Estimation of Variable Fluids Mixture Density With 4D NMR Logging

2007 ◽  
Author(s):  
Chanh Cao Minh ◽  
Emmanuel Caroli ◽  
Padmanabhan Sundararaman
Keyword(s):  
Nmr Logging ◽  
Mixture Density ◽  
4D Nmr

ARTIFICIAL INTELLIGENCE APPLIED TO NMR LOGGING FOR ROCK AND FLUID TYPING IN HEAVY OILS

2019 ◽  
Author(s):  
Pedro Romero Rojas ◽  
◽  
Alexandrina Cristea ◽  
Paul Pavlakos ◽  
Okan Ergündüz ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Heavy Oils ◽  
Nmr Logging

Free Level Effect on the Impeller Power Input in Baffled Tanks

1995 ◽  
Vol 60 (8) ◽  
pp. 1274-1280 ◽  
Author(s):  
Kamil Wichterle
Keyword(s):  
Reynolds Number ◽  
Power Input ◽  
Dimensionless Number ◽  
Simple Correlation ◽  
Mixture Density ◽  
Surface Aeration ◽  
Free Level ◽  
High Reynolds ◽  
Level Effect ◽  
Turbine Impeller

Analysis of extended data on turbine impeller power input in geometrically similar agitated baffled tanks shows that the power number Po is a function of Reynolds number Po = Po*(Re) until the emergence of surface aeration. Though it is usually anticipated that Po* = const in high Reynolds number region, some, whatever weak, function should be taken into consideration in more detailed analysis of the power data even here. In practice, disturbances of level and gas captured in the impeller region play also a significant role, namely in smaller tanks at higher impeller speeds. Decrease of power input can be explained by decrease of gas-liquid mixture density, or in other words by increase of efficient gas holdup eE just in the impeller region. The value eE defined by the relation Po = Po*(Re)/(1 + eE) was determined from the available data. Like other effects of the surface aeration it depends mainly on the dimensionless number Nc = (We Fr)1/4. A simple correlation eE (Nc) is suggested as a correction factor for prediction of impeller power in presence of gas capture.

scholarly journals Probabilistic Flight Delay Predictions Using Machine Learning and Applications to the Flight-to-Gate Assignment Problem

Aerospace ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 152
Author(s):  
Micha Zoutendijk ◽  
Mihaela Mitici
Keyword(s):  
Assignment Problem ◽  
Absolute Error ◽  
Aviation Industry ◽  
Probabilistic Forecasting ◽  
Flight Delays ◽  
Mixture Density ◽  
Assignment Model ◽  
Gate Assignment ◽  
Flight Delay ◽  
Delay Prediction

The problem of flight delay prediction is approached most often by predicting a delay class or value. However, the aviation industry can benefit greatly from probabilistic delay predictions on an individual flight basis, as these give insight into the uncertainty of the delay predictions. Therefore, in this study, two probabilistic forecasting algorithms, Mixture Density Networks and Random Forest regression, are applied to predict flight delays at a European airport. The algorithms estimate well the distribution of arrival and departure flight delays with a Mean Absolute Error of less than 15 min. To illustrate the utility of the estimated delay distributions, we integrate these probabilistic predictions into a probabilistic flight-to-gate assignment problem. The objective of this problem is to increase the robustness of flight-to-gate assignments. Considering probabilistic delay predictions, our proposed flight-to-gate assignment model reduces the number of conflicted aircraft by up to 74% when compared to a deterministic flight-to-gate assignment model. In general, the results illustrate the utility of considering probabilistic forecasting for robust airport operations’ optimization.

Pattern and mechanism of airway response to hypocapnia in normal subjects

1979 ◽  
Vol 47 (1) ◽  
pp. 8-12 ◽  
Author(s):  
C. F. O'Cain ◽  
M. J. Hensley ◽  
E. R. McFadden ◽  
R. H. Ingram
Keyword(s):  
Vital Capacity ◽  
Normal Subjects ◽  
Oxygen Mixture ◽  
Flow Volume ◽  
Mixture Density ◽  
Lung Capacity ◽  
Airway Constriction ◽  
Maximal Expiratory Flow ◽  
Airway Response ◽  
Expiratory Flow

We examined the bronchoconstriction produced by airway hypocapnia in normal subjects. Maximal expiratory flow at 25% vital capacity on partial expiratory flow-volume (PEFV) curves fell during hypocapnia both on air and on an 80% helium- 20% oxygen mixture. Density dependence also fell, suggesting predominantly small airway constriction. The changes seen on PEFV curves were not found on maximal expiratory flow-volume curves, indicating the inhalation to total lung capacity substantially reversed the constriction. Pretreatment with a beta-sympathomimetic agent blocked the response, whereas atropine pretreatment did not, suggesting that hypocapnia affects airway smooth muscle directly, not via cholinergic efferents.

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