scholarly journals Local-solution approach to quasistatic rate-independent mixed-mode delamination

2015 ◽  
Vol 25 (07) ◽  
pp. 1337-1364 ◽  
Author(s):  
Tomáš Roubíček ◽  
Christos G. Panagiotopoulos ◽  
Vladislav Mantič
Keyword(s):  
Mixed Mode ◽  
Solution Concept ◽  
Adhesive Contact ◽  
Mathematical Methods ◽  
Solution Approach ◽  
Homogeneous Potential ◽  
Internal Parameters ◽  
Contact Models ◽  
Local Solutions ◽  
The One

The model of quasistatic rate-independent evolution of a delamination at small strains in the so-called mixed mode, i.e. distinguishing opening (Mode I) from shearing (Mode II), devised in [Delamination and adhesive contact models and their mathematical analysis and numerical treatment, Chap. 9, in Mathematical Methods and Models in Composites, ed. V. Mantič (Imperial College Press, 2014), pp. 349–400; and in Quasistatic mixed-mode delamination model, Discrete Contin. Dynam. Syst. Ser. S 6 (2013) 591–610], is rigorously analyzed in the context of a concept of stress-driven local solutions. The model has separately convex stored energy and is associative, namely the one-homogeneous potential of dissipative forces driving the delamination depends only on rates of internal parameters. An efficient fractional-step-type semi-implicit discretization in time is shown to converge to (specific, stress-driven like) local solutions that may approximately obey the maximum-dissipation principle. Making still a spatial discretization, this convergence as well as relevancy of such solution concept are demonstrated on a nontrivial two-dimensional example.

scholarly journals Two adhesive-contact models for quasistatic mixed-mode delamination problems

2018 ◽  
Vol 145 ◽  
pp. 18-33 ◽  
Author(s):  
Christos G. Panagiotopoulos ◽  
Vladislav Mantič ◽  
Tomáš Roubíček
Keyword(s):  
Mixed Mode ◽  
Adhesive Contact ◽  
Contact Models

scholarly journals Physical and Mathematical Fluid Mechanics

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2199
Author(s):  
Markus Scholle
Keyword(s):  
Fluid Mechanics ◽  
Continuum Hypothesis ◽  
Equations Of Motion ◽  
Local Equilibrium ◽  
Physical Modelling ◽  
Mathematical Methods ◽  
Open Questions ◽  
Software Codes ◽  
The One ◽  
The Continuum

Fluid mechanics has emerged as a basic concept for nearly every field of technology. Despite there being a well-developed mathematical theory and available commercial software codes, the computation of solutions of the governing equations of motion is still challenging, especially due to the nonlinearity involved, and there are still open questions regarding the underlying physics of fluid flow, especially with respect to the continuum hypothesis and thermodynamic local equilibrium. The aim of this Special Issue is to reference recent advances in the field of fluid mechanics both in terms of developing sophisticated mathematical methods for finding solutions of the equations of motion, on the one hand, and on novel approaches to the physical modelling beyond the continuum hypothesis and thermodynamic local equilibrium, on the other.

scholarly journals ON THE CHACTERISTIC NUMBERS OF VOTING GAMES

2006 ◽  
Vol 08 (04) ◽  
pp. 643-654 ◽  
Author(s):  
MATHIEU MARTIN ◽  
VINCENT MERLIN
Keyword(s):  
Upper Bound ◽  
Solution Concept ◽  
Voting Games ◽  
Voting Game ◽  
The Stability ◽  
The One

This paper deals with the non-emptiness of the stability set for any proper voting game. We present an upper bound on the number of alternatives which guarantees the non emptiness of this solution concept. We show that this bound is greater than or equal to the one given by Le Breton and Salles (1990) for quota games.

Correspondence between the one-loop three-point vertex and the Y and Δ electric resistor networks

2014 ◽  
Vol 92 (2) ◽  
pp. 131-135 ◽  
Author(s):  
Alfredo Takashi Suzuki
Keyword(s):  
Feynman Diagram ◽  
Hypergeometric Functions ◽  
Analytic Solution ◽  
Minimum Energy ◽  
Electric Circuit ◽  
Mathematical Methods ◽  
Resistor Networks ◽  
Point Vertex ◽  
The One ◽  
Circuit Networks

Different mathematical methods have been applied to obtain the analytic result for the massless triangle Feynman diagram yielding a sum of four linearly independent (LI) hypergeometric functions of two variables F4. This result is not physically acceptable when it is embedded in higher loops, because all four hypergeometric functions in the triangle result have the same region of convergence and further integration means going outside those regions of convergence. We could go outside those regions by using the well-known analytic continuation formulas obeyed by the F4, but there are at least two ways we can do this. Which is the correct one? Whichever continuation one uses, it reduces a number of F4 from four to three. This reduction in the number of hypergeometric functions can be understood by taking into account the fundamental physical constraint imposed by the conservation of momenta flowing along the three legs of the diagram. With this, the number of overall LI functions that enter the most general solution must reduce accordingly. It remains to determine which set of three LI solutions needs to be taken. To determine the exact structure and content of the analytic solution for the three-point function that can be embedded in higher loops, we use the analogy that exists between Feynman diagrams and electric circuit networks, in which the electric current flowing in the network plays the role of the momentum flowing in the lines of a Feynman diagram. This analogy is employed to define exactly which three out of the four hypergeometric functions are relevant to the analytic solution for the Feynman diagram. The analogy is built based on the equivalence between electric resistance circuit networks of types Y and Δ in which flows a conserved current. The equivalence is established via the theorem of minimum energy dissipation within circuits having these structures.

scholarly journals Quasistatic adhesive contact delaminating in mixed mode and its numerical treatment

2013 ◽  
Vol 20 (5) ◽  
pp. 582-599 ◽  
Author(s):  
Martin Kružík ◽  
Christos G Panagiotopoulos ◽  
Tomáš Roubíček
Keyword(s):  
Mixed Mode ◽  
Adhesive Contact ◽  
Numerical Treatment

scholarly journals Criminological Problems of the Digital World (Digital Criminology)

2020 ◽  
Vol 14 (3) ◽  
pp. 423-430
Author(s):  
Anna Serebrennikova
Keyword(s):  
New Technologies ◽  
Technological Development ◽  
Social Consequences ◽  
Mathematical Methods ◽  
Digital World ◽  
The Social ◽  
The One ◽  
Near Future ◽  
Technological Methods ◽  
Industrial Revolutions

The development of information society and the corresponding technologies raises to a new level the tasks of counteracting crimes committed using such technologies, and of minimizing damage from them. The growth in the scale of new types of crime is a cause of worry for the society and the authorities, and especially for criminologists, as the penetration of criminals into the virtual environment and their mastery of new technologies acquire dangerous forms, change criminal motivation and, at the same time, to some extent stimulate the development of information and telecommunication technologies. The growing sophistication of the tasks of preventing and counteracting hi tech crimes makes it necessary to critically assess the current criminological methods and to make an attempt to go beyond the known «common» methods of neo-classical criminology. The development of the digital criminology concept cannot be reduced to an aggregate of pioneer technological methods developed on the basis of mathematical modeling, i.e. computer processing of quantitative and qualitative parameters of crimes, mathematical detection of different dependencies (on time, place and other variables), it could and should be understood in a wider sense: on the one hand, it should influence the new criminological paradigm, and on the other - it should develop within its boundaries. The modern information-analytical sphere in the work of law enforcement bodes includes the use of digital criminological instruments within the programs of crime prevention, mathematical methods of analyzing crimes, profiling, etc. Their aggregate is generally applicable to criminological analysis and prediction, however, it does not have the most cutting edge theoretical basis that corresponds to the tasks of counteracting crimes of the digital world; it is now being formed on the basis of criminological neo-classics, the advances of the social sciences and the humanities, digital criminology. The predictions of new industrial revolutions include a rapid acceleration of the pace of technological development, a systemic transformation of production and management, which will not only stimulate a global rise in the living standards, but will also increase inequality and, consequently, will provide an impetus to crime. These aspects should be taken into consideration when predicting future development of digital criminology, whose theories should be based on the conceptual models of social development of the near future. Social consequences of the predicted new industrial revolutions will inevitably become new common determiners of the crimes of the future, as it always happened in the past.

scholarly journals ANOVA to Compare Three Methods to Track COVID-19 in Nine Countries

2021 ◽  
Author(s):  
◽  
Jorge Juárez-Lucero ◽  
Keyword(s):  
United States ◽  
United Kingdom ◽  
Initial Data ◽  
Nonlinear Regression ◽  
United States Of America ◽  
Mathematical Methods ◽  
Disease Trajectory ◽  
Significant Difference ◽  
The One ◽  
One Way Anova

A new coronavirus denominated first 2019-nCoV and later SARS-CoV-2 was found in Wuhan, China in December of 2019. This paper compares three mathematical methods: nonlinear regression, SIR, and SEIR epidemic models, to track the covid-19 disease in nine countries affected by the SARS-CoV-2 virus, to help epidemiologists to know the disease trajectory, considering initial data in the pandemic, mainly 100 days from the beginning. To evaluate the results obtained with the three methods one-way ANOVA is applied. The average of predicted infected cases with SARS-CoV-2, obtained with the mentioned methods was: for United States of America 1,098,508, followed by Spain with 226,721, Italy with 202,953, France with 183,897 United Kingdom with 182,190, Germany with 159,407, Canada with 58,696, Mexico with 50,366 and Argentina with 4,860 in average. The one-way ANOVA does not show a significant difference among the results of the projected infected cases by SARS-CoV-2, using nonlinear regression, SIR, and SEIR epidemic methods. The above could mean that initially any method can be used to model the pandemic course.

THE CONTRIBUTIONS OF LINGUISTICS TO THE STUDY OF HISTORY IN AFRICA

1997 ◽  
Vol 38 (3) ◽  
pp. 359-391 ◽  
Author(s):  
DEREK NURSE
Keyword(s):  
Historical Development ◽  
Direct Evidence ◽  
Comparative Method ◽  
Historical Events ◽  
The Past ◽  
Language History ◽  
Simple Classification ◽  
Common Activity ◽  
Contact Models ◽  
The One

The work of historical and comparative linguists has long interested African historians. By classifying languages into families, linguists provide models of their historical development that may point to historical events and processes that occurred among peoples speaking those languages. Once classified, linguists can then reconstruct earlier forms of present languages, thus providing direct evidence of words, their meanings and historical influences in the past. Finally, linguists seek to explain innovations that are revealed in their reconstructions by pointing to a combination of internal linguistic developments and different forms of contact that occurred among speakers of different languages.Simple classification, based largely on counting cognate words in related languages (a technique known as lexicostatistics), is still a very common activity, however, and thus the one most historians rely on, but lexicostatistics gives only a very limited, and often deceptive, view of language history. Historians should thus be aware of its limitations as well as the potential of a number of important techniques now employed by linguists, including the Comparative Method, reconstruction of ancestral languages, and contact models.

Feminist Interlegalities and Gender Justice in Sudan: The Debate on CEDAW and Islam

2011 ◽  
Vol 6 (1) ◽  
pp. 25-39 ◽  
Author(s):  
Liv Tønnessen
Keyword(s):  
Gender Equality ◽  
Cultural Relativism ◽  
The Other ◽  
Gender Justice ◽  
State And Society ◽  
Complete Rejection ◽  
Local Solutions ◽  
And Gender ◽  
The One ◽  
Different Cultures

AbstractThe fundamental argument put forward by Islamists, who have ruled Sudan since 1989, for not signing the convention is based on cultural relativism; different cultures provide indigenous and local solutions to their women’s problems. Islam is the solution, not Western feminism. But the Islamists’ failure to ratify CEDAW should not be regarded as a complete rejection of Western feminism, however defined. Through a review of the debate on CEDAW and Islam, this article explores the entanglements of ‘Islamic’ and ‘Western’ normative legal orders. It argues that although Islamist feminists’ discourse deems Western tenets of feminism and gender equality to be unessential to Islamic societies and falsely universalising in its premises, it simultaneously draws upon them in order to demonstrate their ‘alternative’ feminism. By analysing a range of Islamist women’s positions, it becomes apparent that on the one hand they reject CEDAW and gender equality, and on the other promote issues which empower women in the Sudanese state and society. But there are important points of criticism to be made regarding Islamic solutions in a multi-religious and class-divided Sudanese society. Sudanese Islamist women’s claims on behalf of Islamic solutions for Sudanese women can paradoxically be critiqued being as universalising in its premises as so-called Western feminism.

Description and Evaluation of a Simplified Model to Simulate the Optical Behavior of an Angle-Resolved Scattered Light Sensor

2017 ◽  
Vol 17 (2) ◽  
Author(s):  
François M. Torner ◽  
Gerhard Stelzer ◽  
Lukas Anslinger ◽  
Jörg Seewig
Keyword(s):  
Ray Tracing ◽  
Optical Sensors ◽  
Scattered Light ◽  
Computation Time ◽  
Industrial Applications ◽  
Measurement Technology ◽  
Mathematical Methods ◽  
Light Sensor ◽  
Measurement Results ◽  
The One

Scattered light sensors are optical sensors commonly used in industrial applications. They are particularly well suited to characterizing surface roughness. In contrast to most geometric measuring devices, a scattered light sensor measures reflection angles of surfaces according to the principle of the so-called mirror facet model. Surfaces can be evaluated based on the statistical distribution of the surface angles, meaning the gradients. To better understand how the sensor behaves, it is helpful to create a virtual model. Ray-tracing methods are just as conceivable as purely mathematical methods based on convolution. The mathematical description is especially interesting because it promotes fundamental comprehension of angle-resolved scattered light measurement technology and requires significantly less computation time than ray-tracing algorithms. Simplified and idealized assumptions are accepted. To reduce the effort required to simulate the sensor, an attempt was made to implement an idealized mathematical model using Matlab® to be able to quickly generate information on scattered light distribution without excessive effort. Studies were conducted to determine the extent to which the results of modeling correspond to the transfer characteristics of a virtual Zemax sensor, on the one hand, and with the measurement results of the actual scattered light sensor, on the other hand.

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