Multifluid plasma equations in terms of hyperbolic octonions

2018 ◽  
Vol 15 (04) ◽  
pp. 1850053 ◽  
Author(s):  
Süleyman Demir ◽  
Erdinç Zeren
Keyword(s):  
Wave Equations ◽  
Relevant Literature ◽  
Single Equation ◽  
Electromagnetic Theory ◽  
Compressible Fluids ◽  
Field Equations ◽  
Proposed Model ◽  
Electromagnetic Behavior ◽  
Linear Gravity ◽  
Multifluid Plasma

Stimulating from the hyperbolic octonionic generalization of the Maxwell-type equations of compressible fluids, an alternative reformulation has been proposed for the analogous multifluid plasma equations. In this paper, using both the fluid and electromagnetic behavior of the plasma, the compact and elegant expressions have been derived in terms of hyperbolic octonions as previously given for electromagnetic theory, linear gravity and fluid mechanics. Using the advantages of proposed model, the field equations of multifluid plasma have been combined in a single equation. Furthermore, the plasma wave equations in terms of generalized vorticity and Lamp vector have been expressed in a form similar to electromagnetic, gravitational counterparts previously given in relevant literature.

scholarly journals Content Dependent Representation Selection Model for Systems Based on MPEG DASH

Electronics ◽  
2021 ◽  
Vol 10 (15) ◽  
pp. 1843
Author(s):  
Jelena Vlaović ◽  
Snježana Rimac-Drlje ◽  
Drago Žagar
Keyword(s):  
Mathematical Model ◽  
Spatial Information ◽  
Relevant Literature ◽  
Video Quality ◽  
Similarity Index ◽  
Video Encoding ◽  
Adaptation Algorithm ◽  
Subjective Testing ◽  
Proposed Model ◽  
The Mathematical Model

A standard called MPEG Dynamic Adaptive Streaming over HTTP (MPEG DASH) ensures the interoperability between different streaming services and the highest possible video quality in changing network conditions. The solutions described in the available literature that focus on video segmentation are mostly proprietary, use a high amount of computational power, lack the methodology, model notation, information needed for reproduction, or do not consider the spatial and temporal activity of video sequences. This paper presents a new model for selecting optimal parameters and number of representations for video encoding and segmentation, based on a measure of the spatial and temporal activity of the video content. The model was developed for the H.264 encoder, using Structural Similarity Index Measure (SSIM) objective metrics as well as Spatial Information (SI) and Temporal Information (TI) as measures of video spatial and temporal activity. The methodology that we used to develop the mathematical model is also presented in detail so that it can be applied to adapt the mathematical model to another type of an encoder or a set of encoding parameters. The efficiency of the segmentation made by the proposed model was tested using the Basic Adaptation algorithm (BAA) and Segment Aware Rate Adaptation (SARA) algorithm as well as two different network scenarios. In comparison to the segmentation available in the relevant literature, the segmentation based on the proposed model obtains better SSIM values in 92% of cases and subjective testing showed that it achieves better results in 83.3% of cases.

Neighborhood Disorder, Urban Stressors, and Street Codes: A Model for Exploring Social Determinants of Life-Course Trajectories

2017 ◽  
Vol 1 (2) ◽  
pp. 89-103 ◽  
Author(s):  
M. Daniel Bennett
Keyword(s):  
Life Course ◽  
Social Determinants ◽  
Relevant Literature ◽  
African American Youth ◽  
Developmental Outcomes ◽  
Neighborhood Disorder ◽  
Proposed Model ◽  
The Social ◽  
Youth And Young Adults ◽  
Health Model

This article reviews relevant literature and proposes a theoretically grounded conceptual model by which to inform, and potentially advance, the exploratory study of the effects of neighborhood disorder on the psychosocial, emotional, and cultural pathways that are thought to influence social and developmental outcomes for African American youth and young adults. Similar to the social determinants of health model which asserts that the distribution of social and economic resources across populations influences differences in health status, the proposed model posits that environment determines social and developmental outcomes and hence life-course trajectories.

Randomness in modified general relativity theory: The stochastic f(R) gravity model

2018 ◽  
Vol 96 (11) ◽  
pp. 1173-1177
Author(s):  
Tomer Shushi
Keyword(s):  
Gravity Field ◽  
Gravity Model ◽  
Gravity Models ◽  
Relativity Theory ◽  
Field Equations ◽  
Important Special Case ◽  
Proposed Model ◽  
Stochastic Space ◽  
Wavefunction Collapse ◽  
New Interpretation

We consider a stochastic modification of the f(R) gravity models, and provide its important properties, including the gravity field equations for the model. We show a prediction in which particles are localized by a system of random gravitational potentials. As an important special case, we investigate a gravity model in the presence of a small stochastic space–time perturbation and provide its gravity field equations. Using the proposed model we examine the stochastic quantum mechanics interpretation, and obtain a novel Schrödinger equation with gravitational potential that is based on diffusion in a gravitational field. Furthermore, we provide a new interpretation to the wavefunction collapse. It seems that the stochastic f(R) gravity model causes decoherence of the spatial superposition state of particles.

scholarly journals Antecedents of absorptive capacity: a new model for developing learning processes

2016 ◽  
Vol 23 (1) ◽  
pp. 77-91 ◽  
Author(s):  
Mohammad Rezaei-Zadeh ◽  
Tamer K Darwish
Keyword(s):  
Absorptive Capacity ◽  
Relevant Literature ◽  
Learning Processes ◽  
Environmental Turbulence ◽  
Content Type ◽  
Proposed Model ◽  
Exploitative Learning ◽  
Modes Of Governance ◽  
Future Work ◽  
Practical Implications

Purpose – The purpose of this paper is to provide an integrated framework to indicate which antecedents of absorptive capacity (AC) influence its learning processes, and to propose testing of this model in future work. Design/methodology/approach – Relevant literature into the antecedents of AC was critically reviewed and analysed with the objective of categorising and explaining the influence of AC on learning processes, including exploratory, transformative and exploitative learning. Findings – By considering the level of learning, the proposed model demonstrates that the antecedents of AC vary, comprising exploratory, transformative and exploitative learning processes. Moreover, this study reveals the complex interplay between the antecedents of AC. Research limitations/implications – The proposed model was developed theoretically, thus pending further empirical validation according to environmental turbulence, knowledge characteristics and modes of governance. This study also urges researchers to explore whether or not the antecedents of AC differ based on organisational outcomes. Practical implications – The model can be put into a testable template for use by researchers. It further guides managers in developing effective processes for learning to use external knowledge. Originality/value – It is the first work to schematically bring together and discuss the antecedents of AC and its influence on learning processes, and further provides a framework capable of facilitating the empirical testing of this nexus.

scholarly journals On electric phenomena in gravitational fields

1927 ◽  
Vol 116 (775) ◽  
pp. 720-735 ◽  
Keyword(s):  
Gravitational Field ◽  
Electromagnetic Waves ◽  
Wave Length ◽  
Gravitational Effect ◽  
Electromagnetic Theory ◽  
Relativity Theory ◽  
Elementary Functions ◽  
Field Equations ◽  
Gravitational Fields ◽  
Particular Solutions

It is a consequence of general relativity that all electromagnetic and optical phenomena are influenced by a gravitational field. Indeed, the first prediction of relativity-theory, namely, the bending of light-rays when they pass near a massive body such as the sun, was a p articular application of this principle. Evidently, therefore, the classical electromagnetic theory must be rewritten in order to take account of the interaction between electromagnetism and gravitation; but beyond laying down general principles, comparatively little progress has been made hitherto in this task, the mathematical difficulties of solving definite electrical problems in a gravitational field being somewhat formidable. The subject is, however, of some interest to atomic physics; for if we assume that the atom has a massive nucleus with electrons in its immediate neighbourhood, the behaviour of such electrons (especially with regard to radiation) will be affected by the gravitational field of the nucleus. In the present paper two kinds of gravitational field are considered, namely, the field due to a single attracting centre ( i, e ., the field whose metric was discovered by Schwarzschild) and a limiting form of it. Within these gravita­tional fields we suppose electromagnetic fields to exist. Strictly speaking, the electromagnetic field has itself a gravitational effect, i.e. , it changes the metric everywhere; but this effect is in general; small, and we shall treat the ideal case in which it is ignored, so we shall suppose the metric to be simply that of the gravitational field originally postulated. The general equations of the electro­magnetic field are obtained, and particular solutions are found, which are the analogues of well-known particular solutions in the classical electromagnetic theory; notably the fields due to electrons at rest, electrostatic fields in general, and spherical electromagnetic waves. The results of the investigation are for the most part expressible only in terms of Bessel functions and certain new functions which are introduced; but in some interesting cases the electro­magnetic phenomena can be represented in term s of elementary functions, as, for instance, the electric field due to an electron in a quasi-uniform gravitational field (equations (15) and (19) below) and the spherical electromagnetic waves of short wave-length about a gravitating centre (equation (43) below).

A Proposed Model for the Thermal Conductivity of Dry And Water-Saturated Tuff

1983 ◽  
Vol 26 ◽  
Author(s):  
M. Moss ◽  
G. M. Haseman
Keyword(s):  
Thermal Conductivity ◽  
Geometric Mean ◽  
Test Site ◽  
Single Equation ◽  
Nevada Test Site ◽  
Water Conductivity ◽  
Rock Types ◽  
Proposed Model ◽  
Water Saturated ◽  
Fluid Conductivity

ABSTRACTThe room-temperature thermal conductivities of two kinds of tuff from the Nevada Test Site have been measured on a linear-heat-flow thermal comparator. The results are the basis for an empirical model of the conductivity of these rocks in the dry and water-saturated conditions as a function of porosity. Tuff is one medium being considered for nuclear waste disposal. Devitrified, non-zeolitized tuffs with 6-22% porosity, and non-welded, zeolitized tuffs with 24-35% porosity were examined. The empirical geometric mean model is used to characterize the porosity-dependent thermal conductivity. We consider the rock matrix conductivity and the effective fluid conductivity as adjustable parameters in fitting the model to data for saturated and dehydrated samples, separately. For each rock type, the fitted value of matrix conductivity is the same in both the saturated and dehydrated cases; 2.3 and 1.1 W/(m.K) for the non-zeolitized and zeolitized tuffs, respectively. The fitted values for fluid conductivities are different for the the zeolitized and non-zeolitized tuffs, but the ratio of fitted water conductivity to fitted gas conductivity is very nearly the same for both rock types. This permits the use of a single equation to predict with good accuracy the ratio of saturated to dry rock conductivity.

MEMS Integrated Electro-Fluid-Elastic Modeling for Aerospace Applications

2006 ◽  
Author(s):  
Alessandro Fumagalli ◽  
Giuseppe Quaranta ◽  
Paolo Mantegazza
Keyword(s):  
Jacobian Matrix ◽  
Dynamical Analysis ◽  
Published Data ◽  
Field Equations ◽  
Fully Integrated ◽  
Aerospace Applications ◽  
Integrated Methodology ◽  
Proposed Model ◽  
Elastic Systems ◽  
Good Agreement

MEMS physics is characterized by multi-fields interactions. In this paper, a fully integrated methodology is proposed for dynamical analysis of electro-fluid-elastic systems, typical of MEMS-based microresonators and microswitches. Finite Elements/Volumes Method is used to solve field equations. These are coupled by an opportune procedure of interface between domains, resulting in a nonlinear algebraic differential system of equations describing the system. This is directly integrated in time, becoming fully algebraic, and solved by a Newton technique. Full Jacobian matrix computation results in a very hard task. Analytical block approximation for Jacobian matrix is proposed. Model is validated comparing results with commercial codes and with published data, showing good agreement, high convergence properties and reduced computational efforts.

Sedenionic formulation for the field equations of multifluid plasma

2020 ◽  
pp. 2150040
Author(s):  
Süleyman Demir ◽  
Damla Sümer ◽  
Murat Tanışlı
Keyword(s):  
Fluid Dynamics ◽  
Wave Equation ◽  
Maxwell Equations ◽  
Mathematical Tool ◽  
Source Terms ◽  
Classical Electromagnetism ◽  
Field Equations ◽  
Multifluid Plasma

In this paper, the multifluid equations of a plasma are reformulated in terms of conic sedenions in order to better reflect the analogies between multifluid plasma equations and Maxwell equations of classical electromagnetism. This formalism also provides us an efficient mathematical tool for unification of equations of fluid dynamics and electromagnetism in a compact and elegant way. Although the presented formulation enables us to express all of the field equations related to different disciplines, a set of Maxwell equations for multifluid plasma is combined into a single sedenionic equation. Moreover, the wave equation with source terms is generalized in a form similar to gravi-electromagnetism counterpart previously derived using this type sedenion.

Analysis of compact stars in logarithmic-corrected R2 gravity

2019 ◽  
Vol 35 (02) ◽  
pp. 1950354 ◽  
Author(s):  
M. Farasat Shamir ◽  
Iffat Fayyaz
Keyword(s):  
Graphical Representation ◽  
Stellar Model ◽  
Compact Stars ◽  
Energy Conditions ◽  
Einstein Field Equations ◽  
Field Equations ◽  
Logarithmic Corrections ◽  
Proposed Model ◽  
Physical Tests ◽  
Surface Redshift

We discuss the existence of compact stars in the context of [Formula: see text] gravity model, where additional logarithmic corrections are assumed. Here, [Formula: see text] is the Ricci scalar and [Formula: see text], [Formula: see text] are constant values. Further, the compact stars are considered to be anisotropic in nature, due to the spherical symmetry and high density. For this purpose, we derive the Einstein field equations by considering Krori–Barua spacetime. For our proposed model, the physical acceptability is verified by employing several physical tests like the energy conditions, Herrera cracking concept and stability condition. In addition to this, we also discuss some important properties such as mass–radius relation, surface redshift and the speed of sound are analyzed. Our results are compared with observational stellar mass data, namely, 4U 1820-30, Cen X-3, EXO 1785-248 and LMC X-4. The graphical representation of obtained solutions provide strong evidences for more realistic and viable stellar model.

Characteristics of the Responsible Entrepreneur

2019 ◽  
pp. 65-131
Keyword(s):  
Theoretical Model ◽  
Relevant Literature ◽  
Entrepreneurial Education ◽  
The Core ◽  
Entrepreneurial Skills ◽  
Detailed Explanation ◽  
Proposed Model ◽  
Entrepreneurial Action

In the chapter, the authors provide a detailed explanation of their proposed model. In doing so, they analyze each set of entrepreneurial skills separately. For each skill, they present the relevant literature and the positioning in our theoretical model. The chapter represents the core of the study. Once the theoretical reference paradigms and the underlying literature have been defined, it is possible to start developing the theoretical model to undertake entrepreneurial education. The goal of this model is not to provide a simple list of skills but to develop, starting from a philosophical key and then moving to a psychological direction, a system to understand what should be the skills, attitudes, and meta skills to make sure that entrepreneurial action manifests itself and is successful.

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