scholarly journals Methodology for Increasing the Efficiency of Dynamic Process Calculations in Elastic Elements of Complex Engineering Constructions

Electronics ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Andriy Andrukhiv ◽  
Maria Sokil ◽  
Solomiia Fedushko ◽  
Yuriy Syerov ◽  
Yaryna Kalambet ◽  
...  
Keyword(s):  
Dynamic Process ◽  
Granular Media ◽  
Homogeneous Medium ◽  
Dynamic Processes ◽  
Analytical Relationship ◽  
Operational Parameters ◽  
Protective Capacity ◽  
Vibration Displacement ◽  
Complex Engineering ◽  
Elastic Elements

This study deals with a methodology for increasing the efficiency of dynamic process calculations in elastic elements of complex engineering constructions. We studied the complex dynamic processes in a simple engineering construction, a mechanical system of an elastic body–continuous flow of homogeneous medium. The developed methodology is based on the use of a priori information on some of the vibrations forms, the construction of a “simplified” mathematical model of system dynamics, and the obtaining of an analytical relationship that describe the overall range of factors on the elastic vibrations of system. The methodology is used for cases of complex vibrations of elastic bodies, and the obtained results can serve as a basis for choosing the main technological and operational parameters of elastic elements of mechanisms and machines that perform complex vibrations. The results obtained in this work are the basis for calculating the blast effect on the elements of protective structures in order to increase their protective capacity by improving the method of their attachment or by using additional reinforcement, buff load effects on the elements of drilling strings and dynamic processes that occur during surface strengthening by work hardening in order to avoid resonance phenomena, and technological processes of vibration displacement or vibration separation of granular media.

DEM Simulation on the Startup Dynamic Process of a Plain Journal Bearing Lubricated by Granular Media

2014 ◽  
Vol 57 (2) ◽  
pp. 198-205 ◽  
Author(s):  
Wei Wang ◽  
Wei Gu ◽  
Kun Liu ◽  
Fei Wang ◽  
Zhanqi Tang
Keyword(s):  
Dynamic Process ◽  
Granular Media ◽  
Journal Bearing ◽  
Dem Simulation

Terrorism: Group dynamic and interdisciplinary aspects

2021 ◽  
pp. 79-94
Author(s):  
Thomas Wenzel ◽  
Reem Alksiri ◽  
Anthony F. Chen
Keyword(s):  
Human Rights ◽  
Transitional Justice ◽  
Dynamic Process ◽  
The Other ◽  
Dynamic Processes ◽  
Group Dynamic ◽  
Complex Background ◽  
Basic Concepts ◽  
Extreme Violence ◽  
Specific Impact

In this chapter, we offer an interdisciplinary and group-focused model to examine how extreme violence develops, and discuss aspects of interventions for prevention, specifically with regard to terrorism and its many forms. We argue that an analysis of terrorism must be more open, and include research into the perpetrators of extreme violence such as genocide. In general, we see the breakdown of empathy, a group dynamic process that creates the image of ‘the other’ and the violation of basic concepts of humanitarian and human rights laws, as a precondition to terrorism when viewed as a subtype of extreme violence. In recent years, Internet-based and large multinational groups have gained importance, a factor that is insufficiently considered, meaning that more attention is needed on group dynamic processes as drivers of extreme violence. Our interpretation uses models such as that developed by the group analyst Vamik Volkan, and others, including that of chosen trauma. We discuss these factors together with possible strategies to aid transitional justice and contribute to the rehabilitation of victims and perpetrators. The specific impact of each act of terrorism and the needs of victims and society to recover reflect the complex background of each event, and of the contexts in which the crimes were committed.

Emotions and backlash in US society and politics

2020 ◽  
Vol 22 (4) ◽  
pp. 609-618 ◽  
Author(s):  
Roger Petersen
Keyword(s):  
United States ◽  
Dynamic Process ◽  
The United States ◽  
Dynamic Processes ◽  
Complex Emotion ◽  
Political Groups

Alter and Zurn’s framework identifies ‘frequent companions’ to backlash politics including emotive elements. This article addresses those emotive elements. In particular, it defines and unpacks the complex emotion of indignation, an emotion that sets off a dynamic process leading to mutual contempt between political groups. The article shows how indignation and its dynamic processes have helped unleash backlash politics in the United States.

Hierarchical Engineering Model of the Human Body

2016 ◽  
Author(s):  
Somayajulu D. Karamchetty
Keyword(s):  
Human Body ◽  
Hierarchical Modeling ◽  
Control Volume ◽  
The Body ◽  
Whole Body ◽  
Operational Parameters ◽  
Sufficient Detail ◽  
Wide Range ◽  
Level Model ◽  
Complex Engineering

Engineers and scientists are able to understand and analyze the behavior of complex engineering systems in a wide range of critical technologies through hierarchical modeling followed by simulation of the model operation. This process results in a high fidelity integrated model as each level in the hierarchy is modeled in sufficient detail. The overall objective of this effort is to develop a sophisticated hierarchical model of the human body, followed by simulation of the model operation. In this initial research phase, the feasibility of the concept is explored and a framework for the model is described. A six-level model consisting of the whole body as a system, system of systems, organs, tissues, cells, and molecules is proposed and described. This paper explains that the human body is amenable to such hierarchical modeling and describes the benefits that can be achieved. The systems in the body deal with numerous processes: electrical, chemical, biochemical, energy conversion, transportation, pumping, sensing, communications, and so on. Control volume models for the organs in the body capture the mass and energy balance and chemical reactions. Tissue can be represented similar to structural components made of various biomaterials. Cells can be represented as a manufacturing and maintenance workforce assisted by molecular reactions. Following the representation of a healthy body, simulation runs by inserting faults and/or deficiencies in the operational parameters into the model could reveal the causes for specific diseases and illnesses. Such modeling and simulation will benefit medical, pharmaceutical, nutritional specialists, and engineers in designing, developing, and delivering products and services to enable humans to lead healthy lives.

scholarly journals Assortative mating without assortative preference

2015 ◽  
Vol 112 (19) ◽  
pp. 5974-5978 ◽  
Author(s):  
Yu Xie ◽  
Siwei Cheng ◽  
Xiang Zhou
Keyword(s):  
Assortative Mating ◽  
Closed System ◽  
Dynamic Process ◽  
Finite Population ◽  
Social Characteristics ◽  
Dynamic Processes ◽  
Mating Model

Assortative mating—marriage of a man and a woman with similar social characteristics—is a commonly observed phenomenon. In the existing literature in both sociology and economics, this phenomenon has mainly been attributed to individuals’ conscious preferences for assortative mating. In this paper, we show that patterns of assortative mating may arise from another structural source even if individuals do not have assortative preferences or possess complementary attributes: dynamic processes of marriages in a closed system. For a given cohort of youth in a finite population, as the percentage of married persons increases, unmarried persons who newly enter marriage are systematically different from those who married earlier, giving rise to the phenomenon of assortative mating. We use microsimulation methods to illustrate this dynamic process, using first the conventional deterministic Gale–Shapley model, then a probabilistic Gale–Shapley model, and then two versions of the encounter mating model.

Exploring Environments through Water: An Ethno-Hydrography of the Tibesti Mountains (Central Sahara)

2021 ◽  
Vol 12 (1) ◽  
pp. 1-11
Author(s):  
Tilman Musch
Keyword(s):  
Case Studies ◽  
Dynamic Process ◽  
Large Scale ◽  
River System ◽  
Dynamic Processes ◽  
Drainage Basins ◽  
River Systems ◽  
Sandstone Rock ◽  
Central Sahara

An ethno-hydrography, studying the organization of space through water, can provide a key to understanding how people conceive their environments in a holistic way. Based on mapping as a dynamic process, different representations of river systems among the Tubu Teda, who live in the Tibesti mountains (Central Sahara), are described in this paper. I first discuss a large-scale subdivision of the mountains into drainage basins, and then representations of a sub-regional and local river system, including an engraving on a sandstone rock. Finally, I discuss these case studies in the context of holistic experiences of environments and the dynamic processes of mapping.

Projectile oblique impact on granular media: penetration depth and dynamic process

2021 ◽  
Vol 23 (2) ◽  
Author(s):  
Xiaoyan Ye ◽  
Dengming Wang ◽  
Xingyi Zhang ◽  
Chaofeng Zhang ◽  
Wei Du ◽  
...  
Keyword(s):  
Penetration Depth ◽  
Dynamic Process ◽  
Granular Media ◽  
Oblique Impact

scholarly journals Mapping the concentration changes during the dynamic processes of crevice corrosion by digital holographic reconstruction

2009 ◽  
Vol 74 (2) ◽  
pp. 197-202 ◽  
Author(s):  
Henglei Jia ◽  
Shenhao Chen ◽  
Boyu Yuan ◽  
Chao Wang ◽  
Liang Li
Keyword(s):  
Dynamic Process ◽  
Crevice Corrosion ◽  
Three Dimensional ◽  
Solution Concentration ◽  
Dynamic Processes ◽  
Nacl Solution ◽  
Valuable Method ◽  
Concentration Changes ◽  
Holographic Reconstruction

The dynamic process of crevice corrosion during anodic dissolution of a crevice electrode in a 5.0 mmol dm-3 NaCl solution has been studied by digital holographic reconstruction. Digital holographic reconstruction has been proved to be an effective and in situ technique to detect the changes in the solution concentration because useful and direct information can be obtained from the three-dimensional images. It provides a valuable method for a better understanding of the mechanism of crevice corrosion by studying the dynamic processes of changes in the solution concentration at the interface of crevice corrosion.

scholarly journals EXTRACTION OF MINERAL RAW MATERIALS OF A GIVEN SIZE AND DENSITY FROM ROCK MASS BY THE VIBRATION METHOD

2021 ◽  
pp. 27-34
Author(s):  
Vladimir Nadutiy ◽  
Valentina Chеlyshkina ◽  
Vladislav Kurilov
Keyword(s):  
Particle Size ◽  
Rock Mass ◽  
Regression Models ◽  
Granular Media ◽  
Particle Density ◽  
Raw Materials ◽  
Practical Interest ◽  
Conveyor Belt ◽  
Crushed Rock ◽  
Vibration Displacement

Vibration processes are widely used in technology in the processing of bulk materials to improve the efficiency of such operations as transportation, mixing, separation by size and material composition and compaction. Theoretical studies of the processes of vibration displacement of particles in granular media under the influence of vibration are presented by a large number of mathematical models, but many of them need to be compared with experimental data. Practical interest is the determination of the time of ascent of relatively large or densest particles to the surface of a layer of crushed rock mass under the action of the vertical vibration component. The article presents the results of an experimental study of this process. A set of experiments on the extraction of basalt particles from tuff rock mass (waste from basalt quarries), ferruginous quartzites from the mass of dump rock, and relatively large granite particles from crushed granite mass was performed. Processing of the experiments using the SPSS Statistics program allowed us to analyze the process and obtain regression models for determining the time of ascent of a particle of a given size and density from the rock mass, including two generalized regression models. In the first of them, the variables were the amplitude and frequency of vibration, the particle size of the medium was 25 mm, the particle density of the medium was 1.6-2.8 g/cm3, the particles floating under the action of vibration have a particle size of 50 mm, their density varies from 2.5 to 5.1 g/cm3. In the second model for А= 5 мм, w=30 Гц, an additional variable factor is the size of the floating particle, which varies from 50 to 25 mm The resulting equations allow us to determine the time of ascent and predict the extraction of particles of a given size and density under the influence of vibration, for example on the conveyor belt, without conducting cumbersome experiments.

scholarly journals The Problem of Dynamic Process Manifestation in Identification of Organic Compounds by NMR Spectroscopy

2020 ◽  
Vol 10 (1) ◽  
pp. 63-76
Author(s):  
N. E. Kuz’mina ◽  
S. V. Moiseev ◽  
A. I Luttseva
Keyword(s):  
Nmr Spectroscopy ◽  
Organic Compounds ◽  
Dynamic Process ◽  
Amide Bond ◽  
Dynamic Processes ◽  
Chemical Calculation ◽  
Negative Effects ◽  
Pharmaceutical Substances ◽  
Nonvalent Interactions ◽  
Intramolecular Dynamic

The number, shape and position of NMR spectral lines depend on dynamic processes, and this creates certain difficulties in identification of pharmaceutical substances by NMR spectroscopy. The aim of the paper was to study instances of manifestation of intramolecular dynamic processes that affect identification of organic compounds by NMR, and to illustrate the potential of the methods used for their reduction, as well as associated problems.Materials and methods: 1H and 13C spectra of the following pharmaceutical substances: «buserelin acetate», «valsartan», «goserelin acetate», «iopromide», «clopidogrel hydrogensulfate», «omeprazole», «proroxan», «risperidone», «triptorelin acetate», and «enalapril maleate» were used to demonstrate negative effects of dynamic processes. The spatial structures of conformers were established by 1H-1H ROESY experiments. The quantum-chemical calculation of geometric and thermodynamic characteristics of different conformers was carried out by the PM3 method, and electronic characteristics—by the AM1 method with the help of the HyperChem software.Results: the authors analysed intramolecular dynamic processes which are most commonly encountered in expert work: pyramidal inversion of nitrogen in a heterocyclic compound (risperidone, proroxan, clopidogrel), rotation of molecular fragments around the amide bond (valsartan, iopromide, enalapril), prototropic rearrangements (buserelin, goserelin, omeprazole, triptorelin). The change in exchange rates was explained from the perspective of the change in the system of intra- and intermolecular nonvalent interactions.Conclusions: the use of traditional methods for increasing the rate of dynamic processes (increasing the temperature and changing the solvent) does not always eliminate the negative effects of intramolecular transformations. Methods of smoothing the spectral manifestations of dynamic processes have limited application due to strong intramolecular nonvalent interactions which prevent the conversion of the dynamic process rate into fast exchange. Experts and manufacturers should take into account the manifestation of dynamic processes during identification of pharmaceutical substances by NMR spectroscopy.

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