Improving the accuracy of virtual simulation and ensuring vibration reliability of on-board electronic equipment
The article discusses current issues related to the development and application of virtual simulation to ensure the reliability of the electronic equipment in the presence of vibrations on the on-board equipment of the object of its installation. The authors constructed an algorithm of the method of ensuring vibration reliability of developed structures of electronic equipment in the process of virtual simulation with receiving the vibration fields on the structures and mechanical loads on each electronic component.
By analyzing the logs of corporate e-mail networks we found a number of patterns, showing how the size of ego-networks of individual employees changes on a day by day basis. We proposed a simple model that adequately describes the observed time dependence of an employee's "social circle". Comparison of experimental data with the theoretical model showed that employees are divided into two groups - with fast and slow changes in their social circles, respectively. We believe that the presence of these groups reflects both project-type and process-type of employees' activities. Comparison of data obtained before and during the global economic crisis has shown that the crisis led to an actual reduction in project-type activities.
The considered model of the failure rate of CMOS VHSIC design proposed in the article Piskun G.A., Alekseev V.F., "Improvement of mathematical models calculating of CMOS VLSIC taking into account features of impact of electrostatic discharge", published in the first issue of the journal "Technologies of electromagnetic compatibility" for the year 2016. It is shown that the authors claim that this model "...will more accurately assess the reliability of CMOS VHSIC design" is fundamentally flawed and its application will inevitably lead to inadequate results. Alternatively, the proposed model of the failure rate of CMOS VHSIC design, which also allows to take into account the views of ESD, but based on the use of resistance characteristics of CMOS VHSIC to the effects of ESD.
This paper describes the experience of the application of the design approach which is used in the HSE - Nizhny Novgorod in the teaching of accounting (financial) accounting, auditing, economic analysis. The stages of a complex project, as benefits of this approach and the problems that arise.
New trends, technologies and symbols of the "Design and advertisement 2013" exhibition with illustrated examples are described in the article.
The methodology and software tools for multi-level thermal and electro-thermal design of electronic components is presented. The discussion covers 2D/3D constructions of: 1) discrete and integrated semiconductor devices; 2) monolithic and hybrid ICs; 3) MCMs and PCBs. The actual test validation through thermal measurement is demonstrated for all types of components.
Brazil and Germany have a "shared history" or shared stories that refer not only to the similarities and differences between the two countries, but also to cultural approaches between them despite the socio-cultural differences and geographical distance. Accordingly, the contributions in this volume highlight the German Brazilian relations in design, film, literature, and media. At the same time they discuss motivations, connections, comparisons and inspirations of these relations.
The volume contains articles of scientific staff and faculty of the Department of Computer Science and Applied Mathematics and Scientific-Educational Center of computer modeling of unique buildings and complexes of Moscow State University of Civil Engineering (National Research University), devoted to actual problems of applied mathematics and computational mechanics.
The results concern roll pass design for rolling a round bar of a 20mm diameter from a 55mm diameter input. Concerning materials, this roll pass design must cover a wide range of steels, from low-carbon micro-alloyed steels to stainless steels. The roll pass design proposal takes into consideration lower plasticity of certain steels. The comparison was enabled by suggesting two roll pass designs. The classical oval-round roll pass design, where the maximum extension coefficient is set to 1.55 in oval and 1.22 in round grooves. The second roll pass design uses a combination of smooth part of the roll (curves) and round roll passes. Distribution of the extension coefficient in individual passes is similar to that of oval-round series. The paper also compares values of energy-force parameters calculated analytically using the method of finite elements. If we compare the distribution of temperature, stress and size of the grain, it is proved that the oval-round roll pass designs are the best as far as the balanced distribution of the above-mentioned values is concerned. The roll pas design combining smooth part of the roll with a round part does not achieve such balance. However, its advantage lies in far lower requirement for the needed length of the working part of the roll. Five passes are carried out on the smooth part of the roll, which considerably cuts down the required length of the roll body. Therefore it is this variant that will be used in the laboratory of wire rolling created within the project RMSTC.