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Along-dipping variations in fault geometry influencing shallow-slip-deficit during the 2021 M_(W)7.4 Maduo earthquake
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作者 Zhen Li Chenglong Li Teng Wang 《Geodesy and Geodynamics》 2026年第1期120-129,共10页
The shallow slip deficit(SSD)during strike-slip earthquakes raises a question of how the strain budget is accommodated over multiple cycles.However,the origin of variable SSD observed in different earthquakes is still... The shallow slip deficit(SSD)during strike-slip earthquakes raises a question of how the strain budget is accommodated over multiple cycles.However,the origin of variable SSD observed in different earthquakes is still under debate because each earthquake has its unique initial stress condition.Here,we derive the slip model of the 2021 M_(W) 7.4 Maduo earthquake in Qinghai,China,using multi-track radar images.Our results revealed that,in contrast to the large SSD on segments close to the epicenter,a much smaller SSD was observed at the west terminus of the rupture,where aftershock distribution indicates that the fault changes dip direction at 6 km depth.The 2021 Maduo earthquake thus represents an extraordinary case of significant along-strike SSD variation.After accounting for interseismic,postseismic,and diffuse off-fault deformation,we find that this variation is likely contributed by the along-dipping geometrical variation,implying that a multi-segment earthquake may leave heterogeneous stress condition on the fault with different amounts of SSD. 展开更多
关键词 Maduo earthquake InSAR Shallow slip deficit Fault geometry
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Double Wilczek–Zee connection and mixed-state quantum geometric tensor
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作者 Xiaoguang Wang Xiao-Ming Lu +2 位作者 Jing Liu Wenkui Ding Libin Fu 《Chinese Physics B》 2026年第2期300-305,共6页
The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor... The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor(QGT),another important concept in the field of quantum geometry.The DWZC is Hermitian with respect to the two integer indices,just like the original Hermitian WZC.Based on the symmetric logarithmic derivative operator,we propose a mixed-state quantum geometric tensor.Using the symmetric properties of the DWZC,we find that the real part of the QGT is connected to the real part of the DWZC and the square of eigenvalue differences of the density matrix,whereas the imaginary part can be given in terms of the imaginary part of the DWZC and the cube of the eigenvalue differences.For density matrices with full rank or no full rank,the QGT can be given in terms of real and imaginary parts of the DWZC. 展开更多
关键词 quantum geometry Wilczek–Zee connection quantum geometric tensor
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Calculation of Viewing and Solar Geometry Angles for the Fengyun-4B Geostationary Satellite
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作者 Dazhi YANG Yuhang MA +2 位作者 Yun CAO Lei YANG Hai ZHANG 《Advances in Atmospheric Sciences》 2026年第4期736-743,共8页
The calculation of viewing and solar geometry angles is a critical first step in retrieving atmospheric and surface variables from geostationary satellite observations.Whereas the viewing angles for geostationary sate... The calculation of viewing and solar geometry angles is a critical first step in retrieving atmospheric and surface variables from geostationary satellite observations.Whereas the viewing angles for geostationary satellites are not timevarying,a primary source of inaccuracy in solar positioning is the use of a single timestamp.Since pixel scanning times can differ significantly across the field-of-view disk(e.g.,by approximately 13 min for Fengyun-4B),this practice leads to errors of up to±2°in solar zenith angle,which translates to±50 W m^(−2) in extraterrestrial irradiance;the errors in solar azimuth angle can exceed±100°.Beyond scanning time,this work also quantifies the impact of other inputs—including altitude,surface pressure,air temperature,difference between Terrestrial Time and Universal Time,and atmospheric refraction—on the resulting angles.A comparison of our precise calculations with the official National Satellite Meteorological Center L1_GEO product shows an accuracy within 0.1°,confirming its utility for most retrieval tasks.To facilitate higher precision when required,this work releases the corresponding satellite and solar positioning codes in both R and Python. 展开更多
关键词 Fengyun-4B viewing and solar geometry solar position algorithm geostationary satellite code availability
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Hyperbolic Fibonacci and Lucas Functions, “Golden” Fibonacci Goniometry, Bodnar’s Geometry, and Hilbert’s Fourth Problem—Part II. A New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) 被引量:2
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作者 Alexey Stakhov Samuil Aranson 《Applied Mathematics》 2011年第2期181-188,共8页
This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries–New ... This article refers to the “Mathematics of Harmony” by Alexey Stakhov in 2009, a new interdisciplinary direction of modern science. The main goal of the article is to describe two modern scientific discoveries–New Geometric Theory of Phyllotaxis (Bodnar’s Geometry) and Hilbert’s Fourth Problem based on the Hyperbolic Fibonacci and Lucas Functions and “Golden” Fibonacci λ-Goniometry (λ > 0 is a given positive real number). Although these discoveries refer to different areas of science (mathematics and theoretical botany), however they are based on one and the same scientific ideas-the “golden mean,” which had been introduced by Euclid in his Elements, and its generalization—the “metallic means,” which have been studied recently by Argentinian mathematician Vera Spinadel. The article is a confirmation of interdisciplinary character of the “Mathematics of Harmony”, which originates from Euclid’s Elements. 展开更多
关键词 Euclid’s Fifth Postulate Lobachevski’s geometry HYPERBOLIC geometry PHYLLOTAXIS Bodnar’s geometry Hilbert’s Fourth Problem The “Golden” and “Metallic” Means Binet Formukas HYPERBOLIC FIBONACCI and Lucas Functions Gazale Formulas “Golden” FIBONACCI λ-Goniometry
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High Speed Regular Expression Matching Engine with Fast Pre-Processing 被引量:1
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作者 Zhe Fu Jun Li 《China Communications》 SCIE CSCD 2019年第2期177-188,共12页
Regular expression matching is playing an important role in deep inspection. The rapid development of SDN and NFV makes the network more dynamic, bringing serious challenges to traditional deep inspection matching eng... Regular expression matching is playing an important role in deep inspection. The rapid development of SDN and NFV makes the network more dynamic, bringing serious challenges to traditional deep inspection matching engines. However, state-of-theart matching methods often require a significant amount of pre-processing time and hence are not suitable for this fast updating scenario. In this paper, a novel matching engine called BFA is proposed to achieve high-speed regular expression matching with fast pre-processing. Experiments demonstrate that BFA obtains 5 to 20 times more update abilities compared to existing regular expression matching methods, and scales well on multi-core platforms. 展开更多
关键词 deep inspection FINITE AUTOMATON REGULAR expression MATCHING pre-processing
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Pre-processing and post-processing method for geostress simulation using seismic interpretation results 被引量:1
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作者 ZHANG Li-hong 《Mining Science and Technology》 EI CAS 2009年第3期369-372,共4页
In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflec... In order to carry out numerical simulation using geologic structural data obtained from Landmark(seismic interpretation system), underground geological structures are abstracted into mechanical models which can reflect actual situations and facilitate their computation and analyses.Given the importance of model building, further processing methods about traditional seismic interpretation results from Landmark should be studied and the processed result can then be directly used in numerical simulation computations.Through this data conversion procedure, Landmark and FLAC(the international general stress software) are seamlessly connected.Thus, the format conversion between the two systems and the pre-and post-processing in simulation computation is realized.A practical application indicates that this method has many advantages such as simple operation, high accuracy of the element subdivision and high speed, which may definitely satisfy the actual needs of floor grid cutting. 展开更多
关键词 seismic interpretation numerical simulation pre-processing POST-PROCESSING COUPLING
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Concurrent multi-task pre-processing method for LEO mega-constellation based on dynamic spatio-temporal grids 被引量:1
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作者 Xibin CAO Ning LI Shi QIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第11期233-248,共16页
The Low Earth Orbit(LEO)remote sensing satellite mega-constellation has the characteristics of large quantity and various types which make it have unique superiority in the realization of concurrent multiple tasks.How... The Low Earth Orbit(LEO)remote sensing satellite mega-constellation has the characteristics of large quantity and various types which make it have unique superiority in the realization of concurrent multiple tasks.However,the complexity of resource allocation is increased because of the large number of tasks and satellites.Therefore,the primary problem of implementing concurrent multiple tasks via LEO mega-constellation is to pre-process tasks and observation re-sources.To address the challenge,we propose a pre-processing algorithm for the mega-constellation based on highly Dynamic Spatio-Temporal Grids(DSTG).In the first stage,this paper describes the management model of mega-constellation and the multiple tasks.Then,the coding method of DSTG is proposed,based on which the description of complex mega-constellation observation resources is realized.In the third part,the DSTG algorithm is used to realize the processing of concurrent multiple tasks at multiple levels,such as task space attribute,time attribute and grid task importance evaluation.Finally,the simulation result of the proposed method in the case of constellation has been given to verify the effectiveness of concurrent multi-task pre-processing based on DSTG.The autonomous processing process of task decomposition and task fusion and mapping to grids,and the convenient indexing process of time window are verified. 展开更多
关键词 LEO mega-constellation Concurrent multiple tasks Tasks pre-processing Highly dynamic spatiotemporal grids Multi-task fusion merging Importance evaluation
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Pre-processing filter design at transmitters for IBI mitigation in an OFDM system 被引量:1
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作者 Xia Wang Lei Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第5期722-728,共7页
In order to meet the demands for high transmission rates and high service quality in broadband wireless communication systems, orthogonal frequency division multiplexing (OFDM) has been adopted in some standards. Ho... In order to meet the demands for high transmission rates and high service quality in broadband wireless communication systems, orthogonal frequency division multiplexing (OFDM) has been adopted in some standards. However, the inter-block interference (IBI) and inter-carrier interference (ICI) in an OFDM system affect the performance. To mitigate IBI and ICI, some pre-processing approaches have been proposed based on full channel state information (CSI), which improved the system performance. A pre-processing filter based on partial CSI at the transmitter is designed and investigated. The filter coefficient is given by the optimization processing, the symbol error rate (SER) is tested, and the computation complexity of the proposed scheme is analyzed. Computer simulation results show that the proposed pre-processing filter can effectively mitigate IBI and ICI and the performance can be improved. Compared with pre-processing approaches at the transmitter based on full CSI, the proposed scheme has high spectral efficiency, limited CSI feedback and low computation complexity. 展开更多
关键词 pre-processing filter inter-block interference (IBI) mitigation limited feedback orthogonal frequency division multiplexing (OFDM).
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Fractal Geometry:Axioms,Fractal Derivative and Its Geometrical Meaning 被引量:1
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作者 V.K.Balkhanov 《Journal of Environmental & Earth Sciences》 2019年第1期1-5,共5页
Physics success is largely determined by using mathematics.Physics often themselves create the necessary mathematical apparatus.This article shows how you can construct a fractal calculus-mathematics of fractal geomet... Physics success is largely determined by using mathematics.Physics often themselves create the necessary mathematical apparatus.This article shows how you can construct a fractal calculus-mathematics of fractal geometry.In modem scientific literature often write from a firm that"there is no strict definition of fractals",to the more moderate that"objects in a certain sense,fractal and similar."We show that fractal geometry is a strict mathematical theory,defined by their axioms.This methodology allows the geometry of axiomatised naturally define fractal integrals and differentials.Consistent application on your input below the axiom gives the opportunity to develop effective methods of measurement of fractal dimension,geometri-cal interpretation of fractal derivative gain and open dual symmetry. 展开更多
关键词 FRACTAL geometry FRACTAL dimension FRACTAL CALCULUS DUALITY
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Scientific data products and the data pre-processing subsystem of the Chang'e-3 mission 被引量:1
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作者 Xu Tan Jian-Jun Liu +7 位作者 Chun-Lai Li Jian-Qing Feng Xin Ren Fen-Fei Wang Wei Yan Wei Zuo Xiao-Qian Wang Zhou-Bin Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1682-1694,共13页
The Chang'e-3 (CE-3) mission is China's first exploration mission on the surface of the Moon that uses a lander and a rover. Eight instruments that form the scientific payloads have the following objectives: (1... The Chang'e-3 (CE-3) mission is China's first exploration mission on the surface of the Moon that uses a lander and a rover. Eight instruments that form the scientific payloads have the following objectives: (1) investigate the morphological features and geological structures at the landing site; (2) integrated in-situ analysis of minerals and chemical compositions; (3) integrated exploration of the structure of the lunar interior; (4) exploration of the lunar-terrestrial space environment, lunar sur- face environment and acquire Moon-based ultraviolet astronomical observations. The Ground Research and Application System (GRAS) is in charge of data acquisition and pre-processing, management of the payload in orbit, and managing the data products and their applications. The Data Pre-processing Subsystem (DPS) is a part of GRAS. The task of DPS is the pre-processing of raw data from the eight instruments that are part of CE-3, including channel processing, unpacking, package sorting, calibration and correction, identification of geographical location, calculation of probe azimuth angle, probe zenith angle, solar azimuth angle, and solar zenith angle and so on, and conducting quality checks. These processes produce Level 0, Level 1 and Level 2 data. The computing platform of this subsystem is comprised of a high-performance computing cluster, including a real-time subsystem used for processing Level 0 data and a post-time subsystem for generating Level 1 and Level 2 data. This paper de- scribes the CE-3 data pre-processing method, the data pre-processing subsystem, data classification, data validity and data products that are used for scientific studies. 展开更多
关键词 Moon: data products -- methods: data pre-processing -- space vehicles:instruments
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Review of pre-processing technologies for ice cores
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作者 DU Wen-tao KANG Shi-chang +4 位作者 QIN Xiang SUN Wei-jun ZHANG Yu-lan LIU Yu-shuo CHEN Ji-zu 《Journal of Mountain Science》 SCIE CSCD 2018年第9期1950-1960,共11页
High-resolution ice core records covering long time spans enable reconstruction of the past climatic and environmental conditions allowing the investigation of the earth system's evolution.Preprocessing of ice cor... High-resolution ice core records covering long time spans enable reconstruction of the past climatic and environmental conditions allowing the investigation of the earth system's evolution.Preprocessing of ice cores has direct impacts on the data quality control for further analysis since the conventional ice core processing is time-consuming,produces qualitative data,leads to ice mass loss,and leads to risks of potential secondary pollution.However,over the past several decades,preprocessing of ice cores has received less attention than the improvement of ice drilling,the analytical methodology of various indices,and the researches on the climatic and environmental significance of ice core records.Therefore,this papers reviews the development of the processing for ice cores including framework,design as well as materials,analyzes the technical advantages and disadvantages of the different systems.In the past,continuous flowanalysis(CFA)has been successfully applied to process the polar ice cores.However,it is not suitable for ice cores outside polar region because of high level of particles,the memory effect between samples,and the filtration before injection.Ice core processing is a subtle and professional operation due to the fragility of the nonmetallic materials and the random distribution of particles and air bubbles in ice cores,which aggravates uncertainty in the measurements.The future developments of CFA are discussed in preprocessing,memory effect,challenge for brittle ice,coupling with real-time analysis and optimization of CFA in the field.Furthermore,non-polluting cutters with many different configurations could be designed to cut and scrape in multiple directions and to separate inner and outer portions of the core.This system also needs to be coupled with streamlined operation of packaging,coding,and stacking that can be implemented at high resolution and rate,avoiding manual intervention.At the same time,information of the longitudinal sections could be scanned andidentified,and then classified to obtain quantitative data.In addition,irregular ice volume and weight can also be obtained accurately.These improvements are recorded automatically via user-friendly interfaces.These innovations may be applied to other paleomedias with similar features and needs. 展开更多
关键词 Ice core Alpine region Polar region pre-processing INNOVATION
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Image pre-processing research of coal level in underground coal pocket
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作者 吴冰 高娜 《Journal of Coal Science & Engineering(China)》 2008年第1期162-164,共3页
Mathematical morphology is widely applicated in digital image procesing.Vari- ary morphology construction and algorithm being developed are used in deferent digital image processing.The basic idea of mathematical morp... Mathematical morphology is widely applicated in digital image procesing.Vari- ary morphology construction and algorithm being developed are used in deferent digital image processing.The basic idea of mathematical morphology is to use construction ele- ment measure image morphology for solving understand problem.The article presented advanced cellular neural network that forms mathematical morphological cellular neural network (MMCNN) equation to be suit for mathematical morphology filter.It gave the theo- ries of MMCNN dynamic extent and stable state.It is evidenced that arrived mathematical morphology filter through steady of dynamic process in definite condition. 展开更多
关键词 coal level pre-processing image stability neural network
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Geometrical Modeling of Crystal Structures with Use of Space of Elliptic Riemannian Geometry
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作者 Stanislav Rudnev Boris Semukhin Andrey Klishin 《Materials Sciences and Applications》 2011年第6期526-536,共11页
The space of internal geometry of a model of a real crystal is supposed to be finite, closed, and with a constant Gaussian curvature equal to unity, permitting the realization of lattice systems in accordance with Fed... The space of internal geometry of a model of a real crystal is supposed to be finite, closed, and with a constant Gaussian curvature equal to unity, permitting the realization of lattice systems in accordance with Fedorov groups of transformations. For visualizing computations, the interpretation of geometrical objects on a Clifford surface (SK) in Riemannian geometry with the help of a 2D torus in a Euclidean space is used. The F-algorithm ensures a computation of 2D sections of models of point systems arranged perpendicularly to the symmetry axes l3, l4, and l6. The results of modeling can be used for calculations of geometrical sizes of crystal structures, nanostructures, parameters of the cluster organization of oxides, as well as for the development of practical applications connected with improving the structural characteristics of crystalline materials. 展开更多
关键词 F-Algorithm Crystal LATTICE Systems Microstructure RIEMANNIAN geometry SPACE of Interpretation
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Intelligent Data Pre-processing Model in Integrated Ocean Observing Network System
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作者 韩华 丁永生 刘凤鸣 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期499-502,共4页
There are a number of dirty data in observation data set derived from integrated ocean observing network system. Thus, the data must be carefully and reasonably processed before they are used for forecasting or analys... There are a number of dirty data in observation data set derived from integrated ocean observing network system. Thus, the data must be carefully and reasonably processed before they are used for forecasting or analysis. This paper proposes a data pre-processing model based on intelligent algorithms. Firstly, we introduce the integrated network platform of ocean observation. Next, the preprocessing model of data is presemed, and an imelligent cleaning model of data is proposed. Based on fuzzy clustering, the Kohonen clustering network is improved to fulfill the parallel calculation of fuzzy c-means clustering. The proposed dynamic algorithm can automatically f'md the new clustering center with the updated sample data. The rapid and dynamic performance of the model makes it suitable for real time calculation, and the efficiency and accuracy of the model is proved by test results through observation data analysis. 展开更多
关键词 integrated ocean observing network intelligentdata pre-processing data cleaning fuzzy soft clustering
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Signal pre-processing method and application design of edge nodes for distributed electromechanical system
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作者 LIU Peijin ZHANG Xiangxiang +2 位作者 SUN Yu SHI Mengtao HE Ning 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第3期272-280,共9页
A signal pre-processing method based on optimal variational mode decomposition(OVMD)is proposed to improve the efficiency and accuracy of local data filtering and analysis of edge nodes in distributed electromechanica... A signal pre-processing method based on optimal variational mode decomposition(OVMD)is proposed to improve the efficiency and accuracy of local data filtering and analysis of edge nodes in distributed electromechanical systems.Firstly,the singular points of original signals are eliminated effectively by using the first-order difference method.Then the OVMD method is applied for signal modal decomposition.Furthermore,correlation analysis is conducted to determine the degree of correlation between each mode and the original signal,so as to accurately separate the real operating signal from noise signal.On the basis of theoretical analysis and simulation,an edge node pre-processing system for distributed electromechanical system is designed.Finally,by virtue of the signal-to-noise ratio(SNR)and root-mean-square error(RMSE)indicators,the signal pre-processing effect is evaluated.The experimental results show that the OVMD-based edge node pre-processing system can extract signals with different characteristics and improve the SNR of reconstructed signals.Due to its high fidelity and reliability,this system can also provide data quality assurance for subsequent system health monitoring and fault diagnosis. 展开更多
关键词 distributed electromechanical system electromechanical signal edge node optimal variational mode decomposition(OVMD) signal pre-processing system
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The Pre-processing Parallel Algorithm of A Sparse Linear Equation Group
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作者 Cao Ying 《International English Education Research》 2015年第1期96-98,共3页
The solution of linear equation group can be applied to the oil exploration, the structure vibration analysis, the computational fluid dynamics, and other fields. When we make the in-depth analysis of some large or ve... The solution of linear equation group can be applied to the oil exploration, the structure vibration analysis, the computational fluid dynamics, and other fields. When we make the in-depth analysis of some large or very large complicated structures, we must use the parallel algorithm with the aid of high-performance computers to solve complex problems. This paper introduces the implementation process having the parallel with sparse linear equations from the perspective of sparse linear equation group. 展开更多
关键词 Sparse Linear Equations pre-processing Parallel Algorithm
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The Role of Combined OSR and SDF Method for Pre-Processing of Microarray Data that Accounts for Effective Denoising and Quantification
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作者 Jayakishan Meher Mukesh Kumar Raval +1 位作者 Pramod Kumar Meher Gananath Dash 《Journal of Signal and Information Processing》 2011年第3期190-195,共6页
Microarray data is inherently noisy due to the noise contaminated from various sources during the preparation of microarray slide and thus it greatly affects the accuracy of the gene expression. How to eliminate the e... Microarray data is inherently noisy due to the noise contaminated from various sources during the preparation of microarray slide and thus it greatly affects the accuracy of the gene expression. How to eliminate the effect of the noise constitutes a challenging problem in microarray analysis. Efficient denoising is often a necessary and the first step to be taken before the image data is analyzed to compensate for data corruption and for effective utilization for these data. Hence preprocessing of microarray image is an essential to eliminate the background noise in order to enhance the image quality and effective quantification. Existing denoising techniques based on transformed domain have been utilized for microarray noise reduction with their own limitations. The objective of this paper is to introduce novel preprocessing techniques such as optimized spatial resolution (OSR) and spatial domain filtering (SDF) for reduction of noise from microarray data and reduction of error during quantification process for estimating the microarray spots accurately to determine expression level of genes. Besides combined optimized spatial resolution and spatial filtering is proposed and found improved denoising of microarray data with effective quantification of spots. The proposed method has been validated in microarray images of gene expression profiles of Myeloid Leukemia using Stanford Microarray Database with various quality measures such as signal to noise ratio, peak signal to noise ratio, image fidelity, structural content, absolute average difference and correlation quality. It was observed by quantitative analysis that the proposed technique is more efficient for denoising the microarray image which enables to make it suitable for effective quantification. 展开更多
关键词 DENOISING MICROARRAY pre-processing Quantification SPATIAL Domain Filtering Optimized SPATIAL Resolution Quality Measures
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Geometric parameter identification of bridge precast box girder sections based on deep learning and computer vision 被引量:4
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作者 JIA Jingwei NI Youhao +2 位作者 MAO Jianxiao XU Yinfei WANG Hao 《Journal of Southeast University(English Edition)》 2025年第3期278-285,共8页
To overcome the limitations of low efficiency and reliance on manual processes in the measurement of geometric parameters for bridge prefabricated components,a method based on deep learning and computer vision is deve... To overcome the limitations of low efficiency and reliance on manual processes in the measurement of geometric parameters for bridge prefabricated components,a method based on deep learning and computer vision is developed to identify the geometric parameters.The study utilizes a common precast element for highway bridges as the research subject.First,edge feature points of the bridge component section are extracted from images of the precast component cross-sections by combining the Canny operator with mathematical morphology.Subsequently,a deep learning model is developed to identify the geometric parameters of the precast components using the extracted edge coordinates from the images as input and the predefined control parameters of the bridge section as output.A dataset is generated by varying the control parameters and noise levels for model training.Finally,field measurements are conducted to validate the accuracy of the developed method.The results indicate that the developed method effectively identifies the geometric parameters of bridge precast components,with an error rate maintained within 5%. 展开更多
关键词 bridge precast components section geometry parameters size identification computer vision deep learning
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A ROOT-based detector geometry and event visualization system for JUNO-TAO
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作者 Ming-Hua Liao Kai-Xuan Huang +3 位作者 Yu-Mei Zhang Jia-Yang Xu Guo-Fu Cao Zheng-Yun You 《Nuclear Science and Techniques》 2025年第3期50-59,共10页
The Taishan Antineutrino Observatory(TAO)is a satellite experiment of the Jiangmen Underground Neutrino Observatory,located near the Taishan nuclear power plant(NPP).The TAO aims to measure the energy spectrum of reac... The Taishan Antineutrino Observatory(TAO)is a satellite experiment of the Jiangmen Underground Neutrino Observatory,located near the Taishan nuclear power plant(NPP).The TAO aims to measure the energy spectrum of reactor antineutrinos with unprecedented precision,which would benefit both reactor neutrino physics and the nuclear database.A detector geometry and event visualization system was developed for the TAO.The software was based on ROOT packages and embedded in the TAO offline software framework.This provided an intuitive tool for visualizing the detector geometry,tuning the reconstruction algorithm,understanding neutrino physics,and monitoring the operation of reactors at NPP.Further applications of the visualization system in the experimental operation of TAO and its future development are discussed. 展开更多
关键词 Visualization geometry Offline software JUNO TAO
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Response properties of geometries of coal penetrating fracture on seepage behavior
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作者 Penghua Han Kai Wang +2 位作者 Jiewen Pang Xiaofeng Ji Cun Zhang 《International Journal of Mining Science and Technology》 2025年第2期191-211,共21页
The fracture surfaces of coal-rock masses formed under mining-induced stress generally exhibit complex geometries, and the fracture geometry is one of the primary factors affecting the seepage characteristics of coal-... The fracture surfaces of coal-rock masses formed under mining-induced stress generally exhibit complex geometries, and the fracture geometry is one of the primary factors affecting the seepage characteristics of coal-rock penetrating fracture. This paper investigates the seepage characteristics of 5 groups of coal penetrating fracture(CPF) with different joint roughness coefficients(JRCs). Based on 3D morphology scanner tests and hydraulic coupling tests, a characterization method of effective geometric parameters in fracture surfaces under various confining pressures was improved, and a relationship between effective geometric parameters and the confining pressure is established. The results indicate that the nonlinear flow behavior in a CPF primarily includes three types: non-Newtonian fluid seepage under high confining pressure and low JRC, non-Darcy seepage under low confining pressure and high JRC, and the whole process of seepage characteristics between these two conditions. Among them, nonNewtonian fluid seepage is caused by significant fracture expansion, while non-Darcy seepage can be attributed to turbulence effects. During the seepage process, the geometric parameters with different JRC fracture samples all exhibit exponential changes with the increase of confining pressure. In addition,under high confining pressure, the effective contact ratio, effective fracture aperture, and void deviation ratio with high JRC fracture samples under high confining pressure increase by 93.5%, 67.4%, and 24.9%,respectively, compared with those of low JRC fracture samples. According to the variation of geometric parameters in a CPF with external stress, a seepage model considering geometric parameters in a CPF is proposed. By introducing the root mean square error(RMSE) and coefficient of determination(R2) to evaluate the error and goodness of fit between model curves and experimental data, it is found that the theoretical curves of model in this paper have the best matching with the experimental data. The average values of RMSE and R2for model in this paper are 0.002 and 0.70, respectively, which are better than models in the existing literature. 展开更多
关键词 Coal penetrating fracture ROUGHNESS GEOMETRIES Seepage characteristics
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