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Libor Ižvolt, Peter Dobeš and Juraj Pieš

Abstract

The initial part of the paper briefly characterizes the present state of the track substructure dimensioning for the non-traffic load and the necessity of updating the design map of frost indexes IFd as a basis for dimensioning. A substantial part of the paper is dedicated to the method of evaluating the data provided by the Slovak Hydrometeorological Institute (SHMI), and determining the dependency of design air frost indexes IFd on altitude for the coldest winter period in the past 50 years. The paper conclusion presents the updated design map of frost indexes and the assessment of the importance of its updating in terms of the track substructure dimensioning methodology for the non-traffic load.

Open access

Rositsa Petkova-Slipets and Penka Zlateva

Abstract

The paper presents the results from a study of the thermo-physical properties of a new synthetic acrylic polymer used as material in road construction and as concrete on its basis. For the purposes of the study, the Modified Transient Plane Source Method (MTPS) was used. Data on the following thermal characteristics were obtained: thermal conductivity coefficient, thermal effusion, thermal diffusion and specific thermal capacity. A comparative analysis was made with the analogous indicators of conventional petroleum bitumen and asphalt concrete. The results of the study can be used for a more precise calculation and prognosis of temperature deformations and thermal stresses, as well as the crack propensity at low temperatures in asphalt concretes.

Open access

Zeynab Mohammadian and Majid Shahbazi

Abstract

Housing is a widespread and complex issue with a variety of dimensions. First, housing was considered as a physical location and as a shelter and basic necessity of the households, but today the concept of dwelling as the place that provides all the services and facilities necessary for a better life of the family has been created. One of the issues discussed at many conferences and in general in the scientific community is the definition of sustainability in the psychological point of view, along with the ways to introduce this concept into the architecture and human habitat environments. This research first begins with the main question about how the concept of sustainability can be found within the scope of housing. Then existing resources search is done and accessible projects are analyzed and the weaknesses and strengths of traditional architecture and contemporary architecture are compared. Finally, the relationship between the definitions of three concepts: dwelling, sustainable design and traditional Iranian architecture was discussed. At the end, the sustainable design that is also appropriate to the Iranian culture was presented.

Open access

Veronika Valašková and Jozef Vlček

Abstract

This article illustrates the applicability of the Finite Element Method (FEM) in the analysis of multi-layer concrete pavement systems subjected to tire loading of a heavy vehicle. For the purpose of simplifying the interaction of the interaction system, it is appropriate to divide the system into two separate independent subsystems, the vehicle and the pavement. For this reason, 2-dimensional interaction model of the contact vehicle-obstacle and 3-dimensional FEM model of the concrete pavement were created. A several constitutive material models, such as linear elastic model, are applied in the analysis to describe the behaviour of the pavement structure. The numerical results from the first computational model can be used as the input for the second calculation phase. The concrete pavement represents a standard pavement, which is used for the regular road structures in road engineering. FEM modelling of the pavement can be used for the direct estimation of the pavement response without performing time and cost expensive field experiments. Calculations were performed in software ADINA using FEM method.

Open access

Mária Kúdelčíková and Eva Merčiaková

Abstract

In structural dynamics models of mechanical oscillator and vibration analysis are of great importance. In this article motion of mechanical oscillator is modelled using second order linear autonomous differential systems. Stability of such 1 DOF models is investigated with respect to the coefficients of systems. Phase portraits for various cases are displayed and the character of fixed points is described.

Open access

Filiz Ersoz, Taner Ersoz and Muhammet Soydan

Abstract

Construction sector has an important place in Turkey’s economy. Real estate sales for the sector are increasing in parallel. However, the purchase cost is also important for those who are willing to buy a real estate. In the acquisition of real estate, factors such as size, location and age of the house are taken into consideration. The aim of the article is to conduct research on factors affecting real estate values by data mining. In this study, the most important variables that determine the value of the real estate have been investigated by data mining methods. The research has been carried out in Karabük and the variables determined according to the opinions of real estate experts. As classification methods, CHAID and C&RT algorithms have been used. It has been evaluated that both algorithm estimation results can be used. Within the framework of the study, the variables that have the most impact on the unit price have been determined, such as the size of the real estate, the distance to the city centre, the popularity, and the age of the building. The use of advanced technologies, such as statistical modelling and machine learning in real estate valuation and automatic value estimation, is of importance in determining the real value of the real estate.

Open access

Taner Ersoz, Filiz Ersoz and Deniz Merdin

Abstract

Widespread usage of the internet and computers have facilitated a number of human resource management activities such as compensation management, performance management, vocational training and other personnel management affairs across various enterprises. It is known that the employment of a qualified labour force becomes increasingly difficult due to increasing competition conditions. Therefore, it is important to ensure that the right person is recruited for the enterprise and that he/she is attached to his/her employer. Thanks to information technologies, the recruitment process can be implemented more quickly and effectively. The present study aims at determining whether the employer-employee has a sense of trust; whether employee’s performance, disciplinary action, reporting status and significant inconvenience status are taken into account by an enterprise in the iron and steel industry. Logistic regression method is used as an analysis method. The effects of the demographic variables on the dependent variables are also determined. Considering the results obtained, it is observed that the loyalty of the employees to the employer is not very strong, but at the level of improvement, the employees do not consider working at the company for many years.

Open access

Alexander Tsatsulin

Abstract

The forthcoming transfer of St. Isaac’s Cathedral in St. Petersburg being a UNESCO World Heritage Site to the Russian Orthodox Church ignites a heated debate within the Russian society. The cathedral being part of the State Museum Complex stands out as a pearl of the world’s iconic architecture. Furthermore, it is the second most visited museum after the Hermitage, boasts an outstanding exhibition potential, and it regularly hosts church services and ritual events. Museum collections exceed twenty-four thousand items of storage, and they continue to be replenished with found rarities and newly restored objects with the status of a relic to be protected. The aim of the article is to measure the value of the assets of the monument building, assessing the insured value of the object. Uncertainty of the future use of the disputed object, however, allows us to consider the calculation capabilities and methodical tools of valuation activities to measure the market and insurance value of such a real estate object and land plot, for example, in order to practice damage compensation and transfer the object from the balance sheet of one owner to balance of another owner. The latter circumstance determines the main discourse of this study. The present article is devoted to questions of an expert estimation of the insured value of the object of research in the form of St. Isaac’s Cathedral. The article is a continuation of a series of previously published works by the author.

Open access

Andrey Benin and Ekaterina Bogdanova

Abstract

A trend of applying composite reinforcement in construction industry has been growing in Russia recently: hence, new manufacturing plants have appeared and the volume of sales has increased. However there were not enough experimental studies of the polymer reinforcement chemical stability and the influence of various factors (climate, corrosive environments, nonstationary loading, etc.) on the strength of structures reinforced with polymer rebars. The objective of this investigation was to identify the influence of long-term storage conditions and exposure to corrosive environment (i.e. 5 % NaCl solution) produced on the mechanical properties of GFRP rebars.

Open access

Ivo Gulbis

Abstract

The paper aims at providing insight into the effectiveness of Latvian special economic zones (SEZ) as a tool to attract foreign direct investment (FDI). The goal is accomplished through the statistical analysis of relevant data and the comparison with international examples to establish a point of reference. Countries of comparison are chosen by merit, in the form of widely acknowledged success stories regarding SEZ policy, and relative statistical similarity. The wider the pool of examples, the more conclusions can be drawn about the effectiveness of SEZ in various metrics. Based on the results, Latvian special economic zones have significantly underperformed when compared to every single example on the list. Research has been approbated in the Riga Technical University 58th International Scientific Conference “Scientific Conference on Economics and Entrepreneurship” (SCEE’2017).