scholarly journals Application of Knowledge of Fluid Mechanics in the Field of Design of Forming Tools

2020 ◽  
Vol 328 ◽  
pp. 03001
Author(s):  
Ján Moravec

The paper deals with the construction of a hydrostatic molding tool. The theoretical part presents the necessary knowledge about forming in liquid media. The experimental part presents the construction of a forming tool for drawing using a liquid. The discussion deals with environmental constraints of production processes.

1965 ◽  
Vol 20 (9) ◽  
pp. 1093-1102
Author(s):  
K. Möbius

It was the intention of this study to test the molecular orbital approximations of HÜCKEL and McLACHLAN by means of the experimental methods of EPR and polarography. In the experimental part problems are discussed as to electrolytic generation of free radicals and as to the ERP method with g-factors being measured with an accuracy of ± 2 ppm. In the theoretical part the molecular orbital theories of HÜCKEL and MCLACHLAN are summerized with particular regard to quantities which can be measured by EPR and polarography. A simple model of a σ → π → σ* excitation is developed which predicts a linear correlation between g-factor shift and π-energy of the lowest half-filled orbital. The validity of the model is discussed in terms of the g-factor theory recently deduced by STONE. The results of the experiments are presented in a subsequent paper.


2018 ◽  
Vol 168 ◽  
pp. 07003
Author(s):  
Ján Moravec

The application of liquid environment in forward extrusion is described in this paper. Theoretical part states findings from fluidic mechanics applied in the experimental part. Design solution of the tool is also presented. The experiments were done in laboratory conditions. The findings are stated with their limitations.


2013 ◽  
Vol 4 (1) ◽  
pp. 39-49
Author(s):  
Jukka Lintilä ◽  
Josu Takala

Abstract Most of the companies are interested in developing their production processes. With production process development, companies can meet their customers demands better. Tight competition is one reason that forces companies to use their production equipment as efficiently as they can. Improved production processes result in cost savings, flexibility, and in opportunities to plan companies activities more efficiently. The purpose of this research is to examine and cut operational times in food production processes. Two production lines were chosen for closer examination: spread/butter production line and quark production line. The main focus was to prevent operational time losses in these production lines. Research is divided into two separate sections: theoretical and empirical part. Theoretical part formulates guidelines and theoretical basis which is then employed in the empirical part. The theoretical part discusses Lean management philosophy, OEE indicator, SMED and questionnaire research method that comes from the sense and respond theory. In the empirical section, SMED and questionnaire method are used to examine operational activities. The focus is in finding critical characteristics from the production line’s starting-, product change-, and closing-setups. Result was that certain characteristics can be found to be critical factors. Those characteristics are connected to operational time losses. Another result is, that SMED and questionnaire research method are an effective way to examine issues with production. Both methods produced similar results in finding development targets from the production line, hence the simultaneous use of both is beneficial, as additional confirmation for the first methods findings can be obtained by securing the result with the other one.


1986 ◽  
Vol 24 ◽  
pp. 69-80
Author(s):  
H. Veenker

A pilot study is reported of the recognition of morphological and syntactic structures by prelingually totally deaf readers. The reading process is of importance because language acquisition takes place, among other things, through writing. The study was prompted by the question posed by Hung, Tzeng en Warren (1981): Why is it so difficult for deaf subjects to develop automaticity in recognizing printed English letters and words? This question was paraphrased as follows: How unambiguously are syntactic and morphological structures reflected in writing? In the theoretical part of the study it is argued that the -er suffix can be considered ambiguous. In the experimental part of the study the question was if, and to what extent, this ambiguity has psychological reality during the reading process of deaf subjects. Three questions were studied: 1. Is the subject able to recognise the suffix? 2. Is he able to affix correct connotations to it? 3. Is he able to give correct grammatical judgements about it? The results, based on an analysis of response delays and true/ false decisions, indicate that the deaf subjects do automatize, but in such a way that they systematically produce incorrect responses in certain spelling matters.


2012 ◽  
Vol 705 ◽  
pp. 7-25 ◽  
Author(s):  
Wonjung Kim ◽  
John W. M. Bush

AbstractWe examine the fluid mechanics of drinking in nature. We classify the drinking strategies of a broad range of creatures according to the principal forces involved, and present physical pictures for each style. Simple scaling arguments are developed and tested against existing data. While suction is the most common drinking strategy, various alternative styles have evolved among creatures whose morphological, physiological and environmental constraints preclude it. Particular attention is given to creatures small relative to the capillary length, whose drinking styles rely on relatively subtle interfacial effects. We also discuss attempts to rationalize various drinking strategies through consideration of constrained optimization problems. Some biomimetic applications are discussed.


Neofilolog ◽  
2019 ◽  
pp. 93-109
Author(s):  
Radosław Kucharczyk

The aim of this paper is to show the social representation of plurilingualism among students of French. The theoretical part of the paper presents definitions of plurilingualism used in sociolinguistics and foreign language didactics. The experimental part presents a survey conducted among the students, as well as a comparison of the results with the outcomes of a similar survey conducted in 2003, in order to indicate possible differences or changes in the didactic paradigm. The purpose of the study was to analyse the concept of plurilingualism, and to find to what extent students regard themselves as plurilingual.


2013 ◽  
Vol 4 (2) ◽  
pp. 78-88
Author(s):  
Jukka Lintilä ◽  
Josu Takala

Abstract Most of the companies are interested in developing their production processes. With production process development, companies can meet their customers demands better. Tight competition is one reason that forces companies to use their production equipment as efficiently as they can. Improved production processes result in cost savings, flexibility, and in opportunities to plan companies activities more efficiently. The purpose of this research is to examine and cut operational times in food production processes. Two production lines were chosen for closer examination: spread/butter production line and quark production line. The main focus was to prevent operational time losses in these production lines. Research is divided into two separate sections: theoretical and empirical part. Theoretical part formulates guidelines and theoretical basis which is then employed in the empirical part. The theoretical part discusses Lean management philosophy, OEE indicator, SMED and questionnaire research method that comes from the sense and respond theory. In the empirical section, SMED and questionnaire method are used to examine operational activities. The focus is in finding critical characteristics from the production line’s starting-, product change-, and closing-setups. Result was that certain characteristics can be found to be critical factors. Those characteristics are connected to operational time losses. Another result is, that SMED and questionnaire research method are an effective way to examine issues with production. Both methods produced similar results in finding development targets from the production line, hence the simultaneous use of both is beneficial, as additional confirmation for the first methods findings can be obtained by securing the result with the other one.


Author(s):  
Walter J. Sapp ◽  
D.E. Philpott ◽  
C.S. Williams ◽  
K. Kato ◽  
J. Stevenson ◽  
...  

Space flight, with its unique environmental constraints such as immobilization, decreased and increased pressures, and radiation, is known to affect testicular morphology and spermatogenesis. Selye, summarized the manifestations of physiological response to nonspecific stress and he pointed out that atrophy of the gonads always occurred. Reports of data collected from two dogs flown in space for 22 days (Cosmos 110) indicate that there was an increase of 30 to 70% atypical spermatozoa when compared to ground based controls. Seventy-five days after the flight the abnormalities had decreased to the high normal value of 30% and mating of these dogs after this period produced normal offspring, suggesting complete recovery. Effects of immobilization and increased gravity were investigated by spinning rats and mice at 2x g for 8-9 weeks. A decrease in testicular weight was noted in spun animals when compared to controls. Immobilization has been show to cause arrest of spermatogenesis in Macaca meminstrins.


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