Results 91 to 100 of about 309,815 (270)
Optimal model‐based design of experiments for parameter precision: Supercritical extraction case
Abstract This study investigates the process of chamomile oil extraction from flowers. A parameter‐distributed model consisting of a set of partial differential equations is used to describe the governing mass transfer phenomena in a cylindrical packed bed with solid chamomile particles under supercritical conditions using carbon dioxide as a solvent ...
Oliwer Sliczniuk, Pekka Oinas
wiley +1 more source
Algebraic geometry of crossed products
For projective variety X we introduce a C*-algebra A_X defined as the norm-closure of representation of the twisted homogeneous coordinate ring of X by the linear operators on a Hilbert space H.
Nikolaev, Igor
core
Subuniformity of harmonic mean p$$ p $$‐values
Abstract We obtain several inequalities on the generalized means of dependent p$$ p $$‐values. In particular, the weighted harmonic mean of p$$ p $$‐values is strictly subuniform under several dependence assumptions of p$$ p $$‐values, including independence, negative upper orthant dependence, the class of extremal mixture copulas, and some Clayton ...
Yuyu Chen +3 more
wiley +1 more source
A Markov approach to credit rating migration conditional on economic states
Abstract We develop a model for credit rating migration that accounts for the impact of economic state fluctuations on default probabilities. The joint process for the economic state and the rating is modelled as a time‐homogeneous Markov chain. While the rating process itself possesses the Markov property only under restrictive conditions, methods ...
Michael Kalkbrener, Natalie Packham
wiley +1 more source
Bayesian inverse ensemble forecasting for COVID‐19
Abstract Variations in strains of COVID‐19 have a significant impact on the rate of surges and on the accuracy of forecasts of the epidemic dynamics. The primary goal for this article is to quantify the effects of varying strains of COVID‐19 on ensemble forecasts of individual “surges.” By modelling the disease dynamics with an SIR model, we solve the ...
Kimberly Kroetch, Don Estep
wiley +1 more source
Self‐Similar Blowup for the Cubic Schrödinger Equation
ABSTRACT We give a rigorous proof for the existence of a finite‐energy, self‐similar solution to the focusing cubic Schrödinger equation in three spatial dimensions. The proof is computer‐assisted and relies on a fixed point argument that shows the existence of a solution in the vicinity of a numerically constructed approximation.
Roland Donninger, Birgit Schörkhuber
wiley +1 more source
ABSTRACT A methodological study is presented on a noninvasive photometric diagnostic for determining trends in electron density and sheath dynamics in single (1f) and a dual (2f) radio frequency capacitively coupled (CCRF) argon plasmas. The 1f discharges are operated at 13.56 and 27.12 MHz, respectively, while the 2f discharge is driven by both ...
Daniel Zuhayra +3 more
wiley +1 more source
Dynamic geometry: An agent for the reunification of algebra and geometry
This paper investigates the degree of separation or unity between the algebraic and geometric modes of thought of students in tertiary education. Case studies indicate that as a student is inducted into the use of algebra the insightful and visual ...
Meira Hockman
doaj +1 more source
Study on fracture parameter calibration and failure characteristics of rock with hole and crack
The SIF and plastic zone equations for a single hole and crack have been derived. The model's failure state leads to the identification of four types of cracks. The plastic zone increases with increased brittleness and decreased crack length. Abstract Cracks within the surrounding rock of roadways significantly affect their stability and failure ...
Shaochi Peng, Wensong Wang
wiley +1 more source
Review and prospects of shear test of bolted rock joints
The laboratory shear test equipment, test method, and numerical simulation of bolted rock joints were summarized. The shortcomings and limitations of the current research were analyzed, and the research prospects were proposed. Abstract Rock bolting is a critical approach in geotechnical engineering for supporting weak rocks.
Shulin Ren +4 more
wiley +1 more source

