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Assessment of Traffic Noise Pollution Due to Urban Residential Road Transport

Abstract

The problem of combating urban noise is closely linked to the rational transformation of the urban environment, which must go through the elimination or reduction of the number of sources of noise, the localization of the noise emission zone, reducing the level of sound sources and protection against noise for the residential areas. Theoretical and experimental studies of acoustic loading on the territory along the highway for the typical section of the urban territory have been conducted. To estimate the complex noise impact from all sources and from individual sources, as well as to predict the total noise exposure for this site, a noise map was constructed using software. As a measure to combat traffic noise in the territory along the highway, the location of the noise protection screen was justified, taking into account the loss of part of the national income as a result of the continuous impact of noise on a person.The results of the research allow to assess the degree of technogenic impact of noise pollution during the operation of the highway, which allows regulating, by administrative and legislative methods, the nature of the impact on natural objects and human health of certain types of activities, as well as reasonably proposing measures that ensure environmental safety when organizing urban streets traffic.

Open access
Bicycle Level of Service Model for the Cycloruta, Bogota, Colombia

Abstract

Segment videos were produced at different peaks to reflect different sampling criteria like land use characteristics, trails, Ciclocarrils and Ciclovia. Each segment was filmed for 20–40 seconds during bicycle rides at a speed of about 5km/h with a camera strapped, at an angle of 45 degrees, on the head. Curb lane variables such as bicycle pathway widths, curb lane motorised volume (veh/h) and vehicle speed (km/h), bicycle volume on segment, and median width were recorded in addition to secondary data. About 1,360 ratings were acquired from study participants and used in the estimation process. Ordered probability models were used to estimate random parameters of cyclists LOS perception to account for unobserved heterogeneity for all respondents. The deviance (1.085) and Pearson Chi-Square (2.309) with 1,635 degree of freedom at 0.05 level of significance shows that our model provides a better fit of the data. The study observed that BLOS was strongly influenced by side path separation, vehicle speed, motorised traffic volume and conflicts with pedestrians. However, many other factors were found to have high probabilities to influence level of service with unit change. They include bicycle lane width, wide outside lane, pavement conditions, trees and benches, daylight, gender and experience of cyclist. The impact of the variety of observed factors affecting bicyclists reveal the nature and character of urban transportation in Bogota which suggests a range of important trade-offs in further planning and management of the Cicloruta bicycle paths.

Open access
Loessoid Soils Improvement – Laboratory Tests and Road Engineering Applications

Abstract

Moisture-sensitive or collapsible soils are materials with high porosity that under the loads transmitted by the superstructure or even under its own weight present additional settlements once the soil is saturated. This category includes loess deposits and other high silt content soils with uneven porosity. A method often used for foundation on these soils is the realization of local loessoid material compacted columns. This paper presents, on one hand, the experimental laboratory programs aiming to achieve some optimal mixtures of local material (loess) and different other materials (sand, bentonite, cement) in order to improve the values of the mechanical parameters of the soil and so, to limit the settlements. On the other hand, it presents a lot of settlement calculations for different case scenarios.

Open access
Reducing the Seismic Vulnerability for RC Buildings by Using Steel Bracing Elements

Abstract

This article aims to highlight, through a comparative study, the efficiency of steel bracing systems used to reduce seismic vulnerabilities in existing buildings with reinforced concrete structures (reinforced concrete frames and reinforced concrete dual structures, general building structures including those used in transport infrastructure). In order to simplify the calculations, the analysis was reduced to the study of the behavior of resistance lines corresponding to four-, nine- and fifteen-level buildings with the same plane distribution. In order to obtain features similar to those of existing building elements, structures were initially loaded with seismic forces corresponding to code P13-63. The next step was to apply to previously dimensioned structures the seismic loads according to P100-3: 2008 in relation to P100-1: 2013, thus obtaining the deficiencies of the existing structures against the requirements of these norms. Correction of these strength and stiffness deficiencies was attempted by introducing X-shaped centric brace systems. The bracing systems used as consolidation methods are of three types: direct bracings stuck in the reinforced concrete frames and bracings of the indirect type, made of internal and external bracing steel frames. Structural calculations were made in the linear elastic field using the ETABS program.

Open access
Study of the Influence of Fibres Type and Dosage on Properties of Concrete for Airport Pavements

Abstract

The paper follows the potential practice of fiber reinforced concrete (FRC) as a solution for airport`s runway pavements, in order to increase the bearing strength, resulting in decreasing the height of the concrete layer that is currently used.

Experimentally, the study focuses on the properties of fiber reinforced Portland cement concrete using 3 different percentages (0.5%, 1% and 1.5% of the concrete volume) and 4 different types of fiber (for 1% percentage – hooked steel fiber 50 mm length, hooked steel fiber 30 mm length, crimped steel fiber 30 mm length and polypropylene fiber 50 mm lenght), using as reference a plain concrete with 5 MPa flexural strength.

More exactly, the study presents the change in compressive and flexural strength, shrinkage, thermal expansion factor, elastic modulus and Poisson`s ratio over fiber type and dosage.

For the highest performance concrete (7 MPa flexural strength), it has been made a study using two methods for rigid airport pavements design (general method and optimized method), and one method for evaluation of bearing strength (ACN – PCN method), which is compared to a plain 5 MPa concrete. Furthermore, the decrease in the slab`s thickness proportionally to the growth of the flexural strength is emphasized by evaluating the slab`s height for a high performance 9 MPa concrete using both design methods.

Open access
The Use of Tuned Mass Dampers for Reducing Structural Vulnerabilities During the Side Movements of Buildings with Reinforced Concrete Frames

Abstract

The present article aims to point out, with the help of a comparative research, the efficiency of tuned mass dampers, modern variants of consolidation ensuring seismic structural safety, used for buildings with a reinforced concrete structure, designed and produced according to the new codes. Case studies were based on structural computations in the linear elastic field using the ETABS program.

Open access
Analysis of the implementation of the identification system for directly marked parts - DataMatrix code

Abstract

A photocode in Polish is a common name for a two-dimensional code, which is characterized by higher information capacity than a traditional barcode. The paper analyses the use of the two-dimensional coding system - DataMatrix to identify and classify the material stream in the production process. The analysis showed the effectiveness of the implementation of the coding system in the context of increased availability, machine use and increased product quality. The improvement in the production process is confirmed by an increase in the OEE index. As part of further improvement measures, the coding system should be implemented throughout the enterprise, its compatibility with existing systems should be ensured and applied to all products.

Open access
The delocalization of production to Poland

Abstract

This paper presents some aspects of the process of services, products and manufacturing transfer, with the associated production resources, from other locations and plants to Poland.

The study was carried out on the basis of an analysis of publications about delocalization as well as by means of desk research, where there were used the accessible primary and secondary data such as branch reports, statistical data available in reports, data bases, and information accessible on Polish and European websites. The article is also the result of the author's experience of participation in the relocation of a number of international companies, regarding various industries. Delocalization in Poland was presented both from the point of view of Conceptualizing delocalization (literature review, theoretical position) and Implementation of production.

The delocalization mainly takes advantage of labor forces. On the other hand, it may also concern innovative activities and develop high-tech for regions affected by economic restructuring. The social policies for the risk mitigation of the delocalization of production are also being developed and implemented. This work clarifying the conditions of delocalization in Poland and highlight the important roles played by innovation and institutions for achieving sustainability.

Open access
Electric aircraft - present and future

Abstract

In this paper, an outlook about the present of electrical aviation is given. The relatively small energy density of current battery technologies is adequate to build usable electric car, but not suitable for electric aircraft. Because of the very limited amount of energy available on-board, a couple of percent in efficiency can give significant increase in range and flight time, hence the development of more efficient propulsion system and E-motor is as important as the development of battery technologies. Current research results at the University of Dunaujvaros show, that building E-motors from amorphous materials is possible, and can easily increase the efficiency of high speed E-motors.

Open access
The impact of composition dependent and process-related properties in the laser cutting of metallic glassy tapes

Abstract

A short survey is reported on the advantageous and disadvantageous properties of soft magnetic glassy tapes to build stator and rotor elements for the increase of motor efficiency. The relative high saturation magnetization and the relative permeability of these alloy groups seem to be promising in this application field. On the other hand, the sample thickness (30 µm) displays limitations in terms of a filling factor. High hardness of tapes hinders the effectivity of mechanical shaping. Laser cutting can be successful as shaping method, presuming that the extension (thickness) of heat affected zone (HAZ) can be successfully reduced below 50µm, avoiding the brittleness evolution.

Open access