scholarly journals Stabilization of the response of cyclically loaded lattice spring models with plasticity

2020 ◽  
Author(s):  
Ivan Gudoshnikov ◽  
Oleg Makarenkov
Keyword(s):  
Geometric Condition ◽  
Periodic Regime ◽  
Initial Condition ◽  
Quasistatic Evolution ◽  
Dimensional Network ◽  
Elastic And Plastic Deformations ◽  
Sweeping Processes ◽  
Normal Vectors ◽  
The One ◽  
The Given

This paper develops an analytic framework to design both stress-controlled and displacement-controlled T -periodic loadings which make the quasistatic evolution of a one-dimensional network of elastoplastic springs converging to a unique periodic regime. The solution of such an evolution problem is a function t->(e(t),p(t)), where ei(t) and pi(t) are the elastic and plastic deformations of spring i, that satisfies the initial condition (e(t0),p(t0)). After we rigorously convert the problem into a Moreau sweeping process with a moving polyhedron C(t) in a vector space E of dimension d, it becomes natural to expect (based on a result by Krejci) that the elastic component t->e(t) always converges to a T-periodic function. The achievement of the present paper is in spotting a class of loadings where the Krejci's limit doesn't depend on the initial condition (e(t0),p(t0)) and so all the trajectories approach the same T-periodic regime. The proposed class of sweeping processes is the one for which the normal vectors of any d different facets of the moving polyhedron C(t) are linearly independent. We further link this geometric condition to mechanical properties of the given network of springs. In this way we obtain an analogue of the Frederick-Armstrong theorem from continuum mechanics.

THE EU SUGAR MARKET PROFILE AND ITS MAIN DRIVERS

2015 ◽  
Author(s):  
Lubos SMUTKA ◽  
Irena BENEŠOVÁ ◽  
Patrik ROVNÝ ◽  
Renata MATYSIK-PEJAS
Keyword(s):  
Market Failure ◽  
Current System ◽  
Quota System ◽  
Considerable Debate ◽  
Sugar Market ◽  
The Common ◽  
The One ◽  
Production Capacities ◽  
The Given ◽  
The Eu

Sugar is one of the most important elements in human nutrition. The Common Market Organisation for sugar has been a subject of considerable debate since its establishment in 1968. The European agricultural market has been criticized for its heavy regulations and subsidization. The sugar market is one of the most regulated ones; however, this will change radically in 2017 when the current system of production quotas will end. The current EU sugar market changed is structure during the last several decades. The significant number of companies left the market and EU internal sugar market became more concentrated. The aim of this paper is presentation characteristics of sugar market with respect to the supposed market failure – reduction in competition. The analysis also identifies the main drivers and determinants of the EU especially quota sugar market. In relation to paper’s aim the following results are important. The present conditions of the European sugar market have led to market failure when nearly 75 % (10 million tonnes) of the quota is controlled by five multinational companies only. These multinational alliances (especially German and French one) are also taking control over the production capacities of their subsidiaries. In most countries, this causes serious problems as the given quota is controlled by one or two producers only. This is a significant indicator of market imperfection. The quota system cannot overcome the problem of production quotas on the one hand and the demand on the other; furthermore, it also leads to economic inefficiency. The current EU sugar market is under the control of only Sudzucker, Nordzucker, Pfeifer and Langen, Tereos and ABF.

Quasi-Periodic Control Technique for Minimizing Fuel Consumption During Record Vehicle Competition

2013 ◽  
Vol 60 (2) ◽  
pp. 185-197 ◽  
Author(s):  
Paweł Sulikowski ◽  
Ryszard Maronski
Keyword(s):  
Fuel Consumption ◽  
Optimal Control Theory ◽  
Slope Angle ◽  
Control Technique ◽  
Decision Variables ◽  
Aeronautical Engineering ◽  
The One ◽  
Optimal Driving ◽  
The Given ◽  
Engine Power

The problem of the optimal driving technique during the fuel economy competition is reconsidered. The vehicle is regarded as a particle moving on a trace with a variable slope angle. The fuel consumption is minimized as the vehicle covers the given distance in a given time. It is assumed that the run consists of two recurrent phases: acceleration with a full available engine power and coasting down with the engine turned off. The most fuel-efficient technique for shifting gears during acceleration is found. The decision variables are: the vehicle velocities at which the gears should be shifted, on the one hand, and the vehicle velocities when the engine should be turned on and off, on the other hand. For the data of students’ vehicle representing the Faculty of Power and Aeronautical Engineering it has been found that such driving strategy is more effective in comparison with a constant speed strategy with the engine partly throttled, as well as a strategy resulting from optimal control theory when the engine is still active.

Differences in the Blood-Supply of Bone of Different Histological Types

1960 ◽  
Vol s3-101 (55) ◽  
pp. 351-370
Author(s):  
J. D. CURREY
Keyword(s):  
Blood Supply ◽  
Unit Volume ◽  
Waste Products ◽  
Cement Line ◽  
Marrow Cavity ◽  
Woven Bone ◽  
Dimensional Network ◽  
Periosteal Surface ◽  
Similar Distance ◽  
The One

‘Laminar’ bone, commonly found in artiodactyls and dinosaurs, is described. It consists of a series of bony laminae arranged like tree-rings round the marrow cavity, each lamina being between 0.1 and 0.2 mm thick. Sandwiched between each lamina and the next is an effectively two-dimensional network of blood-vessels. Laminar bone grows in a series of spurts; a sheet of woven-fibred bone is formed very quickly, not actually on the pre-existing sub-periosteal surface, but separated from it by a space. The new bone is held clear of the original surface by an occasional bridge of bone. The space so formed is filled in slowly by parallel-fibred lamellar bone, and while this is going on more woven bone, with spaces, may be formed by the periosteum. The vascularization of laminar bone on the one hand and bone composed of haversian systems on the other is compared, chiefly in cattle. Laminar bone has a more intimate blood-supply than haversian bone, and it has a larger surface area of bloodchannel per unit volume. The volume of channel per unit volume is about equal in the two types of bone. The mean distance between anastomoses is less in laminar than in haversian bone. The cement-line round haversian systems hinders the passage of materials through the canaliculi. The osteocytes in the interstitial lamellae are thus in a worse position for obtaining foodstuffs and disposing of waste products than osteocytes in laminar bone a similar distance from the nearest blood-vessel. It is suggested that the formation of haversian systems in laminar bone interferes with the latter's blood-supply and leads to the formation of further haversian systems.

"THE SYNTHESIS OF WAR AND THEATRE": SOCIO-HUMANITARIAN DISCOURSE ON THE ESSENCE OF TERRORISM

2020 ◽  
pp. 10-23
Author(s):  
Irina V Malygina ◽  
◽  
Anna V Malygina ◽  
Keyword(s):  
International Terrorism ◽  
Complex Nature ◽  
Cultural Resources ◽  
Self Presentation ◽  
The Status ◽  
World Cultural Heritage ◽  
The One ◽  
Strategic Object ◽  
The Given

The article reveals the heuristic potential of social and humanitarian knowledge in understanding the complex nature of terrorism. The given research optics allows to expand traditional frameworks of considering terrorism as a phenomenon caused by political, ideological and economic factors; to reveal and substantiate deep cultural and mental reasons of the given phenomenon; make sense of terrorism as a destructive form of cultural identity. The cultural and historical origins of modern terrorism, which is closely connected with radical Islam, are analyzed in the civilizational system of coordinates “West–East”. The system of argumentation is based on scientific concepts and current artistic practices that interpret the causes of inter-civilizational tension resulting in international terrorism. The change of the status of the artist in the “epoch of terrorism” is analyzed; the theme of theatricalization and aestheticization of terrorist actions and the role of media in these processes are problematized. As a newest trend, which has not received any serious theoretical reflection, the text considers the phenomenon conditionally designated as “sublimation of terrorist activity into a symbolic sphere”, which is manifested in the destruction of monuments of world cultural heritage, in the orientation to culture as a new strategic object of terrorist attacks, on the one hand, and the use of cultural resources for self-presentation and promotion of their ideology by terrorist organizations, on the other

Influence of Food and Larval Age on the Defensive Chemistry of Satumia pyri

2001 ◽  
Vol 56 (1-2) ◽  
pp. 89-94 ◽  
Author(s):  
Reinhold Deml
Keyword(s):  
Body Fluids ◽  
The Other ◽  
Larval Diet ◽  
Larval Instars ◽  
Defensive Chemistry ◽  
Crataegus Monogyna ◽  
Secondary Compound ◽  
Influence Of Food ◽  
The One ◽  
The Given

Abstract Scolus secretions and hemolymph of caterpillars of Satumia pyri fed with two different foodplants (Crataegus monogyna, Prunus spinosa) were chemically analyzed and their chemical similarities determined. The secondary-compound patterns obtained for the two body fluids showed no significant differences when compared between the two groups of alterna­ tively fed last-instar larvae. Thus, the composition of these fluids of full-grown caterpillars is not influenced by the larval diet. However, younger larvae on P. spinosa revealed a diversity of compounds differing significantly from that of larger caterpillars fed with either C. mono­gyna (both body fluids) or P. spinosa (hemolymph only). This indicates that, on the one hand, the hemolymph composition is adapted to the changing physiological requirements of the given instars whereas, on the other hand, the defensive mixtures remain unaltered in the late larval instars due to a constant spectrum of potential enemies.

Multidimensional regular C-fraction with independent variables corresponding to formal multiple power series

2019 ◽  
Vol 150 (4) ◽  
pp. 1853-1870 ◽  
Author(s):  
R. I. Dmytryshyn
Keyword(s):  
Power Series ◽  
Continued Fractions ◽  
Numerical Experiments ◽  
The Other ◽  
Independent Variables ◽  
Classical Algorithm ◽  
Multiple Power ◽  
The One ◽  
The Given ◽  
Multiple Power Series

AbstractIn the paper the correspondence between a formal multiple power series and a special type of branched continued fractions, the so-called ‘multidimensional regular C-fractions with independent variables’ is analysed providing with an algorithm based upon the classical algorithm and that enables us to compute from the coefficients of the given formal multiple power series, the coefficients of the corresponding multidimensional regular C-fraction with independent variables. A few numerical experiments show, on the one hand, the efficiency of the proposed algorithm and, on the other, the power and feasibility of the method in order to numerically approximate certain multivariable functions from their formal multiple power series.

scholarly journals Integrative concept of homeostasis: translating physiology into medicine

F1000Research ◽  
2014 ◽  
Vol 3 ◽  
pp. 299
Author(s):  
Ivan Spasojević
Keyword(s):  
Living System ◽  
Living Systems ◽  
Initial Condition ◽  
Adult Human ◽  
Input Side ◽  
Tremendous Amount ◽  
To Come ◽  
Integrative Concept ◽  
The One ◽  
Reductionist Approach

To truly understand living systems they must be viewed as a whole. In order to achieve this and to come to some law that living systems comply with, the reductionist approach, which has delivered a tremendous amount of data so far, should be complemented with integrative concepts. The current paper represents my humble attempt towards an integrative concept of homeostasis that would describe the (patho)physiological setup of adult human/mammal system, and that might be applicable in medicine. Homeostasis can be defined as time- and initial-condition-independent globally stabile state of non-equilibrium of a living system in which the interactions of system with the surroundings and internal processes are overall in balance or very near it. The presence of homeostasis or the shift from homeostasis of an adult human/mammal system can be described by equation that takes into account energy and informational input and output, catabolism and anabolism, oxidation and reduction, and entropy, where changes in the input should equal changes in the output within a specific period of time. Catabolism and oxidation are presented on the input side since the drive of the surroundings is to decompose and oxidize living systems, i.e. systems are under constant 'catabolic and oxidative pressure'. According to the equation, homeostasis might be regained by changing any of the input or output components in a proper manner (and within certain limits), not only the one(s) that has/have been changed in the first place resulting in the deviation from homeostasis.

scholarly journals Сlassical solution of the mixed problem for the one-dimensional wave equation with the nonsmooth second initial condition

2020 ◽  
Vol 64 (6) ◽  
pp. 657-662
Author(s):  
V. I. Korzyuk ◽  
J. V. Rudzko
Keyword(s):  
Boundary Condition ◽  
Wave Equation ◽  
Mixed Problem ◽  
Method Of Characteristics ◽  
Smooth Boundary ◽  
Analytical Form ◽  
Initial Condition ◽  
One Dimensional ◽  
The One ◽  
Dimensional Wave

In this article, we study the classical solution of the mixed problem in a quarter of a plane and a half-plane for a one-dimensional wave equation. On the bottom of the boundary, Cauchy conditions are specified, and the second of them has a discontinuity of the first kind at one point. Smooth boundary condition is set at the side boundary. The solution is built using the method of characteristics in an explicit analytical form. Uniqueness is proved and conditions are established under which a piecewise-smooth solution exists. The problem with linking conditions is considered.

scholarly journals REAL PRODUCT SIZE ACCOUNTING PROBLEM AT WAVE DEFORMATION HARDENING

2020 ◽  
Vol 2020 (1) ◽  
pp. 4-10
Author(s):  
Andrey Kirichek ◽  
Sergey Barinov ◽  
Aleksandr Yashin ◽  
Aleksey Zaycev ◽  
Aleksandr Konstantinov
Keyword(s):  
Deformation Pattern ◽  
Product Size ◽  
Wave Deformation ◽  
Processing Modes ◽  
Deformation Hardening ◽  
Different Shapes ◽  
The One ◽  
The Impact ◽  
The Given ◽  
Geometrical Dimensions

The article raises the problem of the need to take into account real dimensions when they are strengthened by wave deformation. The fact is that in carrying out initial calculations the overall dimensions of the models under study are quite often neglected. On the one hand, this makes it possible to significantly simplify the calculation of the flat model, and on the other - to exclude consideration of the influence of geometric dimensions of the sample on the process to be followed. This is especially relevant in the study of shock systems in which wave processes lie. The effect of the final samples on the hardening process should not be excluded. This is because the elastic-stic deformation pattern has its own features. Hardening is carried out due to transmission of energy in the form of deformation wave, which is transformed on all gras with variable acoustic rigidity, including on boundaries, which are final dimensions of the analysed sample. Preliminary studies have developed a significant effect on the process of wave deformation hardening of geometrical dimensions of the material to be treated, since at equal volumes of strengthened materials and processing modes different distribution of microassay in the surface layer is observed. The established algorithm of further research of the given direction will allow not only to reveal the regularities of through strengthening of samples of different shapes and sizes, but also to establish the possibility of contactless de-formation strengthening of the sides of the sample opposite to the impact of the HRD, which have a complex profile shape, as well as the possibility of contactless deformation strengthening of internal hard-to-reach surfaces.

Dimensionality and Construct Validity of a Video-Based, Objective Personality Test for the Assessment of Willingness to Take Risks in Road Traffic

2005 ◽  
Vol 97 (1) ◽  
pp. 309-320 ◽  
Author(s):  
Martin E. Arendasy ◽  
Andreas Hergovich ◽  
Markus Sommer ◽  
Bettina Bognar
Keyword(s):  
Construct Validity ◽  
Personality Trait ◽  
Road Traffic ◽  
Personality Test ◽  
Traffic Situation ◽  
One Dimensional ◽  
First Results ◽  
The One ◽  
The Given ◽  
Homeostasis Theory

The study at hand reports first results about the dimensionality and construct validity of a newly developed objective, video-based personality test, which assesses the willingness to take risks in traffic situations. On the basis of the theory of risk homeostasis developed by Wilde, different traffic situations with varying amounts of objective danger were filmed. These situations mainly consisted of situations with passing maneuvers and speed choice or traffic situations at intersections. Each of these traffic situations describes an action which should be carried out. The videos of the traffic situations are presented twice. Before the first presentation, a short written explanation of the preceding traffic situation and a situation-contingent reaction is provided. The respondents are allowed to obtain an overview of the given situations during the first presentation of each traffic situation. During the second presentation the respondents are asked to indicate at which point the action that is contingent on the described situation will become too dangerous to carry out. Latencies for items were recorded as a measure for the magnitude of the person's subjectively accepted willingness to take risks in the sense of the risk homeostasis theory by Wilde. In a study with 243 people with different education and sex, the one-dimensionality of the test corresponding to the latency model by Scheiblechner was investigated. Analysis indicated that the new measure assesses a one-dimensional latent personality trait which can be interpreted as subjectively accepted amount of risk (target risk value). First indicators for the construct validity of the test are given by a significant correlation with the construct-related secondary scale, adventurousness of the Eysenck Personality Profiler with, at the same time, nonsignificant correlations to the two secondary scales, extroversion and emotional stability, that are not linked to the construct.

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