Results 61 to 70 of about 7,174 (250)

Exchange Rates and Sovereign Risk: A Nonlinear Approach Based on Local Gaussian Correlations

International Journal of Finance &Economics, EarlyView.
ABSTRACT We empirically assess the interlinkages between sovereign risk, measured in terms of CDS spreads, and exchange rates for a sample of emerging markets. Our period of analysis includes episodes of severe stress, such as the Global Financial Crisis, the COVID‐19 pandemic, and the Ukrainian War.
Reinhold Heinlein, Gabriella D. Legrenzi, Scott M. R. Mahadeo   +2 more
wiley   +1 more source

Stretched non-negative matrix factorization

npj Computational Materials
A novel algorithm, stretchedNMF, is introduced for non-negative matrix factorization (NMF), accounting for signal stretching along the independent variable’s axis.
Ran Gu, Yevgeny Rakita, Ling Lan, Zach Thatcher, Gabrielle E. Kamm, Daniel O’Nolan, Brennan Mcbride, Allison Wustrow, James R. Neilson, Karena W. Chapman, Qiang Du, Simon J. L. Billinge   +11 more
doaj   +1 more source

Sparsity-Constrained Coupled Nonnegative Matrix–Tensor Factorization for Hyperspectral Unmixing

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2020
Hyperspectral unmixing refers to a source separation problem of decomposing a hyperspectral imagery (HSI) to estimate endmembers, and their corresponding abundances.
Heng-Chao Li, Shuang Liu, Xin-Ru Feng, Shao-Quan Zhang   +3 more
doaj   +1 more source

Multiobjective Simulation–Optimization of Crop Allocation and Water Resources in Canal Command Areas Using Genetic Algorithms

Irrigation and Drainage, EarlyView.
ABSTRACT This study develops an integrated simulation–optimization framework for sustainable crop allocation and water resource management in the Bargarh Canal Command (BCC), eastern India. Efficient irrigation allocation remains a critical challenge due to competing demands, groundwater–surface water interactions and environmental constraints ...
Priyanka Mohapatra, J. C. Paul, Sushree Sangita Dash   +2 more
wiley   +1 more source

Heuristics for exact nonnegative matrix factorization [PDF]

, 2015
The exact nonnegative matrix factorization (exact NMF) problem is the following: given an m-by-n nonnegative matrix X and a factorization rank r, find, if possible, an m-by-r nonnegative matrix W and an r-by-n nonnegative matrix H such that X=WH. In this
Vandaele, Arnaud, Glineur, François, Tuyttens, Daniel, Gillis, Nicolas   +3 more
core   +1 more source

Efficient First‐Principles Inverse Design of Nanolasers

Laser &Photonics Reviews, EarlyView.
This article introduces a first‐principles inverse‐design framework for nanolasers that directly incorporates nonlinear lasing physics. By unifying steady‐state ab‐initio laser theory (SALT) with topology optimization, it reveals how spatial hole burning, gain saturation, and cavity‐emitter coupling shape laser performance, enabling efficient discovery
Beñat Martinez de Aguirre Jokisch, Alexander Cerjan, Rasmus Ellebæk Christiansen, Jesper Mørk, Ole Sigmund, Steven G. Johnson   +5 more
wiley   +1 more source

Nonparametric bayesian nonnegative matrix factorization

, 2021
© Springer Nature Switzerland AG 2020. Nonnegative Matrix Factorization (NMF) is an important tool in machine learning for blind source separation and latent factor extraction.
Mengersen, K, Xie, HB, Xu, RYD, Li, C, Wang, S   +4 more
core   +1 more source

A highly accurate numerical method for solving boundary value problem of generalized Bagley‐Torvik equation

Mathematical Methods in the Applied Sciences, EarlyView.
A highly accurate numerical method is given for the solution of boundary value problem of generalized Bagley‐Torvik (BgT) equation with Caputo derivative of order 0<β<2$$ 0<\beta <2 $$ by using the collocation‐shooting method (C‐SM). The collocation solution is constructed in the space Sm+1(1)$$ {S}_{m+1}^{(1)} $$ as piecewise polynomials of degree at ...
Suzan Cival Buranay, Mtema James Chin, Nazim I. Mahmudov   +2 more
wiley   +1 more source

Hybridizing sparse component analysis with genetic algorithms for microarray analysis

, 2008
Nonnegative matrix factorization (NMF) has proven to be a useful tool for the analysis of nonnegative multivariate data. However, it is known not to lead to unique results when applied to blind source separation (BSS) problems.
Stadlthanner, K., Puntonet, C. G., Stadlthanner, Kurt, Lang, Elmar, Lang, E. W., Puntonet, Carlos G., Górriz, J. M., Tomé, A. M., Theis, Fabian J., Theis, F. J.   +9 more
core   +1 more source

High Relative Accuracy Computations With Covariance Matrices of Order Statistics

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT In many statistical applications, numerical computations with covariance matrices need to be performed. The error made when performing such numerical computations increases with the condition number of the covariance matrix, which is related to the number of variables and the strength of the correlation between the variables. In a recent work,
Juan Baz, Pedro Alonso, Juan Manuel Peña, Raúl Pérez‐Fernández   +3 more
wiley   +1 more source