunyan ZHANG Heng HU +4 位作者 Jiashan ZHU Qinqiang ZHOU Lei WU Jianyong LI Xuan ZHU 《Advances in Atmospheric Sciences》 2026年第5期1065-1078,共14页
FY-3G is the first polar-orbiting satellite equipped with a precipitation measurement radar(PMR)operating at Ku-andKa-band frequencies in China.In this study,we compare the reflectivity data from the FY-3G PMR Ku prod... FY-3G is the first polar-orbiting satellite equipped with a precipitation measurement radar(PMR)operating at Ku-andKa-band frequencies in China.In this study,we compare the reflectivity data from the FY-3G PMR Ku product and groundbasedradars(GRs)during 2024.Also,the FY-3G PMR is used as a third-party reference to evaluate the reflectivityconsistency among different GRs.The FY-3G PMR and GRs share similarities in their general distribution,characteristics,and intensity of reflectivity in strong precipitation cloud systems,though the former presents less detailed system structure.Systematic deviations between the FY-3G PMR and GRs and between GRs are comparable,albeit the reflectivity of the FY-3G PMR is generally slightly stronger than that of GRs(especially X-band GRs),with a mean bias ranging from 0.7 to 1.7dB.S-band GRs exhibit the smallest systematic deviation(STD=3.09 dB)from the FY-3G PMR,whereas the X-band GRsshow the largest(STD=3.61 dB),indirectly indicating the highest internal consistency among S-band GRs and the lowestamong X-band GRs.Besides,both S-and C-band GRs display similar deviations when paired with the FY-3G PMR as wellas when paired with their adjacent S/C-band GRs,suggesting good consistency between these two bands.In contrast,XbandGRs exhibit relatively poor consistency with S-band GRs and the FY-3G PMR,showing a deviation ranging from 3.0to 4.6 dB. 展开更多
关键词 REFLECTIVITY deviation CONSISTENCY FY-3G PMR ground-based radars
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Observation and research on small solar system bodies based on the Antarctic Tianmu Staring Observation Project
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作者 JianChun Shi Xian Shi +8 位作者 Man-To Hui Anton Pomazan Jian-Yang Li Ning Liu YingQi Wu Dan Zhou Jing Zhong ZhengHong Tang ShiYin Shen 《Earth and Planetary Physics》 2026年第2期349-354,共6页
The Antarctic Tianmu Staring Observation Project(ATSOP)entails the deployment of 30 small-aperture,wide-field optical telescopes in the Antarctic region.The system will perform long-term continuous observation campaig... The Antarctic Tianmu Staring Observation Project(ATSOP)entails the deployment of 30 small-aperture,wide-field optical telescopes in the Antarctic region.The system will perform long-term continuous observation campaigns over a period of 100 d(24 h per day)per year,as well as short-time-scale sampling at intervals of 5 min,across a sky area of approximately 1200 square degrees centered near the south celestial pole.We have assessed the types of small solar system bodies detectable by the ATSOP telescopes,as well as the associated scientific research opportunities.Our analysis indicates that the ATSOP is capable of detecting near-Earth objects(NEOs)with all orbital inclinations,as well as high-inclination small bodies located beyond the main asteroid belt.Potential research topics include the discovery and identification of small bodies,orbit determination,physical characterization,investigation into the activity characteristics and evolutionary patterns of active small bodies,and studies on their dynamical evolution.Observations of NEOs can also contribute to planetary defense efforts.On the basis of pilot observational data collected by the Antarctic Tianmu prototype(AT-Proto)between February 20 and October 26,2023,a total of 478 asteroids and 9 comets were successfully identified,demonstrating the effectiveness of the ATSOP system in observing small solar system bodies.Looking ahead,with anticipated performance enhancements in the second-generation AT-Proto,the limiting magnitude will increase from 16 to 18,thereby enabling the detection of an even greater number of small solar system bodies. 展开更多
关键词 Antarctic Tianmu Staring observation Project small solar system bodies observational techniques survey
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Earth Observation for Environmental Security:Emerging Multi-Sensor Fusion Techniques
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作者 Changjiang Cai Lei Gao +2 位作者 Minkuo Cai Fachun She Ruijie Wang 《Journal of Environmental & Earth Sciences》 2026年第3期91-111,共21页
Climate change,natural disasters,pollution,and fast urbanization have made environmental security a more serious international issue.Timely,accurate,and multi-dimensional information is essential in the effective moni... Climate change,natural disasters,pollution,and fast urbanization have made environmental security a more serious international issue.Timely,accurate,and multi-dimensional information is essential in the effective monitoring and management of such complex challenges in the environment.The Earth Observation(EO)systems,including optical sensors,radar sensors,Light Detection and Ranging(LiDAR)sensors,thermal sensors,Unmanned Aerial Vehicle(UAV)sensors,and in-situ sensors,offer a good coverage of space and time,as well as provide useful information on land,water,and atmospheric processes.But the shortcomings or weaknesses of individual sensors,such as their vulnerability to weather conditions,spectral or spatial resolution,and gaps in time,can tend to limit their ability to provide a complete picture of the environment.One of the solutions has been multi-sensor fusion,which combines heterogeneous data and makes it more accurate,robust,and interpretable.This systematic review analyzes the latest methods of multi-sensor fusion,which are machine learning,deep learning,probabilistic models,and hybrid approaches,in terms of methodological principles,preprocessing needs,and computational frameworks.Applications in environmental security are highlighted,which include monitoring natural disasters,monitoring of climate and ecosystem,pollution monitoring,monitoring of land use change,and early warning systems.The review also covers evaluation measures,validation plans,and uncertainty measures,where a strict measure of evaluation is vital to making actionable decisions.Lastly,emerging issues,e.g.,data heterogeneity,computational needs,sensor interoperability,and prospects in the future,e.g.,AI-based adaptive fusion,UAVs and Internet of Things(IoT)integration,and scalable cloud-based systems,are discussed.The synthesis has highlighted the transformational capability of multi-sensor EO in terms of improving the environment in the context of environmental security and sustainable management. 展开更多
关键词 Earth observation Environmental Security Multi-Sensor Fusion Remote Sensing Data Integration
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Observation on the Efficacy and Mechanism of Blood-Letting and Cupping Therapy in Improving Upper Limb Lymphedema after Breast Cancer Surgery
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作者 Dongli Zhang Jia Liu Qian Zheng 《Proceedings of Anticancer Research》 2026年第1期115-121,共7页
Objective:To evaluate the clinical efficacy of blood-letting cupping combined with manual lymphatic drainage in treating breast cancer-related lymphedema(BCRL)and explore its mechanism of action from both traditional ... Objective:To evaluate the clinical efficacy of blood-letting cupping combined with manual lymphatic drainage in treating breast cancer-related lymphedema(BCRL)and explore its mechanism of action from both traditional Chinese medicine and modern medical perspectives,providing a scientific basis and novel therapeutic approaches for clinical management of BCRL.Methods:Patients with BCRL admitted to the outpatient and inpatient departments of Hebei University Affiliated Hospital were enrolled.A prospective randomized controlled trial design was adopted,with eligible patients randomly assigned to a treatment group and a control group.The control group received manual lymphatic drainage alone,while the treatment group received manual lymphtic drainage combined with blood-letting cupping therapy.Posttreatment comparisons evaluated upper limb circumference reduction,edema severity grading,and upper limb functional scores.Vital signs and adverse reactions during treatment were recorded for both groups.Statistical software analyzed the data.Results:The treatment group demonstrated significantly greater reduction in upper limb circumference,improvement in edema severity,and higher upper limb function scores compared to the control group(P<0.05).Vital signs remained stable throughout treatment in both groups.No severe adverse reactions occurred in the treatment group;only isolated cases of mild skin itching were reported,which resolved after symptomatic management.Conclusion:The combination of bloodletting cupping and manual lymphatic drainage demonstrates reliable efficacy in treating BCRL,effectively alleviating edema symptoms and improving upper limb function with high safety.Its mechanism may relate to traditional Chinese medicine principles of“unblocking meridians,promoting blood circulation,and resolving stasis”and modern medical concepts of“enhancing local blood circulation,facilitating lymphatic drainage,and reducing inflammatory responses”. 展开更多
关键词 Blood-letting cupping Postoperative breast cancer Upper limb lymphedema Efficacy observation Mechanism of action
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Simultaneous lidar observations of the sporadic Ni layer and sporadic Na layer in the MLT
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作者 ZhiJun Zhao XuYang Jiang +3 位作者 FuJu Wu YuHang Qi Jing Jiao GuoTao Yang 《Earth and Planetary Physics》 2026年第1期156-166,共11页
Here we report on simultaneous lidar observations of sporadic Ni(Nis)layers and sporadic Na(Nas)layers in the atmosphere over Yanqing,Beijing(40.42°N,116.02°E)from April 2019 to October 2022.During 343 night... Here we report on simultaneous lidar observations of sporadic Ni(Nis)layers and sporadic Na(Nas)layers in the atmosphere over Yanqing,Beijing(40.42°N,116.02°E)from April 2019 to October 2022.During 343 nights of observation,68 Nis and 56 Nas were observed.The seasonal variation of Nis and Nas was also obtained,with the highest occurrence of Nis being in July(43%)and that of Nas being in June(61%).We found that the seasonal variation of Nis is similar to that of Nas and that both occur more frequently in summer than in winter.In addition,we found 23 events in which Nis and Nas occur simultaneously.The average peak altitude of Nas is approximately 1 km higher than that of Nis,and the peak density ratio of Nas to Nis is approximately 5,which is half the density ratio of the two main layers.Additionally,the strength factor for Nas is smaller than that for Nis.Through data analysis of sporadic E layers(Es),we found that Nis and Nas has a significant correlation with Es.The neutralization rates of Ni^(+)/Na^(+)were calculated according to the dissociative recombination reaction of Ni^(+)/Na^(+)and the WACCM-Ni(Whole Atmosphere Community Climate Model of Ni).The production rates of Ni and Na were estimated to be approximately 1:4.4,which is consistent with the density ratio of Nis to Nas.The results showed that the neutralization reaction of Ni+,Na+,and electrons in Es is the main reason for the formation of the Nis layer and the Nas layer. 展开更多
关键词 lidar observation sporadic Ni layer sporadic Na layer sporadic E layer seasonal variation
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Observation of Typhoon Trami(2024)-induced energy cascade from near-inertial waves to diurnal internal tides
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作者 Letian Chen Ze Zhang +4 位作者 Yifei Jiang Xiaojiang Zhang Jiagen Li Weimin Zhang Huizan Wang 《Atmospheric and Oceanic Science Letters》 2026年第2期74-81,共8页
Energy transfers among internal waves in the northern South China Sea are not well characterized,particularly during typhoons,owing to the lack of in situ observations.Based on high-resolution mooring data collected d... Energy transfers among internal waves in the northern South China Sea are not well characterized,particularly during typhoons,owing to the lack of in situ observations.Based on high-resolution mooring data collected during Typhoon Trami(2024),this study reveals the occurrence of robust vertical energy redistribution among diurnal internal tides(D1 ITs)and near-inertial waves(NIWs).Strikingly,the typhoon not only amplified the NIW energy but also triggered an unexpected surge in the D1 IT energy.The observed average net energy transfer rate of 1×10^(-7) W kg^(−1) from typhoon-forced NIWs to D1 ITs occurred at water depths of 120-170 m.Further bispectral analysis indicated that the energy transfer is driven by nonlinear wave—wave interaction.These results reveal the existence of a new energy transfer pathway—from atmospheric forcing to D1 ITs—and redefine the redistribution of the internal wave energy during extreme weather events. 展开更多
关键词 Tropical cyclones Mooring observation Near-inertial waves Energy cascade Diurnal internal tides South China Sea
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State Field Observation and Research Station of Debris Flow in Dongchuan,Yunnan,China
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《Journal of Mountain Science》 2026年第3期F0003-F0003,共1页
State Field Observation and Research Station of Debris Flow in Dongchuan,Yunnan is also named Dongchuan Debris Flow Observation and Research Station,Chinese Academy of Sciences.The study area,Jiangjia Ravine,is about ... State Field Observation and Research Station of Debris Flow in Dongchuan,Yunnan is also named Dongchuan Debris Flow Observation and Research Station,Chinese Academy of Sciences.The study area,Jiangjia Ravine,is about 48.6 km2 and characterized by intense tectonism.Accumulated clastic detritus is the main source of the materials in the debris flows when an intense rainfall occurs.The recorded highest density and sediment transport are 2370 kg/m^(3) and 6.079×10^(6) kg/s,respectively.The ravine is now called the“debris flow museum”in China and supplies advantageous research conditions. 展开更多
关键词 observation station sediment transport highest density intense tectonismaccumulated clastic detritus debris flows Dongchuan research station
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In situ/operando observation and phase field simulation of lithium dendrite:Progress and prospects
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作者 Li-Ting Gao Zhan-Sheng Guo 《Journal of Energy Chemistry》 2026年第2期91-112,I0004,共23页
Lithium metal batteries(LMBs)represent a promising solution for next-generation energy storage due to their high energy density,but the growth of lithium dendrites presents significant challenges to their performance ... Lithium metal batteries(LMBs)represent a promising solution for next-generation energy storage due to their high energy density,but the growth of lithium dendrites presents significant challenges to their performance and safety.This review provides a comprehensive overview of the mechanisms behind lithium dendrite formation and the role of in situ/operando observation and phase field simulation in understanding and mitigating this issue,The key driving factors of dendrite growth,such as lithium-ion flux heterogeneity,surface defects,and localized stress,are explored through advanced experimental techniques,which enable real-time visualization of dendrite nucleation and growth dynamics.Complementarily,phase field simulations provide insights into subsurface and temporal evolution of dendrites by modeling thermodynamic and kinetic processes,while machine learning techniques optimize simulation accuracy through data-driven parameter refinement.The integration of experimental observations with simulation models holds great potential in improving understanding and predictive capabilities.Despite ongoing progress,challenges remain in resolving technical limitations in observation techniques,improving computational efficiency,and fostering interdisciplinary collaboration.This review highlights the synergy between experimental and computational strategies in advancing the development of LMBs and calls for continued research to overcome existing hurdles and unlock the full potential of lithium metal anodes. 展开更多
关键词 Lithium metal batteries Lithium dendrite growth In situ/operando observation Phase field method Machine learning
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Mobile Observations of Intracity Variations in Atmospheric CO_(2)and CH_(4)
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作者 Jun WANG Wei XIAO +7 位作者 Ning HU Ruonan LI Honghui XU Yibo LIU Lingbing BU Longlong CHEN Yuanze LIU Xuhui LEE 《Advances in Atmospheric Sciences》 2026年第5期1033-1047,I0034-I0038,共20页
The spatial variability in the atmospheric CO_(2)and CH_(4)concentrations in urban land is affected by the source type,source distribution,and emission intensity in the cityscape.In this study,we analyzed vehicle-moun... The spatial variability in the atmospheric CO_(2)and CH_(4)concentrations in urban land is affected by the source type,source distribution,and emission intensity in the cityscape.In this study,we analyzed vehicle-mounted measurements of street-level CO_(2)and CH_(4)concentrations in Hangzhou—a large metropolitan area in the Yangtze River Delta in eastern China.The results revealed that CO_(2)and CH_(4)emission hotspots did not overlap geographically,with the former occurring as linear features at elevated road intersections and expressways and the latter occurring at waste treatment facilities(sewage treatment plants and landfills).The CH_(4):CO_(2)emission ratios(ppb ppm^(-1))were ranked in increasing order as follows:traffic(1.01±1.82;mean±1 SD);overall(3.46±2.71);sewage treatment(12.76±2.50);and landfill(36.50±10.15).Waste treatment was largely responsible for the increased overall emission ratio,supporting this source category as a major contributor to the CH_(4)budget in this city and suggesting a negligible role of domestic appliances(cookstoves and water heaters).A two-source mixing model calculation indicated that 99.9%of nonelectric vehicles in Hangzhou were gasoline-powered,revealing a recent shift in vehicle fuel composition from gasoline/natural gas to gasoline/electricity.The methodology established in this study is applicable to cities elsewhere. 展开更多
关键词 CH_(4)and CO_(2) vehicle-mounted observations emission hotspots CH_(4):CO_(2)emissions ratio emission source composition
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Comparison of Precipitation Observations from a Prototype Space-based Cloud Radar and Ground-based Radars 被引量:6
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作者 刘黎平 张志强 +3 位作者 于丹茹 杨虎 赵崇辉 仲凌志 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第6期1318-1329,共12页
A prototype space-based cloud radar has been a precipitation system over Tianjin, China in July developed and was installed on an airplane to observe 2010. Ground-based S-band and Ka-band radars were used to examine t... A prototype space-based cloud radar has been a precipitation system over Tianjin, China in July developed and was installed on an airplane to observe 2010. Ground-based S-band and Ka-band radars were used to examine the observational capability of the prototype. A cross-comparison algorithm between different wavelengths, spatial resolutions and platform radars is presented. The reflectivity biases, correlation coefficients and standard deviations between the radars are analyzed. The equivalent reflectivity bias between the S- and Ka-band radars were simulated with a given raindrop size distribution. The results indicated that reflectivity bias between the S- and Ka-band radars due to scattering properties was less than 5 dB, and for weak precipitation the bias was negligible. The prototype space-based cloud radar was able to measure a reasonable vertical profile of reflectivity, but the reflectivity below an altitude of 1.5 km above ground level was obscured by ground clutter. The measured refiectivity by the prototype space-based cloud radar was approximately 10.9 dB stronger than that by the S-band Doppler radar (SA radar), and 13.7 dB stronger than that by the ground-based cloud radar. The reflectivity measured by the SA radar was 0.4 dB stronger than that by the ground-based cloud radar. This study could provide a method for the quantitative examination of the observation ability for space-based radars. 展开更多
关键词 space-based cloud radar observational capability field experiment cloud observation
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Ground-Based Atmospheric CO_(2),CH_(4),and CO Column Measurements at Golmud in the Qinghai-Tibetan Plateau and Comparisons with TROPOMI/S5P Satellite Observations 被引量:2
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作者 Minqiang ZHOU Qichen NI +7 位作者 Zhaonan CAI Bavo LANGEROCK Jingyi JIANG Ke CHE Jiaxin WANG Weidong NAN Yi LIU Pucai WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第2期223-234,共12页
Measurements of carbon dioxide(CO_(2)),methane(CH_(4)),and carbon monoxide(CO)are of great importance in the Qinghai-Tibetan region,as it is the highest and largest plateau in the world affecting global weather and cl... Measurements of carbon dioxide(CO_(2)),methane(CH_(4)),and carbon monoxide(CO)are of great importance in the Qinghai-Tibetan region,as it is the highest and largest plateau in the world affecting global weather and climate systems.In this study,for the first time,we present CO_(2),CH_(4),and CO column measurements carried out by a Bruker EM27/SUN Fourier-transform infrared spectrometer(FTIR)at Golmud(36.42°E,94.91°N,2808 m)in August 2021.The mean and standard deviation of the column-average dry-air mixing ratio of CO_(2),CH_(4),and CO(XCO_(2),XCH_(4),and XCO)are 409.3±0.4 ppm,1905.5±19.4 ppb,and 103.1±7.7 ppb,respectively.The differences between the FTIR co-located TROPOMI/S5P satellite measurements at Golmud are 0.68±0.64%(13.1±12.2 ppb)for XCH_(4)and 9.81±3.48%(–10.7±3.8 ppb)for XCO,which are within their retrieval uncertainties.High correlations for both XCH_(4)and XCO are observed between the FTIR and S5P satellite measurements.Using the FLEXPART model and satellite measurements,we find that enhanced CH_(4)and CO columns in Golmud are affected by anthropogenic emissions transported from North India.This study provides an insight into the variations of the CO_(2),CH_(4),and CO columns in the Qinghai-Tibetan Plateau. 展开更多
关键词 ground-based FTIR greenhouse gas remote sensing TROPOMI/S5P Qinghai-Tibetan Plateau
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The First Ground-based White Light Lunar Polarization Imaging:A New Kind of FeO Observation on the Near Side of the Moon
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作者 Wei-Nan Wang Jin-Song Ping +4 位作者 Ming-Yuan Wang Wen-Zhao Zhang Han-Lin Ye Xing-Wei Han Song-Feng Kou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期1-6,共6页
Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes polarized.This study employs a novel split-focus plane polarimetric camera to conduct t... Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes polarized.This study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the Moon.We obtained the linear degree of polarization(DOP)parameters of white light by observation from the eastern and western hemispheres of the Moon.The findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria overall.Combining the analysis of lunar soil samples,we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the Moon.This study may serve as a new diagnostic tool for the Moon. 展开更多
关键词 techniques:photometric POLARIZATION methods:observational MOON
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Comparison of Reflectivity Consistency between Spaceborne Precipitation Radar and Ground-based Weather Radar in China and the United States 被引量:2
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作者 Peng CHEN Lin CHEN +3 位作者 Gang WANG Qiong WU Huiying WANG Peng ZHANG 《Advances in Atmospheric Sciences》 2025年第7期1376-1394,共19页
The Global Precipitation Measurement(GPM)dual-frequency precipitation radar(DPR)products(Version 07A)are employed for a rigorous comparative analysis with ground-based operational weather radar(GR)networks.The reflect... The Global Precipitation Measurement(GPM)dual-frequency precipitation radar(DPR)products(Version 07A)are employed for a rigorous comparative analysis with ground-based operational weather radar(GR)networks.The reflectivity observed by GPM Ku PR is compared quantitatively against GR networks from CINRAD of China and NEXRAD of the United States,and the volume matching method is used for spatial matching.Additionally,a novel frequency correction method for all phases as well as precipitation types is used to correct the GPM Ku PR radar frequency to the GR frequency.A total of 20 GRs(including 10 from CINRAD and 10 from NEXRAD)are included in this comparative analysis.The results indicate that,compared with CINRAD matched data,NEXRAD exhibits larger biases in reflectivity when compared with the frequency-corrected Ku PR.The root-mean-square difference for CINRAD is calculated at 2.38 d B,whereas for NEXRAD it is 3.23 d B.The mean bias of CINRAD matched data is-0.16 d B,while the mean bias of NEXRAD is-2.10 d B.The mean standard deviation of bias for CINRAD is 2.15 d B,while for NEXRAD it is 2.29 d B.This study effectively assesses weather radar data in both the United States and China,which is crucial for improving the overall consistency of global precipitation estimates. 展开更多
关键词 GPM DPR volume matching REFLECTIVITY ground-based radar
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In-situ observation of nonmetallic inclusions in steel using confocal scanning laser microscopy:A review 被引量:4
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作者 Ying Ren Lifeng Zhang 《International Journal of Minerals,Metallurgy and Materials》 2025年第5期975-991,共17页
The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are revi... The characteristics of nonmetallic inclusions formed during steel production have a significant influence on steel performance.In this paper,studies on inclusions using confocal scanning laser microscopy(CSLM)are reviewed and summarized,particularly the col-lision of various inclusions,dissolution of inclusions in liquid slag,and reactions between inclusions and steel.Solid inclusions exhibited a high collision tendency,whereas pure liquid inclusions exhibited minimal collisions because of the small attraction force induced by their<90°contact angle with molten steel.The collision of complex inclusions in molten steel was not included in the scope of this study and should be evaluated in future studies.Higher CaO/Al_(2)O_(3)and CaO/SiO_(2)ratios in liquid slag promoted the dissolution of Al_(2)O_(3)-based in-clusions.The formation of solid phases in the slag should be prevented to improve dissolution of inclusions.To accurately simulate the dissolution of inclusions in liquid slag,in-situ observation of the dissolution of inclusions at the steel-slag interface is necessary.Using a combination of CSLM and scanning electron microscopy-energy dispersive spectroscopy,the composition and morphological evolution of the inclusions during their modification by the dissolved elements in steel were observed and analyzed.Although the in-situ observa-tion of MnS and TiN precipitations has been widely studied,the in-situ observation of the evolution of oxide inclusions in steel during so-lidification and heating processes has rarely been reported.The effects of temperature,heating and cooling rates,and inclusion character-istics on the formation of acicular ferrites(AFs)have been widely studied.At a cooling rate of 3-5 K/s,the order of AF growth rate in-duced by different inclusions,as reported in literature,is Ti-O<Ti-Ca-Zr-Al-O<Mg-O<Ti-Zr-Al-O<Mn-Ti-Al-O<Ti-Al-O<Zr-Ti-Al-O.Further comprehensive experiments are required to investigate the quantitative relationship between the formation of AFs and inclusions. 展开更多
关键词 INCLUSION STEEL in-situ observation confocal scanning laser microscopy
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In-situ observation and analysis of high temperature behavior of carbides in GCr15 bearing steel by confocal laser scanning microscopy 被引量:2
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作者 Jun Ren Yue Teng +4 位作者 Xiang Liu Xi Xu Hui-gai Li Ke Han Qi-jie Zhai 《Journal of Iron and Steel Research International》 2025年第2期409-417,共9页
The high-temperature dissolution behavior of primary carbides in samples taken from GCr15 continuous-casting bloom was observed in-situ by confocal laser scanning microscopy.Equations were fitted to the dissolution ki... The high-temperature dissolution behavior of primary carbides in samples taken from GCr15 continuous-casting bloom was observed in-situ by confocal laser scanning microscopy.Equations were fitted to the dissolution kinetics of primary carbides during either heating or soaking.Dissolution of carbides proceeded in three stages(fast→slow→faster)as either temperature or holding time was increased.During the heating process and during the first and third stages of the soaking process,the original size of the carbides determined the steepness of the slope,but during the middle(“slow”)stage of the soaking process,the slope remained zero.The initial size of the carbides varied greatly,but their final dissolution temperature fell within the narrow range of 1210-1235℃,and the holding time remained within 50 min.Fractal analysis was used to study the morphological characteristics of small and medium-sized carbides during the dissolution process.According to changes in the fractal dimension before and after soaking,the carbides tended to evolve towards a more regular morphology. 展开更多
关键词 Bearing steel High-temperature confocal laser scanning microscope In-situ observation Primary carbide Fractal analysis
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Information carried by different magnetic observations:A review 被引量:1
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作者 David Gubbins 《Earth and Planetary Physics》 2025年第3期479-490,共12页
The Macao satellites differ from their predecessors in their orbits:MSS-1(Macao Science Satellite-1)is in low inclination and the planned MSS-2 will be in highly elliptical orbits.This paper reviews the fundamental ad... The Macao satellites differ from their predecessors in their orbits:MSS-1(Macao Science Satellite-1)is in low inclination and the planned MSS-2 will be in highly elliptical orbits.This paper reviews the fundamental advantages and disadvantages of the different possible magnetic measurements:the component(declination,intensity,etc.)and location(satellite,ground,etc.).When planning a survey the choice of component is the"What?"question;the choice of location the"Where?"question.Results from potential theory inform the choice of measurement and data analysis.For example,knowing the vertical component of magnetic field provides a solution for the full magnetic field everywhere in the potential region.This is the familiar Neumann problem.In reality this ideal dataset is never available.In the past we were restricted to declination data only,then direction only,then total intensity only.There have also been large swathes of Earth's surface with no measurements at all(MSS-1 is restricted to latitudes below).These incomplete datasets throw up new questions for potential theory,questions that have some intriguing answers.When only declination is known uniqueness is provided by horizontal intensity measurements on a single line joining the dip-poles.When only directions are involved uniqueness is provided by a single intensity measurement,at least in principle.Paleomagnetic intensities can help.When only total intensity is known,as was largely the case in the early satellite era,uniqueness is provided by a precise location of the magnetic equator.Holes in the data distribution is a familiar problem in geophysical studies.All magnetic measurements sample,to a greater or lesser extent,the potential field everywhere.There is a trade-off between measurements close to the source,good for small targets and high resolution,and the broader sample of a distant measurement.The sampling of a measurement is given by the appropriate Green's function of the Laplacian,which determines both the resolution and scope of the measurement.For example,radial and horizontal measurements near the Earth's surface give a weighted average of the radial component over a patch of the core surface beneath the measurement site about in radius.The patch is smaller for shallower surfaces,for example from satellite to ground.Holes in the data distribution do not correspond to similar holes at the source surface;the price paid is in resolution of the source.I argue that,in the past,we have been too reluctant to take advantage of incomplete and apparently hopeless datasets. 展开更多
关键词 GEOMAGNETISM satellite observation Macao Science Satellites-1
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Clinical observation of white eye distribution in patients with hyperlipidemia:an artificial intelligence digital visual examination technique 被引量:1
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作者 SONG Tianli LI Haixia LIU Li'an 《Journal of Traditional Chinese Medicine》 2025年第5期1135-1143,共9页
OBJECTIVE:To explore the clinical observation of white eye distribution characteristics of hyperlipidemic patients based on artificial intelligence digital eye diagnosis technology.METHODS:One hundred and fifty subjec... OBJECTIVE:To explore the clinical observation of white eye distribution characteristics of hyperlipidemic patients based on artificial intelligence digital eye diagnosis technology.METHODS:One hundred and fifty subjects were examined in the outpatient and inpatient departments of Guang'anmen Hospital of the China Academy of Traditional Chinese Medicine from 01 February 2022 to 01 February 2023,including 80 cases in the hyperlipidemic patient(HLP)group and 70 cases in the normal lipid level patient(NC)group.The two groups were collected and extracted by the artificial intelligence visual diagnostic instrument and analyzed by the MyEyeD-10 white eye shadowless imaging health intelligence analysis system.Finally,SPSS 26.0(Version X;IBM Corp.,Armonk,NY,USA)was used for statistical processing.RESULTS:Significant differences were noted in the scores of"spot"and"foggy"features between the two groups.Between groups,the"spot"feature score of the white eye morphology in the HLP group(11.07±3.22)was higher than that in the NC group(7.50±4.11)(P<0.01).Moreover,the"foggy"feature score of the eye morphology in the HLP group(8.37±2.25)was higher than that in the NC group(P<0.01),higher than that of the NC group(5.72±1.21)(P<0.05).There were significant differences in the"A"(stomach),"B","O"(spleen),and"M"(liver)eye-contact region scores between the two groups,and the"B","O"(spleen)and"M"(liver)eye-contact region scores were significantly different.The scores of the white eye channel region in the HLP group were significantly higher than those in the control group,with the"A","B",and"O"regions(P<0.01),"M"region(P<0.01),"A","B","O",and"M"region(P<0.01)."M"zone(P<0.05).The scores of"dull red"and"yellow"features were significantly different,and the scores of"dull red"and"yellow"colors of the white eye choroid in the HLP group were significantly higher than those in the HLP group.The scores of"dull red"and"yellow"were significantly higher in the HLP group than in the NC group(P<0.01).CONCLUSION:The morphological features of the white eye ocular image,the white eye chakra's color,and the bulbar conjunctiva's vascular zoning are closely related to hyperlipidemia.Importantly,these provide a reference for the objectivity and precision of the identification of Chinese medicine by looking at the eyes. 展开更多
关键词 HYPERLIPIDEMIAS white-eyed eye image eye complex features artificial intelligence clinical observation
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Extended state observer-based control with an adjustable parameter for a large ground-based telescope 被引量:2
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作者 Xiao-Xia Yang Yong-Ting Deng +1 位作者 Bin Zhang Jian-Li Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第12期509-518,共10页
The high-precision requirements will always be constrained due to the complicated operating conditions of the ground-based telescope. Owing to various internal and external disturbances, it is necessary to study a con... The high-precision requirements will always be constrained due to the complicated operating conditions of the ground-based telescope. Owing to various internal and external disturbances, it is necessary to study a control method, which should have a good ability on disturbance rejection and a good adaptability on system parameter variation. The traditional proportional-integral(PI) controller has the advantage of simple and easy adjustment, but it cannot deal with the disturbances well in different situations. This paper proposes a simplified active disturbance rejection control law, whose debugging is as simple as the PI controller, and with better disturbance rejection ability and parameter adaptability. It adopts a simplified second-order extended state observer(ESO) with an adjustable parameter to accommodate the significant variation of the inertia during the different design stages of the telescope. The gain parameter of the ESO can be adjusted online with a recursive least square estimating method once the system parameter has changed significantly. Thus, the ESO can estimate the total disturbances timely and the controller will compensate them accordingly. With the adjustable parameter of the ESO, the controller can always achieve better performance in different applications of the telescope. The simulation and experimental verification of the control law was conducted on a 1.2-meter ground based telescope. The results verify the necessity of adjusting the parameter of the ESO, and demonstrate better disturbance rejection ability in a large range of speed variations during the design stages of the telescope. 展开更多
关键词 extended state observer large ground based telescope recursive least square disturbance rejection
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Embedded solar adaptive optics telescope:achieving compact integration for high-efficiency solar observations 被引量:1
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作者 Naiting Gu Hao Chen +11 位作者 Ao Tang Xinlong Fan Carlos Quintero Noda Yawei Xiao Libo Zhong Xiaosong Wu Zhenyu Zhang Yanrong Yang Zao Yi Xiaohu Wu Linhai Huang Changhui Rao 《Opto-Electronic Advances》 2025年第5期60-74,共15页
Adaptive optics(AO)has significantly advanced high-resolution solar observations by mitigating atmospheric turbulence.However,traditional post-focal AO systems suffer from external configurations that introduce excess... Adaptive optics(AO)has significantly advanced high-resolution solar observations by mitigating atmospheric turbulence.However,traditional post-focal AO systems suffer from external configurations that introduce excessive optical surfaces,reduced light throughput,and instrumental polarization.To address these limitations,we propose an embedded solar adaptive optics telescope(ESAOT)that intrinsically incorporates the solar AO(SAO)subsystem within the telescope's optical train,featuring a co-designed correction chain with a single Hartmann-Shack full-wavefront sensor(HS f-WFS)and a deformable secondary mirror(DSM).The HS f-WFS uses temporal-spatial hybrid sampling technique to simultane-ously resolve tip-tilt and high-order aberrations,while the DSM performs real-time compensation through adaptive modal optimization.This unified architecture achieves symmetrical polarization suppression and high system throughput by min-imizing optical surfaces.A 600 mm ESAOT prototype incorporating a 12×12 micro-lens array HS f-WFS and 61-actuator piezoelectric DSM has been developed and successfully conducted on-sky photospheric observations.Validations in-cluding turbulence simulations,optical bench testing,and practical observations at the Lijiang observatory collectively confirm the system's capability to maintain aboutλ/10 wavefront error during active region tracking.This architectural breakthrough of the ESAOT addresses long-standing SAO integration challenges in solar astronomy and provides scala-bility analyses confirming direct applicability to the existing and future large solar observation facilities. 展开更多
关键词 embedded solar adaptive optics telescope(ESAOT) Hartmann-Shack full-wavefront sensor(HS f-WFS) deformable secondary mirror(DSM) high-resolution solar observations solar telescopes
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