734 research outputs found
The shock-acoustic waves generated by earthquakes
We investigate the form and dynamics of shock-acoustic waves generated by
earthquakes. We use the method for detecting and locating the sources of
ionospheric impulsive disturbances, based on using data from a global network
of receivers of the GPS navigation system and requiring no a priori information
about the place and time of associated effects. The practical implementation of
the method is illustrated by a case study of earthquake effects in Turkey
(August 17, and November 12, 1999), in Southern Sumatera (June 4, 2000), and
off the coast of Central America (January 13, 2001). It was found that in all
instances the time period of the ionospheric response is 180-390 s, and the
amplitude exceeds by a factor of two as a minimum the standard deviation of
background fluctuations in total electron content in this range of periods
under quiet and moderate geomagnetic conditions. The elevation of the wave
vector varies through a range of 20-44 degree, and the phase velocity
(1100-1300 m/s) approaches the sound velocity at the heights of the ionospheric
F-region maximum. The calculated (by neglecting refraction corrections)
location of the source roughly corresponds to the earthquake epicenter. Our
data are consistent with the present views that shock-acoustic waves are caused
by a piston-like movement of the Earth surface in the zone of an earthquake
epicenter.Comment: EmTeX-386, 30 pages, 4 figures, 3 tabl
The flows structure in unsteady gas flow in pipes with different cross-sections
The results of numerical simulation and experimental study of the structure of unsteady flows in pipes with different cross sections are presented in the article. It is shown that the unsteady gas flow in a circular pipe is axisymmetric without secondary currents. Steady vortex structures (secondary flows) are observed in pipes with cross sections in the form of a square and an equilateral triangle. It was found that these secondary flows have a significant impact on gas flows in pipes of complex configuration. On the basis of experimental researches it is established that the strong oscillatory phenomena exist in the inlet pipe of the piston engine arising after the closing of the intake valve. The placement of the profiled plots (with a cross section of a square or an equilateral triangle) in the intake pipe leads to the damping of the oscillatory phenomena and a more rapid stabilization of pulsating flow. This is due to the stabilizing effect of the vortex structures formed in the corners of this configuration. © The authors, published by EDP Sciences, 2017.Thus, in this study it was found that the cross-sectional shape of the pipe has a significant impact on the structure of the gas flow. The secondary flows (steady vortex structures) are formed in pipes with cross sections in the form of a square and an equilateral triangle. Secondary flows (steady vortex structures) in the pipe can stabilize the pulsing flows. This phenomenon can be used in the design of the intake and exhaust systems of energy machines and plants with a view to their gas-dynamic improvement. The work has been supported by the Russian Science Foundation (grant No. 17 -69-00002)
COMPARATIVE ANALYSIS OF TOOLS FOR ESTIMATION OF INVESTMENT CLIMATE OF TERRITORIES
Purpose: The present paper is a study of the most well-known foreign and domestic methods for assessing the investment climate of the regions as well as identifying their main disadvantages.
Methodology: The study of regional investment issues should be based on a systematic approach taking into account the positive and negative aspects of each methodology separately.
Result: Opportunities to improve the competitiveness of the constituent entities of the Russian Federation are considered, too. The existing methods applied by various research-rating agencies are considered in detail.
Applications: This research can be used for the universities, teachers and education students.
Novelty/Originality: In this research, the model of comparative analysis of tools for estimation of the investment climate of territories is presented in a comprehensive and complete manner
Simulation of stationary gas flows in the intake pipe of piston engine in the AVL FIRE software
В статье представлены результаты математического моделирования стационарных газовых потоков во впускном трубопроводе поршневого двигателя внутреннего сгорания. Математическое моделирование выполнялось с помощью программного обеспечения AVL FIRE, разработанного австрийской фирмой AVL Ltd. В статье представлены результаты моделирования в виде распределения векторов скорости во впускном канале и клапанной щели, а также их анализ. Производится сравнение полученных результатов с результатами других авторов. Установлено, что разработанная модель корректно описывает процессы, происходящие при течении газовых потоков в каналах поршневых двигателей, и она может быть использована для дальнейших исследований.The results of mathematical modeling of stationary gas flows in the intake pipe of an internal combustion engine are presented in the article. Mathematical modeling was performed using the AVL FIRE software, developed by the AVL Ltd Austrian firm. Distribution of velocity vectors in the intake pipe and the valve gap and their analysis are presented in this paper as the simulation results. The comparison of the obtained results with results of other authors is made in the article. The developed model describes correctly the processes occurring during the flow of gas streams in the pipes of piston engines, and it can be used for further research
Brattleboro rats as the model of blood hyperviscosity syndrome for testing substances with hemorheological activity
Educational programs improvement directions of different levels in high school
The paper presents the results of research on the possibilities to improve the educational process at the university and the basic conditions of their realization. The authors developed the model of the next generation education program (EP) based on the analysis of the experience of "International Society for Engineering Pedagogy" and the CDIO. The paper presents data poll of young and experienced lecturers on need and importance of the next generation EP, as well as the readiness of their education departments and teachers to implement the next generation EP requirements in training bachelors and masters. Qualification characteristics of university lecturers, capable of solving problems of the next generation EP development and effective implementation; requirements for methodological tools for educational process monitoring; needs to raise the educational culture in order to form valuable attitude and responsibility of both lecturers and students for the results of their joint work are defined in the paper on the basis of empirical data. Generalization of results of the research allowed formulation of a number of actual tasks for education departments since their decision influences the quality of the ultimate results realized in the educational process. © Published under licence by IOP Publishing Ltd.Russian Science Foundation, RSF: 18-79-10003The work has been supported by the Russian Science Foundation (grant No. 18-79-10003)
Technology for Training Creative Graduates in Engineering Bachelor’s Programs
This article is devoted to technologies of engineering education that produce the most in-demand professional qualities of graduates from Bachelor’s programs. A review of studies about introducing innovations to improve the educational process in practice-oriented Bachelor’s studies is carried out. The advantages and limitations of project-based and problem-based learning technologies are defined. The work presents the experience of developing and applying a unique teaching technology based on the integration of problemand project-based training approaches, designed to enhance the creativity of the study process in engineering Bachelor’s programs. It is described with a focus on the mechanisms for the integrated use of the advantages of methods of problemand project-based training in the formation of the professional competencies required for an engineer’s innovative activity in the development of a new product project. The data from an empirical study have been considered; they allow us to substantiate the conclusion that the integration of projectand problem-based learning in the form of a holistic technology is effective for developing students’ creative capacities
Adaptation or Degradation: What’s Happen to Educational Innovation in a Typical Educational Process?
The article is devoted to the study of the processes of changing innovative learning technology in the conditions of a typical educational process. The study was conducted on the example of end-to-end design technology (based on the CDIO methodology in accordance with its standards) for bachelor’s degree in technical areas of training. The study used methods of expert assessment, written survey, content analysis, structural-logical and statistical analysis. The experts were engineers of design departments of industrial enterprises, teachers of engineering disciplines of the university and undergraduate students. A review analysis of the understanding of educational innovation available in the scientific literature is carried out. A concise description of the end-to-end design technology for a training and production workshop that meets the criteria of educational innovation is presented. Based on the expert assessment, a detailed analysis of the influence of the conditions of the typical educational process of the university on the change of the specified learning technology at the level of the characteristics of students’ academic work and its results is made. Data on changes in innovative technology according to the criteria of twelve CDIO standards, as well as its impact on the formation of hard and soft skills of engineers before and after adaptation are presented. A comparative analysis of the assessments of changes in teaching technology made by students and experts is carried out, on the basis of which conclusions are substantiated about: 1) the nature of the degradation of educational innovation when it is introduced into the standard learning process; 2) the special role of the first stages of end-to-end design technology for the formation of effective skills of educational and practical work, which partially compensate for the shortcomings of the educational process caused by its adaptation to the conditions of a typical university education. A hypothesis is also put forward about the reasons for the low efficiency of educational innovations in the educational process of universities
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