physical quantity
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2022 ◽  
Vol 924 (2) ◽  
pp. 41
Author(s):  
Bernard J. Vasquez ◽  
Sergei A. Markovskii ◽  
Charles W. Smith

Abstract Three-dimensional hybrid kinetic simulations are conducted with particle protons and warm fluid electrons. Alfvénic fluctuations initialized at large scales and with wavevectors that are highly oblique with respect to the background magnetic field evolve into a turbulent energy cascade that dissipates at proton kinetic scales. Accompanying the proton scales is a spectral magnetic helicity signature with a peak in magnitude. A series of simulation runs are made with different large-scale cross helicity and different initial fluctuation phases and wavevector configurations. From the simulations a so-called total magnetic helicity peak is evaluated by summing contributions at a wavenumber perpendicular to the background magnetic field. The total is then compared with the reduced magnetic helicity calculated along spacecraft-like trajectories through the simulation box. The reduced combines the helicity from different perpendicular wavenumbers and depends on the sampling direction. The total is then the better physical quantity to characterize the turbulence. On average the ratio of reduced to total is 0.45. The total magnetic helicity and the reduced magnetic helicity show intrinsic variability based on initial fluctuation conditions. This variability can contribute to the scatter found in the observed distribution of solar wind reduced magnetic helicity as a function of cross helicity.


Author(s):  
Aleksandr Nedostup ◽  
Alexey Olegovich Razhev ◽  
Pavel Nasenkov ◽  
Karina Konovalova ◽  
Alexey Aleksandrovich Bykov ◽  
...  

The force performance of trawl systems directly depends on the work performed by these forces.The mechanical work of a trawl system is a physical quantity that depends on the vectors of force (hydrodynamic, tension, compression, etc.) and displacement. Thermodynamic work is the amount of energy transmitted or received by the trawl system by changing its external parameters. There is also the work of the forces of the electrostatic field when the charge moves from one point of the field to another. Equations are obtained for ideal flexible steel ropes and rope-rope products, characterizing the direct proportionality of the ratio of the productivity of forces that are directed perpendicular to each other and depend on the Poisson's ratio and the constructive elongation of ideal flexible steel ropes and cordage products. The ratio of the capacities of the forces or the ratio of the moduli of elasticity in the transverse and longitudinal directions, which arise when steel ropes and rope-rope products are stretched, are inversely proportional to the square of the coefficient k connecting the elongation λ, Poisson's ratio μ and the relative elongation ε at a constant volume of the product and its mass. There has been described an example of stretching perfectly flexible steel ropes and cordage. Such constructive parameters as lay, the number of strands, wire and fiber thickness, type of weaving were not taken into account.


2021 ◽  
Vol 15 (1) ◽  
pp. 13
Author(s):  
Qing Li

An approximate calculation of the spatial characteristics on finite range is required, so one quantitative continuum represents the accumulation of infinite great quantities is artificially divided it into smaller and camparable parts in which calculus operation can be applied .This operation is defined as Theorem 1 in which infinity is not involved, there is a camparable finity is constantly (forever) approaching and not reaching infinity, and only staying within a finite range. Theorem 1 can exist in this paper as a new mathematical basis for physics. Because the essence of all physical quantities is size comparison, and the size comparison relation of matter can only be space/time, so relation formula space/time is the only expression of the concept of matter, all physical quantities are applicable to this expression, each different physical quantity is a multi-dimensional representation of this expression. A new mass energy formula is aslo derived from this paper.


2021 ◽  
Vol 81 (11) ◽  
Author(s):  
Richard D. Ball ◽  
Stefano Forte ◽  
Roy Stegeman

AbstractWe study the correlation between different sets of parton distributions (PDFs). Specifically, viewing different PDF sets as distinct determinations, generally correlated, of the same underlying physical quantity, we examine the extent to which the correlation between them is due to the underlying data. We do this both for pairs of PDF sets determined using a given fixed methodology, and between sets determined using different methodologies. We show that correlations have a sizable component that is not due to the underlying data, because the data do not determine the PDFs uniquely. We show that the data-driven correlations can be used to assess the efficiency of methodologies used for PDF determination. We also show that the use of data-driven correlations for the combination of different PDFs into a joint set can lead to inconsistent results, and thus that the statistical combination used in constructing the widely used PDF4LHC15 PDF set remains the most reliable method.


2021 ◽  
Author(s):  
Youpeng Zhang ◽  
Haodong Wang ◽  
Jianying Zhong ◽  
Shengwu Tan ◽  
Yongqi Yao ◽  
...  

2021 ◽  
Author(s):  
Vasil Penchev

Husserl’s “noema” and “noesis” are main concepts in phenomenology able to represent its originality. Following the trace of a recent paper, its formal and philosophical approach is extended to both correlative notions, in the present article. They are able to reveal the genesis of the world from consciousness in a transcendental method relevant to Husserl, but furthermore described formally as a process of how subjective temporality appears being isomorphic to objective temporality of the “world by itself” (an abstraction meaning it out of consciousness or transcendental consciousness): thus, it shares the same mathematical structure, which is embodied in the physical process of decoherence by the physical quantity of quantum information. The temporal world is able to appear naturally . The same process translated by formal and mathematical tools as interpreted in terms of “noema”, “noesis”, or transcendental consciousness is isomorphic to how “Self” appears in virtue of transcendental consciousness.


Author(s):  
Qing Li

An approximate calculation of the spatial characteristics on finite range is required, so one quantitative continuum represents the accumulation of infinite great quantities is artificially divided it into smaller and camparable parts in which calculus operation can be applied .This operation is defined as Theorem 1 in which infinity is not involved, there is a camparable finity is constantly (forever) approaching and not reaching infinity, and only staying within a finite range. Theorem 1 can exist in this paper as a new mathematical basis for physics. Because the essence of all physical quantities is size comparison, and the size comparison relation of matter can only be space/time, so relation formula space/time is the only expression of the concept of matter, all physical quantities are applicable to this expression, each different physical quantity is a multi-dimensional representation of this expression. A new mass energy formula is aslo derived from this paper.


2021 ◽  
Vol 9 (4) ◽  
pp. 34-40
Author(s):  
Duc Ky Bui ◽  
Ngoc Quynh Nguyen ◽  
Duc Thang Duong ◽  
Ngoc Thiem Le ◽  
Quang Tuan Ho ◽  
...  

Evaluating measurement uncertainty of a physical quantity is a mandatory requirement for laboratories within the recognition ISO/IEC 17025 certification to access reliability of measured results. In this work, the uncertainty of ionizing radiation measurements such as air-kerma, personal dose equivalent Hp(d) was evaluated based on GUM method and Monte Carlo method. An uncertainty propagation software has been developed for evaluation of the measurement uncertainty more convenient.


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