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In recent years, numerous studies have confirmed the vital role and therapeutic potential of quaternary ammonium compounds and endogenous formaldehyde in the prevention and treatment of diseases. These compounds participate in the transmethylation processes and play a role in the metabolism and in the regulation of cellular processes. The present research indicates that sour cherry fruit contains large quantities of quaternary ammonium compounds in the early developmental phase (burgeoning). The quantity of methyl-donor compounds (choline, carnitine) and easily mobilizable methyl groups were measured in various fruit parts (stalk, fruit flesh, seed kernel) of five sour cherry cultivars using OPLC technology, and the cultivar dependence of the detected compounds was examined. The results of comparative examinations established the presence of choline in the stalk and seed and of a significant amount of carnitine in the fruit flesh. The clear, significant differences between the genotypes will facilitate the selection of cultivars containing the largest proportion of components beneficial for human health.

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This paper presents a structural model of complex materials that are partly or entirely of cellular structure, and a new model of thermodynamics, which can be applied to the processes taking place in complex materials. Since the complex materials always contain cellular fraction, the supposition of cellular equilibrium is real. The complex materials are characterized by polyagent behaviour. Therefore, new concepts such as principal variables, redundancy, macroscopic/microscopic uncertainty are defined, moreover, the application of chemical thermodynamics is limited to micro processes only, and the free energy (F) and the free enthalpy (G) function cannot be generally applied to calculations concerning the bulk amount. Temperature as only a local intensive variable can be discussed. The first law of thermodynamics is expressed in the traditional way. The second law applied to the processes taking place both in open and in adiabatically closed systems is formulated as in words as an equation of stability, completed by the relations to first and second differential of entropy. In connection with the second law the Damköhler balance equation system, the Rabinowitsch–Mooney equation, and the application of dimensional analysis are presented. Only the apparent thermal capacities can be used for complex materials in general. The data of specific thermal capacity of complex materials in the proximity of absolute zero temperature are not sufficient for drawing conclusions on their entropy. The concept ‘shelf-life’ is essential in food science and practice, a Monte-Carlo method is presented for its calculation.

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In recent years, there have been many changes in the food market, which have greatly transformed our approach to food chain supervision. The increasing complexity of the food chain (e.g. globalization of food trade, expansion of raw materials and additives, technical advancement), the frequent changes in food consumption trends and the phenomenon of food crime belong to the most challenging issues for food chain control institutions. These factors require the re-evaluation of the role of consumers in the food chain. The overall aim of this research was to explore consumers’ risk perception and risk avoidance for a more efficient, targeted risk communication. In the survey 1003, face-to-face interviews were made using questionnaire. The statistical analysis of data was followed by the identification and characterization of 4 relevant target groups with cluster analysis method: disinterested youngsters (17.0%), conscious elders (39.4%), food adepts (27.5%), and soul of the family (16.1%). Results indicated, that the Hungarian society can be segmented regarding to food associated risk perception and avoidance. It has been also proven, that risk perception is influenced by demographic factors. Furthermore, we have also managed to conclude that efficient risk communication would require a well-aimed and focused communication strategy.

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Current study was taken up to develop probiotic chocolate using indigenous probiotic culture L. helveticus MTCC 5463. Preliminary trials included optimization of culture inoculums and physical form (freeze-dried or frozen concentrated) of addition and finally optimized product was tested for probiotic viability, texture, and organoleptic parameters at regular intervals during storage at 10±2 °C for 30 days. Probiotic chocolates prepared via incorporation of freeze dried culture (3% w/w) had acceptable organoleptic quality and had a similar behaviour as the control chocolate during storage. However, the viability of probiotic bacteria (2.42×108 CFU g–1) was achieved only up to 15 days of storage at 10±2 °C.

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Effects of the osmotic pre-treatment (OD) with sucrose or sorbitol solutions and different drying methods on the rehydration kinetics of apple cubes were studied. Samples were dried by hot air (HAD) at 70 ºC, by microwave (MWD) at 500 W, and by freeze-drying (FD). The rehydration of dried samples was performed in water at 80 ºC and at a mass ratio of sample to water of 1:100. The first order kinetic model was found to provide the best fit of the rehydration data. The pre-treatment and the drying method did not affect the rehydration kinetics, but the rehydration capacity after 12 min of rehydration was higher in the control samples than in the osmotically dehydrated ones, for all three drying methods. The rehydration rate and the rehydration capacity of the apple cubes dried by HAD, MWD, or FD were not affected by the solute used in the pre-treatment, sucrose and sorbitol.

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The purpose of this research was to monitor the changes during storage in survival of bifidobacteria in a soft-frozen ice cream supplemented with a yeast cell wall-based product claimed to contribute to the functioning of the immune system. An ice cream mix was prepared and pasteurised. After overnight aging at 4 °C, it was inoculated with Bifidobacterium animalis subsp. lactis Bb-12. Two batches of the mix were supplemented with a commercial Saccharomyces cerevisiae cell wall product at 2.0% and 4.0% (w/w), whereas a third batch was left unsupplemented and served as control. The final mixes were frozen, and the three products were stored at –13 °C for 7 days. The ice creams contained viable bifidobacteria cells at levels exceeding 106 CFU g–1 throughout the storage throughout the storage period. Although the yeast supplement decreased the loss of viability of bifidobacteria during frozen storage of ice creams, it imparted a slightly bitter off-flavour to the samples and it also negatively influenced the original white colour of the product, thereby necessitating further work to develop flavoured varieties of the Saccharomyces cell wall-containing synbiotic ice cream.

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Authors: Ildiko Bolkeny and Viktor Fuvesi

During the production of gas one of the major problems is the formation of hydrate crystals in the pipeline. The growing hydrate crystals can form hydrate plugs in the pipeline. The hydrate plug effect lengthens production outages and results in the loss of money of the maintainer, because the removal of the plug is a time consuming procedure. One of the solutions used to prevent hydrate formation is the addition of modern compositions to the gas flow. The modern compositions help to dehydrate the gas, thus, the size of hydrate crystal does not increase. The substances, used in low concentrations, have to be locally injected at the gas well sites. Thus, an injector unit is required for this purpose. The production-related aspect that the consumers expect much more flexibility from gas provider cannot be neglected because of the habits of the users and the appearance of energy-saving technologies are different. The first part of the article a newly developed injection system is introduced. To achieve optimal dosage, not only the hardware of injection system is important, but also the software. In addition to the traditional control, a preventive inhibitor dosing system can be developed, based on model driven system. The nature of the model highly influences the quality of control system. In the second part of the article a machine learning based predictive detection system is introduced

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The supply quality of a public transport system can be characterized by a few frequently alluded factors. These factors are often not fully considered in emerging countries by decision makers, generally, the decisions are made through a top-down process, while preferences of the demand side would also be essential. This paper suggests an approach aiming to get an overview of passenger’s demands in Mersin city ‘Turkey’. As methodology, analytic hierarchy process has been applied based on created questionnaires that has been used regarding the hierarchy of quality factors, and as evaluators, the public and governmental decision makers have been involved in the survey. The degree of public satisfaction about public transport has been decided by analyzing collected data.

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Asphalt paved roads prematurely exhibit a cracking pattern similar to that in the old underlying pavement. The cracking in the new overlay surface is due to the inability of the overlay to withstand shear and tensile stresses created by movements concentrated around preexisting cracks in the underlying pavement. This movement may be due to traffic loading causing differential deflections at cracks in the underlying pavement layers, expansion or contraction of subgrade soils, expansion or contraction of the pavement itself due to changes in temperature, or combinations of these phenomena. Due to heavy deformation of asphalt paved surface, using European funds, the Government of Macedonia initiated rehabilitation of Corridor X close to the Tetovo section. For the reconstruction of this important section of the motorway, an experimental programme was conducted to determine the effects of geogrid reinforcement on mitigating reflection cracking in asphalt overlays. The objective of this study is to assess the inclusion of geogrid in the pavement cross-section and the accumulation of permanent deformation. The geogrid position, type of existing pavement, temperature, and joint/crack opening were analyzed in three site trial tests. Crack propagation under repeated loading was monitored as well. The results indicate a significant reduction in the rate of crack propagation in reinforced samples compared to unreinforced samples of old asphalt pavement. The presented pavement design procedure could be tailored to the specific needs of the project and implemented in various road rehabilitation projects.

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The vast rural areas, which contain historical, cultural heritage and natural resources areas are the root for the stability of China and the foundation of the Chinese nation. However, excessive urban development and construction has affected these smaller rural villages, which were left behind due to China’s rapid economy. This is a design study of the ‘Beautiful Village’ Project, initiated by the local government, in order to demonstrate an opportunity to redesign the rural areas. This paper exhibits the experiences and impressions of the architects from China Central Academy of Fine Arts who took part in the architecture design for the villages. In order to achieve this, a series of investigation and analysis was done by the architects to reveal the present situation of the villages in China. Additionally, the active participation of the villagers is crucial in the successful re-development of the area. The main objective of this paper is to therefore identify the difficulties and problems encountered by the village and to propose a counter solution in order to design a better living condition for the rural areas of China.

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The reconstruction of military defense systems, (e.g. World War II defense lines) is generally based on military object identification and mapping. Since unexploded bombs can be still dangerous today, detecting bomb craters can be useful in creating hazard maps. The most significant problem is managing the large amount of relevant data. Therefore, there is a strong demand for automatically select the potential danger zones and also automate the entire processing workflow. Automatic methods have been developed to reduce the areas of interest. In addition, this method can be applied in other tasks as well, for example in settlement detection.

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Authors: Danilo V. Ravina, Marc Christian Y. Ruz, Rowell Ray Lim Shih and István Kistelegdi

Evacuation centers play a vital role for natural disaster-prone countries like the Philippines. In the Philippines, a public school building serves as temporary evacuation centers for the displaced families. This study presents the design and methodology of blackboard modular furniture that can be converted to an emergency partition and storage for emergency provisions. These modular partitions provide a sense of privacy for each of the affected families, which are needed in any evacuation centers, particularly on the sick, aged, menstruating women and lactating mothers, among others. By using the participative design method, the design will therefore ensure user acceptability by the stakeholders. The resulting design allows for adaptability and portability, which therefore reduce material waste and cost. The final design was the product of the both participatory design approach while following the guidelines of the Department of Education of the Philippines.

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Though problems related to physical accessibility of the built environment are quite complex, this paper chooses to discuss the case study of a Visioning Workshop for the City Park of Prizren as a model of participatory workshop with the involvement of persons with disability and the elderly. The main aim of the paper is to discuss the participatory design workshop, which objective was finding solutions for elimination of physical barriers in the park and providing programs that would increase its vitality. Participatory design workshop in this case is presented as a methodology for gathering information, establishing design criteria and programmatic requirements with the involvement of the community of persons with disability.

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This study exhibits the use of participatory design in the development of a community housing project for the twelve family members of the Donnaville Homeowners Association in Barangay 177, Caloocan City, Philippines. All families have been living as informal settlers of which portions of it were considered unsafe due to recurrent flooding during heavy rains. The housing project study was part of a workshop initiated by members of the Community Architecture Network. In order to achieve this methodology, the community architects arranged workshops between members of the families. The members were divided into teams that worked separately and then collectively identify strategies in improving the design and layout of the housing unit according to the needs of each family. The teams identified various interventions in order to effectively reduce the cost of each new unit. Finally, through comprehensive discussions and exchanges between the members, the resulting layout and schematic design of the housing unit were achieved that was desirable to the families. By using participatory design in the development of a project, in this case, a community housing unit, user acceptance is therefore increased and rejection is reduced by the stakeholders.

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The design specifications of composite trusses are only partially included in the European standards. However this construction system can be considered as one of the most economical for building and bridge structures. In general, the composite trusses can be used for greater spans up to the 30 m, which allows better use of internal space without restricting columns. They are appropriate also to meet the requirements for building height limitation, the need to run complex electrical, heating, ventilating, and communication systems. To create the interaction between steel and concrete, it is necessary to prevent the relative slip at the steel and concrete interface using the shear connectors. But the local effects of a concentrated longitudinal force and the distribution of the shear force between steel section and concrete slab, as special task, should be appropriately examined. The finite element analyses can be used to investigate numerically this structural system behavior, exploiting several computer procedures. The experimental research has tested these procedures. The outputs of this study are presented in the paper.

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Modern architecture is unimaginable without fair-faced concrete. However, there is no generally accepted method for design the suitable concrete composition to get the required surface quality. This paper presents the effect of saturation degree on fair-faced concrete surfaces and raises additional research areas with regard to the formwork geometry and packing density of aggregate. This study is the first part of a wider research that aims to work out a method for determination of the adequate saturation degree of cement paste depending on the geometrical proportions of the formwork to reach the highest surface quality.

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Authors: Miroslav Strieška and Peter Koteš

The subject of this research was influence of the environmental parameters, like temperature, humidity and pollutants, on the corrosion rate of the zinc protective coating of the steel structural elements. Zinc is usually used to protect those elements against corrosion. The idea was to study the corrosion of zinc in different parts of Slovak Republic in order to create the so-called corrosion map of the country. The corrosion rate of zinc r corr was calculated according to standard ISO 9223. Results have shown that both the input parameters, as well as the corrosion rate of zinc, are changing with time.

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Authors: Dušan Rusnák, Štefan Stanko and Mária Trošanová

Assessments of sewer systems are key tools in verification of sewer hydraulic capacity. Rain sewers and combined sewers are most susceptible regarding system overload and so while assessing them; proper choice of design rainfall is inevitable. The calculation of design rainfall is time-consuming and inefficient and that was the reason that leads to development of design rainfall analysis tool in order to minimize the length of the calculation process of design rainfall. The tool incorporates calculation of design rainfall depending on the specified area of interest within Slovakia and chosen periodicity, allows block rain, reduced block rain and synthetic rain to be calculated with the possibility of their mutual comparison, and also serves to generate background data for further use in form of portable document format and excel files.

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Aerobic wastewater treatment requires extensive aeration, which primary function is to provide oxygen to the biomass responsible for degradation of wastewater constituents. Besides the effective oxygen transfer efficiency aeration is responsible for fluid flow created by bubbles. In this research bubbles were released from plate diffusers and the impact on mixing were analyzed. Various aeration flow rates and initial bubble sizes were calculated. Residence time distributions in each scenario were compared applying numerical tracer study. Outcome of the calculations is that the aeration reduces the theoretical residence time significantly and therefore the traditional sizing methods needs to be revisit in wastewater treatment.

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In this paper the authors partially summarize the results of a research on glued insulated rail joints with fiber-glass reinforced plastic fishplates (brand: Apatech) related to own executed laboratory tests. The goal of the research is to investigate the application of this new type of glued insulated rail joint where the fishplates are manufactured at high pressure, regulated temperature, glass-fiber reinforced polymer composite plastic material. The usage of this kind of glued insulated rail joints is able to eliminate the electric fishplate circuit and early fatigue deflection and it can ensure the isolation of rails’ ends from each other by aspect of electric conductivity.

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The paper discusses the standard of the Epstein frame that has been used to measure magnetic characteristics of the core made of material M250-35A supplied by different frequencies between 1-400 Hz. The measuring program has been built in LabVIEW including a control, filter and data save section as well. COMSOL Multiphysics 4.3b has been chosen as simulation environment, in which the Jiles-Atherton hysteresis model has been implemented.

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The following article presents a new method for the qualitative and quantitative detection of hydrophobing injection media used as a subsequent masonry-seal against rising damp. Within the scope of this detection method, condensation processes are carried out on the sampling material in the environmental scanning electron microscope with determination of the hydrophobic properties.

With this new method statements can be made about the actual sealing quality in the injection level compared to untreated masonry areas. The method can be applied to all capillary masonry treated with a subsequent hydrophobic injection.

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A comprehensive analysis of the finite element method based lamination modeling has been performed and the results are presented in this paper. The simulations are made in two subsequent steps. In the first step, the approximate magnetic field distribution inside the material with linear characteristics is determined assuming a bulk material having anisotropic conductivity and laminates are not taken into account. In the second step, the eddy current field inside the individual laminates is modeled. The boundary conditions of any individual sheets are obtained from the bulk model. The paper presents the advantages and the drawbacks of the applicable potential formulations. Results are compared with the quasi-static electromagnetic field obtained from a reference solution taking account of each laminate.

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Authors: Richard Honti, Ján Erdélyi and Alojz Kopáčik

Recently, attempts have been made to automate data acquisition, which is also related to efforts to automate data processing. The paper deals with the automation of terrestrial laser scanning data processing. The approaches for point cloud segmentation are briefly described. An algorithm based on random sample consensus is proposed for automated plane identification and plane segmentation from point clouds. The proposed approach was tested by processing point clouds; the results of the testing are also described. Based on the proposed algorithm, a standalone application for automated plane segmentation from laser scanner data using Matlab® software was developed.

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In the present study, fully developed laminar flow with forced convection heat transfer of Al2O3/water and TiO2/water nanofluids inside a vertical tube subjected by constant heat flux from the wall was numerically analyzed using Ansys Fluent release 17.2. In this work, the single-phase model was proposed to simulate the water and nanofluids heat transfer characteristics; spherical nanoparticles with a constant diameter equal to 30 nm are used. The study has been carried out on a Reynolds number with ranges (400-2000) and nanoparticles volume concentration up to 1.5%. the results show that the average Nusselt number for nanofluid is higher than that the base fluid (water) especially for TiO2/water nanofluid, the Nusselt number increased with increasing Reynolds number and volume concentration in all cases. The enhancement ratio for nanofluids compared to water at different volume friction was studied; the higher improvement is about 3.51% for TiO2/water nanofluid with 1.5% volume fraction. Moreover, a study for pressure drop along vertical tube was discussed.

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Authors: Mária Trošanová, Ivona Škultétyová and Dušan Rusnák

Reverse logistics is one of the main processes for the realization of the circular economy. The aim is ensuring the material recovery of waste through its re-use or recycling in a way that is environmentally friendly and economically interesting. The municipality is responsible for the waste management of municipal waste streams. This paper deals with an efficiency of municipal expenditures dedicated to waste management from the expenditures allocated for environmental protection and the achievement of waste management objectives.

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The paper presents partial results of research and develops of innovative board with built-in infrared heating film. The base of technical solution of innovative board is enclosed by the infrared heating film between two construction boards. The paper presents partial outputs related to the research of the innovative board efficiency in relation to surface temperature. The methodology for measuring the surface temperature of the board was determined as a part of the board initial research. Surface temperature sensors were used for measurement. Time required to achieve the reference surface temperature of the board was investigated after switching on the heating film. The results of partial measurements offer the basis for further analysis and research of the innovative board.

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Energy efficiency and reduction of a building’s environmental impact are the major priorities of the energy and environmental policy worldwide. The passive strategy is one of the most effective strategies for energy efficiency and thermal comfort either in newly built or in retrofitting existing buildings. This study investigated energy and comfort optimization in a typical traditional house in Sulaimani city in Iraq, through analyzing, investigating, and improving energy efficiency using passive strategies. Several strategies for improvement were investigated, including window-to-wall ratio, thermal insulation, infiltration, natural ventilation, shading, and form compact. The total convenient passive strategies for the residential building typology was summarized and proposed as an optimal solution model in terms of energy efficiency and thermal comfort. An optimization model was presented and the results were compared with the reference model. The results revealed that the optimum model performed better 34% than the existing traditional model in term of energy consumption.

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The aim of this paper is to review and emphasize the development of using the comprehensive guidelines for the latest restoration of cultural heritage buildings, in this particular case the Jashar Pasha Mosque in Prishtina, Kosovo. The importance of using specific guidelines for the restoration plans will encourage all responsible bodies to think more in a structural way as far as historical sites and architectural heritage is concerned. This includes the need to assess more profoundly the necessity of using restoration and conservation guidelines towards more successful management of projects of this nature, ensuring the effective and efficient safeguarding of cultural heritage in Kosovo, in general.

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In our publication, more than one basic toothed gear pairs have been designed and modelled. Normal tension dispersions – appearing in the contact zone of the drive pair – and their measure on contact tooth surfaces have been analyzed by the effect of a given moment load. During designing the numbers of the teeth of the gear pairs have been chosen equal, but the modules of the pairs have been different. We analyze how normal tension values form on the tooth surfaces of the gears in the contact zone of the tooth and on their root zone as a function of the change of the module in the case of the same meshing method, loads and boundary conditions.

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This research article is focusing on the optimization of different welding process parameters which affect the weldability of stainless steel (AISI) 304H, Taguchi technique was used to optimize the welding parameters and the fracture mode characterization was studied. A number of experiments have been conducted. L9 orthogonal array (OA) (3×3) was applied. Analysis of variance ( ANOVA) and signal to noise ratio (SNR) was applied to determine the effect of different welding parameters such as welding current, wire feed speed and gas flow rate on mechanical, microstructure properties of SS304H. Ultimate tensile strength (UTS), toughness, microhardness (VHN), and mode of fracture was examined to determine weldability of AISI 304H and it was observed from results that welding voltage has major impact whereas gas flow rate has minor impact on ultimate tensile strength of the welded joints. Optimum process parameters were found to be 23 V, 350 IPM travel speed of wire and 15 l/min gas flow rate for tensile strength and mode of fracture was ductile fracture for tensile test specimen.

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Modern food industry widely uses a variety of flavour and fragrance materials. One of the most used compound groups is the aldehydes. The benzaldehyde, also known as artificial almond oil, is one of the most commonly used flavouring in food industry nowadays. The effects of this compound on different species are well known, a lot of toxicological information can be found in the literature. 4-ethylbenzaldehyde is also a member of aldehyde group, the physical properties are similar to benzaldehyde and also has almond scent. Unlike benzaldehyde, it has no chemical safety assessment according to its chemical safety sheet, and only one experiment can be found on its effects on vertebrates. This compound can also be found at the group of flavours and fragrances. The aim of this study was to examine the subacute DNA and tissue damaging effects of EBA. The genotoxic effects of EBA in zebrafish were evaluated by using micronucleus assay. Significant increase in the micronucleus frequency had been described for all tested concentrations. Alterations were found in the liver of the fish group treated with 11 mg l–1 EBA for 21 days.

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The effect of short-term higher ambient temperature (HT) and continuous vibration (CV) treatment was comparatively characterized by sensory evaluation and chemical analysis. Results of quantitative descriptive analysis of modified frequency (MF) showed that HT causes both in red wine and white wine a decrease of fruity and floral characters, an unbalance of taste, and a shortness of aftertaste length. CV wine showed very close sensory characters to control in most terms evaluated. Seventy-four volatile compounds were quantitative analysed by solid phase microextractiongas chromatography-mass spectrometry, and the principal component analysis (PCA) was conducted on the 23 volatiles of highest odour activity value (OAV). The concentrations of potential fruity and floral aroma attributors like isoamyl acetate, ethyl butanoate, ethyl 2-methylbutanoate, ethyl hexanoate, ethyl octanoate, β-damascenone, and linalool were lower in HT wine than that in original wine and CV wine.

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Authors: T. Tóth, J. Kovarovič, J. Bystrická, A. Vollmannová, J. Musilová and M. Lenková

Wild garlic (Allium ursinum L.) is a wildly growing plant that grows in forests and next to the streams. It has a specific aroma and taste resembling garlic. Wild garlic is increasingly favoured in gastronomy, food industry, and modern food technologies. The aim of this study was to analyse the dynamics of changes in total polyphenols content (TPC) and antioxidant activity (AOA) in wild garlic leaves and flowers during the vegetation period (from April to June). The samples of plant material were collected from the area of Bratislava – Železná studienka. The samples of fresh leaves and flowers were homogenized and a methanolic extract was prepared. These extracts were used for analyses. Total polyphenol content in the samples ranged from 726±10 mg GAE/kg FW to 14.1×102±13 mg GAE/kg FW. The values of antioxidant activity were from 10.7±1.57 to 25.9±1.06% inhibition FW.

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Refined olive oil (ROO) was blended with tristearin (TS) and palm oil (PO) at two different ratios (ROO:TS:PO; 75:15:10 and 85:10:5) and chemical interesterification was performed in order to produce two interesterified fats (IF1 and IF2) with high unsaturated fatty acids and low trans fatty acids contents.

Solid fat content (SFC), slip melting point (SMP), and fatty acid composition were determined in IF1 and IF2; the values were compared to that of partially hydrogenated industrial cookie shortening (ICS). Higher SMP was measured in interesterified fats contaning 75% ROO (IF1) and lower SMP was obtained in interesterified fats containing 85% ROO (IF2). SFC values of interesterified ROO blended oils were lower than ICS. Interesterified fats were used for cookie production, and cookie quality parameters, including oxidation stability, were determined.

Results showed that hardness values of cookies were not affected by fat types and higher spread ratios and lighter colors were obtained. IF1 and IF2 had higher total oxidation values as compared to ICS.

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Authors: K.G. Mladenović, M.Ž. Muruzović, O.D. Stefanović, T.D. Žugić Petrović and Lj.R. Čomić

The antibacterial activity of potassium metabisulphite, potassium benzoate, potassium propionate, and potassium nitrate were evaluated against 15 species of bacteria using diffusion and microdilution methods. Potassium metabisulphite showed the greatest activity (MIC varied in the range of 0.78 mg ml–1 to 3.12 mg ml–1), then potassium benzoate (6.25 mg ml–1 to 12.5 mg ml–1) followed by potassium propionate and potassium nitrate (6.25 mg ml–1 to 100 mg ml–1). Effects of potassium benzoate, potassium propionate, and potassium nitrate on the sugar fermentation, the effect of potassium benzoate on cell membrane permeability and on amylolytic activity of bacteria were tested. The results indicated inhibition of fermentation, loss of intracellular macromolecules (proteins) from treated cells, and inhibition of amylolytic activity.

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The statistical data show that the application of active cooling is spread widely in residential and commercial buildings. In these buildings, the ventilation is significantly increased in the whole energy consumption. There are similar problems in the operation of post-insulation of existing buildings. In this case, the energy consumption of the ventilation system gives a major proportion of the whole building services energy consumption. The opportuneness of this research shows that the actual available calculation procedures and technical designing data are only rough approximations for analyzing the energy consumption of air handling units and the energy saved by the integrated heat or energy recovery units. There are not exact methods and unequivocal technical data. In previous researches, the production and development companies have not investigated the effectiveness of the energy recovery units under difference ambient air conditions and the period of defrost cycle when the heat recovery can only partly operate under difference ambient air temperatures. During this term, a re-heater has to fully heat up the ambient cold air to the temperature of supplied air and generate the required heating demand to provide the necessary indoor air temperature.

Open access
Authors: S. Vannini, R. Pagiotti, M. Acito, S. Levorato, L. Dominici, C. Fatigoni, V. Gianfredi, M. Moretti and M. Villarini

The alkenylbenzene estragole (systematic name, 1-allyl-4-methoxybenzene) is a natural component of essential oils from various spices and herbs, including fennel, and it is used as a food and beverage flavouring agent. Estragole has been reported to be hepatocarcinogenic at high doses in rodents. However, in a previous in vitro study, we found that estragole did not exhibit cytotoxic effects after 4 hours of exposure, nor did it induce DNA damage or apoptosis in human HepG2 hepatoblastoma cells. As fennel tea is widely used for symptomatic treatment of spasmodic gastrointestinal conditions in infants, we aimed at further assessing its safety in a different experimental setting. We thus searched for possible cytogenetic effects and interference with cell-cycle progression in the same human hepatoblastoma cell line. Estragole did not show any clastogenic/aneugenic activities in the cytokinesis-block micronucleus assay, and no effects on cell-cycle checkpoints were observed.

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Authors: A. Lončarić, A. Pichler, N. Rašić, I. Vukoja, A. Leventić and M. Kopjar

Nowadays, people are focusing on antioxidant-rich food due to its beneficial effect on health. Thus, the goal of this study was to investigate the interactions between catechin, quercetin, and gallic acid in the presence of sugars (sucrose and trehalose) in complex food matrix such as pomegranate juice. Antioxidant activity (AOA) was measured by three different methods, DPPH and ABTS radical scavenging activity and ferric reducing antioxidant power (FRAP). In this paper, fundamental differences among used AOA measuring methods were confirmed, which can be traced back to interactions occurring between phenols and/or sugars. Even though addition of individual phenols increased AOA of mixtures, in the majority of binary and ternary mixtures antagonistic effects were observed. Positive effect of sugar addition was more pronounced in binary mixtures but the results were highly dependent on used AOA method.

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Constructing a new building or any other civil engineering project from scratch is a challenge for the construction industry as novelty designs may be produced by designers but they are often constructed by low skilled labor on site. The unique and sometimes complex nature of the construction sector arises because a large number of different professional groups have different interests and requirements, which often conflict with one another. In principle, each construction company aims to construct a project without any defects from the very first activity on site right up to final completion. This aim is almost impossible to achieve throughout the entire construction duration because of many factors, including: low skilled labor, difficult site conditions, and incomplete designs, varying quality cultures in each company, poor communication and poor management. Therefore, construction defects are things which we can assume to have occurred on the site. Defects occurring during the construction process are sometimes costly and preventable mistakes. Research has shown that correcting defective components that are identified late in the construction process or during the maintenance period accounts for approximately 15% of the total construction costs. This paper presents a case study of the defects that occurred during a motorway construction project as a consequence of poor workmanship by an untrained workforce and it aims to raise awareness of the need for on-the-job training for quality managers in order to minimize defective works and reduce the project costs spent on correcting them. It also identifies the various factors that cause construction defects and suggests measures that can be taken to reduce them.

Open access

The current work reports the ochratoxin A (OTA) levels in 23 food (bread, dried fruit, pulse) and beverage (black tea, coffee) products commonly consumed in Turkey determined with ELISA. OTA levels in kidney bean, haricot bean, and red lentil samples from Turkey were investigated for the first time in this study. The highest OTA levels were detected in instant coffee (158.9 μg kg–1), black tea (139.5 μg kg–1), and filter coffee (118.4 μg kg–1) samples. Of the tested samples, 78.27% exceeded legal limits of OTA. These results support the existing knowledge that food and beverages should be regularly and effectively controlled to protect human health.

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Optimization of extraction ratio (ER) of tree peony seed protein (TPSP) was investigated using response surface methodology (RSM). The second-degree equation for ER of TPSP had high coeffi cient (0.9625) of determination. The probability (P) value of regression model signifi cance was less than 0.001 by analysis of central composite rotatable design. Relationships of ER to pH, liquid/solid ratio, squares of all factors, and cross-product factors (x2x3, x2x4, x3x4) were signifi cant (P<0.05). Whereas, extraction time, temperature, and cross-product terms (x1x2, x1x3, x1x4) were not signifi cant factors (P>0.05). Optimum extraction conditions were 3.42 h, pH 9.50, 50.80 ºC, and 9.54 ml g–1 of liquid/solid ratio with the maximum ER (43.60%) . SDS-PAGE indicated TPSP had mainly four proteins (180, 100, 60, and 35 kDa) with four subunits of 60, 48, 38, and 23 kDa. TPSP had a good amino acid composition with abundant essential amino acids (39.76%) determined by amino acid analysis.

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Authors: M. Zheng, L. Zhang, H. P. Teng, J. Hu and M. L. Hu

In the present paper, CFD simulation is used to perform the numerical calculation of behaviours of multi-blade drag typed VAWT. The sliding grid technology, FLUENT software and PISO algorithm are involved. By taking wind power efficiency C p as the goal function, the optimal situations of multi-blade drag typed VAWT with 4 and 6 blades are conducted by CFD simulation. In this investigation, the variable parameters include the rotation rate of wind-mill ω, the blade installation angle θ and the blade width d. The results show that: the optimal working conditions for the 4-blade wind mill at the inlet wind speed 8 m/s are ω = 18 r/ min, θ = 28°, and d = 0.83 m, which induces an optimal wind power efficiency rate C p = 27.127%; the optimal working conditions for the 6-blade wind mill at the inlet wind speed 8 m/s are ω = 18 r/min, θ = 27°, and d = 0.67 m, which leads to an optimal wind power efficiency rate C p = 30.404%.

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Gastrodia elata Blume polysaccharide (GEP) was extracted and then chemically characterised. Its antioxidant activity was evaluated in vitro and in vivo. The results of the in vitro investigation show that GEP consists of glucose with molecular weight of 875 185 Da and exhibits high hydroxyl radical scavenging, as well as 2,2-diphenyl-1- picrylhydrazyl activity and reducing capacity. For antioxidant activity in vivo, D-galactose-induced-aged mice were orally administered with three different doses of GEP over a period of 6 weeks. The administration of GEP dosedependently increased the body weight gain rates, liver and brain indices, superoxide dismutase and glutathione peroxidase activities, and malondialdehyde levels in the sera and brains of ageing mice. These results suggest that GEP exhibits high antioxidant activity and can retard human ageing associated with free radicals.

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When renovating an existing building, keeping the original window and installing added convex window is beneficial for the reduction of heating energy demand. This solution is free of the disposal and/or recycling of demolition waste. In the summer season as far as the transparent structures of the building are concerned, in general, heat protection has to be used. In the case of the added convex window, it can be provided by the external air curtain mode; the movable shading device is in the buffer zone. This is a well-protected place for it, so that it can be as simple and cheap as an inner shading device. In this article examinations of the efficiency of the external air curtain mode for the heat protection is presented. The summer overheating has been analysed in two experimental huts. It has been proven that simple shading device in added convex window tempers the summer overheating as efficiently as the combination of usual window and external shading device (which is exposed to heavy weather effects and is difficult to maintain).

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Intramuscular connective tissue plays an important role in determining meat tenderness. The objective of the research was to compare the collagen/hydroxyproline content and X-ray Computed Tomographic (CT) connective tissue proportion of longissimus thoracis (LT) muscle in Hungarian Simmental bulls and cows. Animals (n=24) were slaughtered at similar live weight (bulls: 530.6+44.7 kg, cows: 527.3+53.5 kg) under standard commercial conditions in Hungary. After 24 h chilling, LT samples were taken from the right half carcass at the 12th rib. CT examinations were carried out with a 16-slice CT system (slice thickness: 5 mm). Samples were scanned at different user-selectable tube voltages e.g. low: 80 kV and high: 140 kV. CT value at LT muscle area of each mixed scan (80 and 140 kV) was determined. Volumetric connective tissue content was measured (above 200 CT value) as well. Following CT, the hydroxyproline/collagen content and intramuscular fat content of LT were determined. Cows had lower carcass weight (247 kg vs 295 kg), EU conformation score (3.5 vs 5.5), and fatness score (4.2 vs 5.9) than bulls (P<0.01). Bulls had higher LT area, but intramuscular fat content was similar for bulls (2.8±1.9) and cows (2.7±2.0). On the other hand, bulls had lower CT intramuscular connective tissue proportion in LT compared to cows (0.4±0.2% vs 0.7±0.3% P<0.01). The same tendency could be observed for the collagen content (0.5±0.2% vs 0.7±0.1% P<0.01). Correlation between the CT connective tissue proportion of LT and collagen content was r=0.8 (P=0.000). There was a weak positive correlation between slaughter age and CT connective tissue as well as collagen content of LT (r=0.3–0.4, P<0.05). In conclusion, intramuscular connective tissue proportion in LT increased with slaughter age, and older cows had higher collagen and connective tissue proportion than bulls. Mixed CT scans can be used for the analysis of intramuscular connective tissue content.

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Authors: J. Montiel-Ventura, J.J. Luna-Guevara, M.A. Tornero-Campante, A. Delgado-Alvarado and M.L. Luna-Guevara

The aim was to examine conditions of convective drying and spray-drying to improve preservation of lycopene content in tomatoes. The weight, size, colour, pH and °Brix values were evaluated in fresh fruit (FF) and colour (L, a, b), hue, and chrome indices were analysed from dried tomatoes, too. Tomato paste was dried (40, 50, 60, and 80 °C with times of 540, 390, 270, and 240 min) under convection conditions and pulverized. In the encapsulation treatments core material with tomato powders of 50, 60, and 70%, shell solution of maltodextrin/gum arabic 1:1, flow rate of 4, 6, 9, and 12 ml min–1, and inlet air T of 160, 170, and 180 °C were used. The physicochemical properties of FF corresponded to a degree of ripeness for consumption. The a, a/b, and hue values of dried tomatoes at 50 °C significantly correlated to red colouring and higher lycopene content (47.98±1.49 mg/100 g). The encapsulation with 50% and 60% of tomato powders, 170 °C and 9 ml min–1 treatments increased lycopene contents to 10.41 mg/100 g, 10.20 mg/100 g, and 11.51 mg/100 g, respectively. The results demonstrated that the physicochemical and functional properties were influenced by drying conditions, providing useful information for increasing the stability of lycopene in dried tomatoes.

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Authors: T. Prokopov, A. Slavov, N. Petkova, V. Yanakieva, B. Bozadzhiev and D. Taneva

The development of food products that contain value-added dietary fibre beside different classes of phytochemicals is of great interest nowadays. The present research aimed to evaluate the powder obtained from onion processing waste (OPW) for its potential use as a value-added by-product in food sector. Data on chemical and microbiological characterization of onion processing waste powder (OPWP) were obtained. The dietary fibre content and antioxidant activity were also determined. The results showed that the OPWP was a low-calorie natural source of insoluble fibres (60.52±0.13 g/100 g dw), total phenols (41.04±1.22 mg GAE/g dw), and total flavonoids (20.44±1.22 mg QE/g dw). Moreover, the OPWP could be considered as an important source of total fructans (9.04±0.28 g/100 g dw), fructooligosaccharides (2.76 g/100 g dw), and inulin (2.41±0.18 g/100 g dw). In conclusion, this OPWP could be used as a value-added and healthy food ingredient.

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Polytetrafluoroethylene surface was treated by atmospheric DBD plasma for 1 min in ambient conditions. The effect of DBD plasma introduces signifi cant increasing of the surface energy (wettability) within 24 hours after treatment. However, the surface starts recovering to the original state with ageing. The surface elemental composition shows enhancing in oxygen content which suggests presenting the polar functional groups. The surface roughness exhibits a mild reduction within 24 hours after treatment. Whereas, the roughness values start to increase with the function of time.

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Increasing building energy performance has become an obligatory objective in many countries. Thermal bridge is a major cause of poor energy performance, durability, and indoor air quality of buildings. This paper starts with a review of thermal bridges and their negative impacts on building energy efficiency. Based on published literatures, various types of building thermal bridges are discussed in this paper, including the most effective solutions to diminish their impacts. In addition, various numerical and experimental studies on the balcony thermal bridge are explored. Results show that among all types of thermal bridges, the exposed balcony slab produces the most challenging thermal bridging problem where an integrated thermal and structural design is required. Using low thermal conductivity materials in building construction could help in reducing the impact of thermal bridges. Finally, further investigations are needed to develop more innovative and effective solutions for the balcony thermal bridge.

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It is a prime aim to ensure a suitable comfort level in case of office buildings. The productivity of office employees is directly influenced by the comfort. Thermal discomfort and poor indoor air quality deteriorate the intensity and quality of human work. We investigated the comfort in office buildings with on-site measurements during the summer season. The office buildings were operating with different HVAC (Heating, Ventilating and Air-Conditioning) systems: ducted fan-coil with suspended ceiling, installation, non-ducted fan-coil with floor-mounted installation, active chilled beam with fresh air supply.

We evaluated the thermal comfort under PMV (Predicted Mean Vote), PPD (Predicted Percentage of Dissatisfied), the local discomfort based on DR (Draught Rate) and the IAQ (Indoor Air Quality) based on carbon dioxide concentration. The comfort measurements were evaluated. The measurements were evaluated with scientific research methods, comfort categories based on the requirements of CR 1752. The results of this comparison were presented in this article.

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One of the easiest ways to integrate renewable sources of energy into the heat producing system of a building is the application of transpired solar collectors. They are widespread in North America, where air heating is a common heating alternative, but they are gaining bigger share in the European solar thermal market nowadays. Their simple construction, maintenance-free operation and high working efficiency result in low capital and operating costs. The combination of TSC with other system elements results in additional benefits. Preheating the combustion air of large-scale boilers results in the increase of boiler efficiency and thus the reduction of natural gas consumption and CO2 emission. Whether to choose TSC or heat recovery unit for a certain air conditioning system has to be investigated by examining efficiency-influencing factors of both systems. Besides solar air heating, transpired solar air collectors can reduce the cooling demand on a building. Roof ventilation and nocturnal radiant cooling are two alternatives, which are being presented in the current paper.

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β-Galactosidase is an enzyme of commercial importance owing to its multiple benefits. Among all microbial sources, fungal species are of great interest for the production of this enzyme. Thus, the aim of this present work was to optimize the media as well as process parameters to achieve maximum β-Galactosidase production by solid state fermentation using the fungal isolate Rhizomucor pusillus. Various agro-industrial residues were tested for carbon as well as for nitrogen sources. The different process parameters were also studied to observe their effects on β-galactosidase production. Among all screened agro-industrial residues, wheat bran and corn steep liquor had the potential to be used as carbon and nitrogen sources, respectively; whereas MgSO4 was found to be a suitable salt supplement. The optimal process parameters included particle size of 1000 microns, 50% moisture content, pH 5.5, 50 ºC temperature, and 7 days of fermentation.

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Intramuscular fat content (marbling) is an economically important factor in many beef carcass classification systems. The aim of this study was to evaluate marbling of longissimus muscle with different methods (USDA marbling score, image analysis of X-ray computed tomography scans, and conventional method), moreover it was aimed to establish the relationship between marbling traits and SEUROP conformation and fat score. Bulls (n=46) were slaughtered at an average weight of 536±126 kg and an average age of 646±437 days. The average growth rate of bulls was 955 g day–1, the average chemical fat content of longissimus varied between 2.3 to 5.0% in fat classes. The intramuscular fat content on CT-scans closely correlated with chemical fat content (r=0.9). The highest frequency of USDA marbling score was “small” (55.2%), followed by “slight” (25.5%), “modest” (17%), and “moderate” (2.1%). Bulls with higher growth rate had lower CT-measured marbling traits in longissimus muscle (r = –0.4 – –0.5). The CT scans of longissimus muscle can be used for the evaluation of marbling in Hungarian Simmental cattle. The SEUROP conformation and fat score have no relationship with marbling traits.

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This study aims at revealing the power of architectural representation through drawing on community engagement and development during the design process. Considering the drawings as a medium for obtaining knowledge and using them as a means of communication, for the generation and development of designs together with the community, the idea behind was to understand if the representation and communication approach can trigger the community participation, engagement and education on understanding and creating their future city.

For the accomplishment of this research the mixed methodology was used, quantitative methods with tools such as questionnaires and mental maps, whilst qualitative method employed interviews, empirical studies and observation on the ground.

The use of a certain architectural representation as a communication means, that could be attractive and well understood by the community, can encourage public engagement, discussion and generation of ideas, by this ensuring their collaboration during the planning and design process, as active participants and well-informed citizens.

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The generation of printable shellcode is an important computer security research area. The original idea of the printable shellcode generation was to write a binary, executable code in a way that the generated byte code contains only bytes that are represented by the English letters, numbers and punctuation characters. In this way unfortunately only a limited number of CPU instructions can be used. In the originally published paper a small decoder is written with instructions represented by printable characters and the shellcode is decoded on the stack to be executed later. This paper, however describes a proof of concept project, which converts the source code of a full assembly program or shellcode to a new source code, whose compiled binary code contains only printable characters. The paper also presents new, printable character implementation of some CPU instructions.

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One of the most important challenges in urban design is planning an appropriate street network, satisfying the demand of users with different transport modes. Understanding the nature of road networks has been thoroughly studied problem for many years and extensive professional literature is now available in this respect. In this study, five different micro-districts and their road networks have been analyzed in Budapest. Therefore, this paper is aimed at providing a contribution to the knowledge of comparing road networks of different residential estates under different traffic loads. Moreover, significant similarities and differences were identified among urban street layouts in this paper.

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The paper shows a general introduction about the connection of cities, particularly Siófok, the ‘capital’ of Lake Balaton and water surfaces through three topics: the first part deals with the past and present of waterfronts, by exploring the most important principles in their design, then describes the significant tools and methods of the Hungarian cities around Lake Balaton, the most important water surface of Hungary, related to the areas adjacent to the water. Finally, it reveals a complex design work by the authors for refurbishing the waterfront in Siófok, based on a national competition.

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Passenger car unit is an important comparison factor that helps the traffic engineer to describe the impact of heterogeneous traffic flows on the traffic performance of the infrastructure elements, compared to homogenous passenger car flows. The purpose of this study is to determine the passenger car unit value of certain vehicle types (e.g. buses, trucks) in signalized circular intersections. The values defined by the Hungarian standards are based on the weight and type of the vehicles, so it is important to know how these parameters of the vehicles influence the traffic conditions at this unique type of road junction, to be able to conduct a correct capacity calculation. PTV Vissim microscopic simulation program was used to model different traffic volumes and compositions getting by the recommended passenger car unit values for the application, and a proposal for further studies in subject.

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Avoiding the formation of shrinkage cracks is one of the most important tasks in construction of concrete industrial floors. Cracks appear on the surface of floors when the nonlinear processes in the structure lead to internal stresses that exceed the actual tensile strength of the concrete. The tensile stresses developed depend on the constrained deformation of the floor during shrinkage and the elastic modulus of the material of the concrete slab. However, on the top surface of the floor, the tensile stresses can be increased, if the shrinkage deformations are constrained by the uneven evaporation and the generated friction between the sub-base and the floor. The value of friction coefficient is depended primarily on the surface roughness of the subbase and the type of polyethylene foil used between the sub-base and the concrete slab. The paper presents the results of experimental investigations on the friction coefficient and the effects of its value on the cracking process of industrial concrete floor slabs.