scholarly journals Simulation of the Thermoforming Process of Glass Fiber Reinforced Polymeric Components: Investigation of the Combined Effect of the Crosshead Speed and Material Temperature

2021 ◽  
Author(s):  
Antonios Stamopoulos ◽  
Antoniomaria Di Ilio ◽  
Luca Glauco Di Genova
Keyword(s):  
Elevated Temperatures ◽  
Thickness Distribution ◽  
Mechanical Tests ◽  
Point Of View ◽  
Material Behavior ◽  
Thermoplastic Composite ◽  
Residual Stress Field ◽  
Crosshead Speed ◽  
Thermoforming Process

Abstract Thermoplastic based composite materials are increasingly gaining the interest of many engineering sectors, among them the automotive. Their unique features, resulted by the thermoplastic matrix characteristics, such as their recyclability and their formability have given new perspectives in their use. Among the most promising fabrication methods of thermoplastic composite components is the thermoforming process, the press forming of a heated semi-finalized composite plate. This method, although requires a quite simple working station and can be implemented in mass production, demonstrates a series of disadvantages on the quality of the product. Among them, the variation of the thickness, formation of wrinkles and overall undesired deformations are considered as defects that decrease the quality not only from the esthetical but also from the structural point of view. In the present work, a numerical analysis of the thermoforming process is conducted when applied to a box-shaped geometry. As an input for the material behavior during the process, mechanical tests are conducted at elevated temperatures. The flat and curved critical zones of the component are identified and an analysis of the effect of the temperature and the crosshead speed of the molds on the thickness distribution are examined as well as the overall residual stress field. The results indicate a strong dependency of the quality of the product by these parameters of the process.

The Quality of Brazed Ceramic and Cemented Carbide Joints - A Mechanical and Metallurgical Assessment

2010 ◽  
Vol 64 ◽  
pp. 108-114 ◽  
Author(s):  
Wolfgang Tillmann ◽  
Lukas Wojarski ◽  
Benjamin Lehmert
Keyword(s):  
Thermal Stresses ◽  
Mechanical Performance ◽  
Ceramic Materials ◽  
Mechanical Tests ◽  
Point Of View ◽  
Cemented Carbides ◽  
Full Potential ◽  
Ceramic Surface ◽  
Reaction Products

The availability of adequate joining technologies is of major importance in order to exploit the full potential of ceramic materials. The same is true for joints between cemented carbides and their counterparts. Such joints are not easy to manufacture due to wetting and bonding problems as well as induced thermal stresses. Currently, active brazing is a potential approach for fabricating such joints. The filler alloy contains reactive agents such as Titanium or Hafnium etc. that interact by forming wettable reaction layers on the ceramic surface. It is self-evident that they function very well on cemented carbides as well. The paper describes potential wetting and bonding reactions from a metallurgical point of view. Ceramics, superabrasive and cemented carbides are investigated with respect to interfacial reactions. The quality of the reaction products is of crucial importance regarding the mechanical performance of the joints, as their immanent brittleness can lead to a significant weakening. Apart from metallurgical assessments, mechanical tests are conducted in order to deliver data for their integration in hybrid structures. FE methods can be applied to assess the stress situation in the final joint. Thus it is possible to adjust the design accordingly.

scholarly journals Computer simulation of thermoforming process and its verification using a rapid tooling mould

2018 ◽  
Vol 157 ◽  
pp. 02032
Author(s):  
Michał Modławski ◽  
Tomasz Jaruga
Keyword(s):  
Computer Simulation ◽  
Thickness Distribution ◽  
Rapid Tooling ◽  
Fused Deposition Modelling ◽  
Fused Deposition ◽  
Poly Ethylene Terephthalate ◽  
Thermoforming Process ◽  
Poly Ethylene ◽  
Tooling Technology

The results of computer simulation of thermoforming process made using ANSYS Polyflow software are presented in this paper. The analysis of the wall thickness distribution across an U-shaped thermoformed product manufactured using a positive mould was made. The simulation results were verified using a mould manufactured in a 3D printing process which was Fused Deposition Modelling (FDM) and a poly(ethylene terephthalate) formed sheet. It was proven that the computer simulation and a tool made with a Rapid Tooling technology can be useful for predicting the quality of a thermoformed part, particularly to find the problems with thin-walled areas.

COMBINATORIAL POLYNOMIALLY COMPUTABLE CHARACTERISTICS OF SUBSTITUTIONS AND THEIR PROPERTIES

2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  
Keyword(s):  
Mathematical Expectation ◽  
Point Of View ◽  
Small Range ◽  
Computational Point ◽  
Wide Range ◽  
Bijective Function ◽  
The Difference ◽  
Element Base ◽  
Selection Of

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.

Physical capital stock, technological upgrading and modernisation in Hungary

2005 ◽  
Vol 55 (2) ◽  
pp. 201-221 ◽  
Author(s):  
Andrea Szalavetz
Keyword(s):  
Capital Accumulation ◽  
Physical Capital ◽  
Developed Countries ◽  
Point Of View ◽  
Technology Generation ◽  
Development Policies ◽  
Specific Factors ◽  
Physical Capital Accumulation

This paper discusses the relation between the quality and quantity indicators of physical capital and modernisation. While international academic literature emphasises the role of intangible factors enabling technology generation and absorption rather than that of physical capital accumulation, this paper argues that the quantity and quality of physical capital are important modernisation factors, particularly in the case of small, undercapitalised countries that recently integrated into the world economy. The paper shows that in Hungary, as opposed to developed countries, the technological upgrading of capital assets was not necessarily accompanied by the upgrading of human capital i.e. the thesis of capital skill complementarity did not apply to the first decade of transformation and capital accumulation in Hungary. Finally, the paper shows that there are large differences between the average technological levels of individual industries. The dualism of the Hungarian economy, which is also manifest in terms of differences in the size of individual industries' technological gaps, is a disadvantage from the point of view of competitiveness. The increasing differences in the size of the technological gaps can be explained not only with industry-specific factors, but also with the weakness of technology and regional development policies, as well as with institutional deficiencies.

Flouride and Nitrate Status of Some Ground Waters in Chittor District of Rajasthan State (India)

2018 ◽  
Vol 6 (9) ◽  
pp. 119
Author(s):  
Trapti Sharma ◽  
R. P. Nagar ◽  
R. C. Gaur ◽  
Pooja Gupta ◽  
Charanjit Kaur
Keyword(s):  
Point Of View ◽  
World Health ◽  
Indian Council ◽  
Standard Methods ◽  
Ground Waters ◽  
Drinking Waters ◽  
Health Organization ◽  
Research World ◽  
Drinking Purpose

In Rajasthan state the ground waters of some areas like Ramganj-mandi, Morak, Barmer, Jaisalmer, Chittor and Udaipur etc. are susceptible from drinking point of view.To test the quality of groundwater in Chittor district 14, ground water samples were collected from various places and analyzed for pH, E.C., Fluoride and Nitrate parameters by standard methods (A.P.H. A., Washington, USA, 1995). The study revealed that none of the ground waters was found suitable completely from drinking point of view. Some are having electrical conductivity > 1.4 dS/m, some are having pH >8.5, some area having fluoride >1.5 ppm and some are having nitrate>45 ppm. These are the limits of various parameters permitted by various International authorities like Bureau of Indian Standard, Indian Council of Medical Research,world health Organization etc. for drinking waters. So, it is recommended to the residents of above areas to use water for drinking purpose only after reverse osmosis or adopting suitable method of removing excess of Fluoride and Nitrate for drinking water to avoid unwanted pathogenic diseases harmful for human health.

A Futures Study on the Quality Of Life from the Point Of View of Iranian Youth

2017 ◽  
Vol 14 (2) ◽  
pp. 1
Author(s):  
Sina Saeedy ◽  
Mojtaba Amiri ◽  
Mohammad Mahdi Zolfagharzadeh ◽  
Mohammad Rahim Eyvazi
Keyword(s):  
Quality Of Life ◽  
Life Satisfaction ◽  
Mixed Model ◽  
Satisfaction With Life ◽  
Point Of View ◽  
Human Society ◽  
Futures Studies ◽  
The Social ◽  
The University

Quality of life and satisfaction with life as tightly interconnected concepts have become of much importance in the urbanism era. No doubt, it is one of the most important goals of every human society to enhance a citizen’s quality of life and to increase their satisfaction with life. However, there are many signs which demonstrate the low level of life satisfaction of Iranian citizens especially among the youth. Thus, considering the temporal concept of life satisfaction, this research aims to make a futures study in this field. Therefore, using a mixed model and employing research methods from futures studies, life satisfaction among the students of the University of Tehran were measured and their views on this subject investigated. Both quantitative and qualitative data were analysed together in order to test the hypotheses and to address the research questions on the youth discontentment with quality of life. Findings showed that the level of life satisfaction among students is relatively low and their image of the future is not positive and not optimistic. These views were elicited and discussed in the social, economic, political, environmental and technological perspectives. Keywords:  futures studies, quality of life, satisfaction with life, youth

FUNDAMENTAL AND APPLIED SCIENTIFIC RESEARCH: сб.науч.тр./ OEAPS Inc.; редкол.: Флора Бертран (отв.ред.) [и др.]. - Берлин, Германия : OEAPS Inc., 2018. - 58 С.

2018 ◽  
Author(s):  
Мария Григорьевна Алпатова ◽  
Мария Игоревна Щеглова ◽  
Elmira Kalybaevna Adil’bekova ◽  
Nuradin Alibaev ◽  
Arunas Svitojus
Keyword(s):  
Service Sector ◽  
Applied Research ◽  
Point Of View ◽  
Scientific Quality ◽  
Final Decision ◽  
Main Criterion ◽  
The Public ◽  
Peer Reviewers ◽  
Verification Process

The conference is a major international forum for analyzing and discussing trends and approaches in research in the field of basic science and applied research. We provide a platform for discussions on innovative, theoretical and empirical research. The form of the conference: in absentia, without specifying the form in the collection of articles. Working languages: Russian, English Doctors and candidates of science, scientists, specialists of various profiles and directions, applicants for academic degrees, teachers, graduate students, undergraduates, students are invited to participate in the conference. There is one blind verification process in the journal. All articles will be initially evaluated by the editor for compliance with the journal. Manuscripts that are considered appropriate are then usually sent to at least two independent peer reviewers to assess the scientific quality of the article. The editor is responsible for the final decision on whether to accept or reject the article. The editor's decision is final. The main criterion used in assessing the manuscript submitted to the journal is: uniqueness or innovation in the work from the point of view of the methodology being developed and / or its application to a problem of particular importance in the public sector or service sector and / or the setting in which the efforts, for example, in the developing region of the world. That is, the very model / methodology, application and context of problems, at least one of them must be unique and important. Additional criteria considered in the consideration of the submitted document are its accuracy, organization / presentation (ie logical flow) and recording quality.

FUNDAMENTAL AND APPLIED SCIENTIFIC RESEARCH April 2019: сб.науч.тр./ OEAPS Inc.; редкол.: Флора Бертран (отв.ред.) [и др.]. - Берлин, Германия : OEAPS Inc., 2019. - 98 C.

2019 ◽  
Author(s):  
Изабелла Станиславовна Чибисова ◽  
Диана Ильгизаровна Шарипова ◽  
Альфия Галиевна Зулькарнаева ◽  
Ксения Александровна Дулова ◽  
Садег Амирзадеган ◽  
...  
Keyword(s):  
Service Sector ◽  
Applied Research ◽  
Point Of View ◽  
Scientific Quality ◽  
Final Decision ◽  
Main Criterion ◽  
The Public ◽  
Peer Reviewers ◽  
Verification Process

The conference is a major international forum for analyzing and discussing trends and approaches in research in the field of basic science and applied research. We provide a platform for discussions on innovative, theoretical and empirical research. The form of the conference: in absentia, without specifying the form in the collection of articles. Working languages: Russian, English Doctors and candidates of science, scientists, specialists of various profiles and directions, applicants for academic degrees, teachers, graduate students, undergraduates, students are invited to participate in the conference. There is one blind verification process in the journal. All articles will be initially evaluated by the editor for compliance with the journal. Manuscripts that are considered appropriate are then usually sent to at least two independent peer reviewers to assess the scientific quality of the article. The editor is responsible for the final decision on whether to accept or reject the article. The editor's decision is final. The main criterion used in assessing the manuscript submitted to the journal is: uniqueness or innovation in the work from the point of view of the methodology being developed and / or its application to a problem of particular importance in the public sector or service sector and / or the setting in which the efforts, for example, in the developing region of the world. That is, the very model / methodology, application and context of problems, at least one of them must be unique and important. Additional criteria considered in the consideration of the submitted document are its accuracy, organization / presentation (ie logical flow) and recording quality.

Tertiary Nitrification Pilot Plants on Parisian Waste Water

1990 ◽  
Vol 22 (1-2) ◽  
pp. 347-352 ◽  
Author(s):  
C. Paffoni ◽  
B. Védry ◽  
M. Gousailles
Keyword(s):  
Waste Water ◽  
Metropolitan Area ◽  
Fixed Bed ◽  
Point Of View ◽  
Operating Conditions ◽  
Research Center ◽  
Daily Output ◽  
Practical Point ◽  
Fixed Bed Reactors

The Paris Metropolitan area, which contains over eight million inhabitants, has a daily output of about 3 M cu.meters of wastewater, the purification of which is achieved by SIAAP (Paris Metropolitan Area Sewage Service) in both Achères and Valenton plants. The carbon pollution is eliminated from over 2 M cu.m/day at Achères. In order to improve the quality of output water, its tertiary nitrification in fixed-bed reactors has been contemplated. The BIOFOR (Degremont) and BIOCARBONE (OTV) processes could be tested in semi-industrial pilot reactors at the CRITER research center of SIAAP. At a reference temperature of 13°C, the removed load is approximately 0.5 kg N NH4/m3.day. From a practical point of view, it may be asserted that in such operating conditions as should be at the Achères plant, one cubic meter of filter can handle the tertiary nitification of one cubic meter of purified water per hour at an effluent temperature of 13°C.

Monumentality and the Roman Empire

2007 ◽  
Author(s):  
Edmund Thomas
Keyword(s):  
Roman Empire ◽  
Early Modern ◽  
Point Of View ◽  
Full Length ◽  
Classical Antiquity ◽  
Early Modern Europe ◽  
Close Link ◽  
The Public ◽  
Roman Italy

The quality of "monumentality" is attributed to the buildings of few historical epochs or cultures more frequently or consistently than to those of the Roman Empire. It is this quality that has helped to make them enduring models for builders of later periods. This extensively illustrated book, the first full-length study of the concept of monumentality in Classical Antiquity, asks what it is that the notion encompasses and how significant it was for the Romans themselves in molding their individual or collective aspirations and identities. Although no single word existed in antiquity for the qualities that modern authors regard as making up that term, its Latin derivation--from monumentum, "a monument"--attests plainly to the presence of the concept in the mentalities of ancient Romans, and the development of that notion through the Roman era laid the foundation for the classical ideal of monumentality, which reached a height in early modern Europe. This book is also the first full-length study of architecture in the Antonine Age--when it is generally agreed the Roman Empire was at its height. By exploring the public architecture of Roman Italy and both Western and Eastern provinces of the Roman Empire from the point of view of the benefactors who funded such buildings, the architects who designed them, and the public who used and experienced them, Edmund Thomas analyzes the reasons why Roman builders sought to construct monumental buildings and uncovers the close link between architectural monumentality and the identity and ideology of the Roman Empire itself.

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