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Inferring Functional Connectivity in fMRI Using Minimum partial correlation

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International Journal of Automation and computing 2017年第4期14卷 371-385页

作者： Lei Nie Xian Yang Paul M. Matthews Zhi-Wei Xu Yi-Ke Guo Department of Computing Imperial College London London SW7 2AZ UK Department of Medicine Imperial College London London SW7 2AZ UK Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China School of Computer Engineering and Science Shanghai University Shanghai 200444 China

Functional connectivity has emerged as a promising approach to study the functional organisation of the brain and to define features for prediction of brain state. The most widely used method for inferring functional connectivity is Pearson＇s correlation, but it cannot differentiate direct and indirect effects. This disadvantage is often avoided by computing the partial correlation between two regions controlling all other regions, but this method suffers from Berkson＇s paradox. Some advanced methods, such as regularised inverse covariance, have been applied. However, these methods usually depend on some parameters. Here we propose use of minimum partial correlation as a parameter-free measure for the skeleton of functional connectivity in functional magnetic resonance imaging （flVIRI）. The minimum partial correlation between two regions is the minimum of absolute values of partial correlations by controlling all possible subsets of other regions. Theoretically, there is a direct effect between two regions if and only if their minimum partial correlation is non-zero under faithfulness and Gaussian assumptions. The elastic PC-algorithm is designed to efficiently approximate minimum partial correlation within a computational time budget. The simulation study shows that the proposed method outperforms others in most cases and its application is illustrated using a resting-state fMRI dataset from the human connectome project.

关键词： Functional connectivity functional magnetic resonance imaging (fMRI) network modelling partial correlation PC-algorithm resting-state networks.

Generalized bounds on the partial periodic correlation of complex roots of unity sequence set

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 207-210页

作者： Li-fang FENG Institute of Mobile Communication Southwest Jiaotong University Chengdu 610031 China

In this paper,the generalized bounds are derived on the partial periodic correlation of complex roots of unity sequence set with zero or low correlation zone(ZCZ/LCZ)as the important criteria of the sequence design and *** derived bounds are with respect to family size,subsequence length,maximum partial autocorrelation sidelobe,maximum partial cross-correlation value and the ZCZ/*** results show that the derived bounds include the previous periodic bounds,such as Sarwate bound,Welch bound,Peng-Fan bound and Paterson-Lothian bound,as special cases.

关键词： partial correlation Zero correlation zone (ZCZ) Low correlation zone (LCZ) CDMA

CHANGES OF PAN EVAPORATION IN THE UPPER REACH OF THE YANGTZE RIVER

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Journal of Hydrodynamics 2011年第4期23卷 503-509页

作者： RONG Yan-shu WANG Wen JIANG Hai-yan College of Hydrology and Water Resources Hohai University Nanjing 210098 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China

The upper reach of the Yangtze River, 4 511 km long from west to east, contains a great amount of water resources of the Yangtze River Basin. This article studies the characteristics of the pan evaporation, the related meteorological variables, and their effects on the pan evaporation, based on the data of the daily pan evaporation （1980-2008） and other meteorological variables （1961-2008）. The results show that the linear trend of the pan evaporation has remarkable regional features, i.e., the decrease trend in the southwest and the increase trend in the northeast of the investigated region, and the Yangtze River is approximately the boundary of these trends. The meteorological variables have different effects on the pan evaporation depending on the fact that they are in the category the thermal variables or the dynamic variables. The thermal meteorological variables （i.e., air temperature, diurnal temperature range, and sunshine duration） have positive partial correlations with the pan evaporation, while the dynamic ones （air pressure, rainfall, and relateive humidity） have negative correlations with the pan evaporation. The correlation of the wind speed remains to be investigated.

关键词： linear time trend meteorological variable pan evaporation partial correlation Yangtze River

A coarse-to-fine image registration method based on visual attention model

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Science China(Information Sciences) 2014年第12期57卷 122-131页

作者： FENG Jing MA Long BI FuKun ZHANG XueJing CHEN He School of Information and Electronics Beijing Institute of Technology College of Information Engineering North China University of Technology College of Information Technology Beijing Union University

Image registration is fundamental and crucial to remote *** getting highly accurate registration performance automatically and fast for large-field images consistently is a *** a work around to this problem,we propose a new image registration concept based on visual attention in this *** concept employs the advantages of feature-based or area-based methods to improve the precision and efficiency of image *** key concept of proposed integrated scheme is to make optimum use of the highly prominent details in the full scene by means of visual attention computational *** testify the validation,comparisons with other classical methods are carried out on real-world *** experimental results show that the proposed method can effectively perform on multi-view/multi-temporal remote sensing images with outstanding precision and time saving performance.

关键词： remote sensing image registration visual attention similarity measure partial correlation coarseto-fine process

Multi-Purpose Forensics of Image Manipulations Using Residual-Based Feature

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Computers, Materials & Continua 2020年第12期65卷 2217-2231页

作者： Anjie Peng Kang Deng Shenghai Luo Hui Zeng Southwest University of Science and Technology Mianyang621010China Binghamton University State University of New YorkNewYork13902USA

The multi-purpose forensics is an important tool for forge image *** this paper,we propose a universal feature set for the multi-purpose forensics which is capable of simultaneously identifying several typical image manipulations,including spatial low-pass Gaussian blurring,median filtering,re-sampling,and JPEG *** eliminate the influences caused by diverse image contents on the effectiveness and robustness of the feature,a residual group which contains several high-pass filtered residuals is *** partial correlation coefficient is exploited from the residual group to purely measure neighborhood correlations in a linear *** that,we also combine autoregressive coefficient and transition probability to form the proposed composite feature which is used to measure how manipulations change the neighborhood relationships in both linear and non-linear *** a series of dimension reductions,the proposed feature set can accelerate the training and testing for the multi-purpose *** proposed feature set is then fed into a multi-classifier to train a multi-purpose *** results show that the proposed detector can identify several typical image manipulations,and is superior to the complicated deep CNN-based methods in terms of detection accuracy and time efficiency for JPEG compressed image with low resolution.

关键词： Digital image forensics partial correlation auto-regression multi-classification

Statistical downscaling model for late-winter rainfall over Southwest China

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Science China Earth Sciences 2015年第7期58卷 1827-1839页

作者： RUAN ChengQing LI JianPing FENG Juan State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences College of Earth Sciences University of Chinese Academy of Sciences College of Global Change and Earth System Science Beijing Normal University Joint Center for Global Change Studies

A statistical downscaling model is built for the late-winter rainfall over Southwest China(SWC).A partial-correlation method is used for selecting *** results show that the selected factors for late-winter rainfall in SWC are sea level pressure in Western Europe(SNAO)and sea surface temperature in Western Pacific(WPT).SNAO is related to the southern pole of North Atlantic Oscillation(NAO)and excites Southern Eurasian teleconnection,which influences the development of the southern branch trough and the water vapor transport to *** indicates the variability of ENSO in the tropical Western *** excites Pacific-East Asia teleconnection and an anticyclone(cyclone)is formed in the southern part of China and suppresses(enhances)rainfall over SWC.A regression statistical downscaling model using SNAO and WPT shows good performance in fitting the variability of late-winter rainfall in the whole SWC region and every observation station,and the model also shows strong robustness in the independent *** statistical model can be used for downscaling output from seasonal forecast numerical models and improve the SWC late winter rainfall prediction in the future.

关键词： statistical downscaling Southwest China late-winter rainfall partial correlation

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An Analysis of the correlation between the Economic Barometer and the Postal Service

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The Journal of China Universities of Posts and Telecommunications 2002年第3期9卷 74-78页

作者： LIU Hong wei, XUE Feng min, LI Xue dong (Shijiazhuang Postal College, Shijiazhuang 050021, P.R. China) Shijiazhuang Postal College Shijiazhuang 050021 P.R. China

There are many economic factors that can influence the postal market. In thispaper, by adopting the method of quantitative analysis, the author analyse exhaustively theeconomic factors that influence the postal market... 详细信息

关键词： economic factors postal market partial correlation