scholarly journals INCREASING THE RIGIDITY OF THE SELF-CENTERING DEVICES OF LATHES

2021 ◽  
Vol 6 (2) ◽  
pp. 100-106
Author(s):  
A. Seregin ◽  
I. Nikitina ◽  
S. Krylova
Keyword(s):  
Load Distribution ◽  
Structural Changes ◽  
Engineering Problem ◽  
The Self ◽  
Elastic Displacement ◽  
Adjacent Pair ◽  
Complex Engineering ◽  
Technical Solutions ◽  
Rack Mechanism ◽  
Positive Results

Increasing the rigidity of universal self-centering devices is one of the topical trends in the design of machine tooling. Calculation of the load distribution between the turns and teeth of a spiral rack and pinion mechanism is a complex engineering problem. When working on the article, it was revealed that an adjacent pair of turns and teeth that are in engagement does not always coincide with a geometrical adjacent pair due to the error in the execution of turns and teeth along the pitch and profile. This is based on experimental data and the proposition that errors in the pitch and profile of the spiral determine the nature of the working pressures in the engagement of the turns and teeth. The article discusses technical solutions in which the rigidity of self-centering devices increases without significant structural changes due to the establishment of the correspondence of the algorithm for changing the elastic properties of parts of the spiral-rack mechanism to the algorithm for changing the load between the bearing elements. Constructive solutions based on the implementation of elastic displacement of the first most loaded turn are proposed, which allows to reduce the interference between the tooth of the cam rack and the turn of the disk spiral. This circumstance contributes to the redistribution of the load in the engagement of the bearing elements of the spiral-rack mechanism. The tests of the developed structures were carried out, which gave positive results.

St. Petersburg industrial policy: Determining the factors of structural changes in industry through Shift-Share Analysis

2020 ◽  
Vol 18 (5) ◽  
pp. 909-939
Author(s):  
M.V. Dement'ev
Keyword(s):  
Industrial Policy ◽  
Structural Transformation ◽  
Mechanical Engineering ◽  
Manufacturing Industry ◽  
Structural Changes ◽  
Analysis Method ◽  
Factor Analyses ◽  
Further Development ◽  
Positive Results

Subject. This article examines the theoretical and practical aspects of the implementation of industrial policy and the structural transformation of the manufacturing industry in St. Petersburg. Objectives. The article aims to justify the priority of the industry-based approach to industrial policy in St. Petersburg and determine its effectiveness by highlighting the factors of structural transformation of the city's manufacturing industry using the Shift-Share Analysis method. Methods. For the study, I used logical, statistical, and factor analyses. Results. Based on shift-share analysis, the study highlights positive results of industrial policy in the development of certain industries in St. Petersburg, as well as those industries that require further development of urban industrial policy. Conclusions. Despite the fact that the industry of St. Petersburg as a whole has become more stable, problems in the development of mechanical engineering and production of computers, electronic and optical products have not yet been solved.

scholarly journals Gray-Matter Expansion of Social Brain Networks in Individuals High in Public Self-Consciousness

2021 ◽  
Vol 11 (3) ◽  
pp. 374
Author(s):  
Tomoyo Morita ◽  
Minoru Asada ◽  
Eiichi Naito
Keyword(s):  
Gray Matter ◽  
Structural Changes ◽  
Gray Matter Volume ◽  
Brain Networks ◽  
Japanese Version ◽  
Brain Regions ◽  
The Self ◽  
Social Brain ◽  
Default Mode ◽  
Public Self Consciousness

Self-consciousness is a personality trait associated with an individual’s concern regarding observable (public) and unobservable (private) aspects of self. Prompted by previous functional magnetic resonance imaging (MRI) studies, we examined possible gray-matter expansions in emotion-related and default mode networks in individuals with higher public or private self-consciousness. One hundred healthy young adults answered the Japanese version of the Self-Consciousness Scale (SCS) questionnaire and underwent structural MRI. A voxel-based morphometry analysis revealed that individuals scoring higher on the public SCS showed expansions of gray matter in the emotion-related regions of the cingulate and insular cortices and in the default mode network of the precuneus and medial prefrontal cortex. In addition, these gray-matter expansions were particularly related to the trait of “concern about being evaluated by others”, which was one of the subfactors constituting public self-consciousness. Conversely, no relationship was observed between gray-matter volume in any brain regions and the private SCS scores. This is the first study showing that the personal trait of concern regarding public aspects of the self may cause long-term substantial structural changes in social brain networks.

scholarly journals What can engineers learn from the past? A potential role for history in engineering education.

2013 ◽  
Vol 2 (2) ◽  
pp. 43-54 ◽  
Author(s):  
Andrea Gaynor ◽  
Greg Crebbin
Keyword(s):  
Problem Solving ◽  
Engineering Students ◽  
Potential Role ◽  
Energy Transport ◽  
Engineering Problem ◽  
Historical Narratives ◽  
Engineering Practice ◽  
The Past ◽  
Technical Solutions ◽  
Ecologically Sustainable

At present, in many societies, engineers play a significant role in solving problems of energy, transport, accommodation and production; but similar problems have been solved through technical and non-technical means for thousands of years. Numerous historical examples therefore exist, in which the ends of different approaches to problem-solving are apparent: some tending to produce socially and/or ecologically sustainable outcomes, and some less positive. Historians do not simply narrate the past, they explain and interpret changes and continuities by paying attention to larger issues of, for example, class, gender, polity and economy. Such historical narratives, we argue, may have a useful role to play in efforts to shift the perspective of engineering students away from a narrow focus on complex technical solutions, towards the broader context in which their problem-solving will take place. This ability to assess the relationships between engineering problem-solving and the broader social and environmental context is critical to the development of a more sustainable and socially-just engineering practice.

Frontiers in Engineering Optimization

1983 ◽  
Vol 105 (2) ◽  
pp. 151-154 ◽  
Author(s):  
J. T. Betts
Keyword(s):  
Mathematical Programming ◽  
Engineering Problem ◽  
Theory And Practice ◽  
Programming Algorithm ◽  
Engineering System ◽  
Engineering Optimization ◽  
Complex Engineering ◽  
Optimization Operator

The successful application of a mathematical programming algorithm to a complex engineering problem requires a careful interfacing of needs and requirements between the optimization operator and the engineering system. This paper outlines some areas where interface requirements have not been successfully resolved. In order to bridge the frontier between theory and practice, issues are identified which require resolution by both algorithm developers and system engineers.

Degradation of wood constituents during the self-agglomeration of an oak sawdust. II. Infrared study of two lignins

1968 ◽  
Vol 46 (11) ◽  
pp. 1893-1902 ◽  
Author(s):  
Henry P. Naveau
Keyword(s):  
Aromatic Ring ◽  
Structural Changes ◽  
The Self ◽  
Infrared Spectrophotometry ◽  
Infrared Study

Structural changes in lignins isolated from particle-boards are studied by infrared spectrophotometry, in relation to an endothermic trend which characterizes the self-agglomeration process.Changes in intensity of various infrared bands are reported and are attributed to the following: (a) variation in the nature and distribution of substituents of the aromatic ring and conjugation of the aromatic ring with carbonyl C=O or C=C, which indicate an increasing state of condensation of the lignin, (b) simultaneous division of the macromolecule of lignin, partially caused by breakage of ether linkages between its lateral chains, (c) cleavage of bonds between lignin and carbohydrate material, and (d) insolubilization, with the acid lignin, of an increasing amount of carbohydrate material which is also increasingly condensed.The origin of the endothermic trend cannot be explained in terms of these reactions of lignin.

scholarly journals Employment Relationships in Dairy Farming - Psychological Contracts Reconsidered

1970 ◽  
Author(s):  
Rupert Tipples ◽  
Nona Verwood
Keyword(s):  
Structural Changes ◽  
Dairy Farming ◽  
Psychological Contracts ◽  
The Self ◽  
The Other ◽  
Common Denominator ◽  
Employment Relationships ◽  
Widespread Adoption ◽  
The Common

The essence of psychological contracting (in the contest of employment) is meeting mutual expectations. The common denominator between legal contracting and psychological contracting is that both are designed to express expectations of the self and of the other. Legal expectations lead to outcomes that are observable, measureable and usually quantifiable. Psychological expectations are usually invisible but nonetheless very real.This paper expresses the need for greater attentions to psychological contracting in a dairy sector going through substantial structural changes involving the replacement of self-employed farmers by hired managers and contract milkers and the widespread adoption of once-a-day milking.

Study on Complex Structure Mesh Generating of Hexahedron Element Based on Improved Waveform Mesh Generating Method

2011 ◽  
Vol 462-463 ◽  
pp. 955-960
Author(s):  
Xu Fei Wang ◽  
Mamtimin Gheni ◽  
Masanori Kikuchi ◽  
Ju Rong Liu
Keyword(s):  
Mesh Generation ◽  
Complex Structure ◽  
Fem Simulation ◽  
Engineering Problem ◽  
Simulation Technique ◽  
Tetrahedral Mesh ◽  
Hexahedral Mesh ◽  
Generating Method ◽  
Complex Engineering ◽  
Mesh Models

Three-dimensional finite element method (FEM) is widely used as an effective numerical simulation technique to solve the complex engineering problem. Usually, the more complex engineering problem has more complex structure and shape; the FEM simulation technique is that needs to discrete the structure and shape of the problem by mesh. In addition, the correct generation of mesh is one of the most significant issues that directly affect to the accuracy of the FEM simulation. The hexahedral mesh is better than tetrahedral mesh in solving the complex engineering problem. The common methods of hexahedral automatic mesh generation have been used in some commercial soft already, but its adaptation is not enough to solve for practical applications of the complex engineering problems. A new method of mesh generation technique was proposed by improved waveform mesh generating method, and realized by C++ developing program in Linux OS. The method could generate some effective and smoothly mesh models by quadrilateral element or hexahedron element, and not only generated revolution curve surface meshes, but also generated random meshes according to free functions too. The results shown that the hexahedral mesh models of the complex shapes were generated as the shape function apply to regular mesh side as a waveform constraint.

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