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Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China 被引量:1
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作者 WANG Zili LU Chunyan +4 位作者 SU Yanlin SU Yue YU Qianru LI Wenzhe YANG Nuocheng 《Chinese Geographical Science》 SCIE CSCD 2024年第1期135-148,共14页
Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human... Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In 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 forces.Taking 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 2001 to 2021.Combing 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 analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.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 role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development. 展开更多
关键词 winter urban heat island(UHI) rapid urbanization area land surface temperature(LST)retrieval profile analysis GeoDetector model Fuzhou City China
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Region-Aware Fashion Contrastive Learning for Unified Attribute Recognition and Composed Retrieval
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作者 WANG Kangping ZHAO Mingbo 《Journal of Donghua University(English Edition)》 CAS 2024年第4期405-415,共11页
Clothing attribute recognition has become an essential technology,which enables users to automatically identify the characteristics of clothes and search for clothing images with similar attributes.However,existing me... Clothing attribute recognition has become an essential technology,which enables users to automatically identify the characteristics of clothes and search for clothing images with similar attributes.However,existing methods cannot recognize newly added attributes and may fail to capture region-level visual features.To address the aforementioned issues,a region-aware fashion contrastive language-image pre-training(RaF-CLIP)model was proposed.This model aligned cropped and segmented images with category and multiple fine-grained attribute texts,achieving the matching of fashion region and corresponding texts through contrastive learning.Clothing retrieval found suitable clothing based on the user-specified clothing categories and attributes,and to further improve the accuracy of retrieval,an attribute-guided composed network(AGCN)as an additional component on RaF-CLIP was introduced,specifically designed for composed image retrieval.This task aimed to modify the reference image based on textual expressions to retrieve the expected target.By adopting a transformer-based bidirectional attention and gating mechanism,it realized the fusion and selection of image features and attribute text features.Experimental results show that the proposed model achieves a mean precision of 0.6633 for attribute recognition tasks and a recall@10(recall@k is defined as the percentage of correct samples appearing in the top k retrieval results)of 39.18 for composed image retrieval task,satisfying user needs for freely searching for clothing through images and texts. 展开更多
关键词 attribute recognition image retrieval contrastive language-image pre-training(CLIP) image text matching transformer
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Variation in the surface heat flux on the north and south slopes of Mount Qomolangma 被引量:1
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作者 Yonghao Jiang Maoshan Li +4 位作者 Yuchen Liu Ting Wang Pei Xu Yaoming Ma Fanglin Sun 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期28-33,共6页
The distinctive conditions present on the north and south slopes of Mount Qomolangma,along with the intricate variations in the underlying surfaces,result in notable variations in the surface energy flux patterns of t... The distinctive conditions present on the north and south slopes of Mount Qomolangma,along with the intricate variations in the underlying surfaces,result in notable variations in the surface energy flux patterns of the two slopes.In this paper,data from TESEBS(Topographical Enhanced Surface Energy Balance System),remote sensing data from eight cloud-free scenarios,and observational data from nine stations are utilized to examine the fluctuations in the surface heat flux on both slopes.The inclusion of MCD43A3 satellite data enhances the surface albedo,contributing to more accurate simulation outcomes.The model results are validated using observational data.The RMSEs of the net radiation,ground heat,sensible heat,and latent heat flux are 40.73,17.09,33.26,and 30.91 W m^(−2),respectively.The net radiation flux is greater on the south slope and exhibits a rapid decline from summer to autumn.Due to the influence of the monsoon,on the north slope,the maximum sensible heat flux occurs in the pre-monsoon period in summer and the maximum latent heat flux occurs during the monsoon.The south slope experiences the highest latent heat flux in summer.The dominant flux on the north slope is sensible heat,while it is latent heat on the south slope.The seasonal variations in the ground heat flux are more pronounced on the south slope than on the north slope.Except in summer,the ground heat flux on the north slope surpasses that on the south slope. 展开更多
关键词 Mount Qomolangma TESEBS model Remote sensing retrieval Surface heat fluxes
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An assessment of arctic sea ice concentration retrieval based on “HY-2” scanning radiometer data using field observations during CHINARE-2012 and other satellite instruments 被引量:7
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作者 SHI Lijiang LU Peng +4 位作者 CHENG Bin KARVONEN Juha WANG Qimao LI Zhijun HAN Hongwei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第3期42-50,共9页
A retrieval algorithm of arctic sea ice concentration (SIC) based on the brightness temperature data of “HY-2” scanning microwave radiometer has been constructed. The tie points of the brightness temperature were ... A retrieval algorithm of arctic sea ice concentration (SIC) based on the brightness temperature data of “HY-2” scanning microwave radiometer has been constructed. The tie points of the brightness temperature were selected based on the statistical analysis of a polarization gradient ratio and a spectral gradient ratio over open water (OW), first-year ice (FYI), and multiyear ice (MYI) in arctic. The thresholds from two weather filters were used to reduce atmospheric effects over the open ocean. SIC retrievals from the “HY-2” radiom-eter data for idealized OW, FYI, and MYI agreed well with theoretical values. The 2012 annual SIC was calcu-lated and compared with two reference operational products from the National Snow and Ice Data Center (NSIDC) and the University of Bremen. The total ice-covered area yielded by the “HY-2” SIC was consistent with the results from the reference products. The assessment of SIC with the aerial photography from the fifth Chinese national arctic research expedition (CHINARE) and six synthetic aperture radar (SAR) images from the National Ice Service was carried out. The “HY-2” SIC product was 16% higher than the values de-rived from the aerial photography in the central arctic. The root-mean-square (RMS) values of SIC between “HY-2” and SAR were comparable with those between the reference products and SAR, varying from 8.57% to 12.34%. The “HY-2” SIC is a promising product that can be used for operational services. 展开更多
关键词 “HY-2” scanning microwave radiometer retrieval algorithm sea ice concentration ARCTIC
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Simultaneous Non-linear Retrieval of Atmospheric Temperature and Absorbing Constituent Profiles from Satellite Infrared Sounder Radiances 被引量:5
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作者 李俊 周风仙 曾庆存 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1994年第2期128-138,共11页
Based on Zeng's theory (1974), a successive linearized form of radiative transfer equation (RTE) is derived for simultaneous retrieval of atmospheric temperature and absorbing constituent profiles from satellite i... Based on Zeng's theory (1974), a successive linearized form of radiative transfer equation (RTE) is derived for simultaneous retrieval of atmospheric temperature and absorbing constituent profiles from satellite infrared observations. It contains the temperature component weighting function and absorbing constituent (HZO, O3, CH4 etc.) component weighting functions. All these weighting functions reach maximum at their own 'optimum information levels', and make the remote sensing equations well-conditional. Then the atmospheric profiles are derived by Newton'snon-linear iteration method. Experiments of retrieval from both TIROS-N operational High Resolution infrared Sounder (HIRS) and the simulated Atmospheric infRared Sounder (AIRS) show an significant improvement. 展开更多
关键词 SOUNDING Weighting Function RETRIEVAL
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First-in-man implantation of the retrievable and repositionable VenusA-Plus valve 被引量:4
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作者 Xian-bao Liu Yu-xin He +10 位作者 Chun-hui Liu Li-han Wang Feng Gao Lei Yu Ai-qiang Dong Min-jian Kong Ji-fang Chen Yong Xu Qi-jing Zhou Min Yan Jian-an Wang 《World Journal of Emergency Medicine》 SCIE CAS 2018年第1期64-66,共3页
BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. ... BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. METHODS: A 76-year-old patient with symptomatic severe aortic stenosis and high surgical risk(STS 13.8%) was recommended for transcatheter aortic valve replacement(TAVR) by heart valve team. Type 0 bicuspid aortic valve with asymmetric calcification was identified by dual source computed tomography, and the unfavorable anatomies increased the possibility of malposition and paravalvular leakage during TAVR. Therefore, we used the retrievable and repositionable Venus APlus valve for the patient.RESULTS: Transfemoral TAVR was performed under local anesthesia with sedation, and a 26-mm VenusA-Plus valve was successfully implanted. No transvalvular pressure gradient and trace paravalvular leakage were found. CONCLUSION: The successful first-in-man implantation indicates the retrievable and repositionable Venus A-Plus valve is feasible in complicated TAVR cases such as bicuspid aortic valve. 展开更多
关键词 Transcatheter aortic valve replacement Venus A-Plus valve retrievable Repositionable Bicuspid aortic valve
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Leaf area index retrieval based on canopy reflectance and vegetation index in eastern China 被引量:5
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作者 JIANGJianjun CHENSuozhong +3 位作者 CAOShunxian WUHongan ZHANGLi ZHANGHailong 《Journal of Geographical Sciences》 SCIE CSCD 2005年第2期247-254,共8页
The aim of this paper is to investigate the feasibility of using Landsat TM data to retrieve leaf area index (LAI). To get a LAI retrieval model based ground reflectance and vegetation index, detailed field data were ... The aim of this paper is to investigate the feasibility of using Landsat TM data to retrieve leaf area index (LAI). To get a LAI retrieval model based ground reflectance and vegetation index, detailed field data were collected in the study area of eastern China, dominated by bamboo, tea plant and greengage. Plant canopy reflectance of Landsat TM wavelength bands has been inversed using software of 6S. LAI is an important ecological parameter. In this paper, atmospheric corrected Landsat TM imagery was utilized to calculate different vegetation indices (VI), such as simple ratio vegetation index (SR), shortwave infrared modified simple ratio (MSR), and normalized difference vegetation index (NDVI). Data of 53 samples of LAI were measured by LAI-2000 (LI-COR) in the study area. LAI was modeled based on different reflectances of bands and different vegetation indices from Landsat TM and LAI samples data. There are certainly correlations between LAI and the reflectance of TM3, TM4, TM5 and TM7. The best model through analyzing the results is LAI = 1.2097*MSR + 0.4741 using the method of regression analysis. The result shows that the correlation coefficient R2 is 0.5157, and average accuracy is 85.75%. However, whether the model of this paper is suitable for application in subtropics needs to be verified in the future. 展开更多
关键词 Landsat TM Leaf area Index (LAI) vegetation indices retrieval model Taihu Lake
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X-RESTORE: Middleware for XML's Relational Storage and Retrieve 被引量:4
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作者 Wan Chang-xuan +1 位作者 Liu Yun-Sheng 《Wuhan University Journal of Natural Sciences》 CAS 2003年第01A期28-34,共7页
We propose a new approach to store and query XML data in an RDBMS basing on the idea of the numbering scheme and inverted list. O ur approach allows us to quickly determine the precedence, sibling and ancestor/ desc... We propose a new approach to store and query XML data in an RDBMS basing on the idea of the numbering scheme and inverted list. O ur approach allows us to quickly determine the precedence, sibling and ancestor/ descendant relationships between any pair of nodes in the hierarchy of XML, and utilize path index to speed up calculating of path expressions. Examples have de monstrated that our approach can effectively and efficiently support both XQuery queries and keyword searches. Our approach is also flexible enough to support X ML documents both with Schema and without Schema, and applications both retrieva l and update. We also present the architecture of middleware for application acc essing XML documents stored in relations, and an algorithm translating a given X ML document into relations effectively. 展开更多
关键词 XML retrieve keyword search relational storage numbering scheme
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A Deep-Learning and Transfer-Learning Hybrid Aerosol Retrieval Algorithm for FY4-AGRI:Development and Verification over Asia
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作者 Disong Fu Hongrong Shi +9 位作者 Christian AGueymard Dazhi Yang Yu Zheng Huizheng Che Xuehua Fan Xinlei Han Lin Gao Jianchun Bian Minzheng Duan Xiangao Xia 《Engineering》 SCIE EI CAS CSCD 2024年第7期164-174,共11页
The Advanced Geosynchronous Radiation Imager(AGRI)is a mission-critical instrument for the Fengyun series of satellites.AGRI acquires full-disk images every 15 min and views East Asia every 5 min through 14 spectral b... The Advanced Geosynchronous Radiation Imager(AGRI)is a mission-critical instrument for the Fengyun series of satellites.AGRI acquires full-disk images every 15 min and views East Asia every 5 min through 14 spectral bands,enabling the detection of highly variable aerosol optical depth(AOD).Quantitative retrieval of AOD has hitherto been challenging,especially over land.In this study,an AOD retrieval algorithm is proposed that combines deep learning and transfer learning.The algorithm uses core concepts from both the Dark Target(DT)and Deep Blue(DB)algorithms to select features for the machinelearning(ML)algorithm,allowing for AOD retrieval at 550 nm over both dark and bright surfaces.The algorithm consists of two steps:①A baseline deep neural network(DNN)with skip connections is developed using 10 min Advanced Himawari Imager(AHI)AODs as the target variable,and②sunphotometer AODs from 89 ground-based stations are used to fine-tune the DNN parameters.Out-of-station validation shows that the retrieved AOD attains high accuracy,characterized by a coefficient of determination(R2)of 0.70,a mean bias error(MBE)of 0.03,and a percentage of data within the expected error(EE)of 70.7%.A sensitivity study reveals that the top-of-atmosphere reflectance at 650 and 470 nm,as well as the surface reflectance at 650 nm,are the two largest sources of uncertainty impacting the retrieval.In a case study of monitoring an extreme aerosol event,the AGRI AOD is found to be able to capture the detailed temporal evolution of the event.This work demonstrates the superiority of the transfer-learning technique in satellite AOD retrievals and the applicability of the retrieved AGRI AOD in monitoring extreme pollution events. 展开更多
关键词 Aerosol optical depth Retrieval algorithm Deep learning Transfer learning Advanced Geosynchronous Radiation IMAGER
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Quantifying the chemical composition of weathering products of Hainan basalts with reflectance spectroscopy and its implications for Mars
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作者 Xing Wu JiaCheng Liu +5 位作者 WeiChao Sun Yang Liu Joseph Michalski Wei Tan XiaoRong Qin YongLiao Zou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期854-867,共14页
With the development of the hyperspectral remote sensing technique,extensive chemical weathering profiles have been identified on Mars.These weathering sequences,formed through precipitation-driven leaching processes,... With the development of the hyperspectral remote sensing technique,extensive chemical weathering profiles have been identified on Mars.These weathering sequences,formed through precipitation-driven leaching processes,can reflect the paleoenvironments and paleoclimates during pedogenic processes.The specific composition and stratigraphic profiles mirror the mineralogical and chemical trends observed in weathered basalts on Hainan Island in south China.In this study,we investigated the laboratory reflectance spectra of a 53-m-long drilling core of a thick basaltic weathering profile collected from Hainan Island.We established a quantitative spectral model by combining the genetic algorithm and partial least squares regression(GA-PLSR)to predict the chemical properties(SiO2,Al2O3,Fe2O3)and index of laterization(IOL).The entire sample set was divided into a calibration set of 25 samples and a validation set of 12 samples.Specifically,the GA was used to select the spectral subsets for each composition,which were then input into the PLSR model to derive the chemical concentration.The coefficient of determination(R2)values on the validation set for SiO2,Al2O3,Fe2O3,and the IOL were greater than 0.9.In addition,the effects of various spectral preprocessing techniques on the model accuracy were evaluated.We found that the spectral derivative treatment boosted the prediction accuracy of the GA-PLSR model.The improvement achieved with the second derivative was more pronounced than when using the first derivative.The quantitative model developed in this work has the potential to estimate the contents of similar weathering basalt products,and thus infer the degree of alteration and provide insights into paleoclimatic conditions.Moreover,the informative bands selected by the GA can serve as a guideline for designing spectral channels for the next generation of spectrometers. 展开更多
关键词 reflectance spectroscopy weathered basalts terrestrial analog quantitative retrieval MARS
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Efficiency-Driven Custom Chatbot Development: Unleashing LangChain, RAG, and Performance-Optimized LLM Fusion
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作者 S.Vidivelli Manikandan Ramachandran A.Dharunbalaji 《Computers, Materials & Continua》 SCIE EI 2024年第8期2423-2442,共20页
This exploration acquaints a momentous methodology with custom chatbot improvement that focuses on pro-ficiency close by viability.We accomplish this by joining three key innovations:LangChain,Retrieval Augmented Gene... This exploration acquaints a momentous methodology with custom chatbot improvement that focuses on pro-ficiency close by viability.We accomplish this by joining three key innovations:LangChain,Retrieval Augmented Generation(RAG),and enormous language models(LLMs)tweaked with execution proficient strategies like LoRA and QLoRA.LangChain takes into consideration fastidious fitting of chatbots to explicit purposes,guaranteeing engaged and important collaborations with clients.RAG’s web scratching capacities engage these chatbots to get to a tremendous store of data,empowering them to give exhaustive and enlightening reactions to requests.This recovered data is then decisively woven into reaction age utilizing LLMs that have been calibrated with an emphasis on execution productivity.This combination approach offers a triple advantage:further developed viability,upgraded client experience,and extended admittance to data.Chatbots become proficient at taking care of client questions precisely and productively,while instructive and logically pertinent reactions make a more regular and drawing in cooperation for clients.At last,web scratching enables chatbots to address a more extensive assortment of requests by conceding them admittance to a more extensive information base.By digging into the complexities of execution proficient LLM calibrating and underlining the basic job of web-scratched information,this examination offers a critical commitment to propelling custom chatbot plan and execution.The subsequent chatbots feature the monstrous capability of these advancements in making enlightening,easy to understand,and effective conversational specialists,eventually changing the manner in which clients cooperate with chatbots. 展开更多
关键词 LangChain retrieval augumental generation(RAG) fine tuning
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Precise Three-Dimensional Deformation Retrieval in Large and Complex Deformation Areas via Integration of Offset-Based Unwrapping and Improved Multiple-Aperture SAR Interferometry:Application to the 2016 Kumamoto Earthquake 被引量:5
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作者 Won-Kyung Baek Hyung-Sup Jung 《Engineering》 SCIE EI 2020年第8期927-935,共9页
Conventional synthetic aperture radar(SAR)interferometry(InSAR)has been successfully used to precisely measure surface deformation in the line-of-sight(LOS)direction,while multiple-aperture SAR interferometry(MAI)has ... Conventional synthetic aperture radar(SAR)interferometry(InSAR)has been successfully used to precisely measure surface deformation in the line-of-sight(LOS)direction,while multiple-aperture SAR interferometry(MAI)has provided precise surface deformation in the along-track(AT)direction.Integration of the InSAR and MAI methods enables precise measurement of the two-dimensional(2D)deformation from an interferometric pair;recently,the integration of ascending and descending pairs has allowed the observation of precise three-dimensional(3D)deformation.Precise 3D deformation measurement has been applied to better understand geological events such as earthquakes and volcanic eruptions.The surface deformation related to the 2016 Kumamoto earthquake was large and complex near the fault line;hence,precise 3D deformation retrieval had not yet been attempted.The objectives of this study were to①perform a feasibility test of precise 3D deformation retrieval in large and complex deformation areas through the integration of offset-based unwrapped and improved multiple-aperture SAR interferograms and②observe the 3D deformation field related to the 2016 Kumamoto earthquake,even near the fault lines.Two ascending pairs and one descending the Advanced Land Observing Satellite-2(ALOS-2)Phased Array-type L-band Synthetic Aperture Radar-2(PALSAR-2)pair were used for the 3D deformation retrieval.Eleven in situ Global Positioning System(GPS)measurements were used to validate the 3D deformation measurement accuracy.The achieved accuracy was approximately 2.96,3.75,and 2.86 cm in the east,north,and up directions,respectively.The results show the feasibility of precise 3D deformation measured through the integration of the improved methods,even in a case of large and complex deformation. 展开更多
关键词 Synthetic aperture radar(SAR) Conventional SAR interferometry(InSAR) Multiple-aperture SAR interferometry(MAI) ALOS-2 PALSAR-2 3D deformation retrieval 2016 Kumamoto earthquake
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Precipitation Retrieval from Himawari-8 Satellite Infrared Data Based on Dictionary Learning Method and Regular Term Constraint 被引量:2
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作者 Wang Gen Ding Conghui Liu Huilan 《Meteorological and Environmental Research》 CAS 2019年第3期61-65,68,共6页
In this paper,the application of an algorithm for precipitation retrieval based on Himawari-8 (H8) satellite infrared data is studied.Based on GPM precipitation data and H8 Infrared spectrum channel brightness tempera... In this paper,the application of an algorithm for precipitation retrieval based on Himawari-8 (H8) satellite infrared data is studied.Based on GPM precipitation data and H8 Infrared spectrum channel brightness temperature data,corresponding "precipitation field dictionary" and "channel brightness temperature dictionary" are formed.The retrieval of precipitation field based on brightness temperature data is studied through the classification rule of k-nearest neighbor domain (KNN) and regularization constraint.Firstly,the corresponding "dictionary" is constructed according to the training sample database of the matched GPM precipitation data and H8 brightness temperature data.Secondly,according to the fact that precipitation characteristics in small organizations in different storm environments are often repeated,KNN is used to identify the spectral brightness temperature signal of "precipitation" and "non-precipitation" based on "the dictionary".Finally,the precipitation field retrieval is carried out in the precipitation signal "subspace" based on the regular term constraint method.In the process of retrieval,the contribution rate of brightness temperature retrieval of different channels was determined by Bayesian model averaging (BMA) model.The preliminary experimental results based on the "quantitative" evaluation indexes show that the precipitation of H8 retrieval has a good correlation with the GPM truth value,with a small error and similar structure. 展开更多
关键词 Himawari-8(H8) RETRIEVAL of PRECIPITATION k-nearest NEIGHBOR (KNN) REGULAR TERM constraints DICTIONARY method Bayesian model average (BMA)
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A Neural Network Based Single Footprint Temperature Retrieval for Atmospheric Infrared Sounder Measurements and Its Application to Study on Stratospheric Gravity Wave 被引量:1
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作者 YAO Zhi-gang HONG Jun +2 位作者 CUI Xing-dong ZHAO Zeng-liang HAN Zhi-gang 《Journal of Tropical Meteorology》 SCIE 2022年第1期82-94,共13页
Satellite hyperspectral infrared sounder measurements have better horizontal resolution than other sounding techniques as it boasts the stratospheric gravity wave(GW)analysis.To accurately and efficiently derive the t... Satellite hyperspectral infrared sounder measurements have better horizontal resolution than other sounding techniques as it boasts the stratospheric gravity wave(GW)analysis.To accurately and efficiently derive the three-dimensional structure of the stratospheric GWs from the single-field-of-view(SFOV)Atmospheric Infra Red Sounder(AIRS)observations,this paper firstly focuses on the retrieval of the atmospheric temperature profiles in the altitude range of 20-60 km with an artificial neural network approach(ANN).The simulation experiments show that the retrieval bias is less than 0.5 K,and the root mean square error(RMSE)ranges from 1.8 to 4 K.Moreover,the retrieval results from 20 granules of the AIRS observations with the trained neural network(AIRS_SFOV)and the corresponding operational AIRS products(AIRS_L2)as well as the dual-regression results from the Cooperative Institute for Meteorological Satellite Studies(CIMSS)(AIRS_DR)are compared respectively with ECMWF T799 data.The comparison indicates that the standard deviation of the ANN retrieval errors is significantly less than that of the AIRS_DR.Furthermore,the analysis of the typical GW events induced by the mountain Andes and the typhoon"Soulik"using different data indicates that the AIRS_SFOV results capture more details of the stratospheric gravity waves in the perturbation amplitude and pattern than the operational AIRS products do. 展开更多
关键词 STRATOSPHERE gravity wave temperature retrieval hyperspectral infrared sounder
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The Study of In-Orbit Calibration Accuracy of NOAA Satellite Infrared Sounder and Its Effect on Temperature Profile Retrievals 被引量:1
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作者 董超华 刘全华 +1 位作者 黎光清 张凤英 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第2期211-219,共9页
The calibration accuracy of High Resolution Infrared Radiation Sounder Mod. 2 (HIRS / 2) on NOAA-10 satellite is analyzed in this paper. The non-linear effect in the linear calibration curve induces a deviation of 1.5... The calibration accuracy of High Resolution Infrared Radiation Sounder Mod. 2 (HIRS / 2) on NOAA-10 satellite is analyzed in this paper. The non-linear effect in the linear calibration curve induces a deviation of 1.5 degrees (k) of brightness temperature in the tenth channel (8.3 um, water vapor absorption) of the HIRS/2 and the non-linear effect affects the other channels to a different extent. Based on analyzing non- linearity in two-point calibration curve, a tri-point calibration equation is given. A numerical test of effects of the linear and non-linear calibration models on the accuracy of atmospheric temperature retrievals is carried out. 展开更多
关键词 In The Study of In-Orbit Calibration Accuracy of NOAA Satellite Infrared Sounder and Its Effect on Temperature Profile Retrievals NOAA CLI
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NeuPh:scalable and generalizable neural phase retrieval with local conditional neural fields
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作者 Hao Wang Jiabei Zhu +2 位作者 Yunzhe Li Qianwan Yang Lei Tian 《Advanced Photonics Nexus》 2024年第5期67-76,共10页
Deep learning has transformed computational imaging,but traditional pixel-based representations limit their ability to capture continuous multiscale object features.Addressing this gap,we introduce a local conditional... Deep learning has transformed computational imaging,but traditional pixel-based representations limit their ability to capture continuous multiscale object features.Addressing this gap,we introduce a local conditional neural field(LCNF)framework,which leverages a continuous neural representation to provide flexible object representations.LCNF’s unique capabilities are demonstrated in solving the highly ill-posed phase retrieval problem of multiplexed Fourier ptychographic microscopy.Our network,termed neural phase retrieval(NeuPh),enables continuous-domain resolution-enhanced phase reconstruction,offering scalability,robustness,accuracy,and generalizability that outperform existing methods.NeuPh integrates a local conditional neural representation and a coordinate-based training strategy.We show that NeuPh can accurately reconstruct high-resolution phase images from low-resolution intensity measurements.Furthermore,NeuPh consistently applies continuous object priors and effectively eliminates various phase artifacts,demonstrating robustness even when trained on imperfect datasets.Moreover,NeuPh improves accuracy and generalization compared with existing deep learning models.We further investigate a hybrid training strategy combining both experimental and simulated datasets,elucidating the impact of domain shift between experiment and simulation.Our work underscores the potential of the LCNF framework in solving complex large-scale inverse problems,opening up new possibilities for deep-learning-based imaging techniques. 展开更多
关键词 neural representation phase retrieval computational imaging deep learning computational microscopy
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Atmospheric CO_2 retrieval with a look-up-table based method by combining near and thermal infrared spectra
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作者 吴军 方勇华 +2 位作者 王先华 叶函函 江新华 《Journal of Beijing Institute of Technology》 EI CAS 2014年第4期557-565,共9页
In order to precisely retrieve the atmospheric CO2 , a retrieval method based on both near infrared (NIR) and thermal infrared (TIR) is established firstly. Then a look-up-table (LUT) based fast line-by-line rad... In order to precisely retrieve the atmospheric CO2 , a retrieval method based on both near infrared (NIR) and thermal infrared (TIR) is established firstly. Then a look-up-table (LUT) based fast line-by-line radiative transfer model (RTM) was integrated into the retrieval procedure to accelerate radiative transfer calculations. The LUT stores gas absorption cross-sections as a function of temperature, pressure and wavenumber. It could greatly reduce calculating time in radiative transfer compared to direct line-by-line method. Then retrieval was simulated using NIR, TIR and both bands. The retrieved CO2 profiles suggest joint approach could reconstruct CO2 profile better than those using NIR or TIR alone. Joint retrieval using both bands simultaneously could provide better constrain to CO2 vertical distribution in the whole troposphere. 展开更多
关键词 RETRIEVAL high resolution IR spectra look-up-table (LUT) atmospheric CO2
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The Complete K-Level Tree and Its Application to Data Warehouse Filtering
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作者 马琳 Wang Kuanquan +1 位作者 Li Haifeng Zucker J D 《High Technology Letters》 EI CAS 2003年第4期13-16,共4页
This paper presents a simple complete K level tree (CKT) architecture for text database organization and rapid data filtering. A database is constructed as a CKT forest and each CKT contains data of the same length. T... This paper presents a simple complete K level tree (CKT) architecture for text database organization and rapid data filtering. A database is constructed as a CKT forest and each CKT contains data of the same length. The maximum depth and the minimum depth of an individual CKT are equal and identical to data’s length. Insertion and deletion operations are defined; storage method and filtering algorithm are also designed for good compensation between efficiency and complexity. Applications to computer aided teaching of Chinese and protein selection show that an about 30% reduction of storage consumption and an over 60% reduction of computation may be easily obtained. 展开更多
关键词 complete K level tree data warehouse organization data filtering data retrieval
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Opportunities for Remote Collaboration in a Social Web Search Model That Integrates Parents and Children
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作者 Sandra Regina Rocha Silva Geraldo Bonorino Xexéo Moacir Florentino da Silva Jr. 《Social Networking》 2014年第2期127-133,共7页
Traditionally, search engines are designed to support a single user working alone. However, the construction of knowledge is enriched when one adds collaboration to search tasks. We identified opportunities for remote... Traditionally, search engines are designed to support a single user working alone. However, the construction of knowledge is enriched when one adds collaboration to search tasks. We identified opportunities for remote collaboration in a Social Web search model that integrates parents and children guided by 5W + 1H (who, what, where, when, why, how) dimensions. Our social search model aims at improving the search process for children. We found 7 opportunities for remote collaboration on the search process, based on implicit-explicit interactions. 展开更多
关键词 Social Search COLLABORATIVE INFORMATION Retrieval COLLABORATIVE INFORMATION SEEKING OPPORTUNITIES for Collaboration CHILD
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A Survey of Community Pharmacists about Work-Related Issues, How they Solve them, and who they Consult with to Solve them: Comparison of Results from the Hokkaido Area vs. a Nationwide Survey
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作者 Sumiyo Umeda Hitomi Yanaguimoto +1 位作者 Seiichi Furuta Nahoko Kurosawa 《Pharmacology & Pharmacy》 2018年第10期447-456,共10页
We surveyed the drug information retrieval practices among community pharmacists in more rural Hokkaido and in entire Japan in order to explore local characteristics of work-related issues, how community pharmacists a... We surveyed the drug information retrieval practices among community pharmacists in more rural Hokkaido and in entire Japan in order to explore local characteristics of work-related issues, how community pharmacists access information to address such issues, and with whom they consult to solve them. Based on the findings, we propose a strategy for improvements in similar support systems. The percentage of respondents who had experience with home care services was significantly lower in the Hokkaido group (56.0% of 207) than in the nationwide group (70.0% of 250), as was the percentage of respondents who consulted the pharmacist association and branch board (13.0% and 20.4%, respectively). The Hokkaido group also made significantly less use of websites such as d.m3.com and e.CareNet.com. The results of this survey thus indicate that the drug information retrieval in the Hokkaido group had a low implementation rate of home care services. In addition, there were low levels of utilization of the local pharmacist association, and low utilization of the websites d.m3.com and e.CareNet.com. To enhance the Hokkaido community-based integrated care system (and ones like it), we propose that it is necessary to: 1) support activities of local pharmacist associations, and 2) promote proactive implementation of drug information retrieval through education. 展开更多
关键词 DRUG Informatics Pharmacy DRUG Information Retrieval HOKKAIDO Japan
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