Three-dimensional version of the Danish Eulerian Model

1996 ◽  
pp. 151-157 ◽  
Author(s):  
I. Dimov ◽  
K. Georgiev ◽  
J. Waśniewski ◽  
Z. Zlatev
Keyword(s):  
Three Dimensional ◽  
Eulerian Model ◽  
Dimensional Version

scholarly journals Geometry of the 3D Pythagoras' Theorem

2016 ◽  
Vol 8 (6) ◽  
pp. 78 ◽  
Author(s):  
Luis Teia
Keyword(s):  
Three Dimensional ◽  
Transformation Process ◽  
Two Dimensional ◽  
Natural Evolution ◽  
Dimensional Version ◽  
Pythagoras Theorem

This paper explains step-by-step how to construct the 3D Pythagoras' theorem by geometric manipulation of the two dimensional version. In it is shown how $x+y=z$ (1D Pythagoras' theorem) transforms into $x^2+y^2=z^2$ (2D Pythagoras' theorem) via two steps: a 90-degree rotation, and a perpendicular extrusion. Similarly, the 2D Pythagoras' theorem transforms into 3D using the same steps. Octahedrons emerge naturally during this transformation process. Hence, each of the two dimensional elements has a direct three dimensional equivalent. Just like squares govern the 2D, octahedrons are the basic elements that govern the geometry of the 3D Pythagoras' theorem. As a conclusion, the geometry of the 3D Pythagoras' theorem is a natural evolution of the 1D and 2D. This interdimensional evolution begs the question -- Is there a bigger theorem at play that encompasses all three?

scholarly journals Simulation of denitrification and ozone loss for the Arctic winter 2002/2003

2005 ◽  
Vol 5 (6) ◽  
pp. 1437-1448 ◽  
Author(s):  
J.-U. Grooß ◽  
G. Günther ◽  
R. Müller ◽  
P. Konopka ◽  
S. Bausch ◽  
...  
Keyword(s):  
Inorganic Nitrogen ◽  
Potential Temperature ◽  
Three Dimensional ◽  
Lagrangian Model ◽  
The Arctic ◽  
Particle Nucleation ◽  
Ozone Loss ◽  
Dimensional Version ◽  
Total Inorganic Nitrogen ◽  
Catalytic Cycles

Abstract. We present simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) for the Arctic winter 2002/2003. We integrated a Lagrangian denitrification scheme into the three-dimensional version of CLaMS that calculates the growth and sedimentation of nitric acid trihydrate (NAT) particles along individual particle trajectories. From those, we derive the HNO3 downward flux resulting from different particle nucleation assumptions. The simulation results show a clear vertical redistribution of total inorganic nitrogen ( ), with a maximum vortex average permanent removal of over 5ppb in late December between 500 and 550K and a corresponding increase of of over 2ppb below about 450K. The simulated vertical redistribution of is compared with balloon observations by MkIV and in-situ observations from the high altitude aircraft Geophysica. Assuming a globally uniform NAT particle nucleation rate of 7.8x10-6cm-3h-1 in the model, the observed denitrification is well reproduced. In the investigated winter 2002/2003, the denitrification has only moderate impact (≤14%) on the simulated vortex average ozone loss of about 1.1ppm near the 460K level. At higher altitudes, above 600K potential temperature, the simulations show significant ozone depletion through -catalytic cycles due to the unusual early exposure of vortex air to sunlight.

scholarly journals A mass-conserving and multi-tracer efficient transport scheme in the online integrated Enviro-HIRLAM model

2013 ◽  
Vol 6 (4) ◽  
pp. 1029-1042 ◽  
Author(s):  
B. Sørensen ◽  
E. Kaas ◽  
U. S. Korsholm
Keyword(s):  
Prediction Model ◽  
Weather Prediction ◽  
Three Dimensional ◽  
Chemical Species ◽  
Numerical Weather Prediction Model ◽  
Computationally Efficient ◽  
Long Time ◽  
Dimensional Version ◽  
The Stability ◽  
Lagrangian Scheme

Abstract. In this paper a new advection scheme for the online coupled chemical–weather prediction model Enviro-HIRLAM is presented. The new scheme is based on the locally mass-conserving semi-Lagrangian method (LMCSL), where the original two-dimensional scheme has been extended to a fully three-dimensional version. This means that the three-dimensional semi-implicit semi-Lagrangian scheme which is currently used in Enviro-HIRLAM is largely unchanged. The HIRLAM model is a computationally efficient hydrostatic operational short-term numerical weather prediction model, which is used as the base for the online integrated Enviro-HIRLAM. The new scheme is shown to be efficient, mass conserving, and shape preserving, while only requiring minor alterations to the original code. It still retains the stability at long time steps, which the semi-Lagrangian schemes are known for, while handling the emissions of chemical species accurately. Several mass-conserving filters have been tested to assess the optimal balance of accuracy vs. efficiency.

Development of the Life Project Reflexivity Scale: A New Career Intervention Inventory

2018 ◽  
Vol 27 (2) ◽  
pp. 358-370 ◽  
Author(s):  
Annamaria Di Fabio ◽  
Jacobus Gideon Maree ◽  
Maureen E. Kenny
Keyword(s):  
Factor Analysis ◽  
Three Dimensional ◽  
Reliability And Validity ◽  
Well Being ◽  
Career Intervention ◽  
Life Project ◽  
Group Settings ◽  
Confirmatory Factor ◽  
Dimensional Version ◽  
Italian Context

This article describes the Life Project Reflexivity Scale ( LPRS), a questionnaire constructed for use with Italian students to assess the development of reflexivity, which is increasingly vital for personal and professional progress and well-being. The instrument was administered to 502 Italian university students. A three-dimensional version of the scale was identified through exploratory factor analysis and supported by confirmatory factor analysis. Inter-item factor and scale correlations and reliability coefficients were calculated. We concluded that evidence supports the reliability and validity of the LPRS as a useful instrument for measuring life project reflexivity (people’s reflexivity regarding their future career–life–personal projects) in the Italian context. In addition to sound psychometric properties, the LPRS takes little time to administer and can be completed in large group settings with relative ease. More research is needed to more fully assess its validity and its potential for use in other countries.

Lamb’s problem: a brief history

2019 ◽  
Vol 25 (3) ◽  
pp. 501-514
Author(s):  
Mohamad Emami ◽  
Morteza Eskandari-Ghadi
Keyword(s):  
Special Interest ◽  
Mathematical Theory ◽  
Three Dimensional ◽  
Elastic Solid ◽  
Theory Of Elasticity ◽  
Scientific Investigation ◽  
Lamb’S Problem ◽  
Solution Methods ◽  
Dimensional Version ◽  
History Of

In this review note, a historical scientific investigation is presented for Lamb’s problem in the mathematical theory of elasticity. This problem first appeared in 1904 in the pioneering paper of Professor Sir Horace Lamb (Lamb, H. On the propagation of tremors over the surface of an elastic solid. Philos Trans R Soc Lon 1904; 203: 1–42). Of special interest here are the analytical studies of the three-dimensional version of Lamb’s problem, which consists of a semi-infinite, homogeneous, isotropic elastic solid that is set in motion by the exertion of a dynamical point force applied suddenly on the surface of the domain. The objective of this paper is to offer a comprehensive introduction to Lamb’s problem for the reader, along with discussing its mathematical complexities. An account is given of the history of this ever-significant problem from its earlier stages to the more recent investigations via outlining and discussing different rigorous approaches and methods of solution that have been hitherto suggested. The limitations of different methods, if they exist, are also discussed. Eventually, various solution methods are compared considering their nature, advantages, and restrictions.

scholarly journals Using a Gyro as a Tool for Continuously Variable Lateral Stabilisation of Dynamic Bipeds

2006 ◽  
Vol 3 (3) ◽  
pp. 237-243
Author(s):  
N. M. Mayer ◽  
K. Masui ◽  
M. Browne ◽  
M. Asada ◽  
M. Ogino
Keyword(s):  
Three Dimensional ◽  
Biped Robot ◽  
Reaction Wheel ◽  
Lateral Direction ◽  
Biped Walking ◽  
Walking Machines ◽  
Different Types ◽  
Dimensional Version ◽  
World Exhibition

We present simulations of different types of biped walking machines that are stabilized in the lateral direction by adding a gyro. The simulations show that, in principle, it is indeed possible to stabilise biped walking machines. Examples presented in this work include a three-dimensional version of the simplest walking model, which is based on earlier investigations, and an actuated biped robot. Here, the gyro is used as a reaction wheel. Finally, a rotor–brake combination is outlined that was used in an artistic biped robot at the Aichi World Exhibition.

A cognitive map of indicative and subjunctive mood use in Spanish

2001 ◽  
Vol 9 (1) ◽  
pp. 99-133 ◽  
Author(s):  
Amy E. Gregory
Keyword(s):  
Three Dimensional ◽  
Cognitive Map ◽  
Information Value ◽  
General Interest ◽  
Interpersonal Dynamics ◽  
Time Line ◽  
Dimensional Version ◽  
High Level ◽  
Pragmatic Presupposition

Of general interest, this study confirms the syntactic manifestation of the interpersonal dynamics of the participants in discourse and of their high-level cognitive processes therein. More specifically, this study formalizes categories of the Spanish indicative and subjunctive in a cognitive map based on the deictic organization of the Spanish mood system. This cognitive map, based on a pragmasyntactic approach to mood use, allows us to view mood in Spanish as a mechanism that establishes metaphorical distance from the individual’s here and now. This study treats the indicative and subjunctive moods of Spanish with special attention to the so-called ‘factive’ clauses [those clauses subordinated to matrices of subjective comment such as me alegro que (I am glad that), es bueno que (It is good that), no me gusta que (I don’t like it that), etc. and mental act matrices such as darse cuenta de que (to realize that), tomar en consideración que (to take into account that), etc.]. We propose an approach to analyzing mood use that is based on the information value of an utterance in discourse. In considering information value we take into account (a) Lambrecht’s (1994) work featuring presuppositions as inherent parts of certain syntactical structures; (b) Mejías-Bikandi’s (1994) claim that the subjective comment structure in Spanish (subjective comment + que + clause marked with subjunctive) inherently contains a pragmatic presupposition; (c) Mejías-Bikandi’s reaffirmation that assertion is the role of the indicative and non-assertion is the role of the subjunctive in Spanish; (d) Lunn’s (1988, 1989a & b) suggestion that the indicative is used to assert propositions with high information value while the subjunctive’s role is to not assert propositions with low information value; and (e) Lambrecht’s (1994) ideas on what constitutes information. We assume that non-assertion, including pragmatic presupposition, and asserted propositions work together to create the relative information value of utterances. We show how the information value of utterances can be organized by means of deixis to create a cognitive map. The graphic design for the three dimensional version, which incorporates the notion of the time line with that of metaphorical distance from any individual’s deictic center, was inspired by Langacker’s (1991) Cognitive Gram- mar.

A Numerical Study of Droplet Impingement for In-Flight Ice Accretion Prediction

2016 ◽  
Author(s):  
Hao Zhang ◽  
Chihyung Wen ◽  
Junwei Su
Keyword(s):  
Collection Efficiency ◽  
Numerical Study ◽  
Three Dimensional ◽  
Ice Accretion ◽  
Eulerian Model ◽  
Droplet Impingement ◽  
Basic Module ◽  
Wide Range ◽  
Subsonic Regime ◽  
Finite Volume Approach

Droplet impingement is the basic module in both ice accretion and anti-icing numerical calculation. A three dimensional finite volume approach with the capacity of modeling the in-flight droplet impingement on a wide range of subsonic regime is therefore established in this research, using OpenFOAM®. The Eulerian model is applied to estimate the droplet flow field with the same computational grid sets as those of the air flow calculation. The roughness effect caused by ice accretion is considered in the wall function modeling. Thus, the collection efficiency could be investigated for further icing numerical simulations. This approach is validated on both cylinder and sphere benchmark cases. The results are compared with the corresponding experimental and LEWICE (LEWis ICE accretion program) simulation data.

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