Results 71 to 80 of about 234,460 (307)

Fractional integration and cointegration in US financial time series data [PDF]

, 2011
This paper examines several US monthly financial time series data using fractional integration and cointegration techniques. The univariate analysis based on fractional integration aims to determine whether the series are I(1) (in which case markets ...
Gil-Alana, Luis A., Luis A. Gil-Alana, Guglielmo Maria Caporale, Caporale, GM, Caporale, Guglielmo Maria, Gil-Alana, LA   +5 more
core   +2 more sources

Sustainable Electrochemical Synthesis of High‐Quality MXenes: Mechanistic Insights, Applications, Challenges, and Technological Prospects

Advanced Functional Materials, EarlyView.
Electrochemical etching provides an eco‐friendly alternative to hazardous HF methods for MXene production. This approach facilitates the selective isolation of the A‐layer from MAX phases with tunable surface terminations. Controlling voltage, electrolytes, temperature, and duration enables the optimal structural integrity. Nevertheless, existing scale
Jagdeep Singh, Madhusudhana M Devadiga, Santosh K. Tiwari, AS Dhaliwal, Gurpreet Singh Selopal   +4 more
wiley   +1 more source

Forecasting Multivariate Time Series with the Theta Method [PDF]

Journal of Forecasting, 2015
AbstractIn this study building on earlier work on the properties and performance of the univariate Theta method for a unit root data‐generating process we: (a) derive new theoretical formulations for the application of the method on multivariate time series; (b) investigate the conditions for which the multivariate Theta method is expected to forecast ...
Dimitrios D. Thomakos, Konstantinos Nikolopoulos   +1 more
openaire   +1 more source

Estimating factor models for multivariate volatilities : an innovation expansion method [PDF]

, 2010
We introduce an innovation expansion method for estimation of factor models for conditional variance (volatility) of a multivariate time series. We estimate the factor loading space and the number of factors by a stepwise optimization algorithm on ...
Qiwei Yao, Yao, Qiwei, Polonik, Wolfgang, Wolfgang Polonik, Pan, Jiazhu, Jiazhu Pan   +5 more
core   +1 more source

Beyond Presumptions: Toward Mechanistic Clarity in Metal‐Free Carbon Catalysts for Electrochemical H2O2 Production via Data Science

Advanced Materials, EarlyView.
Metal‐free carbon catalysts enable the sustainable synthesis of hydrogen peroxide via two‐electron oxygen reduction; however, active site complexity continues to hinder reliable interpretation. This review critiques correlation‐based approaches and highlights the importance of orthogonal experimental designs, standardized catalyst passports ...
Dayu Zhu, Hsi‐wen Wu, Xiao Wang, Jie Zhang   +3 more
wiley   +1 more source

Resistance to Overdoping Allows Over 2000 S cm−1 Conductivity in P(g3BTTT) With Anion‐Exchange Doping

Advanced Materials, EarlyView.
Anion‐exchange doping of conjugated polymers is an effective way to achieve high conductivities. Here, we report over 2000 S cm−1 electrical conductivity for doped P(g3BTTT). In addition, we show that P(g3BTTT) sustains exceptionally high doping levels without any drop in the charge mobility.
Basil Hunger, Maximilian M. Horn, Eva Röck, Diego Rosas Villalva, Lize Bynens, Jochen Vanderspikken, Christina Kousseff, Silène Gobeil, Olivier Bardagot, Nesibe Akmanşen‐Kalayci, Sarah H. Tolbert, Iain McCulloch, Wouter Maes, Demetra Tsokkou, Natalie Banerji   +14 more
wiley   +1 more source

End‐to‐End Sensing Systems for Breast Cancer: From Wearables for Early Detection to Lab‐Based Diagnosis Chips

Advanced Materials Technologies, EarlyView.
This review explores advances in wearable and lab‐on‐chip technologies for breast cancer detection. Covering tactile, thermal, ultrasound, microwave, electrical impedance tomography, electrochemical, microelectromechanical, and optical systems, it highlights innovations in flexible electronics, nanomaterials, and machine learning.
Neshika Wijewardhane, Lyn I. Jones, Richard M. Martin, Helen Winter, Faezeh Arab Hassani   +4 more
wiley   +1 more source

Robust exponential smoothing of multivariate time series. [PDF]

Multivariate time series may contain outliers of different types. In presence of such outliers, applying standard multivariate time series techniques becomes unreliable. A robust version of multivariate exponential smoothing is proposed.
Croux, Christophe, Gelper, Sarah, Mahieu, Koen   +2 more
core  

Turning Water Into a Tool: From Degradation Pathways to Functional Engineering in Halide Perovskites

Advanced Materials Technologies, EarlyView.
Water exhibits a threshold‐dependent dual role in lead halide perovskites, acting either as a degradation trigger or as a powerful tool for defect passivation, recrystallization, and structural engineering. This review discusses how controlled water‐mediated interactions govern stability, dimensionality, and optoelectronic performance, providing ...
Raphaella T. S. Gonçalves, Gabriela O. Gera, Aryane Tofanello, Jose A. Souza, Andre L. M. Freitas   +4 more
wiley   +1 more source

Data Augmentation with Suboptimal Warping for Time-Series Classification

Sensors, 2019
In this paper, a novel data augmentation method for time-series classification is proposed. In the introduced method, a new time-series is obtained in warped space between suboptimally aligned input examples of different lengths.
Krzysztof Kamycki, Tomasz Kapuscinski, Mariusz Oszust   +2 more
doaj   +1 more source