Scaling Invariance of Sports Sex Gap

The controversy over the evolution of sex gap in sports stems from the reported that women’s performance will 1 day overtake men’s in the journal Nature. After debate, the recent studies suggest that the sports sex gap has been stable for a long time, due to insurmountable physiological differences. To find a mathematical model that accurately describes this stable gap, we analyze the best annual records of men and women in 25 events from 1992 to 2017, and find that power-law relationship could be acted as the best choice, with an R-squares as high as 0.999 (p ≤ 0.001). Then, based on the power law model, we use the records of men in 2018 to predict the performance of women in that year and compare them with real records. The results show that the deviation rate of the predicted value is only about 2.08%. As a conclusion, it could be said that there is a constant sex gap in sports, and the records of men and women evolve in parallel. This finding could serve as another quantitative rule in biology.

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A Mathematical Model on Social Integration Explaining Global Suicide Rate Among Men and Women

Recoletos Multidisciplinary Research Journal ◽

10.32871/rmrj1402.01.06 ◽

2014 ◽

Vol 2 (1) ◽

pp. 49-54

Author(s):

Mark Borres ◽

◽

Jergen Orias ◽

Alvin Mercado ◽

◽

...

Keyword(s):

Mathematical Model ◽

Social Integration ◽

Suicide Rate ◽

Men And Women

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Power law model. Goodness-of-fit tests and estimation methods

10.3403/30249080 ◽

2013 ◽

Keyword(s):

Power Law ◽

Goodness Of Fit ◽

Estimation Methods ◽

Power Law Model ◽

Goodness Of Fit Tests

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Polyconvex hyperelastic modeling of rubberlike materials

Journal of the Brazilian Society of Mechanical Sciences and Engineering ◽

10.1007/s40430-021-03062-w ◽

2021 ◽

Vol 43 (7) ◽

Author(s):

Cyprian Suchocki ◽

Stanisław Jemioło

Keyword(s):

Experimental Data ◽

Power Law ◽

Curve Fitting ◽

Constitutive Relations ◽

Data Sets ◽

Power Law Model ◽

Stored Energy ◽

Data Approximation ◽

Exponential Power ◽

Hyperelastic Models

AbstractIn this work a number of selected, isotropic, invariant-based hyperelastic models are analyzed. The considered constitutive relations of hyperelasticity include the model by Gent (G) and its extension, the so-called generalized Gent model (GG), the exponential-power law model (Exp-PL) and the power law model (PL). The material parameters of the models under study have been identified for eight different experimental data sets. As it has been demonstrated, the much celebrated Gent’s model does not always allow to obtain an acceptable quality of the experimental data approximation. Furthermore, it is observed that the best curve fitting quality is usually achieved when the experimentally derived conditions that were proposed by Rivlin and Saunders are fulfilled. However, it is shown that the conditions by Rivlin and Saunders are in a contradiction with the mathematical requirements of stored energy polyconvexity. A polyconvex stored energy function is assumed in order to ensure the existence of solutions to a properly defined boundary value problem and to avoid non-physical material response. It is found that in the case of the analyzed hyperelastic models the application of polyconvexity conditions leads to only a slight decrease in the curve fitting quality. When the energy polyconvexity is assumed, the best experimental data approximation is usually obtained for the PL model. Among the non-polyconvex hyperelastic models, the best curve fitting results are most frequently achieved for the GG model. However, it is shown that both the G and the GG models are problematic due to the presence of the locking effect.

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Unsteady thermal Maxwell power law nanofluid flow subject to forced thermal Marangoni Convection

Scientific Reports ◽

10.1038/s41598-021-86865-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Muhammad Jawad ◽

Anwar Saeed ◽

Taza Gul ◽

Zahir Shah ◽

Poom Kumam

Keyword(s):

Relaxation Time ◽

Power Law ◽

Marangoni Convection ◽

Power Law Model ◽

Analysis Method ◽

Stretching Surface ◽

Nanofluid Flow ◽

Welan Gum ◽

Homotopy Analysis ◽

Power Law Nanofluid

AbstractIn the current work, the unsteady thermal flow of Maxwell power-law nanofluid with Welan gum solution on a stretching surface has been considered. The flow is also exposed to Joule heating and magnetic effects. The Marangoni convection equation is also proposed for current investigation in light of the constitutive equations for the Maxwell power law model. For non-dimensionalization, a group of similar variables has been employed to obtain a set of ordinary differential equations. This set of dimensionless equations is then solved with the help of the homotopy analysis method (HAM). It has been established in this work that, the effects of momentum relaxation time upon the thickness of the film is quite obvious in comparison to heat relaxation time. It is also noticed in this work that improvement in the Marangoni convection process leads to a decline in the thickness of the fluid’s film.

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Research on cargo-loading optimization based on genetic and fuzzy integration

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189669 ◽

2021 ◽

Vol 40 (4) ◽

pp. 8493-8500

Author(s):

Yanwei Du ◽

Feng Chen ◽

Xiaoyi Fan ◽

Lei Zhang ◽

Henggang Liang

Keyword(s):

Genetic Algorithm ◽

Mathematical Model ◽

Three Dimensional ◽

Distribution Center ◽

Long Time ◽

Low Efficiency ◽

Decision Making Model ◽

The Mathematical Model ◽

Loading Scheme

With the increase of the number of loaded goods, the number of optional loading schemes will increase exponentially. It is a long time and low efficiency to determine the loading scheme with experience. Genetic algorithm is a search heuristic algorithm used to solve optimization in the field of computer science artificial intelligence. Genetic algorithm can effectively select the optimal loading scheme but unable to utilize weight and volume capacity of cargo and truck. In this paper, we propose hybrid Genetic and fuzzy logic based cargo-loading decision making model that focus on achieving maximum profit with maximum utilization of weight and volume capacity of cargo and truck. In this paper, first of all, the components of the problem of goods stowage in the distribution center are analyzed systematically, which lays the foundation for the reasonable classification of the problem of goods stowage and the establishment of the mathematical model of the problem of goods stowage. Secondly, the paper abstracts and defines the problem of goods loading in distribution center, establishes the mathematical model for the optimization of single car three-dimensional goods loading, and designs the genetic algorithm for solving the model. Finally, Matlab is used to solve the optimization model of cargo loading, and the good performance of the algorithm is verified by an example. From the performance evaluation analysis, proposed the hybrid system achieve better outcomes than the standard SA model, GA method, and TS strategy.

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X-ray Properties of 3C 111: Separation of Primary Nuclear Emission and Jet Continuum

Universe ◽

10.3390/universe6110219 ◽

2020 ◽

Vol 6 (11) ◽

pp. 219

Author(s):

Elena Fedorova ◽

B.I. Hnatyk ◽

V.I. Zhdanov ◽

A. Del Popolo

Keyword(s):

Accretion Disk ◽

Power Law ◽

Line Emission ◽

High Energy ◽

Power Law Model ◽

X Ray ◽

Additional Information ◽

Observational Dataset ◽

Simple Power ◽

Photon Index

3C111 is BLRG with signatures of both FSRQ and Sy1 in X-ray spectrum. The significant X-ray observational dataset was collected for it by INTEGRAL, XMM-Newton, SWIFT, Suzaku and others. The overall X-ray spectrum of 3C 111 shows signs of a peculiarity with the large value of the high-energy cut-off typical rather for RQ AGN, probably due to the jet contamination. Separating the jet counterpart in the X-ray spectrum of 3C 111 from the primary nuclear counterpart can answer the question is this nucleus truly peculiar or this is a fake “peculiarity” due to a significant jet contribution. In view of this question, our aim is to estimate separately the accretion disk/corona and non-thermal jet emission in the 3C 111 X-ray spectra within different observational periods. To separate the disk/corona and jet contributions in total continuum, we use the idea that radio and X-ray spectra of jet emission can be described by a simple power-law model with the same photon index. This additional information allows us to derive rather accurate values of these contributions. In order to test these results, we also consider relations between the nuclear continuum and the line emission.

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Using Old Photographs in Interviews: Some Cautionary Notes About Silences in Fieldwork

History in Africa ◽

10.2307/3171821 ◽

1990 ◽

Vol 17 ◽

pp. 327-334 ◽

Cited By ~ 1

Author(s):

Bill Bravman

Keyword(s):

Power Relations ◽

Men And Women ◽

Cultural Assumptions ◽

The People ◽

Taita Hills ◽

National Archives ◽

Long Time ◽

Photo Collection ◽

Image Production ◽

To Come

In September 1987, early in my research at the Kenya National Archives, I came across a collection of photographs taken by a British missionary during the 1920s and early 1930s. The collection contained nearly 250 photos of the terrain and people of Kenya's Taita Hills, where I would soon be going for my fieldwork. I pored over the photo collection for a long time, and had reproductions made of twenty-five shots. The names of those pictured had been recorded in the photo album's captions. Many of the names were new to me, though a few WaTaita of the day who had figured prominently in the archival records were also captured on film. When I moved on to Taita in early 1988,1 took the photographs with me. Since I would be interviewing men and women old enough either to remember or be contemporaries of the people in the pictures, I planned to show the photos during the interviews. At first I was simply curious about who some of the people pictured were, but my curiosity quickly evolved into a more ambitious plan. I decided to try using the photographs as visual prompts to get people to speak more expansively than they otherwise might about their lives and their experiences.In the event, I learned that using the photographs in interviews involved many more complexities than I had envisaged in my initial enthusiasm. I found that I had to alter the expectations and techniques I took to Taita, and feel out some of the limitations of working with the photographic medium. I had to recognize the power relations embedded in my presence as a researcher in Taita, in my position as bearer of images from peoples' pasts, and in the photos themselves. I found, too, that I needed to come to grips with a number of issues about the politics of image production, and the historical product of those politics: the bounded, selected images that are photographs. Finally, I had to address some of my own cultural assumptions about photography and how people respond to pictures, assumptions that my informants did not necessarily share.

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Dynamics of Developing Laminar Non-Newtonian Falling Liquid Films With Free Surface

Journal of Applied Mechanics ◽

10.1115/1.3424229 ◽

1978 ◽

Vol 45 (1) ◽

pp. 19-24 ◽

Cited By ~ 20

Author(s):

V. Narayanamurthy ◽

P. K. Sarma

Keyword(s):

Liquid Film ◽

Power Law ◽

Mathematical Formulation ◽

Liquid Films ◽

Interfacial Shear ◽

Newtonian Liquid ◽

Power Law Model ◽

Falling Liquid Film ◽

Falling Liquid Films ◽

Special Case

The dynamics of accelerating, laminar non-Newtonian falling liquid film is analytically solved taking into account the interfacial shear offered by the quiescent gas adjacent to the liquid film under adiabatic conditions of both the phases. The results indicate that the thickness of the liquid film for the assumed power law model of the shear deformation versus the shear stress is influenced by the index n, the modified form of (Fr/Re). The mathematical formulation of the present analysis enables to treat the problem as a general type from which the special case for Newtonian liquid films can be derived by equating the index in the power law to unity.

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