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Research on the Development Strategies of Realtime Data Analysis and Decision-support Systems
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作者 Wei Tang 《Journal of Electronic Research and Application》 2025年第2期204-210,共7页
With the advent of the big data era,real-time data analysis and decision-support systems have been recognized as essential tools for enhancing enterprise competitiveness and optimizing the decision-making process.This... With the advent of the big data era,real-time data analysis and decision-support systems have been recognized as essential tools for enhancing enterprise competitiveness and optimizing the decision-making process.This study aims to explore the development strategies of real-time data analysis and decision-support systems,and analyze their application status and future development trends in various industries.The article first reviews the basic concepts and importance of real-time data analysis and decision-support systems,and then discusses in detail the key technical aspects such as system architecture,data collection and processing,analysis methods,and visualization techniques. 展开更多
关键词 Real-time data analysis Decision-support system Big data System architecture data processing Visualization technology
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From Static and Dynamic Perspectives:A Survey on Historical Data Benchmarks of Control Performance Monitoring 被引量:1
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作者 Pengyu Song Jie Wang +1 位作者 Chunhui Zhao Biao Huang 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期300-316,共17页
In recent decades,control performance monitoring(CPM)has experienced remarkable progress in research and industrial applications.While CPM research has been investigated using various benchmarks,the historical data be... In recent decades,control performance monitoring(CPM)has experienced remarkable progress in research and industrial applications.While CPM research has been investigated using various benchmarks,the historical data benchmark(HIS)has garnered the most attention due to its practicality and effectiveness.However,existing CPM reviews usually focus on the theoretical benchmark,and there is a lack of an in-depth review that thoroughly explores HIS-based methods.In this article,a comprehensive overview of HIS-based CPM is provided.First,we provide a novel static-dynamic perspective on data-level manifestations of control performance underlying typical controller capacities including regulation and servo:static and dynamic properties.The static property portrays time-independent variability in system output,and the dynamic property describes temporal behavior driven by closed-loop feedback.Accordingly,existing HIS-based CPM approaches and their intrinsic motivations are classified and analyzed from these two perspectives.Specifically,two mainstream solutions for CPM methods are summarized,including static analysis and dynamic analysis,which match data-driven techniques with actual controlling behavior.Furthermore,this paper also points out various opportunities and challenges faced in CPM for modern industry and provides promising directions in the context of artificial intelligence for inspiring future research. 展开更多
关键词 Control performance monitoring(CPM) datadriven method historical data benchmark(HIS) industrial process performance index static and dynamic analysis.
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Automation and parallelization scheme to accelerate pulsar observation data processing
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作者 Xingnan Zhang Minghui Li 《Astronomical Techniques and Instruments》 2025年第4期226-238,共13页
Previous studies aiming to accelerate data processing have focused on enhancement algorithms,using the graphics processing unit(GPU)to speed up programs,and thread-level parallelism.These methods overlook maximizing t... Previous studies aiming to accelerate data processing have focused on enhancement algorithms,using the graphics processing unit(GPU)to speed up programs,and thread-level parallelism.These methods overlook maximizing the utilization of existing central processing unit(CPU)resources and reducing human and computational time costs via process automation.Accordingly,this paper proposes a scheme,called SSM,that combines“Srun job submission mode”,“Sbatch job submission mode”,and“Monitor function”.The SSM scheme includes three main modules:data management,command management,and resource management.Its core innovations are command splitting and parallel execution.The results show that this method effectively improves CPU utilization and reduces the time required for data processing.In terms of CPU utilization,the average value of this scheme is 89%.In contrast,the average CPU utilizations of“Srun job submission mode”and“Sbatch job submission mode”are significantly lower,at 43%and 52%,respectively.In terms of the data-processing time,SSM testing on the Five-hundred-meter Aperture Spherical radio Telescope(FAST)data requires only 5.5 h,compared with 8 h in the“Srun job submission mode”and 14 h in the“Sbatch job submission mode”.In addition,tests on the FAST and Parkes datasets demonstrate the universality of the SSM scheme,which can process data from different telescopes.The compatibility of the SSM scheme for pulsar searches is verified using 2 days of observational data from the globular cluster M2,with the scheme successfully discovering all published pulsars in M2. 展开更多
关键词 Astronomical data Parallel processing PulsaR Exploration and Search TOolkit(PRESTO) CPU fast Parkes
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Analysis of the Impact of Legal Digital Currencies on Bank Big Data Practices
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作者 Zhengkun Xiu 《Journal of Electronic Research and Application》 2025年第1期23-27,共5页
This paper analyzes the advantages of legal digital currencies and explores their impact on bank big data practices.By combining bank big data collection and processing,it clarifies that legal digital currencies can e... This paper analyzes the advantages of legal digital currencies and explores their impact on bank big data practices.By combining bank big data collection and processing,it clarifies that legal digital currencies can enhance the efficiency of bank data processing,enrich data types,and strengthen data analysis and application capabilities.In response to future development needs,it is necessary to strengthen data collection management,enhance data processing capabilities,innovate big data application models,and provide references for bank big data practices,promoting the transformation and upgrading of the banking industry in the context of legal digital currencies. 展开更多
关键词 Legal digital currency Bank big data data processing efficiency data analysis and application Countermeasures and suggestions
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Preliminary exploration of constructing a standardized process for prognostic biomarker discovery based on genetic big data
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作者 Wang Min Yang Yongqi Li Xiawei 《China Standardization》 2025年第3期60-64,共5页
The paper utilized a standardized methodology to identify prognostic biomarkers in hepatocellular carcinoma(HCC)by analyzing transcriptomic and clinical data from The Cancer Genome Atlas(TCGA)database.The approach,whi... The paper utilized a standardized methodology to identify prognostic biomarkers in hepatocellular carcinoma(HCC)by analyzing transcriptomic and clinical data from The Cancer Genome Atlas(TCGA)database.The approach,which included stringent data preprocessing,differential gene expression analysis,and Kaplan-Meier survival analysis,provided valuable insights into the genetic underpinnings of HCC.The comprehensive analysis of a dataset involving 370 HCC patients uncovered correlations between survival status and pathological characteristics,including tumor size,lymph node involvement,and distant metastasis.The processed transcriptome dataset,comprising 420 samples and annotating 26,783 genes,served as a robust platform for identifying differential gene expression patterns.Among the significant differential expression genes,the key genes such as FBXO43,HAGLROS,CRISPLD1,LRRC3.DT,and ERN2,were pinpointed,which showed significant associations with patient survival outcomes,indicating their potential as novel prognostic biomarkers.This study can not only enhance the understanding of HCC’s genetic landscape but also establish a blueprint for a standardized process to discover prognostic biomarkers of various diseases using genetic big data.Future research should focus on validating these biomarkers through independent cohorts and exploring their utility in the development of personalized treatment strategies. 展开更多
关键词 standardized process genetic big data prognostic biomarkers Kaplan-Meier survival analysis hepatocellular carcinoma
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ADGAP:a user-friendly online ancient DNA database and genome analysis platform
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作者 Yanwei Chen Yu Xu +1 位作者 Kongyang Zhu Chuan-Chao Wang 《Journal of Genetics and Genomics》 2025年第8期1058-1061,共4页
The analysis of ancient genomics provides opportunities to explore human population history across both temporal and geographic dimensions(Haak et al.,2015;Wang et al.,2021,2024)to enhance the accessibility and utilit... The analysis of ancient genomics provides opportunities to explore human population history across both temporal and geographic dimensions(Haak et al.,2015;Wang et al.,2021,2024)to enhance the accessibility and utility of these ancient genomic datasets,a range of databases and advanced statistical models have been developed,including the Allen Ancient DNA Resource(AADR)(Mallick et al.,2024)and AdmixTools(Patterson et al.,2012).While upstream processes such as sequencing and raw data processing have been streamlined by resources like the AADR,the downstream analysis of these datasets-encompassing population genetics inference and spatiotemporal interpretation-remains a significant challenge.The AADR provides a unified collection of published ancient DNA(aDNA)data,yet its file-based format and reliance on command-line tools,such as those in Admix-Tools(Patterson et al.,2012),require advanced computational expertise for effective exploration and analysis.These requirements can present significant challenges forresearchers lackingadvanced computational expertise,limiting the accessibility and broader application of these valuable genomic resources. 展开更多
关键词 dataBASE raw data processing analysis ancient genomics upstream processes ancient DNA explore human population history allen ancient dna resource aadr mallick ancient genomic datasetsa
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Exploring the Effectiveness of Machine Learning and Deep Learning Algorithms for Sentiment Analysis:A Systematic Literature Review
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作者 Jungpil Shin Wahidur Rahman +5 位作者 Tanvir Ahmed Bakhtiar Mazrur Md.Mohsin Mia Romana Idress Ekfa Md.Sajib Rana Pankoo Kim 《Computers, Materials & Continua》 2025年第9期4105-4153,共49页
Sentiment Analysis,a significant domain within Natural Language Processing(NLP),focuses on extracting and interpreting subjective information-such as emotions,opinions,and attitudes-from textual data.With the increasi... Sentiment Analysis,a significant domain within Natural Language Processing(NLP),focuses on extracting and interpreting subjective information-such as emotions,opinions,and attitudes-from textual data.With the increasing volume of user-generated content on social media and digital platforms,sentiment analysis has become essential for deriving actionable insights across various sectors.This study presents a systematic literature review of sentiment analysis methodologies,encompassing traditional machine learning algorithms,lexicon-based approaches,and recent advancements in deep learning techniques.The review follows a structured protocol comprising three phases:planning,execution,and analysis/reporting.During the execution phase,67 peer-reviewed articles were initially retrieved,with 25 meeting predefined inclusion and exclusion criteria.The analysis phase involved a detailed examination of each study’s methodology,experimental setup,and key contributions.Among the deep learning models evaluated,Long Short-Term Memory(LSTM)networks were identified as the most frequently adopted architecture for sentiment classification tasks.This review highlights current trends,technical challenges,and emerging opportunities in the field,providing valuable guidance for future research and development in applications such as market analysis,public health monitoring,financial forecasting,and crisis management. 展开更多
关键词 Natural Language processing(NLP) Machine Learning(ML) sentiment analysis deep learning textual data
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Data Analysis Methods and Signal Processing Techniques in Gravitational Wave Detection
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作者 Bojun Yan 《Journal of Applied Mathematics and Physics》 2024年第11期3774-3783,共10页
Gravitational wave detection is one of the most cutting-edge research areas in modern physics, with its success relying on advanced data analysis and signal processing techniques. This study provides a comprehensive r... Gravitational wave detection is one of the most cutting-edge research areas in modern physics, with its success relying on advanced data analysis and signal processing techniques. This study provides a comprehensive review of data analysis methods and signal processing techniques in gravitational wave detection. The research begins by introducing the characteristics of gravitational wave signals and the challenges faced in their detection, such as extremely low signal-to-noise ratios and complex noise backgrounds. It then systematically analyzes the application of time-frequency analysis methods in extracting transient gravitational wave signals, including wavelet transforms and Hilbert-Huang transforms. The study focuses on discussing the crucial role of matched filtering techniques in improving signal detection sensitivity and explores strategies for template bank optimization. Additionally, the research evaluates the potential of machine learning algorithms, especially deep learning networks, in rapidly identifying and classifying gravitational wave events. The study also analyzes the application of Bayesian inference methods in parameter estimation and model selection, as well as their advantages in handling uncertainties. However, the research also points out the challenges faced by current technologies, such as dealing with non-Gaussian noise and improving computational efficiency. To address these issues, the study proposes a hybrid analysis framework combining physical models and data-driven methods. Finally, the research looks ahead to the potential applications of quantum computing in future gravitational wave data analysis. This study provides a comprehensive theoretical foundation for the optimization and innovation of gravitational wave data analysis methods, contributing to the advancement of gravitational wave astronomy. 展开更多
关键词 Gravitational Wave Detection data analysis Signal processing Matched Filtering Machine Learning
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Data processing and preliminary results of the Chang'e-3 VIS/NIR Imaging Spectrometer in-situ analysis 被引量:3
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作者 Bin Liu Chun-Lai Li +7 位作者 Guang-Liang Zhang Rui Xu Jian-Jun Liu Xin Ren Xu Tan Xiao-Xia Zhang Wei Zuo Wei-Bin Wen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1578-1594,共17页
The Chang'e-3 Visible and Near-infrared Imaging Spectrometer (VNIS) is one of the four payloads on the Yutu rover. After traversing the landing site during the first two lunar days, four different areas are detecte... The Chang'e-3 Visible and Near-infrared Imaging Spectrometer (VNIS) is one of the four payloads on the Yutu rover. After traversing the landing site during the first two lunar days, four different areas are detected, and Level 2A and 2B ra- diance data have been released to the scientific community. The released data have been processed by dark current subtraction, correction for the effect of temperature, radiometric calibration and geometric calibration. We emphasize approaches for re- flectance analysis and mineral identification for in-situ analysis with VNIS. Then the preliminary spectral and mineralogical results from the landing site are derived. After comparing spectral data from VNIS with data collected by the Ma instrument and samples of mare that were returned from the Apollo program, all the reflectance data have been found to have similar absorption features near 1000 nm except lunar sample 71061. In addition, there is also a weak absorption feature between 1750-2400nm on VNIS, but the slopes of VNIS and Ma reflectance at longer wavelengths are lower than data taken from samples of lunar mare. Spectral parameters such as Band Centers and Integrated Band Depth Ratios are used to analyze mineralogical features. The results show that detection points E and N205 are mixtures of high-Ca pyroxene and olivine, and the composition of olivineat point N205 is higher than that at point E, but the compositions of detection points S3 and N203 are mainly olivine-rich. Since there are no obvious absorption features near 1250 nm, plagioclase is not directly identified at the landing site. 展开更多
关键词 Chang'e-3 -- VNIS -- in-situ analysis -- data processing
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Polarimetric Meteorological Satellite Data Processing Software Classification Based on Principal Component Analysis and Improved K-Means Algorithm 被引量:1
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作者 Manyun Lin Xiangang Zhao +3 位作者 Cunqun Fan Lizi Xie Lan Wei Peng Guo 《Journal of Geoscience and Environment Protection》 2017年第7期39-48,共10页
With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In th... With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In this paper, a set of software classification method based on software operating characteristics is proposed. The method uses software run-time resource consumption to describe the software running characteristics. Firstly, principal component analysis (PCA) is used to reduce the dimension of software running feature data and to interpret software characteristic information. Then the modified K-means algorithm was used to classify the meteorological data processing software. Finally, it combined with the results of principal component analysis to explain the significance of various types of integrated software operating characteristics. And it is used as the basis for optimizing the allocation of software hardware resources and improving the efficiency of software operation. 展开更多
关键词 Principal COMPONENT analysis Improved K-Mean ALGORITHM METEOROLOGICAL data processing FEATURE analysis SIMILARITY ALGORITHM
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Development of the Data Processing and Analysis System Framework for ICF Experiments
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作者 杨冬 虞孝麒 张弛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第3期2872-2874,共3页
An idea is presented about the development of a data processing and analysis system for ICF experiments, which is based on an object oriented framework. The design and preliminary implementation of the data processing... An idea is presented about the development of a data processing and analysis system for ICF experiments, which is based on an object oriented framework. The design and preliminary implementation of the data processing and analysis framework based on the ROOT system have been completed. Software for unfolding soft X-ray spectra has been developed to test the functions of this framework. 展开更多
关键词 initial confinement fusion data processing and analysis object oriented framework ROOT soft X-ray spectra
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DATA PROCESSING OF UNIVERSAL QUANTITATIVE METHOD IN STANDARDLESS X-RAY PHASE ANALYSIS
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作者 LIN Shuzhi ZHANG Xizhang WANG Wenzhong, Institute of Metal Reaserch, Academia Sinica, Shenyang, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第11期348-353,共6页
Accuracy of coeffcient A_(isp) is related to the reference phase chosen during analysis. The cri- terion of choosing reference phase which may minimize the error of A_(isp) was deduced. The optimum results could be ob... Accuracy of coeffcient A_(isp) is related to the reference phase chosen during analysis. The cri- terion of choosing reference phase which may minimize the error of A_(isp) was deduced. The optimum results could be obtained by using the method of least squares if the number of sam- pies for analysis is more than the phase in samples. The procedure presented here is satisfacto- ryfor ordinary phase analysis. 展开更多
关键词 X-ray diffraction analysis data processing
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Data Processing and Analysis of Crustal Deformation Monitoring in West Antarctic Fildes Region
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作者 CHEN Chun-Ming E Dong-Chen QIU Wei-Ning 《冰川冻土》 CSCD 北大核心 1998年第4期301-305,共5页
In order to study contemporary crustal movement of Antarctic,China has not only constructed the deformation monitoring network in West Antarctic Fildes strait region,but also monitored the network by using DI-20 Geodi... In order to study contemporary crustal movement of Antarctic,China has not only constructed the deformation monitoring network in West Antarctic Fildes strait region,but also monitored the network by using DI-20 Geodimeter and GPS instruments,and participated the Antarctic GPS Campaign Observation organized by SCAR as well.During mathematics processing of crustal horizontal deformation observations,a method to bring deformation parameters into the error equations of observations is discussed in this paper.Several classical deformation models,such as rigid body displacement and strain,are introduced in detail.By analyzing the reference datum of statistical geodetic network,a conclusion is drawn that it is unfit to use rank-defected reference datum for the crustal deformation analysis,and another method is developed to set up different additional weight matrix for every different kind of parameter,the classical adjustment and rank-defected adjustment are well unified.Two methods of considering or non-considering the relation between point parameters and deformation parameters are compared,and the former is more appropriate than the latter.A series of programs are developed to implementing the method mentioned above and the analysis of West Antarctic Fileds deformation monitoring network.It is also involved GPS data processing and analysis of deformation results in the paper.The research results indicate that it seems exacting displacement in Fildes rift region,but the displacement is not large,just a little rift shear movement. 展开更多
关键词 ANTARCTIC deformation monitoring data processing strain analysis
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Data processing and analysis of crustal deformation monitoring in the Fildes region,West Antarctica
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作者 陈春明 鄂栋臣 邱卫宁 《Chinese Journal of Polar Science》 1997年第2期63-69,共7页
In order to research contemporary crustal movement of Antarctica, China has constructed the deformation monitoring network in the Fildes Strait region,West Antarctica, monitored the network by using DI 20 geodimeter... In order to research contemporary crustal movement of Antarctica, China has constructed the deformation monitoring network in the Fildes Strait region,West Antarctica, monitored the network by using DI 20 geodimeter and GPS instruments, and participated the Antarctic GPS Campaign Observation organized by SCAR as well. During mathematics processing of crustal horizontal deformation observations,a method to bring deformation parameters into the error equations of observations is discussed in this paper. Several classical deformation models,such as rigid body displacement and strain,are introduced. By analyzing the reference datum of static and dynamic geodetic network,the method is developed to set up different additional weight matrix for every different kind of parameter. A series of programs are developed to implementing the method mentioned above and the analysis of West Antarctic Fildes Strait deformation monitoring network. Discussion is also made of GPS monitoring data by using the principle of monitoring network strain analysis in the paper. The research results indicate that the displacement did occur in Fildes rift region,but the displacement was not large,just a slight rift shear movement. 展开更多
关键词 ANTARCTICA deformation monitoring data processing strain analysis.
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Chinese DeepSeek: Performance of Various Oversampling Techniques on Public Perceptions Using Natural Language Processing
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作者 Anees Ara Muhammad Mujahid +2 位作者 Amal Al-Rasheed Shaha Al-Otaibi Tanzila Saba 《Computers, Materials & Continua》 2025年第8期2717-2731,共15页
DeepSeek Chinese artificial intelligence(AI)open-source model,has gained a lot of attention due to its economical training and efficient inference.DeepSeek,a model trained on large-scale reinforcement learning without... DeepSeek Chinese artificial intelligence(AI)open-source model,has gained a lot of attention due to its economical training and efficient inference.DeepSeek,a model trained on large-scale reinforcement learning without supervised fine-tuning as a preliminary step,demonstrates remarkable reasoning capabilities of performing a wide range of tasks.DeepSeek is a prominent AI-driven chatbot that assists individuals in learning and enhances responses by generating insightful solutions to inquiries.Users possess divergent viewpoints regarding advanced models like DeepSeek,posting both their merits and shortcomings across several social media platforms.This research presents a new framework for predicting public sentiment to evaluate perceptions of DeepSeek.To transform the unstructured data into a suitable manner,we initially collect DeepSeek-related tweets from Twitter and subsequently implement various preprocessing methods.Subsequently,we annotated the tweets utilizing the Valence Aware Dictionary and sentiment Reasoning(VADER)methodology and the lexicon-driven TextBlob.Next,we classified the attitudes obtained from the purified data utilizing the proposed hybrid model.The proposed hybrid model consists of long-term,shortterm memory(LSTM)and bidirectional gated recurrent units(BiGRU).To strengthen it,we include multi-head attention,regularizer activation,and dropout units to enhance performance.Topic modeling employing KMeans clustering and Latent Dirichlet Allocation(LDA),was utilized to analyze public behavior concerning DeepSeek.The perceptions demonstrate that 82.5%of the people are positive,15.2%negative,and 2.3%neutral using TextBlob,and 82.8%positive,16.1%negative,and 1.2%neutral using the VADER analysis.The slight difference in results ensures that both analyses concur with their overall perceptions and may have distinct views of language peculiarities.The results indicate that the proposed model surpassed previous state-of-the-art approaches. 展开更多
关键词 DeepSeek PREDICTION natural language processing deep learning analysis TextBlob imbalance data
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Detecting the Lunar Wrinkle Ridges Through Deep Learning Based on DEM and Aspect Data
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作者 Xin Lu Jiacheng Sun +2 位作者 Gaofeng Shu Jianhui Zhao Ning Li 《Research in Astronomy and Astrophysics》 2025年第8期167-179,共13页
Lunar wrinkle ridges are an important stress geological structure on the Moon, which reflect the stress state and geological activity on the Moon. They provide important insights into the evolution of the Moon and are... Lunar wrinkle ridges are an important stress geological structure on the Moon, which reflect the stress state and geological activity on the Moon. They provide important insights into the evolution of the Moon and are key factors influencing future lunar activity, such as the choice of landing sites. However, automatic extraction of lunar wrinkle ridges is a challenging task due to their complex morphology and ambiguous features. Traditional manual extraction methods are time-consuming and labor-intensive. To achieve automated and detailed detection of lunar wrinkle ridges, we have constructed a lunar wrinkle ridge data set, incorporating previously unused aspect data to provide edge information, and proposed a Dual-Branch Ridge Detection Network(DBR-Net) based on deep learning technology. This method employs a dual-branch architecture and an Attention Complementary Feature Fusion module to address the issue of insufficient lunar wrinkle ridge features. Through comparisons with the results of various deep learning approaches, it is demonstrated that the proposed method exhibits superior detection performance. Furthermore, the trained model was applied to lunar mare regions, generating a distribution map of lunar mare wrinkle ridges;a significant linear relationship between the length and area of the lunar wrinkle ridges was obtained through statistical analysis, and six previously unrecorded potential lunar wrinkle ridges were detected. The proposed method upgrades the automated extraction of lunar wrinkle ridges to a pixel-level precision and verifies the effectiveness of DBR-Net in lunar wrinkle ridge detection. 展开更多
关键词 MOON methods:data analysis planets and satellites:surfaces techniques:image processing
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BYSpec:An Automatic Data Reduction Package for BFOSC and YFOSC Spectroscopic Data
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作者 Zi-Chong Zhang Jun-Bo Zhang +6 位作者 Ju-Jia Zhang De-Yang Song Jing Chen Ming-Yi Ding Nan Zhou Liang Wang Kai Zhang 《Research in Astronomy and Astrophysics》 2025年第2期182-196,共15页
BFOSC and YFOSC are the most frequently used instruments in the Xinglong 2.16 m telescope and Lijiang 2.4 m telescope,respectively.We developed a software package named“BYSpec”(BFOSC and YFOSC Spectra Reduction Pack... BFOSC and YFOSC are the most frequently used instruments in the Xinglong 2.16 m telescope and Lijiang 2.4 m telescope,respectively.We developed a software package named“BYSpec”(BFOSC and YFOSC Spectra Reduction Package)dedicated to automatically reducing the long-slit and echelle spectra obtained by these two instruments.The package supports bias and flat-fielding correction,order location,background subtraction,automatic wavelength calibration,and absolute flux calibration.The optimal extraction method maximizes the signal-to-noise ratio and removes most of the cosmic rays imprinted in the spectra.A comparison with the 1D spectra reduced with IRAF verifies the reliability of the results.This open-source software is publicly available to the community. 展开更多
关键词 methods:data analysis instrumentation:spectrographs techniques:image processing
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Machine Learning-based Identification of Contaminated Images in Light Curve Data Preprocessing
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作者 Hui Li Rong-Wang Li +1 位作者 Peng Shu Yu-Qiang Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期287-295,共9页
Attitude is one of the crucial parameters for space objects and plays a vital role in collision prediction and debris removal.Analyzing light curves to determine attitude is the most commonly used method.In photometri... Attitude is one of the crucial parameters for space objects and plays a vital role in collision prediction and debris removal.Analyzing light curves to determine attitude is the most commonly used method.In photometric observations,outliers may exist in the obtained light curves due to various reasons.Therefore,preprocessing is required to remove these outliers to obtain high quality light curves.Through statistical analysis,the reasons leading to outliers can be categorized into two main types:first,the brightness of the object significantly increases due to the passage of a star nearby,referred to as“stellar contamination,”and second,the brightness markedly decreases due to cloudy cover,referred to as“cloudy contamination.”The traditional approach of manually inspecting images for contamination is time-consuming and labor-intensive.However,we propose the utilization of machine learning methods as a substitute.Convolutional Neural Networks and SVMs are employed to identify cases of stellar contamination and cloudy contamination,achieving F1 scores of 1.00 and 0.98 on a test set,respectively.We also explore other machine learning methods such as ResNet-18 and Light Gradient Boosting Machine,then conduct comparative analyses of the results. 展开更多
关键词 techniques:image processing methods:data analysis light pollution
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Identification and classification of transient pulses observed in magnetometer array data by time-domain principal component analysis filtering 被引量:1
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作者 Karl N. Kappler Daniel D. Schneider +1 位作者 Laura S. MacLean Thomas E. Bleier 《Earthquake Science》 CSCD 2017年第4期193-207,共15页
A method for identification of pulsations in time series of magnetic field data which are simultaneously present in multiple channels of data at one or more sensor locations is described. Candidate pulsations of inter... A method for identification of pulsations in time series of magnetic field data which are simultaneously present in multiple channels of data at one or more sensor locations is described. Candidate pulsations of interest are first identified in geomagnetic time series by inspection. Time series of these "training events" are represented in matrix form and transpose-multiplied to generate time- domain covariance matrices. The ranked eigenvectors of this matrix are stored as a feature of the pulsation. In the second stage of the algorithm, a sliding window (approxi- mately the width of the training event) is moved across the vector-valued time-series comprising the channels on which the training event was observed. At each window position, the data covariance matrix and associated eigen- vectors are calculated. We compare the orientation of the dominant eigenvectors of the training data to those from the windowed data and flag windows where the dominant eigenvectors directions are similar. This was successful in automatically identifying pulses which share polarization and appear to be from the same source process. We apply the method to a case study of continuously sampled (50 Hz) data from six observatories, each equipped with three- component induction coil magnetometers. We examine a 90-day interval of data associated with a cluster of four observatories located within 50 km of Napa, California, together with two remote reference stations-one 100 km to the north of the cluster and the other 350 km south. When the training data contains signals present in the remote reference observatories, we are reliably able to identify and extract global geomagnetic signals such as solar-generated noise. When training data contains pulsations only observed in the cluster of local observatories, we identify several types of non-plane wave signals having similar polarization. 展开更多
关键词 Time series Magnetic fields Array data Signal processing Principal component analysis
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Discrimination of aqueous and vinegary extracts of Shixiao San using metabolomics coupled with multivariate data analysis and evaluation of antihyperlipidemic effect 被引量:1
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作者 Xiaofan Wang Xu Zhao +3 位作者 Liqiang Gu Yuanyuan Zhang Kaishun Bi Xiaohui Chen 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2014年第1期17-26,共10页
A novel study using LCeMS(Liquid chromatography tandem mass spectrometry)coupled with multivariate data analysis and bioactivity evaluation was established for discrimination of aqueous extract and vinegar extract of... A novel study using LCeMS(Liquid chromatography tandem mass spectrometry)coupled with multivariate data analysis and bioactivity evaluation was established for discrimination of aqueous extract and vinegar extract of Shixiao San.Batches of these two kinds of samples were subjected to analysis,and the datasets of sample codes,tR-m/z pairs and ion intensities were processed with principal component analysis(PCA).The result of score plot showed a clear classification of the aqueous and vinegar groups.And the chemical markers having great contributions to the differentiation were screened out on the loading plot.The identities of the chemical markers were performed by comparing the mass fragments and retention times with those of reference compounds and/or the known compounds published in the literatures.Based on the proposed strategy,quercetin-3-Oneohesperidoside,isorhamnetin-3-O-neohespeeridoside,kaempferol-3-O-neohesperidoside,isorhamnetin-3-O-rutinoside and isorhamnetin-3-O-(2G-a-l-rhamnosyl)-rutinoside were explored as representative markers in distinguishing the vinegar extract from the aqueous extract.The anti-hyperlipidemic activities of two processed extracts of Shixiao San were examined on serum levels of lipids,lipoprotein and blood antioxidant enzymes in a rat hyperlipidemia model,and the vinegary extract,exerting strong lipid-lowering and antioxidative effects,was superior to the aqueous extract.Therefore,boiling with vinegary was predicted as the greatest processing procedure for anti-hyperlipidemic effect of Shixiao San.Furthermore,combining the changes in the metabolic profiling and bioactivity evaluation,the five representative markers may be related to the observed antihyperlipidemic effect. 展开更多
关键词 Anti-hyperlipidemic effect Herb processing Multivariate data analysis Shixiao San Liquid chromatography tandem mass spectrometry
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