Modelling of Isolated Systems

2018 ◽  
pp. 33-67
Author(s):  
Anindita Roy ◽  
Santanu Bandyopadhyay
Keyword(s):  
Isolated Systems

COVARIANT CONFORMAL DECOMPOSITION OF EINSTEIN EQUATIONS

2002 ◽  
Vol 17 (20) ◽  
pp. 2762-2762
Author(s):  
E. GOURGOULHON ◽  
J. NOVAK
Keyword(s):  
Numerical Simulations ◽  
Extrinsic Curvature ◽  
Einstein Equations ◽  
Numerical Implementation ◽  
Einstein’S Equations ◽  
Einstein's Equations ◽  
Tensor Density ◽  
Dirac Gauge ◽  
Ill Posed ◽  
Isolated Systems

It has been shown1,2 that the usual 3+1 form of Einstein's equations may be ill-posed. This result has been previously observed in numerical simulations3,4. We present a 3+1 type formalism inspired by these works to decompose Einstein's equations. This decomposition is motivated by the aim of stable numerical implementation and resolution of the equations. We introduce the conformal 3-"metric" (scaled by the determinant of the usual 3-metric) which is a tensor density of weight -2/3. The Einstein equations are then derived in terms of this "metric", of the conformal extrinsic curvature and in terms of the associated derivative. We also introduce a flat 3-metric (the asymptotic metric for isolated systems) and the associated derivative. Finally, the generalized Dirac gauge (introduced by Smarr and York5) is used in this formalism and some examples of formulation of Einstein's equations are shown.

Energy genaration from natural gas in brazilian isolated systems: challenges and opportunities

2020 ◽  
Vol 20 (2020) ◽  
pp. 312-313
Author(s):  
Thiago Ivanoski ◽  
Gustavo Pires Da Ponte ◽  
Jorge Gonçalves Bezerra Júnior ◽  
Michele Souza ◽  
Aline Couto De Amorim ◽  
...  
Keyword(s):  
Natural Gas ◽  
Challenges And Opportunities ◽  
Isolated Systems

scholarly journals Random k-Body Ensembles for Chaos and Thermalization in Isolated Systems

Entropy ◽  
2018 ◽  
Vol 20 (7) ◽  
pp. 541 ◽  
Author(s):  
Venkata Kota ◽  
Narendra Chavda
Keyword(s):  
Hermite Polynomials ◽  
Point Group ◽  
Majorana Fermions ◽  
Many Body ◽  
Boson Systems ◽  
Random Matrix Ensembles ◽  
Isolated Systems ◽  
Group Symmetries ◽  
Statistical Relaxation

Embedded ensembles or random matrix ensembles generated by k-body interactions acting in many-particle spaces are now well established to be paradigmatic models for many-body chaos and thermalization in isolated finite quantum (fermion or boson) systems. In this article, briefly discussed are (i) various embedded ensembles with Lie algebraic symmetries for fermion and boson systems and their extensions (for Majorana fermions, with point group symmetries etc.); (ii) results generated by these ensembles for various aspects of chaos, thermalization and statistical relaxation, including the role of q-hermite polynomials in k-body ensembles; and (iii) analyses of numerical and experimental data for level fluctuations for trapped boson systems and results for statistical relaxation and decoherence in these systems with close relations to results from embedded ensembles.

Path-dependent phase shifts in isolated systems

1996 ◽  
Vol 35 (2) ◽  
pp. 333-340 ◽  
Author(s):  
Xiaoyan Yu ◽  
Walter C. Henneberger
Keyword(s):  
Phase Shifts ◽  
Path Dependent ◽  
Isolated Systems

scholarly journals Irreversibility of time for quasi-isolated systems

2003 ◽  
Vol 308 (5-6) ◽  
pp. 313-318 ◽  
Author(s):  
V.I. Yukalov
Keyword(s):  
Isolated Systems

Temperature concepts for small, isolated systems; 1/t decay and radiative cooling

2003 ◽  
Vol 24 (1-3) ◽  
pp. 191-196 ◽  
Author(s):  
J. U. Andersen ◽  
E. Bonderup ◽  
K. Hansen ◽  
P. Hvelplund ◽  
B. Liu ◽  
...  
Keyword(s):  
Radiative Cooling ◽  
Isolated Systems

Step-based evolution support among networked production automation systems

2018 ◽  
Vol 66 (10) ◽  
pp. 849-858
Author(s):  
Christopher Haubeck ◽  
Heiko Bornholdt ◽  
Winfried Lamersdorf ◽  
Abhishek Chakraborty ◽  
Alexander Fay
Keyword(s):  
Production Systems ◽  
Cyber Physical Systems ◽  
Peer To Peer ◽  
Evolution Process ◽  
Physical Systems ◽  
Model Based ◽  
Automation Systems ◽  
Production Automation ◽  
Isolated Systems

Abstract Production systems are no longer rigid, unyielding, and isolated systems anymore. They are rather interconnected cyber-physical systems with an evolution process that needs to be supported. To enable reusability in evolution, a change-first cooperative support is proposed that relies on model-based evolution steps. The approach establishes a network-wide evolution process in a peer-to-peer networked community. Thus, moving towards decentralised marketplaces for evolution steps.

scholarly journals FOTODIM—Software for Sizing of Photovoltaic Systems

2019 ◽  
Vol 11 (3) ◽  
pp. 137
Author(s):  
Daisy Regina dos Santos ◽  
Carlos Eduardo Camargo Nogueira ◽  
Felix Augusto Pazuch ◽  
Francielle Pareja Schneider ◽  
Jair Antonio Cruz Siqueira ◽  
...  
Keyword(s):  
Theoretical Basis ◽  
Net Present Value ◽  
Photovoltaic System ◽  
Photovoltaic Systems ◽  
Internal Rate Of Return ◽  
Computational Tool ◽  
Present Value ◽  
Grid Systems ◽  
Digital Book ◽  
Isolated Systems

This study addresses the development of a computational tool for the sizing of photovoltaic systems interconnected to the grid (grid-tied) and isolated (off-grid) systems. The calculations for the sizing were obtained from the CRESESB Engineering Manual for Photovoltaic Systems, the GREENPO Photovoltaic Systems Technology, Design and Installation Manual, and the BLUESOL Solar System Introduction Digital Book. With knowledge of the latitude, longitude and altitude data of the site, the tool calculates the angle of the modules for better absorption of the photovoltaic radiation. For systems connected to the grid, it is also necessary to provide information on the consumption of the building to be serviced by the photovoltaic system. For isolated systems, in addition to information on the site, it is necessary to know the demand and consumption of the building. Decision-making criteria are based on economic analysis, according to indexes such as Net Present Value (NPV), Internal Rate of Return (IRR), and Discounted Payback. The screens developed for the sizing tool and examples of sizing of both photovoltaic systems are presented as results, through tables and graphs. The developed software is reliable, and all calculations have theoretical basis.

scholarly journals Why Experimentum Crucis is Possible in Psychology of Perception

2018 ◽  
Vol 40 (1) ◽  
pp. 45-57 ◽  
Author(s):  
Michele Sinico
Keyword(s):  
Psychological Research ◽  
Perceptual Knowledge ◽  
Experimental Phenomenology ◽  
Phenomenology Of Perception ◽  
Scientific Disciplines ◽  
Isolated Systems ◽  
High Degree ◽  
Essential Assumption

Summary This paper examines the experimentum crucis under the light of the Duhem’s holistic thesis. This methodological instrument is not usable in physics, because physical theories are always logically connected to many assumptions. On the contrary, it is usable in psychological research oriented to perceptual laws, when these laws are, without any hypothetical term, isolated systems. An application of experimentum crucis in Experimental Phenomenology of perception is presented. In conclusion, the role of perceptual knowledge as an essential assumption in other scientific disciplines that have a high degree of theoricity is also underlined.

Sign in / Sign up

Export Citation Format

Share Document