scholarly journals Aspects of the polynomial affine model of gravity in three dimensions

2022 ◽  
Vol 82 (1) ◽  
Author(s):  
Oscar Castillo-Felisola ◽  
Oscar Orellana ◽  
José Perdiguero ◽  
Francisca Ramírez ◽  
Aureliano Skirzewski ◽  
...  

AbstractThe polynomial affine gravity is a model that is built up without the explicit use of a metric tensor field. In this article we reformulate the three-dimensional model and, given the decomposition of the affine connection, we analyse the consistently truncated sectors. Using the cosmological ansatz for the connection, we scan the cosmological solutions on the truncated sectors. We discuss the emergence of different kinds of metrics.

1977 ◽  
Vol 18 (80) ◽  
pp. 373-389 ◽  
Author(s):  
D. Jenssen

AbstractA three-dimensional model of the temperature and velocity distribution within any arbitrary-shaped ice mass is described. There is a mutual interaction in the model between the flow of the ice and its thermodynamics, since the flow law used in the model is temperature-dependent.Ice growth in three dimensions is governed by mass accumulation through precipitation, by mass depletion through loss of ice over the ocean, and by continuity requirements. Phase changes at the base of the ice are accounted for. The model has been applied in art exploratory manner to the Greenland ice sheet. Changes in the ice shape and temperature are presented and discussed. The basic shortcoming of the model as here presented appears primarily due to the coarse finite-difference mesh used, and to an unsophisticated approach to modelling the boundary ice.


Mathematics ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 553 ◽  
Author(s):  
Essam R. El-Zahar ◽  
Abdelhalim Ebaid ◽  
Abdulrahman F. Aljohani ◽  
José Tenreiro Machado ◽  
Dumitru Baleanu

This paper re-analyzes the falling body problem in three dimensions, taking into account the effect of the Earth’s rotation (ER). Accordingly, the analytic solution of the three-dimensional model is obtained. Since the ER is quite slow, the three coupled differential equations of motion are usually approximated by neglecting all high order terms. Furthermore, the theoretical aspects describing the nature of the falling point in the rotating frame and the original inertial frame are proved. The theoretical and numerical results are illustrated and discussed.


Author(s):  
A. B. Lachikhina ◽  
K. N. Soldatov

Visualization of analyzing multidimensional data is often required in order to improve perception and visibility. The purpose of this research is a multidimensional array of data representation. It is proposed to use a three-dimensional model as a tool. The methods used to represent an array of data with more than three dimensions are presented. The principle of constructing a multidimensional array cell is considered. An example of the constructed hypercube cell is given. The formulas for calculating the number of faces of the figure, the number of triangles that can be built through points, the number of internal triangles are obtained. The approach of visualization of aggregates is described. The use of color gradation to improve the convenience of perception of the cell in the analysis of the cube cells. It is concluded that the proposed model allows us to perceive each cell as an independent data element in the construction of charts for the analyzed indicators.


1971 ◽  
Vol 3 (3) ◽  
pp. 253-266 ◽  
Author(s):  
A Faludi

This paper develops conceptual tools for the analysis of planning behaviour. These are, firstly, a model of planning systems as learning systems, and then three dimensions of planning behaviour, each described by defining a pair of dichotomous concepts at their far ends: ‘blueprint’ versus ‘process’ modes of planning; ‘rational-deductive’ decision-making versus ‘disjointed incrementalism’; ‘normative’ versus ‘functional’ planning. Each of these concepts is discussed in detail, and some indicators for the analysis of planning behaviour are suggested. Finally, a more complex model is constructed which combines the three dimensions. Elements of this model are firstly the level at which planning is conducted within a hierarchy of planning systems, and secondly, the ‘planning sub-structurel, that is the technology-image reflecting the nature of planning problems and available planning technologies. From this model one can derive a number of researchable hypotheses about planning behaviour.


1977 ◽  
Vol 18 (80) ◽  
pp. 373-389 ◽  
Author(s):  
D. Jenssen

Abstract A three-dimensional model of the temperature and velocity distribution within any arbitrary-shaped ice mass is described. There is a mutual interaction in the model between the flow of the ice and its thermodynamics, since the flow law used in the model is temperature-dependent. Ice growth in three dimensions is governed by mass accumulation through precipitation, by mass depletion through loss of ice over the ocean, and by continuity requirements. Phase changes at the base of the ice are accounted for. The model has been applied in art exploratory manner to the Greenland ice sheet. Changes in the ice shape and temperature are presented and discussed. The basic shortcoming of the model as here presented appears primarily due to the coarse finite-difference mesh used, and to an unsophisticated approach to modelling the boundary ice.


Plant Disease ◽  
2020 ◽  
Author(s):  
Wanli Cheng ◽  
Zhen Chen ◽  
Li Zeng ◽  
Xue Yang ◽  
Dian Huang ◽  
...  

Meloidogyne incognita causes large-scale losses of agricultural crops worldwide. The natural metabolite furfural acetone has been reported to attract and kill M. incognita, but whether the attractant and nematicidal activities of furfural acetone on M. incognita function simultaneously in the same system, especially in three dimensions or in soil, is still unknown. Here, we used 23% pluronic F-127 gel and a soil simulation device to demonstrate that furfural acetone has a significant attract-and-kill effect on M. incognita in both three-dimensional model systems. At 24 h, the chemotaxis index and corrected mortality of nematodes exposed to 60 mg/mL furfural acetone in 23% pluronic F-127 gel were as high as 0.82 and 74.44%, respectively. Soil simulation experiments in moist sand showed that at 48 h, the chemotaxis index and corrected mortality of the nematode towards furfural acetone reached 0.63 and 82.12%, respectively, and the effect persisted in the presence of tomato plants. In choice experiments, nematodes selected furfural acetone over plant roots and were killed subsequently. In pot studies, furfural acetone had a control rate of 82.80% against M. incognita. Collectively, these results provide compelling evidence for further investigation of furfural acetone as a novel nematode control agent.


Author(s):  
Michał Sękowski ◽  
Łukasz Subramanian ◽  
Magdalena Żemojtel-Piotrowska

AbstractIn this paper, we focused on the poorly understood and rarely researched relationship between resilience and narcissism, adopting the adjective-based measures of narcissism. We examine how levels of resilience are related to grandiose and vulnerable narcissism, based on a three-dimensional model of resilience (i.e., ecological resilience, engineering resilience, and adaptive capacity). Using self-report, cross-sectional data from a general Polish sample (N = 657), we found that grandiose narcissism was positively related to all three dimensions of resilience, while vulnerable narcissism was negatively related to them. Grandiose narcissism was most strongly associated with adaptive capacity where vulnerable narcissism was mostly strongly associated with engineering resilience. We discuss our findings in relation to the function of two forms of narcissism may yield different capacities for stress management and recovery after experiencing stressful events. Therefore, this research is focused on self-report and we look forward to expand our research by behavioral indices in the future.


2020 ◽  
Vol 13 (1) ◽  
pp. 37-55
Author(s):  
Hakan Ünal ◽  
Csilla Obádovics ◽  
Emese Bruder

This study introduces a method for measuring standard of living, based on a three-dimensional model. The authors argue that their proposed indicators (and items) can more realistically capture people’s inability to afford an adequate way of living than the ones Eurostat uses and recommends. The commonly used deprivation measuring method has a unidimensional perspective and provides only a general overview of those living in deprivation. The authors’ multidimensional approach, however, considers not only the well-known aspects of human life but also others, giving a more extensive view of individuals’ needs. The calculations are based on the European Union Statistics on Income and Living Conditions database provided by Eurostat and the relevant Turkish data¬base from the Turkish Statistical Office. The decomposite method introduced in the study measures standard of living using three dimensions, economic strain, living conditions, and housing and environmental conditions.


The first part of this work described the analysis of the structure by trial and gave some account of the experimental measurements. It was shown that in contrast with planar aromatic structures like naphthalene and diphenyl, the dibenzyl molecule in the crystal extends in three dimensions. In the molecular model which gave the best explanation of the results the planes of the benzene rings were at right angles to the plane containing the zig-zag of the connecting CH 2 groups. On the basis of this approximation the experimentally determined structure factors for three zones of reflections have now been subjected to a double Fourier analysis, and the results, given below, lead to a more precise definition of the orientation and give a more direct approach to the details of the molecular structure and dimensions. In the final result the regular three-dimensional model is slightly modified, the planes of the benzene rings being apparently turned from 13° to 16° out of the symmetrical position.


2001 ◽  
Vol 2 (1) ◽  
pp. 1-26
Author(s):  
Chris A.M. Hermans

The author gives an outline for a dynamic model of identity of religiously affiliated schools. The model is composed of three dimensions: the different actors in the school, the educational aims, content and processes and the socio-cultural context that influences the first two dimensions. The dynamic in this model is caused by the interaction of the variables in the three dimensions. Against the background of this model, the contributions of this issue on identity are outlined.


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