Extension of an orographic-drag parametrization scheme to incorporate orographic anisotropy and flow blocking

2005 ◽  
Vol 131 (609) ◽  
pp. 1893-1921 ◽  
Author(s):  
Young-Joon Kim ◽  
James D. Doyle
Keyword(s):  
Parametrization Scheme ◽  
Orographic Drag

scholarly journals An Orographic‐Drag Parametrization Scheme Including Orographic Anisotropy for All Flow Directions

2020 ◽  
Vol 12 (3) ◽  
Author(s):  
Jinbo Xie ◽  
Minghua Zhang ◽  
Zhenghui Xie ◽  
Hailong Liu ◽  
Zhaoyang Chai ◽  
...  
Keyword(s):  
Parametrization Scheme ◽  
Flow Directions ◽  
Orographic Drag

A Parametrization Scheme for the Burmester Curves

1998 ◽  
Author(s):  
Siddhartha Niyogi ◽  
Gary L. Kinzel
Keyword(s):  
Complex Number ◽  
Graphical Method ◽  
Parametric Representation ◽  
Basic Theory ◽  
Systematic Search ◽  
Alternative Scheme ◽  
Cartesian Coordinates ◽  
Parametrization Scheme ◽  
Automatic Search

Abstract The cubic representation of the Burmester curve in Cartesian coordinates has certain disadvantages when automated searches are carried out. A parametric representation of the curve would be ideal. A systematic search could then be carried out by tracking points in a continuous fashion along the curve. In addition, solution rectification methods could be applied to determine the feasible segments, and the search could be limited to those portions only. This paper presents an alternative scheme for parametrizing the Burmester curves, as opposed to the complex number approach used by Chase et al. It uses the graphical method as its basis. The final scheme is not single valued, as it involves a parameter value as well a sign variable, but otherwise fulfils the requirements for an automatic search. It is an improvement on the cubic representation as it is double valued, rather than triple valued. The basic theory associated with the parametrization and the issues arising out of it are developed.

Evaluation of WRF Simulations With Different Selections of Subgrid Orographic Drag Over the Tibetan Plateau

2017 ◽  
Vol 122 (18) ◽  
pp. 9759-9772 ◽  
Author(s):  
X. Zhou ◽  
A. Beljaars ◽  
Y. Wang ◽  
B. Huang ◽  
C. Lin ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
The Tibetan Plateau ◽  
Orographic Drag

A Mathematical Model of Parathyroid Hormone Response to Acute Changes in Plasma Ionized Calcium Concentration in Humans

2008 ◽  
Author(s):  
Rajiv P. Shrestha ◽  
Yossi Chait ◽  
Christopher V. Hollot ◽  
Stuart Chipkin ◽  
Claus P. Schmitt
Keyword(s):  
Calcium Concentration ◽  
Linear Time ◽  
Ionized Calcium ◽  
Time Varying ◽  
Qualitative Model ◽  
Hormone Response ◽  
Clinical Tests ◽  
Parametrization Scheme ◽  
Normal Humans ◽  
Acute Changes

A complex bio-mechanism, referred to as calcium homeostasis, regulates plasma ionized calcium (Ca++) concentration in the human body to within a narrow physiologic range which is crucial for maintaining normal physiology and metabolism. In this paper we present a qualitative model of the calcium homeostatic system and then focus on a particular sub-system, termed Ca-PTH axis. We consider the dynamics of the axis involving the response of the parathyroid glands to acute changes in plasma Ca++ concentration. We use a two-pool, linear time-varying model to describe the Ca-PTH axis. We show that this model, parameterized using a guided iterative parametrization scheme and induced hypocalcemic clamp test data, successfully predicts dynamics observed in clinical tests of induced hypercalcemia in normal humans.

Extended parametrization scheme of f-spectra

2007 ◽  
Vol 127 (2) ◽  
pp. 552-560 ◽  
Author(s):  
A. Ke¸dziorski ◽  
Lidia Smentek
Keyword(s):  
Parametrization Scheme

A Microstructure-Level Material Model for Simulating the Machining of Carbon Nanotube Reinforced Polymer Composites

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
Ashutosh Dikshit ◽  
Johnson Samuel ◽  
Richard E. DeVor ◽  
Shiv G. Kapoor
Keyword(s):  
Carbon Nanotube ◽  
Weight Fraction ◽  
Material Model ◽  
Material Behavior ◽  
Compression Tests ◽  
Linear Elastic ◽  
Rate Dependent ◽  
Wide Range ◽  
Parametrization Scheme ◽  
Fraction Length

A continuum-based microstructure-level material model for simulation of polycarbonate carbon nanotube (CNT) composite machining has been developed wherein polycarbonate and CNT phases are modeled separately. A parametrization scheme is developed to characterize the microstructure of composites having different loadings of carbon nanotubes. The Mulliken and Boyce constitutive model [2006, “Mechanics of the Rate Dependent Elastic Plastic Deformation of Glassy Polymers from Low to High Strair Rates,” Int. J. Solids Struct., 43(5), pp. 1331–1356] for polycarbonate has been modified and implemented to capture thermal effects. The CNT phase is modeled as a linear elastic material. Dynamic mechanical analyzer tests are conducted on the polycarbonate phase to capture the changes in material behavior with temperature and strain rate. Compression tests are performed over a wide range of strain rates for model validation. The model predictions for yield stress are seen to be within 10% of the experimental results for all the materials tested. The model is used to study the effect of weight fraction, length, and orientation of CNTs on the mechanical behavior of the composites.

A PARAMETRIZED VARIABLE DARK ENERGY MODEL: STRUCTURE FORMATION AND OBSERVATIONAL CONSTRAINTS

2006 ◽  
Vol 15 (09) ◽  
pp. 1455-1472 ◽  
Author(s):  
S. ARBABI BIDGOLI ◽  
M. SADEGH MOVAHED ◽  
S. RAHVAR
Keyword(s):  
Dark Energy ◽  
Dark Energy Model ◽  
Large Scale ◽  
High Redshift ◽  
Growth Index ◽  
Energy Model ◽  
Linear Perturbation ◽  
Model Parameters ◽  
Type Ia ◽  
Parametrization Scheme

In this paper we investigate a simple parametrization scheme of the quintessence model given by Wetterich [Phys. Lett. B594, 17 (2004)]. The crucial parameter of this model is the bending parameter b, which is related to the amount of dark energy in the early universe. Using the linear perturbation and the spherical infall approximations, we investigate the evolution of matter density perturbations in the variable dark energy model, and obtain an analytical expression for the growth index f. We show that increasing b leads to less growth of the density contrast δ, and also decreases the growth index. Giving a fitting formula for the growth index at the present time, we verify that the approximation relation [Formula: see text] also holds in this model. To compare predictions of the model with observations, we use the Supernovae type Ia (SNIa) Gold Sample and the parameters of the large scale structure determined by the 2-degree Field Galaxy Redshift Survey (2dFGRS). The best fit values for the model parameters by marginalizing on the remained ones, are [Formula: see text], [Formula: see text] and [Formula: see text] at 1σ confidence level. As a final test we calculate the age of universe for different choices of the free parameters in this model and compare it with the age of old stars and some high redshift objects. Then we show that the predictions of this variable dark energy model are consistent with the age observation of old star and can solve the "age crisis" problem.

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