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Building Accurate Energy-Use Statistics for Data Centers 认领 引用
1
作者 Yong-Zhen Wang Te Han Yi-Ming Wei 《Engineering》 SCIE EI CSCD 2026年第5期336-342,共7页
With the rapid expansion of cloud computing and large-scale artificial intelligence models,building accurate and transparent energy-use statistics for data centers has become a critical challenge for global energy sys... With the rapid expansion of cloud computing and large-scale artificial intelligence models,building accurate and transparent energy-use statistics for data centers has become a critical challenge for global energy systems and climate governance.Existing studies report strikingly divergent estimates of global data center electricity consumption,ranging from 196 to 1200 TW·h in 2020,a more than sixfold difference.Such discrepancies reveal profound uncertainties and structural deficiencies in current energy accounting frameworks.Conventional estimation approaches rely heavily on indirect assumptions,proxy indicators,or highly aggregated regional and national statistics,obscuring the true electricity demand of data centers.This lack of statistical transparency distorts energy and carbon accounting,weakens power system planning,and constrains the effective integration of renewable energy with rapidly growing computing demand.This paper highlights that data centers should be treated as a distinct and strategically important end-use energy sector.It emphasizes the need for grid-informed energy registration,enhanced artificial intelligence identification techniques to improve the accuracy and verifiability of energy statistics.Furthermore,the paper emphasizes that policymakers should establish coordinated policy frameworks,enforce standardized energy reporting,and design appropriate incentive mechanisms to encourage data centers to participate in demand response programs and electricity markets,thereby unlocking load flexibility and supporting a secure,low-carbon energy transition. 展开更多
关键词 Data center Energy-use statistics Flexibility AI technologies
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Higher-Order Expansions of Powered Order Statistics of Maxwell Sequences 认领 引用
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作者 HUANG Jian-wen LIU Xin-ling +1 位作者 JIA Jin-ping WANG Run-ke 《Chinese Quarterly Journal of Mathematics》 2026年第2期162-173,共12页
Under the optimal norming constants, this paper studies the higher-order expansions of the distributions and densities of the powered order statistics of Maxwell sequence. As auxiliary results, the corresponding conve... Under the optimal norming constants, this paper studies the higher-order expansions of the distributions and densities of the powered order statistics of Maxwell sequence. As auxiliary results, the corresponding convergence rates are obtained. The results show that the convergence rates of distributions and densities of normalized power order statistics are related to power index in principle. Finally, we compared the accuracy of each approximations with its true values through numerical experiments. 展开更多
关键词 Maxwell sequences Powered order statistics Higher-order expansion Convergence rate
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Spectral statistics and wave-chaos transition in three-dimensional acoustic cavities 认领 引用
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作者 Xiaodong Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第6期714-722,共9页
We numerically study three-dimensional acoustic cavities with progressively increasing geometric complexity and analyze their spectral and spatial statistics.The eigenfrequency spectra and adjacent level-spacing ratio... We numerically study three-dimensional acoustic cavities with progressively increasing geometric complexity and analyze their spectral and spatial statistics.The eigenfrequency spectra and adjacent level-spacing ratios reveal a clear transition from Poisson to Gaussian orthogonal ensemble(GOE)statistics as the cavity structure becomes more irregular.The intermediate regimes are quantitatively characterized using the Berry–Robnik(BR)and Brody distributions,which yield consistent estimates of the chaotic fraction.Furthermore,both the participation ratio and long-range spectral correlations confirm the continuous evolution from integrable to chaotic dynamics.The distributions of normalized wavefunction amplitudes gradually approach the Gaussian prediction,indicating the onset of wave chaos.These results demonstrate that three-dimensional acoustic resonators provide a numerically controllable and experimentally accessible platform for studying the universal transition from Poisson to GOE statistics and for exploring the interplay between geometry and wave chaos. 展开更多
关键词 wave chaos spectral statistics acoustic resonators Poisson–GOE transition
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Two-Sample Order Statistics Estimator for SNR Estimation of Meteor Burst Communication Signals 认领 引用
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作者 Zhou Yanping Gao Rui 《China Communications》 SCIE EI CSCD 2026年第5期197-204,共8页
Meteor burst communication exploits transient meteor trails to enable beyond-line-of-sight transmission,where the inherently short-lived channel conditions impose stringent requirements on rapid and reliable signal-to... Meteor burst communication exploits transient meteor trails to enable beyond-line-of-sight transmission,where the inherently short-lived channel conditions impose stringent requirements on rapid and reliable signal-to-noise ratio estimation.This study proposes a novel pilotless SNR estimator founded on the two-sample order statistics method,which quantifies the distributional deviation between received signal amplitudes and pre-generated reference distributions without assuming a specific noise model.Comprehensive Monte Carlo simulations under BPSK,QPSK,and 16-QAM modulations in additive white Gaussian noise environments demonstrate that the proposed OS-based approach consistently surpasses the M2M4,M8,and Kolmogorov–Smirnov estimators in terms of estimation accuracy,normalized mean squared error,and success rate,with particularly notable gains in limited-sample scenarios.These results underscore the method’s robustness and adaptability for SNR estimation in MBC applications. 展开更多
关键词 meteor burst communication non-dataaided order statistics SNR estimation
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Construction and Application of a Knowledge Graph-Based Educational Question Answering System for Probability Theory and Mathematical Statistics 认领 引用
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作者 Yihan Huang 《Journal of Electronic Research and Application》 2026年第5期258-274,共17页
In recent years,with the rapid development of artificial intelligence and big data technologies,knowledge graphs have gained widespread attention and application.As a fundamental course in mathematics and statistics,P... In recent years,with the rapid development of artificial intelligence and big data technologies,knowledge graphs have gained widespread attention and application.As a fundamental course in mathematics and statistics,Probability Theory and Mathematical Statistics contains complex and highly interconnected knowledge points,making traditional learning methods less effective for understanding its internal logic.Therefore,constructing a knowledge graph and developing a corresponding question-answering system for this subject is of great significance.This project uses the Probability Theory and Mathematical Statistics Tutorial(3rd Edition)as the data source to construct a knowledge graph based on Neo4j.Cypher language and APOC tools were used for data import and graph construction,while Neo4j Bloom was employed for visualization.In addition,a question-answering system was developed using natural language processing techniques and the Flask framework to provide intelligent query services.The system can help students better understand and learn probability theory and mathematical statistics while reducing dependence on traditional textbooks. 展开更多
关键词 Knowledge graph Probability theory and mathematical statistics Neo4j NLP Question-answering system
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Land Statistics Data Management:Current Status,Challenges,and Improvements 认领 引用
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作者 Yuhui He 《Proceedings of Business and Economic Studies》 2026年第3期42-46,共5页
Land statistical data serves as a fundamental tool for converting land resources into quantifiable information,playing a vital role in supporting scientific decision-making,safeguarding rights and interests,and facili... Land statistical data serves as a fundamental tool for converting land resources into quantifiable information,playing a vital role in supporting scientific decision-making,safeguarding rights and interests,and facilitating regulatory enforcement.At present,China’s land statistical data management faces several practical challenges,including insufficient data coverage,opportunities for improving data accuracy,and underdeveloped interdepartmental information-sharing mechanisms.These issues have implications for the rational allocation and effective protection of land resources.This paper outlines the essential functions of land statistical data,analyzes current issues and their underlying causes,and proposes preliminary improvements related to data collection systems,data sharing,and quality control.These insights aim to contribute to the advancement of land resource management practices. 展开更多
关键词 Land statistical data Data quality Land management
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Reflections on the current state of spatial statistics education in the United States: 2014 认领 引用 被引量：1
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作者 Daniel A.GRIFFITH 《Geo-Spatial Information Science》 EI 2014年第4期229-235,共7页
This paper surveys the current state of teaching spatial statistics in the United States(US),with commentary about the future teaching of such a course.It begins with a historical overview,and proposes what constitute... This paper surveys the current state of teaching spatial statistics in the United States(US),with commentary about the future teaching of such a course.It begins with a historical overview,and proposes what constitutes suitable content for a contemporary spatial statistics course.It notes that contemporary university-level spatial statistics courses are mostly taught across myriad units,including biology/ecology,climatology,economics(as spatial econometrics),environmental studies,epidemiology/public health,forestry,geography,geosciences/earth sciences,geospatial information sciences,mathematics,quantitative social science,soil science,and statistics.It discusses the diffusion of this course across the US,which began in the mid-1980s.One result it reports is a model spatial statistics course offering. 展开更多
关键词 spatial statistics spatial statistics education spatial statistics courses the United States
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Teaching Reform and Practice of Statistics Courses in Big Data Management and Applications Major in the Context of New Quality Productivity 认领 引用
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作者 Tinghui Huang Junchao Dong Liang Min 《Journal of Contemporary Educational Research》 2025年第2期23-31,共9页
In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social developmen... In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social development.Consequently,many domestic universities have introduced majors or courses related to big data.Among these,the Big Data Management and Applications major stands out for its interdisciplinary approach and emphasis on practical skills.However,as an emerging field,it has not yet accumulated a robust foundation in teaching theory and practice.Current instructional practices face issues such as unclear training objectives,inconsistent teaching methods and course content,insufficient integration of practical components,and a shortage of qualified faculty-factors that hinder both the development of the major and the overall quality of education.Taking the statistics course within the Big Data Management and Applications major as an example,this paper examines the challenges faced by statistics education in the context of emerging productive forces and proposes corresponding improvement measures.By introducing innovative teaching concepts and strategies,the teaching system for professional courses is optimized,and authentic classroom scenarios are recreated through illustrative examples.Questionnaire surveys and statistical analyses of data collected before and after the teaching reforms indicate that the curriculum changes effectively enhance instructional outcomes,promote the development of the major,and improve the quality of talent cultivation. 展开更多
关键词 New quality productivity Big data Compound talents Statistics course Teaching examples
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Research on Teaching Practice and Strategies of Probability and Statistics Thinking in Middle Schools Empowered by Modern Educational Technology 认领 引用
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作者 Jin He Jiangtao Yu Zhaoyuan Zhang 《Journal of Contemporary Educational Research》 2025年第11期55-61,共7页
With the implementation of General Senior High School Mathematics Curriculum Standards(2017 Edition,Revised in 2020),probability and statistics,as important carriers of the core mathematical competencies“mathematical... With the implementation of General Senior High School Mathematics Curriculum Standards(2017 Edition,Revised in 2020),probability and statistics,as important carriers of the core mathematical competencies“mathematical modeling”and“data analysis,”have increasingly highlighted their educational value.By summarizing the historical evolution of probability and statistics thinking and combining with teaching practice cases,this study explores its unique role in cultivating students’core mathematical competencies.The research proposes a project-based teaching strategy relying on real scenarios and empowered by technology.Through cases,it demonstrates how to use modern educational technology to realize the whole-process exploration of data collection,model construction,and conclusion verification,so as to promote the transformation of middle school probability and statistics teaching from knowledge imparting to competency development,and provide a practical reference for curriculum reform. 展开更多
关键词 Probability and statistics Core competencies Modern educational technology Project-based learning Teaching strategies
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Exploration on the Ideological and Political Construction Path of the“Probability Theory and Mathematical Statistics”Course 认领 引用
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作者 Qianlong Dang Xiaofeng Yang Wenliang Wu 《Journal of Contemporary Educational Research》 2025年第10期85-91,共7页
This paper focuses on the ideological and political construction of the course“Probability Theory and Mathematical Statistics.”Aiming at the current situation in teaching where emphasis is placed on knowledge impart... This paper focuses on the ideological and political construction of the course“Probability Theory and Mathematical Statistics.”Aiming at the current situation in teaching where emphasis is placed on knowledge imparting while value guidance is neglected,and combined with the requirements of ideological and political education policies in the new era,this paper explores the integration path between professional courses and ideological and political education.Through literature analysis,case comparison,and empirical research,the study proposes a systematic implementation plan covering the design of teaching objectives,the reconstruction of teaching content,and the optimization of the evaluation system.The purpose is to cultivate students’sense of social responsibility and innovative awareness by excavating the ideological and political elements in mathematics.The research results provide practical reference for colleges and universities to deepen the reform of ideological and political education in courses,and promote the implementation of the fundamental task of fostering virtue through education in STEM education. 展开更多
关键词 Probability theory Mathematical statistics Ideological and political education in courses Fostering virtue through education Construction path
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Current Statistics System Fails to Reflect New Changes in International Trade Activities 认领 引用 被引量：2
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作者 万光彩 刘莉 《中国经济学人（中英文）》 2007年第3期90-97,共8页
Today developed countries mainly participate in international trade via their foreign affiliates and intermediate goods are more frequently traded as a result of increasingly deepening international divisions of labou... Today developed countries mainly participate in international trade via their foreign affiliates and intermediate goods are more frequently traded as a result of increasingly deepening international divisions of labour.Against this background,the current trade statistical system that is characterized by the statistical principle of cross-border trade and production,and the custom’s registration data collection method,greatly exaggerate the trade imbalance between China and America. Consequently,it is necessary for the Chinese nation to overcome the shortcomings of the current statistical system so as to evaluate more fairly the trade imbalance between China and America by referring to the Ownership-Based Framework of the complimentary statistical system under the US Current Account.This article, on the basis of the statistical principle of oumership,attempts to regulate the distorted trade imbalance resulting from the current trade statistical system,and aims for an increased understanding of the trade imbalance between China and America from a theoretical background,as well as from the points of view of practitioners and decision makers. 展开更多
关键词 Statistics system China-US trade imbalance Ownership-based statistics Trade deficit
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DOA Estimation Based on Sparse Representation of the Fractional Lower Order Statistics in Impulsive Noise 认领 引用 被引量：12
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作者 Sen Li Rongxi He +1 位作者 Bin Lin Fei Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第4期860-868,共9页
This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive ... This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive noise as α-stable distribution, new methods which combine the sparse signal representation technique and fractional lower order statistics theory are proposed. In the new algorithms, the fractional lower order statistics vectors of the array output signal are sparsely represented on an overcomplete basis and the DOAs can be effectively estimated by searching the sparsest coefficients. To enhance the robustness performance of the proposed algorithms,the improved algorithms are advanced by eliminating the fractional lower order statistics of the noise from the fractional lower order statistics vector of the array output through a linear transformation. Simulation results have shown the effectiveness of the proposed methods for a wide range of highly impulsive environments. 展开更多
关键词 α-stable distribution direction of arrival(DOA) fractional lower-order statistics impulsive noise sparse representation
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Reservoir parameter inversion based on weighted statistics 认领 引用 被引量：5
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作者 桂金咏 高建虎 +3 位作者 雍学善 李胜军 刘炳杨 赵万金 《Applied Geophysics》 SCIE CSCD 2015年第4期523-532,627,628,共10页
Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and ideal... Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and idealized models increases the uncertainties of the inversion result. Thus, we propose an inversion method that is different from traditional statistical rock physics modeling. First, we use deterministic and stochastic rock physics models considering the uncertainties of elastic parameters obtained by prestack seismic inversion and introduce weighting coefficients to establish a weighted statistical relation between reservoir and elastic parameters. Second, based on the weighted statistical relation, we use Markov chain Monte Carlo simulations to generate the random joint distribution space of reservoir and elastic parameters that serves as a sample solution space of an objective function. Finally, we propose a fast solution criterion to maximize the posterior probability density and obtain reservoir parameters. The method has high efficiency and application potential. 展开更多
关键词 Reservoir parameters inversion weighted statistics Bayesian framework stochastic simulation
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Statistics and Analysis of Lightning Flashovers of Transmission Lines During 2000-2007 认领 引用 被引量：16
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作者 LI Xiao-lan CHEN Jia-hong +1 位作者 GU Shan-qiang TONG Xue-fang 《高电压技术》 EI CAS 北大核心 2009年第3期705-710,共6页
Lightning stroke is one of the important causes of the accidents that occur on transmission lines.With the development of power system,the proportion of outages on transmission lines because of lightning stroke also i... Lightning stroke is one of the important causes of the accidents that occur on transmission lines.With the development of power system,the proportion of outages on transmission lines because of lightning stroke also increases.And according to the lightning accidents results,the lightning stroke characteristics is related to the time factors tightly.In order to analyze the correlativity between the lightning flashover amount and the time factors,about 425 times lightning flashover on 187 lines in 10 power supply companies of 220 kV and 500 kV transmission lines during 2000-2007 are investigated in this paper.The correlativity between the lightning flashover amount and the time factors is analyzed.According to the lightning stroke accidents investigation records,the lightning flashover amount of transmission line increases from the year of 2000 to 2007.In each year lightning flashovers mostly happen in the month of June,July and August.Similarly in each day the flashover amount also varies with the time of day obviously.These lightning flashovers mainly occur during 14:00-21:00 in the afternoon.The analysis results in this paper have a good agreement with the meteorological observations and lightning detection data of lightning location system(LLS).And these results provide good reference for the lightning protection work in power system. 展开更多
关键词 lightning flashover lightning stroke transmission line lightning detection lightning accidents classified statistics lightning location system
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Traffic Flow Statistics Method Based on Deep Learning and Multi-Feature Fusion 认领 引用 被引量：6
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作者 Liang Mu Hong Zhao +3 位作者 Yan Li Xiaotong Liu Junzheng Qiu Chuanlong Sun 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第11期465-483,共19页
Traffic flow statistics have become a particularly important part of intelligent transportation.To solve the problems of low real-time robustness and accuracy in traffic flow statistics.In the DeepSort tracking algori... Traffic flow statistics have become a particularly important part of intelligent transportation.To solve the problems of low real-time robustness and accuracy in traffic flow statistics.In the DeepSort tracking algorithm,the Kalman filter(KF),which is only suitable for linear problems,is replaced by the extended Kalman filter(EKF),which can effectively solve nonlinear problems and integrate the Histogram of Oriented Gradient(HOG)of the target.The multi-target tracking framework was constructed with YOLO V5 target detection algorithm.An efficient and longrunning Traffic Flow Statistical framework(TFSF)is established based on the tracking framework.Virtual lines are set up to record the movement direction of vehicles to more accurate and detailed statistics of traffic flow.In order to verify the robustness and accuracy of the traffic flow statistical framework,the traffic flow in different scenes of actual road conditions was collected for verification.The experimental validation shows that the accuracy of the traffic statistics framework reaches more than 93%,and the running speed under the detection data set in this paper is 32.7FPS,which can meet the real-time requirements and has a particular significance for the development of intelligent transportation. 展开更多
关键词 Deep learning multi-target tracking kalman filter histogram of oriented gradient traffic flow statistics
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Prediction of maximum carbon element content in continuous casting billets of 82B cord steel based on statistics of extreme values method 认领 引用 被引量：4
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作者 Dong-wei Guo Zi-bing Hou +3 位作者 Jiang-hai Cao Zhong-ao Guo Yi Chang Guang-hua Wen 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2020年第10期1163-1169,共7页
The research of carbon content along the casting direction of 82B cord steel billets is of great significance for improvingthe quality of cord products from subsequent processing.However,the traditional segregation an... The research of carbon content along the casting direction of 82B cord steel billets is of great significance for improvingthe quality of cord products from subsequent processing.However,the traditional segregation and billets quality evaluationmethods have certain limitations,such as sampling length and analysis area.which affect the accuracy of quality judgment.Thus.the statistics of extreme values(SEV)was introduced to predict the maximum value of carbon element contentalong the casting direction,which can quantitatively characterize the segregation degree.The size of the selected billet is150 mm×150 mm,and the sampling location is the centerline of the billet.The experiment was conducted by consideringthe effect of cooling intensity and casting speed on the maximum value of carbon element content.Firstly,the calculationresults show that the SEN method can predict the maximum value of carbon element content along the casting directionof 82B cord steel,and the SEV method is proved to be effective by analyzing the carbon distribution and fluctuation in billets.To some extent,the SEV method can break the limitations of the sampling length and analysis area by predicting themaximum value of carbon element on a larger range of continuous casting billets with few samples.During the continuouscasting process the increase in cooling intensity makes the surface shrinking rate increase,which can slow down the flowof solute-enriched liquid to the center,and the center segregation can be reduced.On the other hand,the function area ofthe final electromagnetic stirring can be expanded with the increase in the casting speed,which can reduce the concentration of carbon element in the center of the billets and reduce the maximum value of carbon element content.Ilt can providea new theoretical reference for the quantitative calculation of carbon content in continuous casting billets and the qualityevaluation of continuous casting billcts. 展开更多
关键词 Cord steel Continuous casting Casting direction Segregation Statistics of extreme values
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New Dynamic Algorithm for IRFPA Bad Pixel Detection and Compensation Based on Statistics 认领 引用 被引量：5
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作者 刘崇亮 金伟其 +1 位作者 曹扬 刘秀 《Journal of Beijing Institute of Technology》 EI CAS 2009年第4期463-467,共5页
Based on the analysis to the behavior of bad pixels, a statistics-based auto-detecting and compensation algorithm for bad pixels is proposed. The correcting process is divided into two stages： bad pixel detection and... Based on the analysis to the behavior of bad pixels, a statistics-based auto-detecting and compensation algorithm for bad pixels is proposed. The correcting process is divided into two stages： bad pixel detection and bad pixel compensation. The proposed detection algorithm is a combination of median filtering and statistic method. Single frame median filtering is used to locate approximate map, then statistic method and threshold value is used to get the accurate location map of bad pixels. When the bad pixel detection is done, neighboring pixel replacement algorithm is used to compensate them in real-time. The effectiveness of this approach is test- ed by applying it to I-IgCATe infrared video. Experiments on real infrared imaging sequences demonstrate that the proposed algorithm requires only a few frames to obtain high quality corrections. It is easy to combine with traditional static methods, update the pre-defined location map in real-time. 展开更多
关键词 infrared focal plane array （IRFPA） based on statistics bad pixel detection bad pixel compensation
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The p-value and model specification in statistics 认领 引用 被引量：2
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作者 Bokai Wang Zhirou Zhou +2 位作者 Hongyue Wang Xin M Tu Changyong Feng 《General Psychiatry》 CSCD 2019年第3期163-166,共4页
SUMMARY The p value has been widely used as a way to summarise the significance in data analysis. However, misuse and misinterpretation of the p value is common in practice. Our result shows that if the model specific... SUMMARY The p value has been widely used as a way to summarise the significance in data analysis. However, misuse and misinterpretation of the p value is common in practice. Our result shows that if the model specification is wrong, the distribution of the p value may be inappropriate, which makes the decision based on the p value invalid. 展开更多
关键词 p-value model specification statistics
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Aperture-averaged scintillation index and fade statistics in weak oceanic turbulence 认领 引用 被引量：2
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作者 Hao Wang Fu-Zeng Kang +2 位作者 Xuan Wang Wei Zhao Shu-Wei Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期320-328,共9页
With the rapid demand for underwater optical communication(UOC), studies of UOC degradation by oceanic turbulence have attached increasing attention worldwide and become a research hot-spot in recent years. Previous s... With the rapid demand for underwater optical communication(UOC), studies of UOC degradation by oceanic turbulence have attached increasing attention worldwide and become a research hot-spot in recent years. Previous studies used a simplified and inaccurate oceanic turbulence spectrum, in which the eddy diffusivity ratio between temperature and salinity is assumed to be unity and the outer scale of turbulence is assumed to be infinite. However, both assumptions are not true in most of the actual marine environments. In this paper, based on the Rytov theory in weak turbulence, we derive analytical expressions of "the aperture-averaged scintillation index"(SI) for both plane and spherical waves, which can clearly demonstrate how SI is influenced by several key factors in UOC. Then, typical fade statistics of the UOC system in weak turbulence is discussed including the probability of fade, the expected number of fades per time, the mean fade time,signal-to-noise ratio and bit error rate. Our results show that spherical wave is preferable in the UOC system in weak turbulence compared to plane wave, and the aperture-averaged effect has a significant impact on UOC system's performance.Our results can be used to determine those key parameters for designing the UOC system over reasonable ranges. 展开更多
关键词 underwater optical communication(UOC) aperture-averaged scintillation index fade statistics
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Stochastic structural optimization using particle swarm optimization, surrogate models and Bayesian statistics 认领 引用 被引量：9
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作者 Jongbin Im Jungsun Park 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第1期112-121,共10页
This paper focuses on a method to solve structural optimization problems using particle swarm optimization （PSO）, surrogate models and Bayesian statistics. PSO is a random/stochastic search algorithm designed to fin... This paper focuses on a method to solve structural optimization problems using particle swarm optimization （PSO）, surrogate models and Bayesian statistics. PSO is a random/stochastic search algorithm designed to find the global optimum. However, PSO needs many evaluations compared to gradient-based optimization. This means PSO increases the analysis costs of structural optimization. One of the methods to reduce computing costs in stochastic optimization is to use approximation techniques. In this work, surrogate models are used, including the response surface method （RSM） and Kriging. When surrogate models are used, there are some errors between exact values and approximated values. These errors decrease the reliability of the optimum values and discard the realistic approximation of using surrogate models. In this paper, Bayesian statistics is used to obtain more reliable results. To verify and confirm the efficiency of the proposed method using surrogate models and Bayesian statistics for stochastic structural optimization, two numerical examples are optimized, and the optimization of a hub sleeve is demonstrated as a practical problem. 展开更多
关键词 Bayesian statistics Kriging Particle swarm optimization （PSO） Response surface method （RSM）
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