MATEC Web of Conferences

https://www.matec-conferences.org/

List of Papers (Total 7,301)

Evaluation of suitability for 3D printing of high performance concretes

The article presents overview of additive manufacturing for concrete structures. Study focuses on specific tests used to determine suitability of high performance mixes for 3D printing. The tests include determination of compressive strength and evaluation of printing speed, extrudability and overall surface quality. Tests were performed on a High-Performance Concrete mix with...

Preface

Neural network technique when distribution of vehicle component parts on the technological repair routes, taking into account their technical condition

Increase of repair efficiency is achieved due to the formation of centralized specialized production facilities which implement the vehicle component parts repair technique with the use of industrial technological processes to restore the technical state of the units and their components. In this case, the establishment of the expediency of sending the unit to repair, as well as...

Classification of Russian cities by levels of road traffic safety: specifics of required management decisions

The article considers the results of research of accident rate heterogeneity in cities-administrative centers of subjects of Russian Federation (2015, 2016). Using methods of ranging, regression analysis and spatial differentiation these cities were classified into 5 classes on the basis of relative disadvantage in road traffic safety sphere. For each group of cities...

Energy efficiency in municipal waste treatment

The article presents the efficient method of microwave irradiation (SHF) for the municipal liquid waste such as domestic wastewater and sludge. The technical and economic parameters and experimental data, showing the possibilities of microwave electromagnetic radiation using in the sewage and sediment treatment technologies, are given in this article. The traditional...

Tran boundary Pool of the Irtysh River: Problems’ Solutions of Municipal Facilities and Urban Development

The relevance of the study, due to the water difficult environmental situation increasing in the transboundary river basin (TRB) of Irtysh is related to the failure to address the issues of coordinated water use in the certain national segments: the Irtysh basin and its large left tributaries, the rivers Ishim and Tobol within the borders of Kazakhstan, China and Russia. The...

Evaluation of the Ecotoxicological State of Selected Soils from Urban Environments of Russian Arctic with the Aim to Substantiate Reclamation and Restoration Strategies

In recent decades rates of anthropogenic forcing on natural and urban ecosystems in the Arctic are increasingly growing. This tendency requires the development of more detailed environmental monitoring methods. In this context, study of background trace elements contents should be an urgent task. The purpose of authors study was an assessment of trace elements content in soils of...

University energy management improvement on basis of standards and digital technologies

Nowadays to implement the energy management system it is important to fulfill not only the legal requirements but also to follow the set of recommendations prepared by international and national management standards. The purpose of this article is to prepare the concept and methodology for the optimization and improvement of the energy management system (EMS) for Universities...

Estimation of the state of the road industry of Voronezh: ways of modernization and modern methods of its development

The paper is dedicated to the estimation of the state of the road economy of Voronezh up to date. The state of the Voronezh road system is analysed, statistical data are given, and the problems of the city transport system are studied. On the basis of all the data obtained, ways to solve existing problems are proposed and long-range programs for the construction of new and...

A selective study of Information technologies to improve operations efficiency in construction

Today, information technologies (IT) are used in almost every production industry. While the aspects of IT are well studied and discussed in relevant monographs, articles, web sources, etc., this paper reviews the performance improvement options in the construction industry by leveraging IT. From a wide range of information technologies the author has picked the most relevant...

State support mechanisms of small and midsize business entities

The article deals with the relevant problems of using state support mechanisms for the development of small and midsize business in Russia and the further usage of its competitive advantages at the present stage of the market economy functioning. Great attention is paid on the current condition of the development of small and midsize enterprises (the usage of state support tools...

Special aspects of technological entrepreneurship financing at the present stage

Technological entrepreneurship is a new trend of the world economy. The main sources of technological entrepreneurship financing are “business angels”, venture capital funds and innovative partnerships. The activation of innovative processes in the scientific and technical sphere becomes an important condition for the highly efficient economy creation. Today the search for...

Transactional costs of the interaction between business and government as a threat to the economic security of the state

The article considers the costs of the interaction between the state and business as a threat to the development of the economy of the Russian Federation from the point of view of ensuring economic security. The authors identified significant obstacles both from the business and from the government side, which pose a threat to economic security. The study is of interest for the...

Review of Energy Status and Associated Conservational Issues in Botswana

This paper discusses energy status of Botswana and the environmental concerns associated with the production of energy. It was offered in response to the growing concerns in industry about the need for the conservation of energy and for combating the increasing environmental degradation. Accomplishing vitality proficiency and diminishing ecological contamination are progressively...

Numerical Estimation of Notch Stress Intensity Factors of Sharp V-Notches

In the present work a simple and efficient least squares method is implemented for accurate estimation of notch stress intensity factors (NSIFs) of sharp V-notches. Finite element (FE) stress components near a notch tip is used in the present method for determining the NSIFs. Pure mode I and mixed mode (I/II) examples are considered for numerical investigations. The mixed mode...

Performance investigation of a rotary heat exchanger installed with four ducts using computational fluid dynamics

The performance characteristics of a commercially available rotary heat exchanger or were determined using CFD. A rotary air pre-heater of a thermal power plant (fuelled by natural gas), situated in Ramin, Iran, was numerically modelled with full scale dimensions using 3D approach. This model was then validated against the experimentally measured values. After a satisfactory...

Analytical Performance Analysis of Cross Flow Louvered Fin Automobile Radiator

The objective of the present paper is to propose an analytical model for calculating performance parameter of a radiator having rectangular tube with louvered fins. The theoretical effectiveness, heat transfer rate, outlet temperatures of both air and coolant are determined using effectiveness-NTU method. The coolant and air side pressure drop is also calculated. The proposed...

Crack growth behaviour of aluminium wrought alloys in the Very High Cycle Fatigue regime

Investigations have shown that in the regime of Very High Cycle Fatigue (VHCF) “natural” crack initiation often takes place underneath the material surface leading to crack propagation without contact to atmospheric components. In order to elucidate the environmental damage contribution and its effect on the VHCF long crack propagation, fatigue experiments with alternating...

Performance of chosen multiaxial cycle counting method under non-proportional multiaxial variable loading.

One of the most crucial tasks in fatigue life-time estimation of components loaded with multiaxial variable amplitude loading is to correctly identify loading cycles that can be used with multiaxial damage criterions. During past years, several cycle counting methods have been proposed for multiaxial loading conditions. The aim of this text is the comparison of selected...

Fatigue and fracture resistance of ferritic ductile cast iron: the effect of Sb and solidification time

In this paper, we explore the effect of inoculants and solidification time on the mechanical properties of an EN-GJS-400-type ferritic ductile cast iron (DCI). For this purpose, static tensile, rotating bending fatigue, fatigue crack growth and fracture toughness tests are carried out on three different material conditions. They are produced under fast cooling (solidification...

The relevance of non-stationarities and non-Gaussianities in vibration fatigue

In classical fatigue of materials, the frequency contents of dynamic loading are well below the natural frequencies of the observed structure or test specimen. However, when dealing with vibration fatigue the frequency contents of dynamic loading and structure's dynamic response overlap, resulting in amplified stress loads of the structure. For such cases, frequency counting...

Investigation of thermo-oxidative ageing effects on the fatigue design of automotive anti-vibration parts

Elastomeric parts found in automotive anti-vibration systems are usually massive. Ageing therefore leads to heterogeneous properties, usually induced by several mechanisms due to the availability, or not, of oxygen in the part’s bulk. To better understand the effects of oxygen in the degradation process and on the fatigue properties, this paper aims at studying the ageing of a...

Investigation of the fatigue behavior of notched reinforced thermoplastics

Understanding and modeling of fatigue damage and behavior in short glass fiber reinforced thermoplastics is an important issue in order to improve material processing and the design of composite parts for the industry. The present work aims at a more precise description of the fatigue damage mechanisms and the establishment of a simple, yet efficient, durability criterion...

Influence of the stacking fault energy and temperature on the prestrain memory effect of face centered cubic metal submitted to cyclic loadings

In this paper, the effect of a monotonic prehardening in tension on the subsequent cyclic stress strain curves is investigated as a function of the deformation mechanisms. To this aim, three materials are employed, copper for wavy dislocation slip, Ni20Cr alloy for planar slip and AISI 316L for intermediate deformation mechanisms. Samples were first prestrained in tension and...

Fatigue life time modelling of Cu and Au fine wires

In this study, the influence of microstructure on the cyclic behaviour and lifetime of Cu and Au wires with diameters of 25μm in the low and high cycle fatigue regimes was investigated. Low cycle fatigue (LCF) tests were conducted with a load ratio of 0.1 and a strain rate of ~2e-4. An ultrasonic resonance fatigue testing system working at 20 kHz was used to obtain lifetime...