scholarly journals Phase Transition in Modified Newtonian Dynamics (MONDian) Self-Gravitating Systems

Entropy ◽  
2021 ◽  
Vol 23 (9) ◽  
pp. 1158
Author(s):  
Mohammad Hossein Zhoolideh Zhoolideh Haghighi ◽  
Sohrab Rahvar ◽  
Mohammad Reza Rahimi Rahimi Tabar
Keyword(s):  
Phase Transition ◽  
Binary Systems ◽  
Dimensional Space ◽  
Gravitational Interaction ◽  
Three Dimensional ◽  
Physical Parameters ◽  
Canonical Systems ◽  
Modified Newtonian Dynamics ◽  
Newtonian Dynamics ◽  
Gravitating Systems

We study the statistical mechanics of binary systems under the gravitational interaction of the Modified Newtonian Dynamics (MOND) in three-dimensional space. Considering the binary systems in the microcanonical and canonical ensembles, we show that in the microcanonical systems, unlike the Newtonian gravity, there is a sharp phase transition, with a high-temperature homogeneous phase and a low-temperature clumped binary one. Defining an order parameter in the canonical systems, we find a smoother phase transition and identify the corresponding critical temperature in terms of the physical parameters of the binary system.

A Miniature Four-Microphone Array for Two-Dimensional Direction-of-Arrival Estimation Based on Biomimetic Time-Delay Magnification

2019 ◽  
Vol 141 (2) ◽  
Author(s):  
Ling Liu ◽  
Ming Yang ◽  
Yaqiong Zhang ◽  
Xinlei Zhu ◽  
Na Ta ◽  
...  
Keyword(s):  
Time Delay ◽  
Microphone Array ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Coupled System ◽  
Direction Of Arrival ◽  
Physical Parameters ◽  
Two Dimensional ◽  
Coupling Algorithm ◽  
Three Dimensional Space

A miniature microphone array based on interaural time difference (ITD) is designed. This array contains four microphones with certain arrangement and aims for two-dimensional (azimuth and elevation) direction-of-arrival (DOA) estimation in the whole three-dimensional space. The array can be small because it uses a coupling algorithm that magnifies the time delay between the signals received by every two microphones. The coupling algorithm is built according to a pairwise-coupled multidimensional mechanical model inspired by the ears of the tiny parasitoid fly Ormia ochracea. It was verified that the time-delay magnification can be independent of the incident angle when the parameters in the model satisfy specific relationships. This paper further investigates the multidimensional coupled system and advocates to realize the magnification mechanism in algorithm, where the physical parameters can change according to sound frequency to ensure the time-delay magnification. Moreover, the arrangement of microphones is specially designed to help the array to achieve similar measuring accuracy for all directions in the three-dimensional space. Corresponding signal process procedures are also provided. Simulations that use such an array to estimate the azimuth and elevation angles of sound source are performed via general cross-correlation (GCC) method. Results verify the feasibility of the microphone array and show that the accuracy of the estimation increases after the signals are processed by the coupled system.

Regional Estimation of Block Oilfield Rock Physical Parameters

2013 ◽  
Vol 734-737 ◽  
pp. 1425-1428
Author(s):  
Lin Cong ◽  
Yang Liu ◽  
Wen Long Li ◽  
Hai Ou Fang
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Fault Model ◽  
Surface Model ◽  
Physical Parameters ◽  
Model Surface ◽  
Development Goals ◽  
Drilling Core ◽  
Rock Parameters ◽  
Three Dimensional Space

Based on getting block oilfield original drilling core data, the study established a geological physical parameters database and visual geological model of block oilfield, including block areas model, fault model, surface model and so on, by choosing several block oilfield oil parameters and using geological sections. The paper established block model by using hexahedral subdivision skills, estimated three-dimensional space physical parameters by using geostatistics theory and constraints of block areas and faults. It got block oilfield rock parameters spatial distribution and supplied a effective method to find oil rich regions and reach rolling development goals.

On the method for the analysis of compulsive phase mixing and its application in cosmogony

2021 ◽  
pp. 83-88
Author(s):  
S. N. NURITDINOV ◽  
A. A. MUMINOV ◽  
F. U. BOTIROV
Keyword(s):  
Phase Space ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Volume Element ◽  
Numerical Calculations ◽  
Complex Nature ◽  
Phase Volume ◽  
Phase Mixing ◽  
Stationary Stochastic Processes ◽  
Gravitating Systems

In this paper, we study the strong non-stationary stochastic processes that take place in the phase space of self-gravitating systems at the earlier non-stationary stage of their evolution. The numerical calculations of the compulsive phase mixing process were carried out according to the model of chaotic impacts, where the initially selected phase volume experiences random pushes that are of a diverse and complex nature. The application of the method for studying random impacts on a volume element in the case of three-dimensional space is carried out.

scholarly journals Relationship between three-dimensional velocity of filament eruptions and CME association

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Daikichi Seki ◽  
Kenichi Otsuji ◽  
Takako T. Ishii ◽  
Ayumi Asai ◽  
Kiyoshi Ichimoto
Keyword(s):  
Kinetic Energy ◽  
Velocity Vector ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Space Environment ◽  
Physical Parameters ◽  
Filament Length ◽  
Filament Eruption ◽  
The Earth ◽  
Three Dimensional Space

AbstractIt is widely recognised that filament disappearances or eruptions are frequently associated with Coronal Mass Ejections (CMEs). Since CMEs are a major source of disturbances of the space environment surrounding the Earth, it is important to investigate these associations in detail for the better prediction of CME occurrence. However, the proportion of filament disappearances associated with CMEs is under debate. The estimates range from $$\sim$$ ∼  10 to $$\sim$$ ∼  90% and could be affected by the manners to select the events. In this study, we aim to reveal what parameters control the association between filament eruptions and CMEs. We analysed the relationships between CME associations and the physical parameters of filaments including their length, maximum ascending velocity, and direction of eruptions using 28 events of filament eruptions observed in H$$\alpha$$ α . We found that the product of the maximum radial velocity and the filament length is well correlated with the CME occurrence. If the product is larger than $$8.0 \times 10^{6}$$ 8.0 × 10 6 $$\text {km}^{2}$$ km 2 $$\text {s}^{-1}$$ s - 1 , the filament will become a CME with a probability of 93%, and if the product is smaller than this value, it will not become a CME with a probability of 100%. We suggest a kinetic-energy threshold above which filament eruptions are associated with CMEs. Our findings also suggest the importance of measuring the velocity vector of filament eruption in three-dimensional space for the better prediction of CME occurrence.

scholarly journals Geometrothermodynamics of black hole binary systems

2020 ◽  
Vol 29 (08) ◽  
pp. 2050053 ◽  
Author(s):  
Hernando Quevedo ◽  
María N. Quevedo ◽  
Alberto Sánchez
Keyword(s):  
Phase Transition ◽  
Black Holes ◽  
Binary System ◽  
Binary Systems ◽  
Contact Structure ◽  
Spatial Distance ◽  
Physical Parameters ◽  
Transition Structure ◽  
Equilibrium Conditions ◽  
Black Hole Binary

We study a stationary and axisymmetric binary system composed of two identical Kerr black holes, whose physical parameters satisfy the Smarr thermodynamic formula. Then, we use the formalism of geometrothermodynamics to show that the spatial distance between the black holes must be considered as a thermodynamic variable. We investigate the main thermodynamic properties of the system by using the contact structure of the phase-space, which generates the first law of thermodynamics and the equilibrium conditions. The phase transition structure of the system is investigated through the curvature singularities of the equilibrium space. It is shown that the thermodynamic and stability properties and the phase transition structure of the binary system strongly depend on the distance between the black holes.

Some Results of the Spectroscopic Study of Four Close Binary Systems of Early Spectral Types

1965 ◽  
Vol 5 ◽  
pp. 120-130
Author(s):  
T. S. Galkina
Keyword(s):  
Spectroscopic Study ◽  
Spectral Type ◽  
Spectroscopic Investigation ◽  
Binary Systems ◽  
Quantitative Information ◽  
Close Binary ◽  
Physical Parameters ◽  
Absorption And Emission ◽  
Close Binary Systems ◽  
Quantitative Estimates

It is necessary to have quantitative estimates of the intensity of lines (both absorption and emission) to obtain the physical parameters of the atmosphere of components.Some years ago at the Crimean observatory we began the spectroscopic investigation of close binary systems of the early spectral type with components WR, Of, O, B to try and obtain more quantitative information from the study of the spectra of the components.

Three Dimensional structure and organization of diploid chromosomes by optical section microscopy

1987 ◽  
Vol 45 ◽  
pp. 633-635
Author(s):  
David A. Agard ◽  
Yasushi Hiraoka ◽  
John W. Sedat
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Developmental State ◽  
Mitotic Cell ◽  
Biological Properties ◽  
Dimensional Structure ◽  
Specific Gene ◽  
Three Dimensional Structure ◽  
Complementary Techniques ◽  
Dynamic Structures

In an effort to understand the complex relationship between structure and biological function within the nucleus, we have embarked on a program to examine the three-dimensional structure and organization of Drosophila melanogaster embryonic chromosomes. Our overall goal is to determine how DNA and proteins are organized into complex and highly dynamic structures (chromosomes) and how these chromosomes are arranged in three dimensional space within the cell nucleus. Futher, we hope to be able to correlate structual data with such fundamental biological properties as stage in the mitotic cell cycle, developmental state and transcription at specific gene loci.Towards this end, we have been developing methodologies for the three-dimensional analysis of non-crystalline biological specimens using optical and electron microscopy. We feel that the combination of these two complementary techniques allows an unprecedented look at the structural organization of cellular components ranging in size from 100A to 100 microns.

Diffraction contrast of dislocations in icosahedral quasicrystals

1990 ◽  
Vol 48 (4) ◽  
pp. 454-455
Author(s):  
K. Urban ◽  
Z. Zhang ◽  
M. Wollgarten ◽  
D. Gratias
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Complete Characterization ◽  
Extinction Condition ◽  
Burgers Vector ◽  
Diffraction Contrast ◽  
Lattice Geometry ◽  
Reference Space ◽  
Icosahedral Quasicrystals ◽  
The One

Recently dislocations have been observed by electron microscopy in the icosahedral quasicrystalline (IQ) phase of Al65Cu20Fe15. These dislocations exhibit diffraction contrast similar to that known for dislocations in conventional crystals. The contrast becomes extinct for certain diffraction vectors g. In the following the basis of electron diffraction contrast of dislocations in the IQ phase is described. Taking account of the six-dimensional nature of the Burgers vector a “strong” and a “weak” extinction condition are found.Dislocations in quasicrystals canot be described on the basis of simple shear or insertion of a lattice plane only. In order to achieve a complete characterization of these dislocations it is advantageous to make use of the one to one correspondence of the lattice geometry in our three-dimensional space (R3) and that in the six-dimensional reference space (R6) where full periodicity is recovered . Therefore the contrast extinction condition has to be written as gpbp + gobo = 0 (1). The diffraction vector g and the Burgers vector b decompose into two vectors gp, bp and go, bo in, respectively, the physical and the orthogonal three-dimensional sub-spaces of R6.

Flavin radicals, conformational sampling and robust design principles in interprotein electron transfer: the trimethylamine dehydrogenase-electron-transferring flavoprotein complex

2004 ◽  
Vol 71 ◽  
pp. 1-14
Author(s):  
David Leys ◽  
Jaswir Basran ◽  
François Talfournier ◽  
Kamaldeep K. Chohan ◽  
Andrew W. Munro ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Kinetic Studies ◽  
Molecular Assembly ◽  
Conformational Sampling ◽  
Trimethylamine Dehydrogenase ◽  
Key Residues ◽  
Electron Transferring Flavoprotein ◽  
Electron Transfer Complex

TMADH (trimethylamine dehydrogenase) is a complex iron-sulphur flavoprotein that forms a soluble electron-transfer complex with ETF (electron-transferring flavoprotein). The mechanism of electron transfer between TMADH and ETF has been studied using stopped-flow kinetic and mutagenesis methods, and more recently by X-ray crystallography. Potentiometric methods have also been used to identify key residues involved in the stabilization of the flavin radical semiquinone species in ETF. These studies have demonstrated a key role for 'conformational sampling' in the electron-transfer complex, facilitated by two-site contact of ETF with TMADH. Exploration of three-dimensional space in the complex allows the FAD of ETF to find conformations compatible with enhanced electronic coupling with the 4Fe-4S centre of TMADH. This mechanism of electron transfer provides for a more robust and accessible design principle for interprotein electron transfer compared with simpler models that invoke the collision of redox partners followed by electron transfer. The structure of the TMADH-ETF complex confirms the role of key residues in electron transfer and molecular assembly, originally suggested from detailed kinetic studies in wild-type and mutant complexes, and from molecular modelling.

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