This study proposes a numerical scheme employing quadratic and cubic B-spline finite element methods (FEM) for solving nonlinear diffusion equations. For time discretization, a finite difference method is applied, whi...
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The coupled dipole method, as originally formulated by Purcell and Pennypacker [3], is a very powerful method to simulate the elastic light scattering from arbitrary particles. This method, however, has one major draw...
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The coupled dipole method, as originally formulated by Purcell and Pennypacker [3], is a very powerful method to simulate the elastic light scattering from arbitrary particles. This method, however, has one major drawback: if the size of the particles grows, or if scattering from an ensemble of randomly oriented particles has to be simulated, the computational demands of the coupled dipole method soon become too high. This paper presents two new computational techniques to resolve this problem. First the coupled dipole method was implemented on a massively parallel computer. The parallel efficiency can be very close to 1, implying that the attained computational speed scales perfectly with the number of processors. Second, it is proposed to reduce the computational complexity of the coupled dipole method by including ideas from the so-called fast multipole methods (hierarchical algorithms) into the coupled dipole method. In this way the calculation time can be decreased by orders of magnitude.
Carotid artery stenosis (CAS) reduces cerebral perfusion, which can contribute to neurodegeneration and cognitive decline. While fMRI studies have identified CAS-related disruptions in functional connectivity (FC) ass...
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Carotid artery stenosis (CAS) reduces cerebral perfusion, which can contribute to neurodegeneration and cognitive decline. While fMRI studies have identified CAS-related disruptions in functional connectivity (FC) associated with neurodegeneration, translating these methods to functional near-infrared spectroscopy (fNIRS) offers a portable, clinically practical alternative. In this study, we assessed FC using fNIRS in 44 CAS patients and 20 controls during breath-holding, a clinical vasoreactivity task. Our results demonstrate clear differences between FC during breath-holding and the resting state, highlighting the task's impact on network connectivity. Patients with unilateral mild stenosis (50–69 % occlusion) exhibited FC patterns comparable to those of controls, whereas patients with bilateral severe stenosis showed a 26 % reduced connectivity and a 14 % lower clustering. When accounting for time delays of 0.9–1.3 seconds, network synchrony was restored across all CAS groups, suggesting that the proposed fNIRS-based method can be used to investigate compensatory hemodynamic delays in CAS. Although sample size limits broader clinical generalizations, this work demonstrates the feasibility of using fNIRS for FC analysis in CAS during a vasodilatory task and provides evidence that fNIRS-based FC metrics are sensitive to CAS severity.
Security is a vital parameter to conserve energy in wireless sensor networks(WSN).Trust management in the WSN is a crucial process as trust is utilized when collaboration is important for accomplishing trustworthy dat...
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Security is a vital parameter to conserve energy in wireless sensor networks(WSN).Trust management in the WSN is a crucial process as trust is utilized when collaboration is important for accomplishing trustworthy data *** the available routing techniques do not involve security in the design of routing *** study develops a novel statistical analysis with dingo optimizer enabled reliable routing scheme(SADO-RRS)for *** proposed SADO-RRS technique aims to detect the existence of attacks and optimal routes in *** addition,the presented SADORRS technique derives a new statistics based linear discriminant analysis(LDA)for attack detection,Moreover,a trust based dingo optimizer(TBDO)algorithm is applied for optimal route selection in the WSN and accomplishes secure data transmission in ***,the TBDO algorithm involves the derivation of the fitness function involving different input variables of *** demonstrating the enhanced outcomes of the SADO-RRS technique,a wide range of simulations was carried out and the outcomes demonstrated the enhanced outcomes of the SADO-RRS technique.
The main target of this paper is presentation of an efficient method for MRI images classification so that it can be used to diagnose patients and *** classification is one of the prominent subset topics of machine le...
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The main target of this paper is presentation of an efficient method for MRI images classification so that it can be used to diagnose patients and *** classification is one of the prominent subset topics of machine learning and data mining that the most important image technique is the auto-categorization of *** images with high resolution and appropriate accuracy allow physicians to decide on the diagnosis of various diseases and treat *** auto categorization of MRI images toward diagnosing brain diseases has been being used to accurately diagnose hospitals,clinics,physicians and medical research *** this paper,an effective method is proposed for categorizing MRI images,which emphasizes the classification *** this method,images have been firstly collected and tagged,and then the discrete wavelet transform method has been implemented to extract the relevant *** the ready features in a matrix will be subsequently held,and PCA method has been applied to reduce the features ***,a new model using support vector machine classifier with radial basis function kernel ***+RBF has been *** SVM Algorithm must bimanually initialized,while,these values have been automatically entered into the SVM classifier by Salp Swarm Algorithm(SSA):Due to high performance of SSA in fast and accurate solution of nonlinear problem as compared to other optimization algorithms,it has been applied to optimally solve the designed ***,after applying the optimal parameters and SVM classification training,the test data has been utilized and *** results have transparently suggested the effectiveness of the proposed method in the Accuracy criteria with 0.9833,the Sensitivity with 1,Specificity with 0.9818 and Error with 0.0167 in best iteration as compared to the conventional SVM method.
An integer sequence (d) = (d1, d2,..., d(n)) is graphic if there is a graph whose degree sequence is (d). A graph G is maximal if its degree sequence is majorized by no other graphic sequence. The Laplacian matrix of ...
An integer sequence (d) = (d1, d2,..., d(n)) is graphic if there is a graph whose degree sequence is (d). A graph G is maximal if its degree sequence is majorized by no other graphic sequence. The Laplacian matrix of G is L(G) = D(G) - A(G), where D(G) is the diagonal matrix of vertex degrees and A(G) is the (0, 1) adjacency matrix. The article contains an explicit (algorithmic) construction of all maximal graphs, from which it follows, e.g., that, apart from 0, the Laplacian spectrum of a maximal graph is the conjugate of its degree sequence.
The multiple-scale expansion is used to derive averaged Equations governing the slow evolution of a pulse in a randomly birefringent, non-polarization-preserving fiber. It is shown that, in the limit when the average ...
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The multiple-scale expansion is used to derive averaged Equations governing the slow evolution of a pulse in a randomly birefringent, non-polarization-preserving fiber. It is shown that, in the limit when the average beat length is much less than the correlation length of random variations of the fiber's parameters, these equations are two nonlinearly coupled nonlinear Schrodinger equations, with the cross-coupling coefficient being, in general, different from 1. The effect of perturbations of the averaged equations that result from randomness of the fiber parameters is estimated. (C) 1996 Optical Society of America.
It has been shown that some non-regular context-free languages can be recognized by two-way probabilistic finite state automata (2pfa's) and some context-free languages cannot be recognized by any 2pfa. It is easy...
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It has been shown that some non-regular context-free languages can be recognized by two-way probabilistic finite state automata (2pfa's) and some context-free languages cannot be recognized by any 2pfa. It is easy to show that 2pfa's can even recognize some non-context-free context-sensitive languages. We prove in this note that the class of all languages recognized by 2pfa's is strictly included in the class of all deterministic context-sensitive languages.
Consider the domain of multiclass classification within the adversarial online setting. What is the price of relying on bandit feedback as opposed to full information? To what extent can an adaptive adversary amplify ...
We demonstrate efficient on-chip green light generation via frequency upconversion in silicon nitride–thin-film lithium niobate (SiN-TFLN) hybrid waveguides, obtained by transfer printing LN coupons on selected areas...
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