Математическое моделирование социальных процессов
Free bulging process is an experimental technique which can be used to characterize a sheet material in conditions of biaxial tension during hot forming. Analytical and semi-analytical models of this process are usually based on the hypothesis offering certain relations between the geometrical characteristics of a bulge during forming. The paper presents an original relation between a specimen thickness at the dome pole and the dome height which is used at the semi-analytical method for simulation of free bulging process. In order to obtain this relation, the finite-element computer simulation results were generalized. The influence of the material constants on the geometrical parameters of the bulge was studied. It was shown that the sheet thickness corresponding to a specific dome height is dictated by the strain rate sensitivity index of the material. The equation describing the influence of the strain rate sensitivity index on the dome apex thickness is presented.
Currently, the tasks of ensuring the quality and stability of the provided IT services are extremely topical. In the operation of the composite applications, the problem of increasing the effectiveness of incident management is a complex technical problem, the solution of which requires the use of the simulation methods. In the work, the integration platform Ensemble of InterSystems Company was considered as a basis for designing integration solutions. Given the architectural features of the integration platforms, a mathematical model of the incident management process in the Ensemble integration platform is proposed. This mathematical model was used to develop algorithms for identifying and classifying incidents. The results of the work can be used in the design and development of incident management information systems, as well as in organizing the work of technical support services for IT companies
We consider the problem of manipulability of social choice rules in the impartial anonymous and neutral culture model (IANC) and provide a new theoretical study of the IANC model, which allows us to analytically derive the difference between the Nitzan-Kelly index in the Impartial Culture (IC) and IANC models. We show in which cases this difference is almost zero, and in which the Nitzan-Kelly index for IANC is the same as for IC. However, in some cases this difference is large enough to cause changes in the relative manipulability of social choice rules. We provide an example of such cases.
The paper is oriented toward the problem of determination of rheological characteristics of a material by free bulging testing. This information about the material behavior is used for design of gas forming technologies for production of complex shell parts used in aerospace industry. Realization of such technologies requires pressure forming regimes which can be calculated using computer simulation. The material model describing its behavior during hot forming is one of the most important inputs of the simulation. Tensile testing is the most popular way of investigation of the material behavior. A significant disadvantage of this method is that the material formed in conditions of uniaxial tension which is not similar to the one realized in gas forming technologies. Free bulging technique considered in the paper allows one to study the behavior of a material during hat forming in condition of biaxial tension. Inverse analysis utilizing a special semianalytical model for the direct task is used for interpretation of the results. The model is based on the differential equation describing the evolution of dome height using special relation for the calculation of specimen thickness at the dome pole. This approach was applied for the processing of experimental results obtained by forming of industrial aluminum alloys. The obtained material constants were also used in finite element simulation of bulging process by MSC.Nastran software in order to verify the efficiency of proposed technique. The results of the simulations were found to be in good agreement with the experimental data.
This study seeks to analyze how students apply a mathematical modeling skill that was previously learned by solving standard word problems to the solution of word problems with nonstandard contexts. During the course of an experiment involving 106 freshmen, we assessed how well they were able to transfer the mathematical modeling skill that is used to solve standard problems to the solution of nonstandard ones that had an analogous structure. The results of our research show that students had varying degrees of success applying the different stages of modeling depending on whether they were solving a familiar problem (involving near transfer) or one that had an unfamiliar context (involving far transfer): in cases of near transfer, students applied the template formally even though it did not align with the text of the new word problem, which complicated further interpretation. In cases of far transfer, students chose to solve the problem by using an ordinary method of selecting a solution by trial and error in preference to the use of modeling. Thus, the application of the modeling skill as a multistage process is complicated when solving nonstandard problems involving either near or far transfer.
This book deals with mathematical problems arising in the context of meteorological modelling. It gathers and presents some of the most interesting and important issues from the interaction of mathematics and meteorology. It is unique in that it features contributions on topics like data assimilation, ensemble prediction, numerical methods, and transport modelling, from both mathematical and meteorological perspectives.
The derivation and solution of all kinds of numerical prediction models require the application of results from various mathematical fields. The present volume is divided into three parts, moving from mathematical and numerical problems through air quality modelling, to advanced applications in data assimilation and probabilistic forecasting.
The book arose from the workshop “Mathematical Problems in Meteorological Modelling” held in Budapest in May 2014 and organized by the ECMI Special Interest Group on Numerical Weather Prediction. Its main objective is to highlight the beauty of the development fields discussed, to demonstrate their mathematical complexity and, more importantly, to encourage mathematicians to contribute to the further success of such practical applications as weather forecasting and climate change projections. Written by leading experts in the field, the book provides an attractive and diverse introduction to areas in which mathematicians and modellers from the meteorological community can cooperate and help each other solve the problems that operational weather centres face, now and in the near future.
Readers engaged in meteorological research will become more familiar with the corresponding mathematical background, while mathematicians working in numerical analysis, partial differential equations, or stochastic analysis will be introduced to further application fields of their research area, and will find stimulation and motivation for their future research work.
This article is talking about state management and cultural policy, their nature and content in term of the new tendency - development of postindustrial society. It mentioned here, that at the moment cultural policy is the base of regional political activity and that regions can get strong competitive advantage if they are able to implement cultural policy successfully. All these trends can produce elements of new economic development.