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News Modeling and Retrieving Information: Data-Driven Approach
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作者 Elias Hossain Abdullah Alshahrani Wahidur Rahman 《Intelligent Automation & Soft Computing》 2023年第11期109-123,共15页
This paper aims to develop Machine Learning algorithms to classify electronic articles related to this phenomenon by retrieving information and topic modelling.The Methodology of this study is categorized into three p... This paper aims to develop Machine Learning algorithms to classify electronic articles related to this phenomenon by retrieving information and topic modelling.The Methodology of this study is categorized into three phases:the Text Classification Approach(TCA),the Proposed Algorithms Interpretation(PAI),andfinally,Information Retrieval Approach(IRA).The TCA reflects the text preprocessing pipeline called a clean corpus.The Global Vec-tors for Word Representation(Glove)pre-trained model,FastText,Term Frequency-Inverse Document Fre-quency(TF-IDF),and Bag-of-Words(BOW)for extracting the features have been interpreted in this research.The PAI manifests the Bidirectional Long Short-Term Memory(Bi-LSTM)and Convolutional Neural Network(CNN)to classify the COVID-19 news.Again,the IRA explains the mathematical interpretation of Latent Dirich-let Allocation(LDA),obtained for modelling the topic of Information Retrieval(IR).In this study,99%accuracy was obtained by performing K-fold cross-validation on Bi-LSTM with Glove.A comparative analysis between Deep Learning and Machine Learning based on feature extraction and computational complexity exploration has been performed in this research.Furthermore,some text analyses and the most influential aspects of each document have been explored in this study.We have utilized Bidirectional Encoder Representations from Trans-formers(BERT)as a Deep Learning mechanism in our model training,but the result has not been uncovered satisfactory.However,the proposed system can be adjustable in the real-time news classification of COVID-19. 展开更多
关键词 COVID-19 news retrieving DATA-DRIVEN machine learning BERT topic modelling
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Theoretical Analysis of Retrieving Atmospheric Columnar Mie Optical Depth from Downward Total Solar Radiative Flux 被引量:1
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作者 邱金桓 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第3期313-323,共11页
In this paper, the principle to determine the atmospheric columnar Mie optical depth from downward total solar radiative flux is theoretically studied, and the effect on Mie optical depth solution of the errors in sur... In this paper, the principle to determine the atmospheric columnar Mie optical depth from downward total solar radiative flux is theoretically studied, and the effect on Mie optical depth solution of the errors in surface albedo, sin-gle scattering albedo, asymmetrical factor of scattering phase function, instrumental constant and the approximate expression of diffusion flux is analy/ed, and then a method for determining surface albedo in shorter wavelength range is presented. 展开更多
关键词 Theoretical Analysis of retrieving Atmospheric Columnar Mie Optical Depth from Downward Total Solar Radiative Flux
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An Improved Method of Retrieving Sea Surface Wind Speed Based on a Four-Layer Medium Model at High Sea States
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作者 Jiasheng Tian Qiaoyun Liu +1 位作者 Wan Pan Jian Shi 《International Journal of Geosciences》 2014年第1期85-92,共8页
Considering about the effect of whitecaps and foams on pulse-limited Radar Altimeters, an improved algorithm of retrieving sea surface wind speed is proposed in this paper. Firstly, a four-layer dielectric model is es... Considering about the effect of whitecaps and foams on pulse-limited Radar Altimeters, an improved algorithm of retrieving sea surface wind speed is proposed in this paper. Firstly, a four-layer dielectric model is established in order to simulate an air-sea interface. Secondly, the microwave reflectivity of a sea surface covered by spray droplets and foams at 13.5 GHz is computed based on the established model. These computed results show that the effect of spray droplets and foams in high sea state conditions shall not be negligible on retrieving sea surface wind speed. Finally, compared with the analytical algorithms proposed by Zhao and some calculated results based on a three-layer dielectric model, an improved algorithm of retrieving sea surface wind speed is presented. At a high wind speed, the improved algorithm is in a better accord with some empirical algorithms such as Brown, Young ones and et al., and also in a good agreement with ZT and other algorithms at low wind speed. This new improved algorithm will be suitable not only for low wind speed retrieval, but also for high wind speed retrieval. Better accuracy and effectiveness of wind speed retrieval can also be obtained. 展开更多
关键词 Satellite ALTIMETER Wind Speed retrieving Algorithm HIGH SEA STATES STRATIFIED Media Whitecap COVERAGE Rate
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Retrieving Atmospheric Temperature Profiles from AMSU-A Data with Neural Networks 被引量:15
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作者 姚志刚 陈洪滨 林龙福 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第4期606-616,共11页
Back propagation neural networks are used to retrieve atmospheric temperature profiles from NOAA-16 Advanced Microwave Sounding Unit-A (AMSU-A) measurements over East Asia. The collocated radiosonde observation and AM... Back propagation neural networks are used to retrieve atmospheric temperature profiles from NOAA-16 Advanced Microwave Sounding Unit-A (AMSU-A) measurements over East Asia. The collocated radiosonde observation and AMSU-A data over land in 2002-2003 are used to train the network, and the data over land in 2004 are used to test the network. A comparison with the multi-linear regression method shows that the neural network retrieval method can significantly improve the results in all weather conditions. When an offset of 0.5 K or a noise level of ±0.2 K is added to all channels simultaneously, the increase in the overall root mean square (RMS) error is less than 0.1 K. Furthermore, an experiment is conducted to investigate the effects of the window channels on the retrieval. The results indicate that the brightness temperatures of window channels can provide significantly useful information on the temperature retrieval near the surface. Additionally, the RMS errors of the profiles retrieved with the trained neural network are compared with the errors from the International Advanced TOVS (ATOVS) Processing Package (IAPP). It is shown that the network-based algorithm can provide much better results in the experiment region and comparable results in other regions. It is also noted that the network can yield remarkably better results than IAPP at the low levels and at about the 250-hPa level in summer skies over ocean. Finally, the network-based retrieval algorithm developed herein is applied in retrieving the temperature anomalies of Typhoon Rananim from AMSU-A data. 展开更多
关键词 AMSU-A neural network temperature profiles RETRIEVAL
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A new algorithm of retrieving a petroleum substances absorption coefficient in sea water based on a remote sensing image 被引量:7
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作者 HUANG Miaofen XING Xufeng +2 位作者 SONG Qingjun LIU Yang DONG Wentong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第11期97-104,共8页
Establishing the remote sensing algorithm of retrieving the absorption coefficient of seawater petroleum substances is an efficient way to improve the accuracy of retrieving a seawater petroleum concentration using a ... Establishing the remote sensing algorithm of retrieving the absorption coefficient of seawater petroleum substances is an efficient way to improve the accuracy of retrieving a seawater petroleum concentration using a remote sensing technology. A remote sensing reflectance is a basic physical parameter in water color remote sensing. Apply it to directly retrieve the absorption coefficient of seawater petroleum substances is of potential advantage. The absorption coefficient of waters containing petroleum [ACWCP, a_o(λ)], consists of the absorption coefficient of pure water [ACPW, a_w(λ)], plankton [ACP, a_(ph)(λ)], colored scraps [ACCS, a_(d,g)(λ)], and petroleum substance [ACPS, a_(oil)(λ)]. Among those, ACCS consists of the absorption coefficient of nonalgal particle [ACNP, a_d(λ)] and colored dissolved organic matter [ACCDOM, a_g(λ)]. For waters containing petroleum, the retrieved ACCS using the existing method is a combination absorption coefficient of ACNP,ACCDOM and ACPA [CAC, a_(d,g,oil)(λ)]. Therefore, the principle question is how to extract ACPS from CAC.Through the analysis of the three proportion tests conducted between the year of 2013 and 2015 and the corresponding remote sensing data, an algorithm of retrieving the absorption coefficient of petroleum substances is proposed based on remote sensing reflectance. First of all, ACPS and CAC are retrieved from the reflectance using the quasi-analytical algorithm(QAA), with some parameter modified. Secondly, given the fact that the backscatter coefficient [BC, b_(bp)(555)] of total particles at 555 nm can be obtained completely from the reflectance, the relation between BC and ACNP in petroleum contaminated water can be established. As a result, ACNP can be calculated. Then, combining the remote sensing retrieving algorithm of a_g(440), the method of achieving the spectral slope of the absorption coefficient can be established, from which ACCDOM,can be calculated. Finally, ACPS can be computed as the residual. The accuracy of ACPS based on this algorithm is 86% compared with the in situ measurements. 展开更多
关键词 petroleum substances in sea water remote sensing technology absorption coefficient retrieval algorithm
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Retrieving Soil Water Contents from Soil Temperature Measurements by Using Linear Regression 被引量:1
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作者 Qin XU Binbin ZHOU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第6期849-858,共10页
A simple linear regression method is developed to retrieve daily averaged soil water content from diurnal variations of soil temperature measured at three or more depths. The method is applied to Oklahoma Mesonet soil... A simple linear regression method is developed to retrieve daily averaged soil water content from diurnal variations of soil temperature measured at three or more depths. The method is applied to Oklahoma Mesonet soil temperature data collected at the depths of 5, 10, and 30 cm during 11–20 June 1995. The retrieved bulk soil water contents are compared with direct measurements for one pair of nearly collocated Mesonet and ARM stations and also compared with the retrievals of a previous method at 14 enhanced Oklahoma Mesonet stations. The results show that the current method gives more persistent retrievals than the previous method. The method is also applied to Oklahoma Mesonet soil temperature data collected at the depths of 5, 25, 60, and 75 cm from the Norman site during 20–30 July 1998 and 1–31 July 2000. The retrieved soil water contents are verified by collocated soil water content measurements with rms differences smaller than the soil water observation error (0.05 m<SUP>3</SUP> m<SUP>&#8722;3</SUP>). The retrievals are found to be moderately sensitive to random errors (±0.1 K) in the soil temperature observations and errors in the soil type specifications. 展开更多
关键词 RETRIEVAL soil water content
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Feasibility of a novel beamforming algorithm via retrieving spatial harmonics 被引量:1
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作者 NOROLAHI Jafar AZMI Paeiz NASIRIAN Mahdi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第1期38-46,共9页
This paper introduces an algorithm for beamforming systems by the aid of multidimensional harmonic retrieval(MHR).This algorithm resolves problems,removes limitations of sampling and provides a more robust beamformer.... This paper introduces an algorithm for beamforming systems by the aid of multidimensional harmonic retrieval(MHR).This algorithm resolves problems,removes limitations of sampling and provides a more robust beamformer.A new sample space is created that can be used for estimating weights of a new beamforming called spatial-harmonics retrieval beamformer(SHRB).Simulation results show that SHRB has a better performance,accuracy,and applicability and more powerful eigenvalues than conventional beamformers.A simple mathematical proof is provided.By changing the number of harmonics,as a degree of freedom that is missing in conventional beamformers,SHRB can achieve more optimal outputs without increasing the number of spatial or temporal samples.We will demonstrate that SHRB offers an improvement of 4 dB in signal to noise ratio(SNR) in bit error rate(BER) of 10~(-4) over conventional beamformers.In the case of direction of arrival(DOA) estimation,SHRB can estimate the DOA of the desired signal with an SNR of-25 dB,when conventional methods cannot have acceptable response. 展开更多
关键词 multi-input-multi-output(MIMO) BEAMFORMING spatial and temporal signal processing multidimensional harmonic retrieval(MHR) space-time signal processing array signal processing
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Matching Strategies and Fuzzy URLs in Web Based Component Retrieving
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作者 Wang Ying 1,2 , Sang Da yong 2, 3 1. College of Management, Xi’an Jiaotong University, Xi’an 710049,China 2.College of Engineering, Air Force University of Engineering, Xi’an 710038,China 3. State Key Laboratory of Software Engineering, Wu 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期283-287,共5页
The World Wide Web (WWW) has greatly changed the way of component based software reuse, for large number of components provided by different vendors become available and it's rather difficult to find and choose w... The World Wide Web (WWW) has greatly changed the way of component based software reuse, for large number of components provided by different vendors become available and it's rather difficult to find and choose what we in fact need. To make large amount of the components collaborate, an information exchanging model is essential. In order to retrieve and search the suitable or usable components more effectively, some techniques should be taken into account. Among these techniques, matching strategies and fuzzy URL semantics are significant for the former help us to find components which could be reused and the other both to broaden the searching areas and use some uncertain information to make the searching more purposive. A brief discuss on an abstract component model (UACModel) is begun, which was proposed to promote the interoperability and information exchange among various reusable component libraries (RCLs), and a framework for component retrieval. Then the emphases are put on some matching strategies, especially incomplete ones that encourage reuse through component customization, and fuzzy URL extensions to be supported and realized. 展开更多
关键词 component reuse interoperability model component retrieval index repository reusable component library (RCL)
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Precipitation Detection and Retrieving Based on FY-3C MWHTS
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作者 HE Jieying 《遥感科学(中英文版)》 2017年第1期1-12,共12页
The paper develops a passive sub-millimeter precipitation retrievals algorithm for Microwave Humidity and Temperature Sounder(MWHTS)onboard the Chinese Feng Yun 3C(FY-3C)satellite.The retrieval algorithm employs a num... The paper develops a passive sub-millimeter precipitation retrievals algorithm for Microwave Humidity and Temperature Sounder(MWHTS)onboard the Chinese Feng Yun 3C(FY-3C)satellite.The retrieval algorithm employs a number of neural network estimators trained and evaluated using the validated global reference physical model NCEP/WRF/ARTS,and works for seawater.NCEP data per 6 hours are downloaded to run the Weather Research and Forecast model WRF,and derive the typical precipitation data from the whole world.The Atmospheric Radiative Transfer Simulator ARTS is feasible for performing simulations of atmospheric radiative transfer.Rain detection algorithm has been used to generate level 2 products.Retrievals are reliable for surface precipitation rate higher than 0.1 mm/h at 15km resolution,which is in good agreement with those retrieved using the Precipitation retrieval algorithm version 1(ATMP-1)for Advanced Technology Microwave Sounder(ATMS)aboard Suomi NPP satellite. 展开更多
关键词 Microwave Humidity Temperature Sounder(MWHTS) Feng Yun(FY-3C)Satellite Precipitation RETRIEVALS Algorithm NCEP/WRF/ARTS
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Seismic ahead-prospecting based on deep learning of retrieving seismic wavefield
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作者 Lei Chen Senlin Yang +5 位作者 Lei Guo Panlong Zhang Kai Li Wei Shao Xinji Xu ⇑Fahe Sun 《Underground Space》 SCIE EI CSCD 2023年第4期262-274,共13页
Unknown geology ahead of the tunnel boring machine(TBM)brings a large safety risk for tunnel construction.Seismic ahead-prospecting using TBM drilling noise as a source can achieve near-real-time detection,meeting the... Unknown geology ahead of the tunnel boring machine(TBM)brings a large safety risk for tunnel construction.Seismic ahead-prospecting using TBM drilling noise as a source can achieve near-real-time detection,meeting the requirements of TBM rapid drilling.Seismic wavefield retrieval is the key data processing step for the efficient utilization of TBM drilling noise.The traditional solution is based on cross-correlation to extract reflected waves,but the reference waves remain in the result,disturbing the imaging and interpre-tation of the adverse geology.To solve this problem,the deep learning method was introduced in wavefield retrieval to improve the accu-racy of geological prospecting.We trained a deep neural network(DNN)with its strong nonlinear mapping capability to transform seismic data from TBM drilling noise to data from the active source.The issue lies in its features for this specific tunnel task,including the decay of the seismic signal with time and the incomplete spatial correspondence.Thus,we improved a classical DNN with the time constraint as an additional input,and an additional pre-decoder to enlarge the receptive field.Additionally,a loss function weighted by the ground truth and time constraint is improved to achieve an accurate retrieval of the effective signal,considering the little effective information in tunnel data.Finally,the workflow of the proposed method was given,and a dataset designed with reference to the field case was employed to train the network.The proposed method accurately retrieved the reflection signal with higher dominant frequen-cies,which helped improve the accuracy of imaging.Numerical simulations and imaging on typical geological models show that the pro-posed method can suppress reference waves and get more accurate results with fewer artifacts.The proposed method has been applied in the Gaoligongshan Tunnel and imaged two abnormal zones,providing meaningful geological information for TBM drilling and tunnel construction. 展开更多
关键词 Tunnel boring machine Seismic ahead-prospecting retrieving wavefield Deep learning Field application
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Retrieving dry snow density with SIR-C polarimetric SAR data 被引量:3
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作者 Zhen Li Huadong Guo Jiancheng Shi 《Chinese Science Bulletin》 SCIE EI CAS 2001年第14期1211-1214,共4页
For a given incidence angle at the snow surface, a greater snow density causes a greater change in the incidence angle at the snow-ground interface; for a given snow density, however, a larger incidence angle at the s... For a given incidence angle at the snow surface, a greater snow density causes a greater change in the incidence angle at the snow-ground interface; for a given snow density, however, a larger incidence angle at the snow surface results in a greater change in the refractive angle in the snow layer, by comparing the difference of incidence angle at the snow-ground interface and the air-snow interface with different snow density. Algorithm for estimating dry snow density used backscattering measurements with polarimetric SAR at L-band frequency is developed based on simulation of the surface backscattering components ghh,and gvv using the IEM model and regression analysis. The comparison of the estimated snow density from SAR L-band images with that from field measurements during the SIR-C/X-SAR overpass shows root means square error of 0.050 g/cm3. It shows that this algorithm can be accurately used to estimate dry snow density distribution. 展开更多
关键词 polarimetric SAR DIELECTRIC CONSTANT BACKSCATTERING DRY SNOW DENSITY retrieving.
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Construction of apricot variety search engine based on deep learning
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作者 Chen Chen Lin Wang +8 位作者 Huimin Liu Jing Liu Wanyu Xu Mengzhen Huang Ningning Gou Chu Wang Haikun Bai Gengjie Jia Tana Wuyun 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期387-397,共11页
Apricot has a long history of cultivation and has many varieties and types. The traditional variety identification methods are timeconsuming and labor-consuming, posing grand challenges to apricot resource management.... Apricot has a long history of cultivation and has many varieties and types. The traditional variety identification methods are timeconsuming and labor-consuming, posing grand challenges to apricot resource management. Tool development in this regard will help researchers quickly identify variety information. This study photographed apricot fruits outdoors and indoors and constructed a dataset that can precisely classify the fruits using a U-net model (F-score:99%), which helps to obtain the fruit's size, shape, and color features. Meanwhile, a variety search engine was constructed, which can search and identify variety from the database according to the above features. Besides, a mobile and web application (ApricotView) was developed, and the construction mode can be also applied to other varieties of fruit trees.Additionally, we have collected four difficult-to-identify seed datasets and used the VGG16 model for training, with an accuracy of 97%, which provided an important basis for ApricotView. To address the difficulties in data collection bottlenecking apricot phenomics research, we developed the first apricot database platform of its kind (ApricotDIAP, http://apricotdiap.com/) to accumulate, manage, and publicize scientific data of apricot. 展开更多
关键词 APRICOT VARIETY Convolutional neural network Deep learning Database platform Mobile application Image retrieval
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A Weighted Multi-Layer Analytics Based Model for Emoji Recommendation
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作者 Amira M.Idrees Abdul Lateef Marzouq Al-Solami 《Computers, Materials & Continua》 SCIE EI 2024年第1期1115-1133,共19页
The developed system for eye and face detection using Convolutional Neural Networks(CNN)models,followed by eye classification and voice-based assistance,has shown promising potential in enhancing accessibility for ind... The developed system for eye and face detection using Convolutional Neural Networks(CNN)models,followed by eye classification and voice-based assistance,has shown promising potential in enhancing accessibility for individuals with visual impairments.The modular approach implemented in this research allows for a seamless flow of information and assistance between the different components of the system.This research significantly contributes to the field of accessibility technology by integrating computer vision,natural language processing,and voice technologies.By leveraging these advancements,the developed system offers a practical and efficient solution for assisting blind individuals.The modular design ensures flexibility,scalability,and ease of integration with existing assistive technologies.However,it is important to acknowledge that further research and improvements are necessary to enhance the system’s accuracy and usability.Fine-tuning the CNN models and expanding the training dataset can improve eye and face detection as well as eye classification capabilities.Additionally,incorporating real-time responses through sophisticated natural language understanding techniques and expanding the knowledge base of ChatGPT can enhance the system’s ability to provide comprehensive and accurate responses.Overall,this research paves the way for the development of more advanced and robust systems for assisting visually impaired individuals.By leveraging cutting-edge technologies and integrating them into amodular framework,this research contributes to creating a more inclusive and accessible society for individuals with visual impairments.Future work can focus on refining the system,addressing its limitations,and conducting user studies to evaluate its effectiveness and impact in real-world scenarios. 展开更多
关键词 Social networks text analytics emoji prediction features extraction information retrieval
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Physics-informed deep learning for fringe pattern analysis
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作者 Wei Yin Yuxuan Che +6 位作者 Xinsheng Li Mingyu Li Yan Hu Shijie Feng Edmund Y.Lam Qian Chen Chao Zuo 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期4-15,共12页
Recently,deep learning has yielded transformative success across optics and photonics,especially in optical metrology.Deep neural networks (DNNs) with a fully convolutional architecture (e.g.,U-Net and its derivatives... Recently,deep learning has yielded transformative success across optics and photonics,especially in optical metrology.Deep neural networks (DNNs) with a fully convolutional architecture (e.g.,U-Net and its derivatives) have been widely implemented in an end-to-end manner to accomplish various optical metrology tasks,such as fringe denoising,phase unwrapping,and fringe analysis.However,the task of training a DNN to accurately identify an image-to-image transform from massive input and output data pairs seems at best naive,as the physical laws governing the image formation or other domain expertise pertaining to the measurement have not yet been fully exploited in current deep learning practice.To this end,we introduce a physics-informed deep learning method for fringe pattern analysis (PI-FPA) to overcome this limit by integrating a lightweight DNN with a learning-enhanced Fourier transform profilometry (Le FTP) module.By parameterizing conventional phase retrieval methods,the Le FTP module embeds the prior knowledge in the network structure and the loss function to directly provide reliable phase results for new types of samples,while circumventing the requirement of collecting a large amount of high-quality data in supervised learning methods.Guided by the initial phase from Le FTP,the phase recovery ability of the lightweight DNN is enhanced to further improve the phase accuracy at a low computational cost compared with existing end-to-end networks.Experimental results demonstrate that PI-FPA enables more accurate and computationally efficient single-shot phase retrieval,exhibiting its excellent generalization to various unseen objects during training.The proposed PI-FPA presents that challenging issues in optical metrology can be potentially overcome through the synergy of physics-priors-based traditional tools and data-driven learning approaches,opening new avenues to achieve fast and accurate single-shot 3D imaging. 展开更多
关键词 optical metrology deep learning physics-informed neural networks fringe analysis phase retrieval
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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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Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China
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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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Importance-aware 3D volume visualization for medical content-based image retrieval-a preliminary study
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作者 Mingjian LI Younhyun JUNG +1 位作者 Michael FULHAM Jinman KIM 《虚拟现实与智能硬件(中英文)》 EI 2024年第1期71-81,共11页
Background A medical content-based image retrieval(CBIR)system is designed to retrieve images from large imaging repositories that are visually similar to a user′s query image.CBIR is widely used in evidence-based di... Background A medical content-based image retrieval(CBIR)system is designed to retrieve images from large imaging repositories that are visually similar to a user′s query image.CBIR is widely used in evidence-based diagnosis,teaching,and research.Although the retrieval accuracy has largely improved,there has been limited development toward visualizing important image features that indicate the similarity of retrieved images.Despite the prevalence of 3D volumetric data in medical imaging such as computed tomography(CT),current CBIR systems still rely on 2D cross-sectional views for the visualization of retrieved images.Such 2D visualization requires users to browse through the image stacks to confirm the similarity of the retrieved images and often involves mental reconstruction of 3D information,including the size,shape,and spatial relations of multiple structures.This process is time-consuming and reliant on users'experience.Methods In this study,we proposed an importance-aware 3D volume visualization method.The rendering parameters were automatically optimized to maximize the visibility of important structures that were detected and prioritized in the retrieval process.We then integrated the proposed visualization into a CBIR system,thereby complementing the 2D cross-sectional views for relevance feedback and further analyses.Results Our preliminary results demonstrate that 3D visualization can provide additional information using multimodal positron emission tomography and computed tomography(PETCT)images of a non-small cell lung cancer dataset. 展开更多
关键词 Volume visualization DVR Medical CBIR RETRIEVAL Medical images
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Evaluation of the Effect of Assessment Method Reform in “Nursing Research” Course
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作者 Yunling Li Dandan Hu 《Journal of Contemporary Educational Research》 2024年第3期7-12,共6页
Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Student... Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Students’mastery of key knowledge in“Nursing Research”was assessed through group reports on topic selection and literature retrieval,as well as the proposition level of the final examination.Results:81.6%of the students agreed with the course assessment method,and 97.9%believed studying“Nursing Research”would be helpful for future scientific research applications.Conclusion:Diversified assessment methods can help improve undergraduate nursing students’scientific research skills and comprehensive quality. 展开更多
关键词 Nursing Research Proposition assessment Undergraduate nursing students Topic selection Literature retrieval
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A Visual Indoor Localization Method Based on Efficient Image Retrieval
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作者 Mengyan Lyu Xinxin Guo +1 位作者 Kunpeng Zhang Liye Zhang 《Journal of Computer and Communications》 2024年第2期47-66,共20页
The task of indoor visual localization, utilizing camera visual information for user pose calculation, was a core component of Augmented Reality (AR) and Simultaneous Localization and Mapping (SLAM). Existing indoor l... The task of indoor visual localization, utilizing camera visual information for user pose calculation, was a core component of Augmented Reality (AR) and Simultaneous Localization and Mapping (SLAM). Existing indoor localization technologies generally used scene-specific 3D representations or were trained on specific datasets, making it challenging to balance accuracy and cost when applied to new scenes. Addressing this issue, this paper proposed a universal indoor visual localization method based on efficient image retrieval. Initially, a Multi-Layer Perceptron (MLP) was employed to aggregate features from intermediate layers of a convolutional neural network, obtaining a global representation of the image. This approach ensured accurate and rapid retrieval of reference images. Subsequently, a new mechanism using Random Sample Consensus (RANSAC) was designed to resolve relative pose ambiguity caused by the essential matrix decomposition based on the five-point method. Finally, the absolute pose of the queried user image was computed, thereby achieving indoor user pose estimation. The proposed indoor localization method was characterized by its simplicity, flexibility, and excellent cross-scene generalization. Experimental results demonstrated a positioning error of 0.09 m and 2.14° on the 7Scenes dataset, and 0.15 m and 6.37° on the 12Scenes dataset. These results convincingly illustrated the outstanding performance of the proposed indoor localization method. 展开更多
关键词 Visual Indoor Positioning Feature Point Matching Image Retrieval Position Calculation Five-Point Method
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A Study on Retrieving Atmospheric Profiles from EOS/AIRS Observations 被引量:11
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作者 官莉 ALLEN Huang 李俊 《Acta meteorologica Sinica》 SCIE 2005年第1期112-119,共8页
The paper presents the algorithms for retrieving atmospheric temperature andmoisture profiles and surface skin temperature from the high-spectral-resolution AtmosphericInfrared Sounder (AIRS) with a statistical techni... The paper presents the algorithms for retrieving atmospheric temperature andmoisture profiles and surface skin temperature from the high-spectral-resolution AtmosphericInfrared Sounder (AIRS) with a statistical technique based on principal component analysis. Thesynthetic regression coefficients for the statistical retrieval are obtained by using a fastradiative transfer model with atmospheric characteristics taken from a dataset of global radiosondesof atmospheric temperature and moisture profiles. Retrievals are evaluated by comparison withradiosonde observations and European Center of Medium-Range Weather Forecasts (ECMWF) analyses. AIRSretrievals of temperature and moisture are in general agreement with the distributions from ECMWFanalysis fields and radiosonde observations, but AIRS depicts more detailed structure due to itshigh spectral resolution (hence, high vertical spatial resolution). 展开更多
关键词 AIRS (Atmospheric Infrared Sounder) principal component regression atmospheric profile retrieval
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