scholarly journals Choice substantiation of a folded foundation model via laboratory experiment

2019 ◽  
Vol 1 (52) ◽  
pp. 139-145
Author(s):  
Radomir Timchenko ◽  
Dmytro Krishko ◽  
Iryna Khoruzhenko
Keyword(s):  
Experimental Studies ◽  
Experiment Planning ◽  
Foundation Design ◽  
Basic Principles ◽  
Scientific Experiment ◽  
Thin Walled Structures ◽  
Foundation Model ◽  
Recent Developments ◽  
Thin Walled ◽  
Shell Foundations

The examples of recent developments of foundation thin-walled structures and their applications are presented. It is notedthat the purpose is to develop a method for conducting experimental studies of contact interaction between a folded shellfoundation and a deformed base. The purpose of the laboratory tray research is to determine the optimal characteristics of thesuggested foundation design. The article suggested a method for conducting a laboratory tray experiment to compare the operationof two models of folded shell foundations. The main stages of conducting the scientific experiment have been describedand the basic principles of selecting materials, devices and equipment for carrying out the experiment have been considered.The conduct of the experiment including data recording for each foundation model has been described. As a result,subsidence data for each foundation model have been obtained. The findings have been analyzed; subsidence graphs for eachfoundation design have been built. It is concluded that better distribution of external load to the foundation system elementsis achieved due to the application of a hinged joint of prismatic folds with supporting beams. It has been found that the chosenparameters of the second foundation model complied with the optimized results of the experiment planning and enabledto demonstrate the properties of the foundation system load redistribution better.

scholarly journals Increasing Damping of Thin-Walled Structures Using Additively Manufactured Vibration Eliminators

Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2125 ◽  
Author(s):  
Paweł Dunaj ◽  
Stefan Berczyński ◽  
Karol Miądlicki ◽  
Izabela Irska ◽  
Beata Niesterowicz
Keyword(s):  
Finite Element ◽  
Dynamic Stiffness ◽  
Experimental Studies ◽  
Steel Beam ◽  
Finite Element Models ◽  
Fem Model ◽  
Thin Walled Structures ◽  
Resonance Frequencies ◽  
Thin Walled ◽  
Parametric Analyses

The paper presents a new way to conduct passive elimination of vibrations consisting of covering elements of structures with low dynamic stiffness with polylactide (PLA). The PLA cover was created in 3D printing technology. The PLA cover was connected with the structure by means of a press connection. Appropriate arrangement of the PLA cover allows us to significantly increase the dissipation properties of the structure. The paper presents parametric analyses of the influence of the thickness of the cover and its distribution on the increase of the dissipation properties of the structure. Both analyses were carried out using finite element models (FEM). The effectiveness of the proposed method of increasing damping and the accuracy of the developed FEM models was verified by experimental studies. As a result, it has been proven that the developed FEM model of a free-free steel beam covered with polylactide enables the mapping of resonance frequencies at a level not exceeding 0.6% of relative error. Therefore, on its basis, it is possible to determine the parameters of the PLA cover. Comparing a free-free steel beam without cover with its PLA-covered counterpart, a reduction in the amplitude levels of the receptance function was achieved by up to 90%. The solution was validated for a steel frame for which a 37% decrease in the amplitude of the receptance function was obtained.

scholarly journals Measurements of Forces and Selected Surface Layer Properties of AW-7075 Aluminum Alloy Used in the Aviation Industry after Abrasive Machining

Materials ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 3707 ◽  
Author(s):  
Matuszak ◽  
Kłonica ◽  
Zagórski
Keyword(s):  
Surface Layer ◽  
Experimental Studies ◽  
Free Surface Energy ◽  
Aviation Industry ◽  
Spring Stiffness ◽  
Abrasive Machining ◽  
Thin Walled Structures ◽  
Axial Forces ◽  
Strongly Connected ◽  
Thin Walled

Measurements of forces during machining, especially thin-walled structures typical of the aviation industry, are important in the aspect of instability caused by vibration. One of the last stages of manufacturing by machining is the finishing treatment and deburring of the product’s edges. Brushes with ceramic fibres are often employed in deburring, especially for large-sized elements specific to the aviation industry due to the possibility of automatic machining directly on machining centres. This study set out to analyse the effect of variable brushing conditions on axial forces and the selected surface layer properties of AW-7075 aluminium alloy. Experimental studies have examined factors such as surface roughness and topography, axial cutting force in ceramic brush treatment and surface free energy in the aspect of adhesive joints. The tested variable process parameters were the fibre material and the adjustment sleeve spring stiffness. Based on the tests, it was found that the axial force applied by the brush was more strongly connected with the spring stiffness rather than the type of bristle. For most cases, an increase in the value of free surface energy after brushing was observed compared to the initial machining which was milling.

scholarly journals Experimental Methods in Psychology and Cognitive and Affective Neuroscience

Politik ◽  
2014 ◽  
Vol 17 (3) ◽  
Author(s):  
Thomas Habekost ◽  
Julie Hassing Nielsen
Keyword(s):  
Laboratory Experiments ◽  
Ecological Validity ◽  
Experimental Studies ◽  
Experimental Methods ◽  
Affective Neuroscience ◽  
International Psychology ◽  
Basic Principles ◽  
Social Perspectives ◽  
Recent Developments ◽  
Micro Level

Laboratory experiments have always been important in psychology and are as commonly used today as ever due to the dominating position of cognitive research in international psychology. is trend has been fur- ther strengthened by recent developments in cognitive neuroscience, where experimental studies are central. Recently, experimental studies within the eld of a ective neuroscience have also received attention. Not- withstanding, experimental methods remain controversial also in psychology, and one should carefully weigh their advantages against their drawbacks. is article provides an introduction to experimental psychology, including basic principles and illustrative examples. e article focuses on the experimental method in its purest form, the controlled laboratory study, and discusses the value of this scienti c approach with regard to ecological validity and socio-cultural factors. Furthermore, the article describes the use of experiments within cognitive and a ective neuroscience as well as the inherent challenges of individual versus social perspectives when conducting micro level laboratory experiments. 

Actual issues of hygienic regulation and creation of safe working conditions at pharmaceutical manufacturing enterprises

2020 ◽  
Vol 60 (10) ◽  
pp. 640-644
Author(s):  
Vadim M. Vasilkevich ◽  
Ruslan V. Bogdanov ◽  
Elena V. Drozdova
Keyword(s):  
Pharmaceutical Industry ◽  
Working Conditions ◽  
Experimental Studies ◽  
Pharmaceutical Products ◽  
Laboratory Animals ◽  
Production Environment ◽  
Basic Principles ◽  
Toxicological Studies ◽  
Health Disorders ◽  
Safe Working

Introduction. The working conditions of pharmaceutical industry workers are characterized by the combined effect of unfavorable factors of the production environment, among which the leading one is chemical. The aim of study is to substantiate the basic principles and criteria for hygienic regulation of pharmaceutical products in their production to ensure safe working conditions for employees based on the results of their own research and existing requirements of technical regulations. Materials and methods. Analysis of working conditions and the prevalence of health disorders in pharmaceutical workers (according to literature data), toxicological studies of pharmaceutical substances on laboratory animals, scientific justification of hygiene standards in the air of the working area. Results. Among employees of the pharmaceutical industry, the predominant forms of production-related health disorders are diseases of the respiratory system, as well as skin dermatitis of allergic origin, liver and biliary tract diseases. Based on the results of experimental studies of domestic pharmaceutical products for the treatment of cardiovascular, oncological and mental diseases that have priority socio-economic significance, the basic principles and features of the practice of justifying the hygienic standards of medicines in the air of the working area are developed and systematized. Conclusions. During hygienic rationing of medicines, it is necessary to use a differentiated approach that allows, based on the analysis of information about the chemical structure, physical and chemical characteristics, production conditions, pharmacotherapeutic activity, and the results of studying the toxic effect in an experiment on laboratory animals, to determine the maximum permissible content in the air of the working area of medicines or to justify the prohibition of isolation with reasoned recommendations for their safe production.

Frame-Monolithic Technology of Construction of Low-Rise Buildings Made of Foam Gypsum and Steel Thin-Walled Structures

2018 ◽  
Vol 762 (8) ◽  
pp. 36-39 ◽  
Author(s):  
B.G. BULATOV ◽  
◽  
R.I. SHIGAPOV ◽  
M.A. IVLEV ◽  
I.V. NEDOSEKO ◽  
...  
Keyword(s):  
Thin Walled Structures ◽  
Thin Walled

scholarly journals Formation of the Traffic Flow Rate under the Influence of Traffic Flow Concentration in Time at Controlled Intersections in Tyumen, Russian Federation

2021 ◽  
Vol 13 (15) ◽  
pp. 8324
Author(s):  
Viacheslav Morozov ◽  
Sergei Iarkov
Keyword(s):  
Traffic Flow ◽  
Flow Rate ◽  
Traffic Congestion ◽  
Traffic Management ◽  
System Analysis ◽  
Motor Vehicle ◽  
Experimental Studies ◽  
Transport Systems ◽  
Experiment Planning ◽  
Traffic Light

Present experience shows that it is impossible to solve the problem of traffic congestion without intelligent transport systems. Traffic management in many cities uses the data of detectors installed at controlled intersections. Further, to assess the traffic situation, the data on the traffic flow rate and its concentration are compared. Latest scientific studies propose a transition from spatial to temporal concentration. Therefore, the purpose of this work is to establish the regularities of the influence of traffic flow concentration in time on traffic flow rate at controlled city intersections. The methodological basis of this study was a systemic approach. Theoretical and experimental studies were based on the existing provisions of system analysis, traffic flow theory, experiment planning, impulses, probabilities, and mathematical statistics. Experimental data were obtained and processed using modern equipment and software: Traficam video detectors, SPECTR traffic light controller, Traficam Data Tool, SPECTR 2.0, AutoCad 2017, and STATISTICA 10. In the course of this study, the authors analyzed the dynamics of changes in the level of motorization, the structure of the motor vehicle fleet, and the dynamics of changes in the number of controlled intersections. As a result of theoretical studies, a hypothesis was put forward that the investigated process is described by a two-factor quadratic multiplicative model. Experimental studies determined the parameters of the developed model depending on the directions of traffic flow, and confirmed its adequacy according to Fisher’s criterion with a probability of at least 0.9. The results obtained can be used to control traffic flows at controlled city intersections.

Sign in / Sign up

Export Citation Format

Share Document