scholarly journals Clarification of Features of the Wheel Movement with a Perspective Constructive Scheme on a Rail

2020 ◽  
Vol 10 (19) ◽  
pp. 6758
Author(s):  
Evgeny Mikhailov ◽  
Stanislav Semenov ◽  
Sergii Kliuiev ◽  
Ján Dižo ◽  
Miroslav Blatnický ◽  
...  
Keyword(s):  
Support Surface ◽  
Relative Rotation ◽  
Friction Forces ◽  
Slippage Rate ◽  
Common Axis ◽  
Design Scheme ◽  
Axis Of Rotation ◽  
Traditional Design ◽  
Curved Track

The article presents the continuation of studies of the features of the wheel movement the traditional and perspective constructive scheme on a rail. Unlike the traditional design, the perspective constructive scheme of the wheel allows independent relative rotation of the support surface wheel and of its guide surface (flange) relative to their common axis of rotation. Previous authors’ works did not take into account the influence of the level of slippage in the main contact of the wheel with the rail on the value of the slippage rate in its flange contact. This article further examines the influence of this factor for both wheel designs. The results of the presented studies confirm the possibility of reducing slippage in the flange contact with the rail for a wheel of a promising design scheme in comparison with a traditional wheel. Reducing the power of friction forces in the contact of the wheel flange of a promising design scheme will reduce the resistance to movement of such a wheel along the rail, especially in curved track sections.

The Design of Water Saving System for College Dorms

2012 ◽  
Vol 518-523 ◽  
pp. 3672-3675
Author(s):  
Bin Li
Keyword(s):  
Water Use ◽  
Water Saving ◽  
Special Structure ◽  
Ozone Generator ◽  
Design Scheme ◽  
Subsidence Area ◽  
Traditional Design ◽  
Water Collection ◽  
Different Color ◽  
Saving Effect

We designed a set of water saving system for college dorms based on the current college water use status. This system mainly included a water collection tank and the enclosed sanitary-wares. We designed the subsidence area on one side of the water collection tank so it’s easy to clean the sludge and the allocation of water-saving effect demonstration system. There are no devices in the water collection tank for eliminating the peculiar smell of wastewater, heterochromatic carbon absorber and ozone generator. In order to ensure the smooth implementation of the system, in view that the peculiar smell and different color of the wastewater affecting users mood, in order to reduce the users conflicted emotion, according to the shortage of current toilet sanitary-wares,we designed an enclosed squats bedpan that using the user’s gravity to expansion and it will be closed automatic when users left. We also designed an enclosed toilet that using the user’s gravity to expansion and it will be closed automatic when users left. And we designed an enclosed urinal that using the user’s gravity to expansion and it will be closed automatic when users left. And according to the lower pressure situation of the upper water collection tank, the special structure of the squats bedpan and toilet in this project don't need a large scouring force, rejected the “siphon principle” that widely used in the traditional design scheme, reduce the required water, improve water saving effect.

scholarly journals A Cold-Pressing Method Combining Axial and Shear Flow of Powder Compaction to Produce High-Density Iron Parts

Technologies ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 70 ◽  
Author(s):  
Grigoriev ◽  
Dmitriev ◽  
Korobova ◽  
Fedorov
Keyword(s):  
Material Flow ◽  
Axial Loading ◽  
Powder Compaction ◽  
Friction Forces ◽  
Pressing Method ◽  
Cold Pressing ◽  
Traditional Design ◽  
Active Friction ◽  
Set Up ◽  
Active Friction Forces

Highly performance methods for cold pressing (cold die forging) of preforms from iron powder with subsequent heat treatment and producing ready parts made of powder are described in the paper. These methods allow fabricating parts with smooth surfaces and improved mechanical characteristics—porosity, tensile strength. Application of the traditional design set-up with a single-axial loading is restricted to high stresses in the dies to deform the preforms that lead to cracks formation. New powder compaction schemes by applying active friction forces (shear-enhanced compaction) make it possible to unload dies and produce high-quality parts by cold pressing. The scheme allows moving the die in the direction of the material flow with a velocity that exceeds the material flow velocity.

Two-lobed artificial cardiac valve with a common axis of rotation of lobes

1998 ◽  
Vol 32 (5) ◽  
pp. 272-282 ◽  
Author(s):  
V. N. Yurechko ◽  
R. V. Yurechko ◽  
L. M. Vil'danov ◽  
M. P. Etonov
Keyword(s):  
Cardiac Valve ◽  
Common Axis ◽  
Artificial Cardiac Valve ◽  
Axis Of Rotation

scholarly journals STABILITY OF VIBRATIONS OF THE TRACTOR AS A TWO-MASS MODEL WITH TWO NONLINEARITIES OF THE TYPE OF DRY FRICTION IN RESONANCE MODES

2021 ◽  
Author(s):  
E. Kalinin ◽  
◽  
Y. Kolesnik ◽  
M. Myasushka
Keyword(s):  
Differential Equations ◽  
Dry Friction ◽  
System Analysis ◽  
Nonlinear Differential Equations ◽  
Support Surface ◽  
Systems Methodology ◽  
Friction Forces ◽  
Resonance Modes ◽  
At Resonance ◽  
Relative Friction

Purpose of the study is to assess the possibility of calculating the stability of tractor oscillations as a system with nonlinearities such as dry friction due to the inverse problem. Research methods. The methodological basis of the work is the generalization and analysis of known scientific results regarding the dynamics of two-mass systems in resonance modes and the use of a systematic approach. The analytical method and comparative analysis were used to form a scientific problem, determine the goal and formulate the research objectives. When creating empirical models, the main provisions of the theory of stability of systems, methodology of system analysis and research of operations were used. The results of the study. Oscillations of the system with harmonic excitation by its base are considered (for example, the movement of a tractor on an uneven supporting surface). Oscillations of this system are described by nonlinear differential equations. To solve this equation, instead of friction dampers with friction forces, linear dampers with corresponding drag coefficients are included in the system. By solving the obtained system of linear inhomogeneous differential equations for the steady-state mode of oscillation, the amplitudes of oscillations of masses and deformation of springs with certain stiffness are determined. To clarify the effect of friction forces on mass oscillations in resonance modes, the obtained expressions were analyzed. A diagram of stability of mass oscillations in resonance modes is obtained. Conclusions. It has been established that if the coefficients of relative friction have such values that the point that is determined by them lies within the region bounded by segments 1-2 and 2-3 and coordinate axes, then during oscillations in the low-frequency resonance mode, the friction forces do not limit the increase in amplitudes fluctuations of masses, but only reduce the rate of their growth. If the point, which is determined by the coefficients of relative friction, lies in the region 1-1'-2'-3 '3-2-1, then the springs have intermittent deformation, that is, during the period of oscillation, one mass of the system has stops relative to another mass, or the last has stops relative to the support surface, or both masses move part of the period as a whole with the support surface. At resonance with a high frequency, the friction forces limit the amplitudes of mass oscillations if the coefficients of relative friction have such values that the point that is determined by them does not lie in the region bounded by segments 4-5 and 5-6 and the coordinate axes. Sections 4-5 and 5-6 define the boundaries of vibration stability at resonance (lines of critical ratios of the coefficients of relative friction).

The Equivalence of Two Classical Problems of Free Spinning Gyrostats

1971 ◽  
Vol 38 (3) ◽  
pp. 707-708 ◽  
Author(s):  
R. E. Roberson
Keyword(s):  
Fixed Point ◽  
Constant Angular Velocity ◽  
The Body ◽  
The Other ◽  
Relative Rotation ◽  
Dynamical Equations ◽  
Interaction Torque ◽  
Axis Of Rotation ◽  
Free Body ◽  
Internal Rotor

Two problems of a torque-free body with a fixed point are considered. In both the body is rigid but for an internal rotor symmetric about its axis of rotation. In one the rotor is driven at a constant angular velocity, in the other the interaction torque between body and rotor has a zero component on the axis of relative rotation. The dynamical equations are shown to have exactly the same structure. A brief literature summary on the torque-free gyrostat is appended.

scholarly journals Improvement of warehouse hovercraft transport devices with inclined feed channels

2021 ◽  
pp. 58-66
Author(s):  
V. A. Turushin ◽  
◽  
A. M. Redko ◽  
N. V. Turushina ◽  
◽  
...  
Keyword(s):  
Operating Costs ◽  
Support Surface ◽  
Total Resistance ◽  
Problem Statement ◽  
Friction Forces ◽  
Logistics Enterprises ◽  
Storage Area ◽  
Load Location ◽  
And Storage ◽  
Transport Device

Introduction. The paper considers the question of the directions of mechanization and automation of rack warehouses logistics. The paper considers hovercraft transport devices operating in the storage area with inclined feeding channels. The displacement of the load center relative to the geometric center of the support surface is studied. It is noted how this affects the main characteristics of the studied devices. Problem Statement. Previous studies have proved the sufficient performance of non-powered hovercraft transport devices with inclined feed channels, their safety and efficiency in the transportation of piece goods, as well as the potential for mechanization and automation of transport and storage operations in rack warehouses. The task of this work is to present a scheme of mechanization for the storage area of a rack warehouse equipped with a transport device with inclined feeding channels. Theoretical Part. In rack warehouses designed for the storage of individual goods, the receiving, storing and sending operations are in most cases carried out using carrying and lifting machines. Stacker cranes are most common, but their use requires the creation of complex and expensive systems, i.e. significant capital and operating costs. The article considers the system of mechanization of a rack warehouse with the use of hovercraft vehicles with an off-center location of the cargo. In this case, the height of the airbag depends on the eccentricity of the load location. The points of application and the values of the resistance and traction forces, torques and friction forces that affect the total resistance are shown, which are typical for such a situation Conclusion. The results of the research allow us to state that in some cases, instead of traditional transport devices, the use of hovercraft transport devices with the inclined feed channels is effective in logistics enterprises.

scholarly journals Research on the Application of Computer in the Design of Arts and Crafts

2021 ◽  
Vol 290 ◽  
pp. 02025
Author(s):  
Zhengjuan Hu
Keyword(s):  
Computer Technology ◽  
Design Methods ◽  
Product Performance ◽  
Design Stage ◽  
Arts And Crafts ◽  
Design Scheme ◽  
Scheme Optimization ◽  
Traditional Design ◽  
Traditional Arts ◽  
Early Preparation

Firstly, this paper expounds the design methods of traditional arts and crafts, including the traditional design methods of sculpture crafts, glass crafts and ceramic crafts. Then it analyzes the advantages of computer technology in the design of arts and crafts, including improving the product performance of arts and crafts, improving the design interest of arts and crafts designers and improving the modern flavor of arts and crafts; then it expounds the application of computer technology in different stages of arts and crafts design in detail, including the early preparation, concrete implementation, design scheme optimization and in-depth design stage; Finally, it analyzes the specific application of computer technology in arts and crafts design, including the application of computer technology in sculpture crafts design, glass crafts design and ceramic tea set modeling design.

scholarly journals Study on combined machine for the subsurface soil treatment

2021 ◽  
Vol 939 (1) ◽  
pp. 012065
Author(s):  
Kh Ravshanov ◽  
F Mamatov ◽  
B Mukimov ◽  
R Sultonov ◽  
A Abdullayev ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Classical Mechanics ◽  
Design Scheme ◽  
Axis Of Rotation ◽  
Subsurface Soil ◽  
Transverse Distance ◽  
Winter Crops ◽  
Free Body ◽  
Working Bodies ◽  
Longitudinal Distance

Abstract The purpose of the study is to substantiate the relative position of the working bodies of a combined machine for non-fall tillage of winter crops. The design scheme and the principle of operation of the combined machine are given. The basic principles and methods of classical mechanics, mathematical analysis and statistics were used in this study. It is established that the most optimal design scheme of a combined machine for non-tillage of the soil and its preparation for sowing of repeated crops is considered to be a scheme consisting of non-tillage cases with crushers, a battery with cut-out spherical disks and a roller. According to the results of theoretical and experimental studies, it was found that with a longitudinal distance between the shaft-free bodies of 40 cm and a transverse distance of 90 cm, a longitudinal distance from the toe of the ploughshare to the center of the support wheel of 50 cm and a longitudinal distance from the toe of the ploughshare of the shaft-free body to the axis of rotation of the cut-out spherical disk of 120 cm, a longitudinal distance from the axis of rotation of the cut-out spherical disk to the center of the roller of 75 cm, high-quality tillage with minimal energy costs is provided.

On Variations in the Chandler Frequency

1972 ◽  
Vol 1 ◽  
pp. 77-85
Author(s):  
H.J.M. Abraham ◽  
J.N. Boots
Keyword(s):  
Axis Of Rotation ◽  
The Earth ◽  
Actual Motion ◽  
Chandler Frequency

This paper suggests that some of the reported changes in the Chandler frequency are associated with inelastic changes in the Earth. There has been controversy as to how much of the apparent secular polar drift is due to actual motion of the axis of rotation within the Earth, and how much it is merely the reflection of movements by certain observatories. Therefore, when more southern data are available it will be interesting to see whether similar results are obtained.

Reference Coordinate System Requirements for Geophysics

1975 ◽  
Vol 26 ◽  
pp. 87-92
Author(s):  
P. L. Bender
Keyword(s):  
Coordinate System ◽  
Polar Motion ◽  
Main Part ◽  
Measurement Techniques ◽  
Reference Points ◽  
Angular Motion ◽  
Coordinate Systems ◽  
Axis Of Rotation ◽  
The Earth ◽  
Fixed System

AbstractFive important geodynamical quantities which are closely linked are: 1) motions of points on the Earth’s surface; 2)polar motion; 3) changes in UT1-UTC; 4) nutation; and 5) motion of the geocenter. For each of these we expect to achieve measurements in the near future which have an accuracy of 1 to 3 cm or 0.3 to 1 milliarcsec.From a metrological point of view, one can say simply: “Measure each quantity against whichever coordinate system you can make the most accurate measurements with respect to”. I believe that this statement should serve as a guiding principle for the recommendations of the colloquium. However, it also is important that the coordinate systems help to provide a clear separation between the different phenomena of interest, and correspond closely to the conceptual definitions in terms of which geophysicists think about the phenomena.In any discussion of angular motion in space, both a “body-fixed” system and a “space-fixed” system are used. Some relevant types of coordinate systems, reference directions, or reference points which have been considered are: 1) celestial systems based on optical star catalogs, distant galaxies, radio source catalogs, or the Moon and inner planets; 2) the Earth’s axis of rotation, which defines a line through the Earth as well as a celestial reference direction; 3) the geocenter; and 4) “quasi-Earth-fixed” coordinate systems.When a geophysicists discusses UT1 and polar motion, he usually is thinking of the angular motion of the main part of the mantle with respect to an inertial frame and to the direction of the spin axis. Since the velocities of relative motion in most of the mantle are expectd to be extremely small, even if “substantial” deep convection is occurring, the conceptual “quasi-Earth-fixed” reference frame seems well defined. Methods for realizing a close approximation to this frame fortunately exist. Hopefully, this colloquium will recommend procedures for establishing and maintaining such a system for use in geodynamics. Motion of points on the Earth’s surface and of the geocenter can be measured against such a system with the full accuracy of the new techniques.The situation with respect to celestial reference frames is different. The various measurement techniques give changes in the orientation of the Earth, relative to different systems, so that we would like to know the relative motions of the systems in order to compare the results. However, there does not appear to be a need for defining any new system. Subjective figures of merit for the various system dependon both the accuracy with which measurements can be made against them and the degree to which they can be related to inertial systems.The main coordinate system requirement related to the 5 geodynamic quantities discussed in this talk is thus for the establishment and maintenance of a “quasi-Earth-fixed” coordinate system which closely approximates the motion of the main part of the mantle. Changes in the orientation of this system with respect to the various celestial systems can be determined by both the new and the conventional techniques, provided that some knowledge of changes in the local vertical is available. Changes in the axis of rotation and in the geocenter with respect to this system also can be obtained, as well as measurements of nutation.

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