Results 91 to 100 of about 29,735 (296)

Long memory and volatility dynamics in the US Dollar exchange rate [PDF]

, 2010
This paper focuses on nominal exchange rates, specifically the US dollar rate vis-à-vis the Euro and the Japanese Yen at a daily frequency. We model both absolute values of returns and squared returns using long-memory techniques, being particularly ...
Gil-Alana, Luis A., Caporale, GM, Caporale, Guglielmo Maria, Gil-Alana, LA   +3 more
core  

Workflow for Design of Experiments‐Based Modeling of Species Transport and Growth Kinetics in GaN Hydride Vapor Phase Epitaxy

Advanced Engineering Materials, EarlyView.
A novel workflow for investigating hydride vapor phase epitaxy for GaN bulk crystal growth is proposed. It combines Design of experiments (DoE) with physical simulations of mass transport and crystal growth kinetics, serving as an intermediate step between DoE and experiments.
J. Tomkovič, G. Lukin, H. Torkashvand, A. Kerschbaum, M. Müller, S. Besendörfer, J. Heitmann, J. Friedrich   +7 more
wiley   +1 more source

Approximations for Fractional Derivatives and Fractional Integrals Using Padé Approximation

Journal of Applied Mathematics
This paper tackles the persistent challenge of slow convergence and numerical instability in the fractional calculus when applied to power series–representable functions fx=∑i=0∞cixi, limitations that compromise accuracy in scientific applications.
Ahmed M. Youssef, Tamer M. Rageh, Aisha F. Fareed, M. S. Abdelwahed   +3 more
doaj   +1 more source

Time fractional Kupershmidt equation: symmetry analysis and explicit series solution with convergence analysis [PDF]

, 2019
summary:In this work, the fractional Lie symmetry method is applied for symmetry analysis of time fractional Kupershmidt equation. Using the Lie symmetry method, the symmetry generators for time fractional Kupershmidt equation are obtained with Riemann ...
Chauhan, Astha, Arora, Rajan
core   +1 more source

Experimental Characterization and Constitutive Modeling of the Effect of Prior Inelastic Strain on the Viscoplastic Behavior of AD730 at 700 °C

Advanced Engineering Materials, EarlyView.
This study shows that superalloys used in aircraft engine disks become much more prone to deformation at high temperatures if they have been strained during manufacturing. This effect increases with the level of prior strain but eventually reaches a limit.
Fabio Machado Alves da Fonseca, Patrick Villechaise, Malik Durand, Arnaud Longuet, Florent Coudon, Loïc Signor, Julien De Jaeger, Dominique Eyidi, Nathalie Bozzolo, Jonathan Cormier   +9 more
wiley   +1 more source

A Dislocation Perspective on Strength and Toughness in Ceramics

Advanced Engineering Materials, EarlyView.
Dislocations in ceramics enjoy a long but yet under‐appreciated history. The three research waves for dislocations in ceramics highlight the topic evolution over the last 90 years. This review focuses on the impact of dislocation on strength and toughness in ceramics.
Xufei Fang
wiley   +1 more source

Machine Learning‐Supported Analysis for Predicting and Visualizing Nonlinear Relationships Between Material Properties in Electroplated Chromium Layers

Advanced Engineering Materials, EarlyView.
This study applies machine learning regression to predict chromium layer thickness in decorative trivalent chromium electroplating, using 441 experiments from laboratory‐scale (1L) and pilot‐scale (14L) setups. Tree‐based models, particularly CatBoost, outperformed linear regression by capturing nonlinear parameter interactions (R2$R^2$ up to 0.77 ...
Christoph Baumer, Christopher Mai, Luca Eisentraut, Andreas Bund, Ricardo Buettner   +4 more
wiley   +1 more source

Numerical investigation of a fractional model of a tumor-immune surveillance via Caputo operator

Alexandria Engineering Journal
Fractional calculus has become a potent tool for simulating the complexity of interactions in tumor-immune system dynamics. This paper investigates the existence and uniqueness of its approximation solutions of a fractional model of tumor-immune ...
Saleh Alshammari, Mohammad Alshammari, Mohammed Alabedalhadi, M. Mossa Al-Sawalha, Mohammed Al-Smadi   +4 more
doaj   +1 more source

Approximate Analytical Solution for a Coupled System of Fractional Nonlinear Integrodifferential Equations by the RPS Method

Complexity, 2020
In this work, a modified residual power series method is implemented for providing efficient analytical and approximate solutions for a class of coupled system of nonlinear fractional integrodifferential equations.
Ayed Al e’damat
doaj   +1 more source

REAL EXCHANGE RATES IN LATIN AMERICA: THE PPP HYPOTHESIS AND FRACTIONAL INTEGRATION [PDF]

This paper tests for PPP in a group of seventeen Latin American (LA) countries by applying fractional integration techniques to real exchange rate series. Compared to earlier studies on these economies, this approach has the advantage of allowing for non-
Luis A. Gil-Alana, Guglielmo Maria Caporale   +1 more
core