scholarly journals STRENGTH ANALYSIS OF SCREW CONVEYOR DRIVE

2021 ◽  
Vol 2021 (6) ◽  
pp. 5488-5491
Author(s):  
TOMAS CORANIC ◽  
◽  
JOZEF MASCENIK ◽  
Keyword(s):  
Structural Unit ◽  
Strength Characteristics ◽  
Screw Conveyor ◽  
Strength Analysis ◽  
Structural Units ◽  
Theoretical Part ◽  
Theoretical Assumptions ◽  
Manufacturing Engineering ◽  
The Given ◽  
Manufacturing Machine

The present paper deals with research of strength characteristics in manufacturing engineering. The introduction of the work describes findings about the importance of the given subject. The publication is divided into two basic parts, namely the theoretical and the practical part. The theoretical part provides a detailed description of theoretical assumptions on solutions in the field of research, and it also describes optimization of structural units in manufacturing engineering, while the practical part analyses strength characteristics of the selected structural unit which is the drive of a manufacturing machine. The conclusion of the work presents the obtained results.

scholarly journals Formation of integrated structural units using the systematic and integrated method when implementing high-rise construction projects

2018 ◽  
Vol 33 ◽  
pp. 03075 ◽  
Author(s):  
Ivan Abramov
Keyword(s):  
Construction Projects ◽  
Structural Unit ◽  
System Analysis ◽  
Research Priorities ◽  
Structural Units ◽  
Factors Affecting ◽  
Reliability Criterion ◽  
Integrated Method ◽  
Destabilizing Factors ◽  
The Impact

Development of design documentation for a future construction project gives rise to a number of issues with the main one being selection of manpower for structural units of the project’s overall implementation system. Well planned and competently staffed integrated structural construction units will help achieve a high level of reliability and labor productivity and avoid negative (extraordinary) situations during the construction period eventually ensuring improved project performance. Research priorities include the development of theoretical recommendations for enhancing reliability of a structural unit staffed as an integrated construction crew. The author focuses on identification of destabilizing factors affecting formation of an integrated construction crew; assessment of these destabilizing factors; based on the developed mathematical model, highlighting the impact of these factors on the integration criterion with subsequent identification of an efficiency and reliability criterion for the structural unit in general. The purpose of this article is to develop theoretical recommendations and scientific and methodological provisions of an organizational and technological nature in order to identify a reliability criterion for a structural unit based on manpower integration and productivity criteria. With this purpose in mind, complex scientific tasks have been defined requiring special research, development of corresponding provisions and recommendations based on the system analysis findings presented herein.

Structural variation in wollastonite and bustamite

1985 ◽  
Vol 49 (350) ◽  
pp. 37-48 ◽  
Author(s):  
R. J. Angel
Keyword(s):  
Structural Unit ◽  
Structural Variation ◽  
Relative Displacement ◽  
Single Type ◽  
Stacking Sequence ◽  
Structural Units ◽  
Ordered Structures ◽  
Unit Cells ◽  
Line Defects

AbstractThe structures of bustamite and the poly-types of wollastonite are shown to be derived from variations in the stacking sequence of a single type of structural unit. This structural unit is a column of unit cells of wollastonite along the b-axis and is bounded by (100) and (001) planes (P1̄ cell); these units may be stacked together along [100] and [001] with either zero displacement between successive units, or a relative displacement of 1/2[010]. Regular stacking sequences give rise to the ordered structures of wollastonite polytypes and of bustamite, while the transformations between these structures proceed by the propagation of line defects with Burgers vectors of 1/2[010] which thus change the stacking sequence of the structural units.

scholarly journals The Kinematic Analysis of the Screw Conveyor Vibration Exciter

2019 ◽  
Vol 297 ◽  
pp. 03004
Author(s):  
Dmitriy Kobylyansky ◽  
Viacheslav Gogolin
Keyword(s):  
The Body ◽  
Calculation Scheme ◽  
Polar Coordinates ◽  
Screw Conveyor ◽  
Vibration Exciter ◽  
System Of Equations ◽  
Harmonic Oscillations ◽  
Triangle Center ◽  
The Given ◽  
Rotating Bodies

The article presents a method of calculating the parameters of the screw conveyor vibration exciter. The calculation scheme of the new design of the vibration exciter, which allows to determine the parameters of the vibrations excited by this device taking into account the structural novelty and the specifics of the vibration exciter, in particular, in the screw reloader is also given. A system of equations describing the harmonic oscillations of the auger shaft axis, including the amplitudes of horizontal and vertical oscillations, is presented. As a result, a system of parametric equations describing the external and internal envelope line is obtained. When solving the system of equations, the equations of the boundary curves of internal and external rotating bodies are derived. The equations allow to calculate the trajectory of any point by its given polar coordinates. Examples of rotating bodies for different types of displacements of the triangle center in the calculation scheme, which are described by harmonic oscillations, are shown. The dependences of the body shape on the direction of oscillations along the coordinate axes are illustrated. It is shown that the transition from horizontal to vertical oscillations leads to a loss of symmetry of the body. The amplitude and frequency of oscillations also have a significant impact on the shape of the body. The forms of the rotating bodies, giving the possibility of combining the rotation and oscillation when driving on rollers are determined. The problem is generalized to an arbitrary number of regularly arranged rollers. The given technique gives the principal opportunity to create designs of vibrators that combine vibrations with rotation on rollers.

scholarly journals The structure of Artemia sp. (brine shrimp) haemoglobins. Purification of a structural unit to homogeneity

1985 ◽  
Vol 227 (3) ◽  
pp. 917-924 ◽  
Author(s):  
L Moens ◽  
M L Van Hauwaert ◽  
G Wolf
Keyword(s):  
Brine Shrimp ◽  
Structural Unit ◽  
Single Type ◽  
Structural Units ◽  
Limited Digestion

The extracellular haemoglobins (Mr 260 000) of the brine shrimp Artemia sp. were cleaved by limited digestion with subtilisin. Structural units of Mr 16 000, which can bind dioxygen reversibly, were isolated. Analysis of the 16 000-Mr fraction (E) reveals the presence of a limited number of structural units. A single type of structural unit, E1 (Mr 15 800; pI4.8), was purified to homogeneity and characterized.

In Situ Test Study on Shear Strength Properties of Weathered Silty Mudstone

2010 ◽  
Vol 146-147 ◽  
pp. 10-13 ◽  
Author(s):  
Zhang Ming Li ◽  
Liang Liang Chen ◽  
Feng Wu ◽  
Ling Wan
Keyword(s):  
Shear Strength ◽  
Maximum Shear Stress ◽  
Strength Properties ◽  
Strength Characteristics ◽  
Shear Strength Parameters ◽  
Silty Mudstone ◽  
Normal Loading ◽  
Test Study ◽  
The Given

The shear strength characteristics of rock are very concerned in related underground construction. In this paper, in situ direct shear test for the weathered silty mudstone of the direct rock mass in a large section tunnel is carried out, the shear strength parameters are obtained, and some laws on the strength characteristics of this rock are got, such as that the displacement corresponds to the maximum shear stress under the given normal is decreased with increasing of normal loading number. This work provides a reference for the study of rock strength theory and its application.

scholarly journals The Content Form of the Lexeme “Average”: Synchrony and Diachrony

2015 ◽  
pp. 250-254
Author(s):  
T. A. Svetonosova
Keyword(s):  
Research Methods ◽  
English Language ◽  
Lexical Semantics ◽  
English For Specific Purposes ◽  
Theoretical Part ◽  
Diachronic Analysis ◽  
British National Corpus ◽  
The Given ◽  
National Corpus

Why can a word in the English language have various meanings? As a rule, such queries arise in English for General Purposes classes and their number is increasing in English for Specific Purposes classes. The word average is learnt in both above-mentioned classes and it is evident that it has different meanings. It is worth noting that not all these meanings can be found in monolingual dictionaries. Watching the usage of the word average while teaching has led to the given article. The synchronic and diachronic analysis of the content form of the lexeme average as the noun is conducted in the article. The theoretical part embraces points of semantics development, lexical semantics notions as well as concepts and definitions of semantics terms used in this article. Then the reasons for choosing the lexeme average are stated, the goal of the article is set, the research methods are provided. The practical part covers the synchronic and diachronic contexts in which the lexeme average operates - data from the British National Corpus, entries from monolingual dictionaries, materials from coursebooks, entries from etymological dictionaries. All these contexts are analyzed and inferences about the content form of the lexeme average are made. At the end of the article further possible research of the lexeme average is outlined.

scholarly journals RELATIVE DISTANCE: THE KEY TO THE SHAPE OF HEPATIC BUILDING BLOCKS

2011 ◽  
Vol 19 (1) ◽  
pp. 19 ◽  
Author(s):  
Jan M Ruijter ◽  
Marry M Markman ◽  
Jaco Hagoort ◽  
Antoon FM Moorman ◽  
Wouter H Lamers
Keyword(s):  
Portal Vein ◽  
Mouse Liver ◽  
Structural Unit ◽  
Building Blocks ◽  
Relative Volume ◽  
Central Vein ◽  
Terminal Branch ◽  
Relative Area ◽  
Structural Units ◽  
Relative Radius

The delineation and the shape of the smallest structural units of the liver is still the subject of debate. However,the blood flow from an upstream terminal branch of the portal vein to a downstream central vein is thought to induce a functional zonation in hepatocyte gene expression. This property was used to determine boundary conditions for the shape of the hepatic building blocks. Histochemical techniques that specifically label periportally or pericentrally expressed enzymes can be used to distinguish periportal and pericentral areas in a liver section. Pairs of images from aligned serial sections, one stained for a portal and the next for a central enzyme, are used. Segmentation and skeletonisation of these images results in the skeletons of the portal and central areas. Distance transformation with respect to these skeletons gives for each point in the image pair the distance to the nearest terminal branches of the portal vein and the central vein. For each point the relative position on the porto-central radius can then be calculated as its distance to a portal vein divided by the sum of its portal and its central distance. In the resulting relative radius image, the area occupied by 'zones' of equivalent relative radius can be measured. According to the principle of Delesse the relative area of a zone in the image is equal to the relative volume of that zone in the tissue. For structural units of plate-like, cylindrical or spherical shape, the relative volume of a zone is equal to the relative radius of that zone to the power 1, 2 or 3, respectively. Thus, the exponent in the relative area - relative radius relation gives information on the shape of the structural unit. Measurement of the areas of each relative radius zone and determination of the area - radius relation in images of random sections of adult mouse liver results in an exponent of 1.1. This suggests that the smallest structural unit of the mouse liver has the shape of a needle.

The structure of a near Σ=27 tilt grain boundary in Ge

1992 ◽  
Vol 50 (1) ◽  
pp. 214-215
Author(s):  
Stuart McKernan ◽  
C. Barry Carter
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Structural Unit ◽  
Perfect Crystal ◽  
Boundary Plane ◽  
Boundary Structure ◽  
Structural Units ◽  
Grain Boundary Plane ◽  
Grain Boundary Structure ◽  
Complex Structural

The modeling of tilt grain boundaries in terms of repeating structural units of varying separation is now a well established concept. High-resolution electron microscope (HREM) images of different tilt grain boundaries in many materials display a qualitative similarity of atomic configurations of the grain boundary structure. These boundaries are frequently described in terms of characteristic structural units, which may be separated from each other by regions of ‘perfect’ crystal (as, for example, in low-angle grain boundaries), or may be contiguous, forming ordered arrays of the structural units along the boundary. In general there will be a different arrangement of the structural units or an arrangement of different structural units, according to the precise geometry of the particular grain boundary. The structure of some special grain boundaries has been examined and these are found to exist in several different configurations, depending on the orientation of the grain boundary plane among other parameters. Symmetry-related symmetric tilt grain boundaries and asymmetric tilt grain boundaries with one grain having a prominent, low-index facet, are commonly observed, low-energy configurations. Structural multiplicity of these configurations along the same grain boundary has been observed in some systems. Defects in the perfect ordering of the structural units may be caused by deviations of the grain boundary plane away from the perfect tilt orientation. Deviations of grain boundary structure away from the exact orientation will also produce defects in the repeating structural unit configuration. These deviations may have a regular and well-defined structure, producing a more complex structural unit.

Bias deployable grids with horizontal compound scissor-like elements: A geometric study of the folding/deployment process

2021 ◽  
pp. 095605992110640
Author(s):  
Manuel J Freire-Tellado ◽  
Manuel Muñoz-Vidal ◽  
Juan Pérez-Valcárcel
Keyword(s):  
Structural Unit ◽  
Kinematic Model ◽  
Three Dimensional ◽  
Angular Distortion ◽  
Structural Units ◽  
Load Bearing ◽  
Stable Structures ◽  
Geometric Study

Bias deployable structural units are two-way structures arranged in a rotational pattern with respect to the edges. They have interesting advantages such as robust three-dimensional operation with supports around their entire base perimeter and the exclusive use of load-bearing scissor-like elements (SLEs). However, they do not have edge trims and their resistance to angular distortion is limited. This article proposes a series of deployable bi-stable structures that address these problems and incorporate new, resilient features. A method of analysing the incompatibilities of the structural unit is developed based solely on the geometric study of the deployment process, which allows the level of incompatibility of the proposal to be graduated, varying from stress-free structures to bi-stable structures. A kinematic model of one of the proposals allows the research undertaken to be contrasted.

The Prestige of Sport and Sport as a Source of Prestige

2021 ◽  
Vol 28 ◽  
pp. 13-18
Author(s):  
Zbigniew Dziubiński
Keyword(s):  
Social Sciences ◽  
Social Control ◽  
Informal Social Control ◽  
Interesting Issue ◽  
Descriptive Term ◽  
Social Sanctions ◽  
Theoretical Assumptions ◽  
Sporting Activities ◽  
Social Interactionism ◽  
The Given

The aim of the study is an attempt to characterise prestige as an important descriptive term, explaining the phenomena and processes occurring in (post-) modern sport and to answer the question regarding the sources of sport prestige and sport as a source of prestige. The work is based on an analysis of the literature on the given subject in the fi eld of humanities and social sciences, especially sociology, devoted to the interesting issue of prestige and sport. In the analysis,the dominant scientifi c theories were implemented, including, inter alia, structural and functional, social interactionism, Weber’s and Warner’s theory of prestige, and the theoretical assumptions of Henryk Domański and Piotr Sztompka. Through the analyse, it is shown that sport itself, in relation to other areas of life, enjoys relative prestige. Access to the stock of prestige in sport is unequal. Some disciplines, sporting activities, sport groups and individuals have greater access to it, while others do not. Sport in (post-) modern societies is a source of prestige. This is confi rmed by the pro-sport nature of informal social control, as a result of which, participation in sport is subject to positive social sanctions, while lack of such participation is deprived of such sanctions.

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