Journal of Applied Mathematics最新文献_第8页

Journal of Applied Mathematics Pub Date : 2013-08-01 DOI: 10.1155/2013/309392

Areej M. Abduldaim, Sheng Chen

引用次数: 6

Effective Preprocessing Procedures Virtually Eliminate Distance-Dependent Motion Artifacts in Resting State FMRI. 有效的预处理程序实际上消除了静息状态FMRI中与距离相关的运动伪影。

Journal of Applied Mathematics Pub Date : 2013-05-21 DOI: 10.1155/2013/935154

Hang Joon Jo, Stephen J Gotts, Richard C Reynolds, Peter A Bandettini, Alex Martin, Robert W Cox, Ziad S Saad

{"title":"Effective Preprocessing Procedures Virtually Eliminate Distance-Dependent Motion Artifacts in Resting State FMRI.","authors":"Hang Joon Jo, Stephen J Gotts, Richard C Reynolds, Peter A Bandettini, Alex Martin, Robert W Cox, Ziad S Saad","doi":"10.1155/2013/935154","DOIUrl":"https://doi.org/10.1155/2013/935154","url":null,"abstract":"Artifactual sources of resting-state (RS) FMRI can originate from head motion, physiology, and hardware. Of these sources, motion has received considerable attention and was found to induce corrupting effects by differentially biasing correlations between regions depending on their distance. Numerous corrective approaches have relied on the identification and censoring of high-motion time points and the use of the brain-wide average time series as a nuisance regressor to which the data are orthogonalized (Global Signal Regression, GSReg). We first replicate the previously reported head-motion bias on correlation coefficients using data generously contributed by Power et al. (2012). We then show that while motion can be the source of artifact in correlations, the distance-dependent bias-taken to be a manifestation of the motion effect on correlation-is exacerbated by the use of GSReg. Put differently, correlation estimates obtained after GSReg are more susceptible to the presence of motion and by extension to the levels of censoring. More generally, the effect of motion on correlation estimates depends on the preprocessing steps leading to the correlation estimate, with certain approaches performing markedly worse than others. For this purpose, we consider various models for RS FMRI preprocessing and show that WMeLOCAL, as subset of the ANATICOR discussed by Jo et al. (2010), denoising approach results in minimal sensitivity to motion and reduces by extension the dependence of correlation results on censoring.","PeriodicalId":49251,"journal":{"name":"Journal of Applied Mathematics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2013/935154","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32021708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 258

Splitting Matching Pursuit Method for Reconstructing Sparse Signal in Compressed Sensing 压缩感知中稀疏信号重构的分割匹配追踪方法

Journal of Applied Mathematics Pub Date : 2013-05-12 DOI: 10.1155/2013/804640

L. Jing, Chong-Zhao Han, Xianghua Yao, Lian Feng

{"title":"Splitting Matching Pursuit Method for Reconstructing Sparse Signal in Compressed Sensing","authors":"L. Jing, Chong-Zhao Han, Xianghua Yao, Lian Feng","doi":"10.1155/2013/804640","DOIUrl":"https://doi.org/10.1155/2013/804640","url":null,"abstract":"In this paper, a novel method named as splitting matching pursuit (SMP) is proposed to reconstruct -sparse \u0000signal in compressed sensing. The proposed method selects largest components of the correlation \u0000vector , which are divided into split sets with equal length . The searching area is thus expanded to incorporate \u0000more candidate components, which increases the probability of finding the true components at one iteration. The \u0000proposed method does not require the sparsity level to be known in prior. The Merging, Estimation and Pruning \u0000steps are carried out for each split set independently, which makes it especially suitable for parallel computation. The \u0000proposed SMP method is then extended to more practical condition, e.g. the direction of arrival (DOA) estimation \u0000problem in phased array radar system using compressed sensing. Numerical simulations show that the proposed \u0000method succeeds in identifying multiple targets in a sparse radar scene, outperforming other OMP-type methods. \u0000The proposed method also obtains more precise estimation of DOA angle using one snapshot compared with the \u0000traditional estimation methods such as Capon, APES (amplitude and phase estimation) and GLRT (generalized \u0000likelihood ratio test) based on hundreds of snapshots.","PeriodicalId":49251,"journal":{"name":"Journal of Applied Mathematics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2013/804640","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64260980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

On a Level-Set Method for Ill-Posed Problems with Piecewise Nonconstant Coefficients 分段非常系数不适定问题的水平集方法

Journal of Applied Mathematics Pub Date : 2013-01-31 DOI: 10.1155/2013/123643

A. Cezaro

引用次数: 1

(m,n)-Semirings and a Generalized Fault-Tolerance Algebra of Systems (m,n)-半环与系统的广义容错代数

Journal of Applied Mathematics Pub Date : 2013-01-01 DOI: 10.1155/2013/482391

Syed Eqbal Alam, Shrisha Rao, B. Davvaz

引用次数: 7

Metric Subregularity for Subsmooth Generalized Constraint Equations in Banach Spaces Banach空间中次光滑广义约束方程的度量子正则性

Journal of Applied Mathematics Pub Date : 2012-12-26 DOI: 10.1155/2012/185249

Qinghai He, Ji Yang, Binbin Zhang

引用次数: 2

Stability of the Stochastic Reaction-Diffusion Neural Network with Time-Varying Delays and p-Laplacian 时变时滞随机反应-扩散神经网络的稳定性和p- laplace

Journal of Applied Mathematics Pub Date : 2012-12-03 DOI: 10.1155/2012/405939

Pan Qingfei, Zhang Zi-fang, Huang Jingchang

引用次数: 8

Approximate Super- and Sub-harmonic Response of a Multi-DOFs System with Local Cubic Nonlinearities under Resonance 具有局部三次非线性的多自由度系统在共振下的近似超谐波和次谐波响应

Journal of Applied Mathematics Pub Date : 2012-11-10 DOI: 10.1155/2012/531480

Yang Caijin

{"title":"Approximate Super- and Sub-harmonic Response of a Multi-DOFs System with Local Cubic Nonlinearities under Resonance","authors":"Yang Caijin","doi":"10.1155/2012/531480","DOIUrl":"https://doi.org/10.1155/2012/531480","url":null,"abstract":"A multi-degree-of-freedom dynamical system with local cubic nonlinearities subjected to super/subharmonic excitation is considered in this paper. The purpose of this paper is to approximate the \u0000nonlinear response of system at super/sub harmonic resonance. For many situations, single resonance mode is often observed to be leading as system enters into super/sub harmonic resonance. In this case, the single modal natural resonance theory can be applied to reduce the system model and a simplified model with only a single DOF is always obtained. Thus, an approximate solution and the analytical expression of frequency response relation are then derived using classical perturbation analysis. While the system is controlled by multiple modes, modal analysis for linearized system is used to decide dominant modes. The reduced model governed by these relevant modes is found and results in an approximate numerical solutions. An illustrative example of the discrete mass-spring-damper nonlinear vibration system with ten DOFs is examined. The approximation results are validated by comparing them with the calculations from direct numerical integration of the equation of motion of the original nonlinear system. Comparably good agreements are obtained.","PeriodicalId":49251,"journal":{"name":"Journal of Applied Mathematics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/531480","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64330104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

The Global Convergence of a New Mixed Conjugate Gradient Method for Unconstrained Optimization 一种新的无约束优化混合共轭梯度法的全局收敛性

Journal of Applied Mathematics Pub Date : 2012-10-16 DOI: 10.1155/2012/932980

Yang Yueting, Cao Mingyuan

引用次数: 3

Symbolic Computation and the Extended Hyperbolic Function Method for Constructing Exact Traveling Solutions of Nonlinear PDEs 构造非线性偏微分方程精确运动解的符号计算和扩展双曲函数法

Journal of Applied Mathematics Pub Date : 2012-10-11 DOI: 10.1155/2012/716719

Huang Yong, Shang Yadong, Yu Wenjun

引用次数: 2