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Performance analysis of multi-channel order statistics detector for range-spread target 被引量:5
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作者 Shuwen Xu Penglang Shui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期689-699,共11页
The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optima... The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optimal detector,which requires many processing channels.The structure of such optimal detector is complex.Therefore,a simpler quasi-optimal detector is then introduced.The quasi-optimal detector,called the strong scattering cells’ number dependent order statistics(SND-OS) detector,takes the form of an average of maximum strong scattering cells with a known number.If the number of strong scattering cells is unknown in real situation,the multi-channel order statistics(MC-OS) detector is used.In each channel,a various number of maximums scattered from target are averaged.Then,the false alarm probability analysis and thresholds sets for each channel are given,following the detection results presented by means of Monte Carlo simulation strategy based on simulated target model and three measured targets.In particular,the theoretical analysis and simulation results highlight that the MC-OS detector can efficiently detect range-spread targets in white Gaussian noise. 展开更多
关键词 order statistics strong scattering cell MULTI-CHANNEL range-spread target
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Analysis of linear weighted order statistics CFAR algorithm 被引量:1
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作者 孟祥伟 关键 何友 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期232-236,共5页
CFAR technique is widely used in radar targets detection fields. Traditional algorithm is cell averaging (CA), which can give a good detection performance in a relatively ideal environment. Recently, censoring techniq... CFAR technique is widely used in radar targets detection fields. Traditional algorithm is cell averaging (CA), which can give a good detection performance in a relatively ideal environment. Recently, censoring technique is adopted to make the detector perform robustly. Ordered statistic (OS) and trimmed mean (TM) methods are proposed. TM methods treat the reference samples which participate in clutter power estimates equally, but this processing will not realize the effective estimates of clutter power. Therefore, in this paper a quasi best weighted (QBW) order statistics algorithm is presented. In special cases, QBW reduces to CA and the censored mean level detector (CMLD). 展开更多
关键词 RADAR DETECTION CFAR order statistics.
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Passive Steganalysis Based on Higher Order Image Statistics of Curvelet Transform 被引量:1
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作者 S.Geetha Siva S.Sivatha Sindhu N.Kamaraj 《International Journal of Automation and computing》 EI 2010年第4期531-542,共12页
Steganographic techniques accomplish covert communication by embedding secret messages into innocuous digital images in ways that are imperceptible to the human eye. This paper presents a novel passive steganalysis st... Steganographic techniques accomplish covert communication by embedding secret messages into innocuous digital images in ways that are imperceptible to the human eye. This paper presents a novel passive steganalysis strategy in which the task is approached as a pattern classification problem. A critical part of the steganalyser design depends on the selection of informative features. This paper is aimed at proposing a novel attack with improved performance indices with the following implications: 1) employing higher order statistics from a curvelet sub-band image representation that offers better discrimination ability for detecting stego anomalies in images, as compared to other conventional wavelet transforms; 2) increasing the sensitivity and specificity of the system by the feature reduction phase; 3) realizing the system using an efficient classification engine, a neuro-C4.5 classifier, which provides better classification rate. An extensive experimental evaluation on a database containing 5600 clean and stego images shows that the proposed scheme is a state-of-the-art steganalyser that outperforms other previous steganalytic methods. 展开更多
关键词 Image steganalysis curvelet higher order statistics neuro-C4.5 classifier information forensics information security
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Statistics and Analysis of Lightning Flashovers of Transmission Lines During 2000-2007 被引量:4
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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 CSCD 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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Asymptotic Analysis for U-Statistics and Its Application to Von Mises Statistics
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作者 Timur Zubayraev 《Open Journal of Statistics》 2011年第3期139-144,共6页
Let - be i.i.d. random variables taking values in a measurable space ( Χ, B ). Let φ1: Χ →□ and φ: Χ2→□ be measurable functions. Assume that φ is symmetric, i.e. φ(x,y)=φ(y.x), for any x,y∈Χ . Consider U... Let - be i.i.d. random variables taking values in a measurable space ( Χ, B ). Let φ1: Χ →□ and φ: Χ2→□ be measurable functions. Assume that φ is symmetric, i.e. φ(x,y)=φ(y.x), for any x,y∈Χ . Consider U-statistic, assuming that Eφ1(Χ)=0, Eφ(x, X)=0 for all x∈X, Eφ2(x,X)<∞, Eφ21(X)<∞. We will provide bounds for ΔN=supx|F(x)-F0(x)-F1(x)|, where F is a distribution function of T and F0 , F1 are its limiting distribution function and Edgeworth correction respectively. Applications of these results are also provided for von Mises statistics case. 展开更多
关键词 U-statistics Von MISES statistics SYMMETRIC statistics
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Combinatorial analysis on spatial information statistics for the karst water environment in Guiyang,China 被引量:1
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作者 WANG Zhongmei ZHU Lijun +3 位作者 YANG Ruidong YANG Shengyuan DING Jianping YANG Genlan 《Chinese Journal Of Geochemistry》 EI CAS 2012年第2期195-203,共9页
The karst groundwater system is extremely vulnerable and easily contaminated by human activities.To understand the spatial distribution of contaminants in the groundwater of karst urban areas and contributors to the c... The karst groundwater system is extremely vulnerable and easily contaminated by human activities.To understand the spatial distribution of contaminants in the groundwater of karst urban areas and contributors to the contamination,this paper employs the spatial information statistics analysis theory and method to analyze the karst groundwater environment in Guiyang City.Based on the karst ground water quality data detected in 61 detection points of the research area in the last three years,we made Kriging evaluation isoline map with some ions in the karst groundwater,such as SO4 2-,Fe 3+,Mn 2+and F -,analyzed and evaluated the spatial distribution,extension and variation of four types of ions on the basis of this isoline map.The results of the analysis show that the anomaly areas of SO4 2-,Fe 3+,Mn 2+,Fand other ions are mainly located in Baba’ao,Mawangmiao and Sanqiao in northwestern Gui- yang City as well as in its downtown area by reasons of the original non-point source pollution and the contamination caused by human activities(industrial and domestic pollution). 展开更多
关键词 岩溶地下水 空间信息统计 地下水环境 贵阳市 组合分析 地下水污染 中国 人类活动
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Tourism Statistics and the Business Register in Italy: A Comparative Analysis and future Outlooks for Integration
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作者 Francesca Petrei Maria Teresa Santoro 《Journal of Statistical Science and Application》 2015年第1期1-15,共15页
After the proposal of a possible insertion of tourism statistics (supply side) (TS) into Framework Regulation Integrating Business Statistics (FR1BS) on which an interesting debate is in progress between Eurosta... After the proposal of a possible insertion of tourism statistics (supply side) (TS) into Framework Regulation Integrating Business Statistics (FR1BS) on which an interesting debate is in progress between Eurostat and NSls, Istat (Italian Institute of Statistics) has started a costs/benefits analysis of this integration. ASIA (Statistical Register of Active Enterprises), built up by Istat, represents in Italy the official source about the structure and the economic performance of the enterprises. ASIA, whose statistical units are enterprises of industry and services, has been developed through the statistical integration of different administrative sources, other minor archives available (covering particular sectors) and structural business statistics currently produced by Istat. The supply side TS are produced by lstat through surveys via Intermediate Bodies (Local Authorities): each Intermediate Body has its own local register of accommodation establishments based on Local Kind-of-activity unit (LKAU). In this paper, the results of a comparative analysis between the statistical units as recorded in ASIA and as surveyed by TS are presented; from first outcomes, considerable issues about data quality appear both at level of coverage for the three Nace groups of the TS (also underlined in the Methodological Manual on Tourism Statistics where for Italy a difference of 70% is reported) and for loss information relating to the location of the activities (switching from LKAU to Enterprises) as well as for timeliness (ASIA has two years of delay). Then, the administrative local tourism registers (LTR) are analysed to understand: how many they are, their dissemination in the Italian territories, their primary purpose and source, the variables contained, the frequency of updates. This preliminary analysis is needed to identify the operative activities that Istat, together with the Intermediate Bodies, should start to use administrative archives for statistical purposes and to develop a unique tourism satellite archive (TSA), facing many difficulties related to the reception of several LTR as well as methodological issues for record linkage. On the other hand, a TSA would lead numerous advantages: a unique and official list of internal accommodation establishments; a step towards integration of TS into FRIBS; a starting point to begin to use also administrative data produced by the Italian Police (mandatory communications on vips in the interests of public safety), having a comparison term to assess their coverage. 展开更多
关键词 business register tourism statistics integration between administrative and statistics source.
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Analysis on n-gram statistics and linguistic features of whole genome protein sequences
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作者 董启文 王晓龙 林磊 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第5期694-698,共5页
To obtain the statistical sequence analysis on a large number of genomic and proteomic sequences available for different organisms, the n-grams of whole genome protein sequences from 20 organisms were extracted. Their... To obtain the statistical sequence analysis on a large number of genomic and proteomic sequences available for different organisms, the n-grams of whole genome protein sequences from 20 organisms were extracted. Their linguistic features were analyzed by two tests: Zipf power law and Shannon entropy, developed for analysis of natural languages and symbolic sequences. The natural genome proteins and the artificial genome proteins were compared with each other and some statistical features of n-grams were discovered. The results show that: the n-grams of whole genome protein sequences approximately follow the Zipf law when n is larger than 4; the Shannon n-gram entropy of natural genome proteins is lower than that of artificial proteins; a simple uni-gram model can distinguish different organisms; there exist organism-specific usages of "phrases" in protein sequences. It is suggested that further detailed analysis on n-gram of whole genome protein sequences will result in a powerful model for mapping the relationship of protein sequence, structure and function. 展开更多
关键词 n-gram statistics protein sequence Zipf law
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Microarray Analysis Using Rank Order Statistics for ARCH Residual Empirical Process
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作者 Hiroko Kato Solvang Masanobu Taniguchi 《Open Journal of Statistics》 2017年第1期54-71,共18页
Statistical two-group comparisons are widely used to identify the significant differentially expressed (DE) signatures against a therapy response for microarray data analysis. We applied a rank order statistics based ... Statistical two-group comparisons are widely used to identify the significant differentially expressed (DE) signatures against a therapy response for microarray data analysis. We applied a rank order statistics based on an Autoregressive Conditional Heteroskedasticity (ARCH) residual empirical process to DE analysis. This approach was considered for simulation data and publicly available datasets, and was compared with two-group comparison by original data and Auto-regressive (AR) residual. The significant DE genes by the ARCH and AR residuals were reduced by about 20% - 30% to these genes by the original data. Almost 100% of the genes by ARCH are covered by the genes by the original data unlike the genes by AR residuals. GO enrichment and Pathway analyses indicate the consistent biological characteristics between genes by ARCH residuals and original data. ARCH residuals array data might contribute to refining the number of significant DE genes to detect the biological feature as well as ordinal microarray data. 展开更多
关键词 Time Series Model ARCH Wilcoxon Statistic VOLATILITY Deferentially EXPRESSED Gene SIGNATURES Two-Group Comparison Breast Cancer GEO GENOME-WIDE Expression Profiling GO analysis
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Statistics Analysis:FDI Obsorbing in Jan-Jun
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作者 Jovi Shu 《China's Foreign Trade》 2008年第14期000-000,共2页
According to China's Customs' statistics,from January to May 2008,the import and export volume of foreign- invested enterprises totaled US$563.612 billion,an increase of 21.28 percent over the same period of l... According to China's Customs' statistics,from January to May 2008,the import and export volume of foreign- invested enterprises totaled US$563.612 billion,an increase of 21.28 percent over the same period of last year,5.02 percent lower than the growth rate of the country (26.30 percent) in the same period,accounting for 55.69 percent of the total import and export of the country.(See Chart 1) 展开更多
关键词 USS statistics analysis THAN
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Parameter estimation for rigid body after micro-Doppler removal based on L-statistics in the radar analysis 被引量:2
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作者 Yong Wang Jian Kang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期457-467,共11页
In traditional inverse synthetic aperture radar (ISAR) imaging of moving targets with rotational parts, the micro-Doppler (m-D) effects caused by the rotational parts influence the quality of the radar images. Rec... In traditional inverse synthetic aperture radar (ISAR) imaging of moving targets with rotational parts, the micro-Doppler (m-D) effects caused by the rotational parts influence the quality of the radar images. Recently, L. Stankovic proposed an m-D removal method based on L-statistics, which has been proved effective and simple. The algorithm can extract the m-D effects according to different behaviors of signals induced by rotational parts and rigid bodies in time-frequency (T-F) domain. However, by removing m-D effects, some useful short time Fourier transform (STFT) samples of rigid bodies are also extracted, which induces the side lobe problem of rigid bodies. A parameter estimation method for rigid bodies after m-D removal is proposed, which can accurately re- cover rigid bodies and avoid the side lobe problem by only using m-D removal. Simulations are given to validate the effectiveness of the proposed method. 展开更多
关键词 parameter estimation L-statistics micro-Doppler (m-D) radar imaging.
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Statistics and Analysis on Papers Published on Journal ‘Advanced Technology of Electrical Engineering and Energy’ 被引量:1
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作者 QIN Jie LIN Liang-zhen QI Zhi-ping MA Yu-huan SHEN Guo-liao JING Bo-hong 《电工电能新技术》 CSCD 北大核心 2009年第4期76-80,共5页
The paper presented the statistics and analysis on papers published on the journal 'Advanced Technology of Electrical Engineering and Energy' from 1996 to 2008: the paper acceptance rate,the paper category,the... The paper presented the statistics and analysis on papers published on the journal 'Advanced Technology of Electrical Engineering and Energy' from 1996 to 2008: the paper acceptance rate,the paper category,the first author's affiliations,the top 7 first authors,the top 10 coauthors and also the journal evaluation indexes of the journal.It offers details of the journal to anyone interested,especially to our editorial board and our broad readers. 展开更多
关键词 《电工电能新技术》 期刊 读者 编辑工作
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A brief statistics and analysis on residential electricity consumption in China
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《Electricity》 1992年第1期57-58,共2页
The statistic data of residential electricity consumptionshown in the table P.58 are quoted from the EnergyStatistical Year Book published by the National Statistic Bureau andthe statistics issued by the Ministry of E... The statistic data of residential electricity consumptionshown in the table P.58 are quoted from the EnergyStatistical Year Book published by the National Statistic Bureau andthe statistics issued by the Ministry of Energy.The reason of the differences between the data from the twosaid sources is that the latter does not include the consumption sup-plied by the local small power sources.From the statistical data we can see that: 展开更多
关键词 ELECTRICITY RESIDENTIAL issued latter statistic BUREAU brief 五旦 doubled GENERA
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Cryo-EM Data Statistics and Theoretical Analysis of KaiC Hexamer
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作者 Xu Han Zhaolong Wu +1 位作者 Tian Yang Qi Ouyang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第7期24-29,共6页
Cryo-electron microscopy(cryo-EM) provides a powerful tool to resolve the structure of biological macromolecules in natural state. One advantage of cryo-EM technology is that different conformation states of a protein... Cryo-electron microscopy(cryo-EM) provides a powerful tool to resolve the structure of biological macromolecules in natural state. One advantage of cryo-EM technology is that different conformation states of a protein complex structure can be simultaneously built, and the distribution of different states can be measured. This provides a tool to push cryo-EM technology beyond just to resolve protein structures, but to obtain the thermodynamic properties of protein machines. Here, we used a deep manifold learning framework to get the conformational landscape of Kai C proteins, and further obtained the thermodynamic properties of this central oscillator component in the circadian clock by means of statistical physics. 展开更多
关键词 Cryo-EM Data statistics and Theoretical analysis of KaiC Hexamer
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Quality Analysis of Rural Economic Statistics
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作者 CAOYuan 《外文科技期刊数据库(文摘版)经济管理》 2022年第6期118-121,共4页
There will be many problems in the process of implementing statistical data in the state of rural economic development, resulting in high or low quality in actual rural economic statistics. Rural economic statistics i... There will be many problems in the process of implementing statistical data in the state of rural economic development, resulting in high or low quality in actual rural economic statistics. Rural economic statistics include a systematic analysis of the positive aspects of the quality of the agricultural and forestry industry and the existing problems. It is also necessary to collect and organize to improve the statistical work system for rural economic development, optimize the economic statistics network system, and the network system. Construction and other aspects to do in-depth discussion. At the same time, strengthen the comprehensive reform of the economic system through data, comprehensively innovate the introduction of talents in agricultural technology, and strengthen the emphasis, reorganization and system optimization of economic management. Conduct systematic analysis of statistical data and use data to guide agricultural development. The article uses statistical mathematics to analyze the optimization and statistical strategies in agricultural economic management under the new rural construction environment. 展开更多
关键词 rural construction economic management optimization strategy statistical system
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The Application of Probability Theory and Mathematical Statistics in Big Data Analysis
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作者 LIU Jijing 《外文科技期刊数据库(文摘版)经济管理》 2021年第6期034-037,共6页
The knowledge of probability is fully reflected in people's daily life and production. People know the world. By using the tools of probability and mathematical statistics, people can scientifically and reasonably... The knowledge of probability is fully reflected in people's daily life and production. People know the world. By using the tools of probability and mathematical statistics, people can scientifically and reasonably analyze various complex problems and data, thus significantly improving people's quality of life. At the same time, they can accurately predict the law and trend of things development based on the existing data. Because of these advantages, probability theory and mathematical statistics have become the direction of many complicated problems. At present, people are in great need of big data analysis. Similarly, people also need a better way for big data analysis to deal with various difficult problems in actual production and life. 展开更多
关键词 probability theory mathematical statistics big data
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Comparative analysis of machine learning and statistical models for cotton yield prediction in major growing districts of Karnataka,India 被引量:1
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作者 THIMMEGOWDA M.N. MANJUNATHA M.H. +4 位作者 LINGARAJ H. SOUMYA D.V. JAYARAMAIAH R. SATHISHA G.S. NAGESHA L. 《Journal of Cotton Research》 2025年第1期40-60,共21页
Background Cotton is one of the most important commercial crops after food crops,especially in countries like India,where it’s grown extensively under rainfed conditions.Because of its usage in multiple industries,su... Background Cotton is one of the most important commercial crops after food crops,especially in countries like India,where it’s grown extensively under rainfed conditions.Because of its usage in multiple industries,such as textile,medicine,and automobile industries,it has greater commercial importance.The crop’s performance is greatly influenced by prevailing weather dynamics.As climate changes,assessing how weather changes affect crop performance is essential.Among various techniques that are available,crop models are the most effective and widely used tools for predicting yields.Results This study compares statistical and machine learning models to assess their ability to predict cotton yield across major producing districts of Karnataka,India,utilizing a long-term dataset spanning from 1990 to 2023 that includes yield and weather factors.The artificial neural networks(ANNs)performed superiorly with acceptable yield deviations ranging within±10%during both vegetative stage(F1)and mid stage(F2)for cotton.The model evaluation metrics such as root mean square error(RMSE),normalized root mean square error(nRMSE),and modelling efficiency(EF)were also within the acceptance limits in most districts.Furthermore,the tested ANN model was used to assess the importance of the dominant weather factors influencing crop yield in each district.Specifically,the use of morning relative humidity as an individual parameter and its interaction with maximum and minimum tempera-ture had a major influence on cotton yield in most of the yield predicted districts.These differences highlighted the differential interactions of weather factors in each district for cotton yield formation,highlighting individual response of each weather factor under different soils and management conditions over the major cotton growing districts of Karnataka.Conclusions Compared with statistical models,machine learning models such as ANNs proved higher efficiency in forecasting the cotton yield due to their ability to consider the interactive effects of weather factors on yield forma-tion at different growth stages.This highlights the best suitability of ANNs for yield forecasting in rainfed conditions and for the study on relative impacts of weather factors on yield.Thus,the study aims to provide valuable insights to support stakeholders in planning effective crop management strategies and formulating relevant policies. 展开更多
关键词 COTTON Machine learning models Statistical models Yield forecast Artificial neural network Weather variables
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Resonance analysis of^(159)Tb(n,γ)reaction based on the CSNS Back-n experiment 被引量:1
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作者 De-Xin Wang Su-Ya-La-Tu Zhang +14 位作者 Wei Jiang Jie Ren Mei-Rong Huang Jing-Yu Tang Xi-Chao Ruan Hong-Wei Wang Long-Xiang Liu Xue Li Dan-Dan Niu Guo Li Gu-Fu Meng Yong-Shun Huang Zhi-Long Wang Yu Bai Xue Yang 《Nuclear Science and Techniques》 2025年第3期85-94,共10页
The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were... The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were performed for the neutron capture cross sections of 159Tb measured at the China Spallation Neutron Source(CSNS)backscattering white neutron beamline(Back-n)facility.The resonance parameters were extracted from the R-Matrix code SAMMY and fitted to the experimental capture yield up to the 1.2 keV resolved resonance region(RRR).The average resonance parameters were determined by performing statistical analysis on the set of the resonance parameters in the RRR.These results were used to fit the measured average capture cross sections using the FITACS code in the unresolved resonance region from 2 keV to 1 MeV.The contributions of partial waves l=0,1,2 to the average capture cross sections are reported. 展开更多
关键词 Statistical analysis Resonance parameters ^(159)Tb(n γ)cross section γ
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Multi-scale damage and fracture analysis and statistical damage constitutive model of shallow coral reef limestone based on digital core 被引量:1
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作者 Yingwei Zhu Xinping Li +4 位作者 Zhengrong Zhou Dengxing Qu Fei Meng Shaohua Hu Wenjie Li 《International Journal of Mining Science and Technology》 2025年第11期1849-1869,共21页
Coral reef limestone(CRL)constitutes a distinctive marine carbonate formation with complex mechanical properties.This study investigates the multiscale damage and fracture mechanisms of CRL through integrated experime... Coral reef limestone(CRL)constitutes a distinctive marine carbonate formation with complex mechanical properties.This study investigates the multiscale damage and fracture mechanisms of CRL through integrated experimental testing,digital core technology,and theoretical modelling.Two CRL types with contrasting mesostructures were characterized across three scales.Macroscopically,CRL-I and CRL-II exhibited mean compressive strengths of 8.46 and 5.17 MPa,respectively.Mesoscopically,CRL-I featured small-scale highly interconnected pores,whilst CRL-II developed larger stratified pores with diminished connectivity.Microscopically,both CRL matrices demonstrated remarkable similarity in mineral composition and mechanical properties.A novel voxel average-based digital core scaling methodology was developed to facilitate numerical simulation of cross-scale damage processes,revealing network-progressive failure in CRL-I versus directional-brittle failure in CRL-II.Furthermore,a damage statistical constitutive model based on digital core technology and mesoscopic homogenisation theory established quantitative relationships between microelement strength distribution and macroscopic mechanical behavior.These findings illuminate the fundamental mechanisms through which mesoscopic structure governs the macroscopic mechanical properties of CRL. 展开更多
关键词 Coral reef limestone Multi-scale mechanics Digital core Pore structure Representative volume element Damage and fracture Damage statistical constitutive model
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An Empirical Analysis of Factors Influencing the Tourism Economy in Henan Province
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作者 Pingping WANG Liang ZHAO 《Asian Agricultural Research》 2025年第11期25-28,共4页
[Objectives]To study the factors influencing the tourism economy in Henan Province.[Methods]Using tourism-related data from Henan Province covering the period from 2000 to 2020,this study constructs a regression model... [Objectives]To study the factors influencing the tourism economy in Henan Province.[Methods]Using tourism-related data from Henan Province covering the period from 2000 to 2020,this study constructs a regression model based on multivariate statistical methods to investigate the determinants of the tourism economy.The dependent variable in the model is the domestic tourism revenue of Henan Province,while the independent variables comprise the number of tourist arrivals,total operational railway mileage,the number of travel agencies,and the per capita disposable income of urban residents.[Results]Both the total railway mileage and the per capita disposable income of urban residents are the primary factors influencing the development of Henan's tourism economy.[Conclusions]It is recommended to reduce uncertainty and liquidity constraints to mitigate residents'precautionary savings behavior,actively expand domestic demand to leverage tourism as an economic driver,and improve infrastructure to support tourism development. 展开更多
关键词 HENAN PROVINCE TOURISM ECONOMY Influencing factors MULTIVARIATE statistical analysis
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