Results 71 to 80 of about 613,393 (297)

Covariance estimation via Fourier method in the presence of asynchronous trading and microstructure noise [PDF]

We analyze the effects of market microstructure noise on the Fourier estimator of multivariate volatilities. We prove that the estimator is consistent in the case of asynchronous data and robust in the presence of microstructure noise.
S. Sanfelici, M. E. Mancino
core  

The Influence of Wheel/Rail Contact Conditions on the Microstructure and Hardness of Railway Wheels [PDF]

, 2014
The susceptibility of railway wheels to wear and rolling contact fatigue damage is influenced by the properties of the wheel material (microstructure and hardness).
Bevan, Adam, Claire Davis, Paul Molyneux-Berry, Adam Bevan, Molyneux-Berry, Paul, Davis, Claire, Molyneux-Berry, Paul; id_orcid, Bevan, Adam; id_orcid   +7 more
core   +1 more source

High‐Temperature Phase Transformation in a V‐9Si‐6.5B Alloy: The Kinetic and Crystallographic Pathway From V5SiB2 to V8SiB4

Advanced Engineering Materials, EarlyView.
In situ synchrotron high‐energy X‐ray diffraction reveals the real‐time high‐temperature phase evolution of a ternary V‐9Si‐6.5B alloy. The study uncovers a kinetically delayed V5SiB2 → V8SiB4 transformation governed by massive structural and chemical barriers.
Zahra Sabeti, Andreas Stark, Roja Rani Korrayi, Florian Pyczak, Georg Hasemann   +4 more
wiley   +1 more source

Dominant Influence of Interface Roughness Scattering on the Performance of GaN Terahertz Quantum Cascade Lasers

Nanoscale Research Letters, 2019
Effect of interface roughness of quantum wells, non-intentional doping, and alloy disorder on performance of GaN-based terahertz quantum cascade lasers (QCL) has been investigated by the formalism of nonequilibrium Green’s functions.
Junyan Cheng, Patrick Quach, Ding Wang, Fang Liu, Shangfeng Liu, Liuyun Yang, Huapeng Liu, Bo Shen, Yuzhen Tong, Xinqiang Wang   +9 more
doaj   +1 more source

Bayesian Analysis of Structural Credit Risk Models with Microstructure Noises [PDF]

In this paper a Markov chain Monte Carlo (MCMC) technique is developed for the Bayesian analysis of structural credit risk models with microstructure noises. The technique is based on the general Bayesian approach with posterior computations performed by
Jun Yu, Shirley J. Huang
core  

Impact of MgO Additions on the Oxidation Resistance and Compression Behavior of Vanadium Alloys

Advanced Engineering Materials, EarlyView.
An increase in oxidation resistance at 600 °C is achieved for alloys containing more than 2.5 wt.% MgO. It has been established that, along with V2O5, MgO6V2, and Mg2O7V2 are formed, which are presumed to enhance oxidative stability. Furthermore, the possible transformation of Mg‐vanadates through reaction with CO2, which presumably occurs in this ...
Ievgen Solodkyi, Mathias Galetz, Georg Hasemann, Fabian Lanoy, Emma White, Manja Krüger   +5 more
wiley   +1 more source

Long-range phase coherence and tunable second order φ 0-Josephson effect in a Dirac semimetal 1T-PtTe2

Communications Physics
Superconducting diode effects have recently attracted much attention for their potential applications in superconducting logic circuits. Several pathways have been proposed to give rise to non-reciprocal critical currents in various superconductors and ...
Pranava K. Sivakumar, Mostafa T. Ahari, Jae-Keun Kim, Yufeng Wu, Anvesh Dixit, George J. de Coster, Avanindra K. Pandeya, Matthew J. Gilbert, Stuart S. P. Parkin   +8 more
doaj   +1 more source

Additive manufacturing of magnesium and its alloys: process-formability-microstructure-performance relationship and underlying mechanism

, 2023
Highlights The process-formability-microstructure-performance relationship in additively manufactured Mg and its alloys was reviewed.
X Wu (660808), D Ma (10645809), S Sui (13297140), D Shechtman (13641046), Rimma Lapovok (13091118), C Guo (7947251), S Remennik (18512901), D Safranchik (18512904), S Guo (6097922), Z Zhang (7695560), C Xu (7775762)   +10 more
core  

Distinct Microstructural Characteristic Lengths Defining Notch Fatigue Crack Initiation and Propagation, and Defect Tolerance in Advanced Steels

Advanced Engineering Materials, EarlyView.
Schematic representation of modes of microcrack nucleation, growth and temporary arrestment at different boundaries, with the criteria for crack propagation in three scenarios: (1) large notch, (2) defect/small sharp notch, and (3) long crack. This work revisits and integrates results on the fatigue behavior of advanced bainitic steels (in particular ...
Lucia Morales‐Rivas
wiley   +1 more source

Local surface plasmon enhanced polarization and internal quantum efficiency of deep ultraviolet emissions from AlGaN-based quantum wells

Scientific Reports, 2017
We report the enhancement of the polarization and internal quantum efficiency (IQE) of deep-UV LEDs by evaporating Al nanoparticles on the device surface to induce localized surface plasmons (LSPs).
Cai Zhang, Ning Tang, Liangliang Shang, Lei Fu, Weiying Wang, Fujun Xu, Xinqiang Wang, Weikun Ge, Bo Shen   +8 more
doaj   +1 more source