Results 61 to 70 of about 80,517 (261)

Mixed‐Metal Promotion in a Manganese‐Molybdenum Oxynitride as Catalyst to Integrate C─C and C─N Coupling Reactions for the Direct Synthesis of Acetonitrile from Syngas and Ammonia

Advanced Materials, EarlyView.
Transition metal oxy/carbo‐nitrides show great promise as catalysts for sustainable processes. A Mn‐Mo mixed‐metal oxynitride attains remarkable performance for the direct synthesis of acetonitrile, an important commodity chemical, via sequential C─N and C─C coupling from syngas (C1) and ammonia (N1) feedstocks.
M. Elena Martínez‐Monje, Wilson Henao, Tania Rodenas, Patricia Concepción, Virginia Pérez Dieste, Alexander Missyul, Giovanni Agostini, Gonzalo Prieto   +7 more
wiley   +1 more source

A Novel High-Resolution Fully Polarization Nonparametric Spectrum Estimation Method for Forest SAR Tomography

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
The polarimetric synthetic aperture radar tomography (TomoSAR) technique has proven to be a highly promising cutting-edge microwave remote sensing technique for obtaining forest vertical structure parameters because of its ability in three-dimensional ...
Youjun Wang, Xing Peng, Qinghua Xie, Yanan Du, Bing Zhang, Xiaomin Luo, Weijun Yan, Xinwu Li   +7 more
doaj   +1 more source

Microscopic Insights into Magnetic Warping and Time‐Reversal Symmetry Breaking in Topological Surface States of Rare‐Earth‐Doped Bi2Te3

Advanced Materials, EarlyView.
Magnetic doping of the topological insulator Bi2Te3 with erbium adatoms induces out‐of‐plane magnetism and breaks time‐reversal symmetry, opening a Dirac gap and driving a Fermi surface transition from hexagonal to star‐of‐David geometry. Microscopy, spectroscopy, and magnetic dichroism reveal atomically controlled magnetic interactions that tailor the
Beatriz Muñiz Cano, Fabián Calleja, Ji Dai, Massimo Tallarida, Vera Marinova, Alessandro Barla, Marc G. Cuxart, Pierluigi Gargiani, Gonzalo N. Molina, José Angel Silva‐Guillén, Adriana I. Figueroa, Kevin García‐Díez, Sergio O. Valenzuela, Aitor Mugarza, Amadeo L. Vázquez de Parga, Rodolfo Miranda, Francisco Guinea, Manuela Garnica, Miguel A. Valbuena   +18 more
wiley   +1 more source

An Introduction to Shrinkage Estimation of the Covariance Matrix: A Pedagogic Illustration

Spreadsheets in Education, 2011
Shrinkage estimation of the covariance matrix of asset returns was introduced to the finance profession several years ago. Since then, the approach has also received considerable attention in various life science studies, as a remedial measure for ...
Clarence C. Y. Kwan
doaj  

Underdetermined Direction of Arrival Estimation of Non-Circular Signals via Matrix Completion in Nested Array

IEEE Access, 2019
Direction-of-arrival (DOA) estimation using nested linear array ignores the information from repeated sensors, thus involves the problem of losing accuracy. Moreover, non-circular feature of signals is rarely considered and it results in discontinuity of
Peng Han, Daming Wang, Weijia Cui, Jin Zhang   +3 more
doaj   +1 more source

Efficient parallel computation of the estimated covariance matrix [PDF]

2010 IEEE 26-th Convention of Electrical and Electronics Engineers in Israel, 2010
Computation of a signal's estimated covariance matrix is an important building block in signal processing, e.g., for spectral estimation. Each matrix element is a sum of products of elements in the input matrix taken over a sliding window. Any given product contributes to multiple output elements, thereby complicating parallelization.
Oded Green, Lior David, Ami Galperin, Yitzhak Birk   +3 more
openaire   +2 more sources

Large‐Scale Determination of Frontier Orbital Energies of Disordered Small‐Molecule Organic Semiconductors Using Exciplex Emission Spectra

Advanced Materials, EarlyView.
ABSTRACT Accurately knowing the frontier orbital energies of the structurally disordered small‐molecule organic semiconductors that are used in optoelectronic devices such as organic light‐emitting diodes is required to rationally improve their performance. Here, we show that these energies can be deduced with a large accuracy from the peak energies of
Christian B. McDonald, Hiroki Tomita, Giacomo Cotelli, Louka L. Brüll, Nanno G. de Rooij, Lucas R.L. Norg, Milo Clément, Reinder Coehoorn   +7 more
wiley   +1 more source

Inertia Estimation Through Covariance Matrix

IEEE Transactions on Power Systems
This work presents a technique to estimate on-line the inertia of a power system based on ambient measurements. The proposed technique utilizes the covariance matrix of these measurements and solves an optimization problem that fits such measurements to the synchronous machine classical model.
Federico Bizzarri, Davide del Giudice, Samuele Grillo, Daniele Linaro, Angelo Brambilla, Federico Milano   +5 more
openaire   +2 more sources

Electrically Coded Retinomorphic Spectrophotodetector

Advanced Materials, EarlyView.
Self‐powered retinomorphic pyro‐photodetector is demonstrated that avoids machine‐learning post‐processing and covers 365–940 nm. Electrostatic balancing of built‐in potential produces an electrical wavelength code, delivering <3 nm wavelength decoding accuracy with ∼46 µs response.
Mohit Kumar, Hyunmin Dang, Hyungtak Seo
wiley   +1 more source

Gridless DOA Estimation Method for Arbitrary Array Geometries Based on Complex-Valued Deep Neural Networks

Remote Sensing
Gridless direction of arrival (DOA) estimation methods have garnered significant attention due to their ability to avoid grid mismatch errors, which can adversely affect the performance of high-resolution DOA estimation algorithms. However, most existing
Yuan Cao, Tianjun Zhou, Qunfei Zhang
doaj   +1 more source