Browse

You are looking at 201 - 300 of 2,613 items

Authors: Chu Xiaohui, Ganjali Bonjar Mohammad Reza, Gantumur Tsovoodavaa, Rowell Ray Lim Shih and Balint Baranyai

Along with its rapid growth in economy, the protection of heritage buildings has recently gained importance and awareness in China. This paper investigates the energy performance of a heritage building (Wang’s House) in Shanghai, as well as the thermal comfort of the users, using dynamic thermal simulations. The analysis showed that heating accounts as the highest energy demand, followed by cooling and lighting. The resulting study will help the authors to identify various sustainable strategies to improve users comfort as well as reduce the energy demand of heritage buildings in China.

Open access

Iron corrosion products of the steel canister in the nuclear waste container are highly silica sorptive materials and very much expected to delay formation of the protective layer (gel) on the nuclear glass interface. This study is focusing on the role of the iron carbonates (ankerite), which is probably one of iron corrosion products and already exists in the clay structure of the disposal depth. French SON68 inactive reference glass (alternative to the R7T7- type) samples are planned to leach in different series of experimental models with dissimilar quantities of natural ankerite. All batch experiments will be cultivated in synthetic Callovo-Oxfordian groundwater; where different pH (4-9) values and temperatures (35, 50, 90 °C) are considered. In this paper the state of the art of the radioactive waste glass corrosion in the circumstances of deep geological disposal were extensively studied.

Open access

Residential sector represents the largest energy consumer in the city of Pristina, as a capital of Republic of Kosovo. This is also the most diverse sector in terms of the energy sources used for space heating. Detailed analysis of different heating energy sources is pivotal for understanding the current situation as well as for any future systematic action in this field. In general, the main energy sources used for heating are known but the determination of their share still remains a challenge.

Main focus of the current research is to identify the key heating energy sources, to analyze their share in different zones of Pristina, and to present the heated versus living area per different energy sources within dwellings.

Data gathered in the field and presented in this paper are considered to be a first step in comprehensive analysis of the residential sector energy consumption in Pristina.

Open access

In recent years, surfaces of plaster facades increasingly have been covered with algae. This effect is reinforced by improved thermal insulation of the building.

Envelope e.g. due to the use of plastics, as well as the climate change and lower air pollution. The accumulation of condensation water is therefore of decisive importance.

So far, the amount of condensation water was determined with static weight methods. New developments in material research attempt to illustrate the susceptibility to condensation with different measurement methods. The differences can be seen in various systems and materials. Developing a model representation for the future planning of facades is thus possible for new and the existing building. This model can be used to derive new characteristics for new facade design.

Open access

Additional horizontal sealing in mineral building materials often produce insufficient or varying results despite the application of the injection agent being carried out according to the manufacturers’ specifications.

There is no current scientific explanation for this effect, which prompted this research. The main idea was to solve the question of whether the increasing filling of the capillary pores of mineral building materials with water (and therefore the degree of moisture penetration) can be connected to the varying spread of the injection agent.

After developing a test procedure, different degrees of moisture penetration were applied to samples of bricks and mortar cubes and hydrophobic injection agents were applied to the test specimens. The results showed that the degree of spreading of the injection agent was inversely proportional to the degree of moisture penetration. Consequently there is a dependence of the above mentioned parameters (the existing degree of moisture penetration and the spreading of the injection agent) and a model was developed of the spread of injection agents dependent on the existing degree of moisture penetration in building materials.

Open access

The aim of the paper is to point out the inevitability of the proof-load tests for the real and correct behavior of bridge structures in ultimate limit state and maximum allowable deformations in serviceability limit states. It is needed to point to the most consequences of resistance, reliability, durability and lifetime of the bridge structures. Using the proof-load tests for new bridges is prescribed by the Slovak standard STN 73 6209.

Restricted access

Task of shipping operations control of the Gabčíkovo Project is to synchronize several requirements. These come from versatility of GAP and must meet with the following goals. The operation of GAP must be effective (maximization of the ship locks capacity, maximization of income from electricity production in hydropower plant); reliability of operation of the ship locks must not be limited or endangered by defects on technology parts of the ship locks caused by illegal parameters of water flow in the filling and emptying system; and shipping safety must not be endangered or limited by unsuitable parameters of river way (navigable depth below minimal shipping depths in ford sections caused by flow changes on Gabčíkovo Project and ships crushing into riverbed of the Danube river).

By taking these goals into account, it is possible, in general, to define operation of Gabčíkovo Project as complex multi-criteria optimization task with many technological, water management, energetic and environmental constrains. Standard approach in solving this problem includes elaboration of optimization or simulation model of Gabčíkovo Project operation. If mathematical description of problem does not exist, ‘classic’ expert control system management must be applied. Based on above stated criteria, most effective approach to this problem appears to be creating software application that combines both approaches.

In this case, expert control system of shipping operation on Gabčíkovo Project will be software application to model hydraulic links and hydraulic regimes (discharges, water levels and flow velocities) based on relevant inputs on the ship locks and whole section of the Danube river, that is affected by Gabčíkovo Project operation.

The paper describes possible optimization solution for achieving above mentioned goals. Architecture of proposed expert control system is described in the paper and the focus is mainly on analyzing suitability of heuristic optimization methods for solving above the stated optimization problems.

Restricted access
Authors: Dávid Nagy, Laszló Aszalós and Tamás Mihálydeák

Correlation clustering is a widely used technique in data mining. The clusters contain objects, which are typically similar to each other and different from objects from other groups. It can be an interesting task to find the member, which is the most similar to the others for each group. These objects can be called representatives. In this paper, a possible way to find these representatives are shown and software to test the method is also provided.

Open access

The pressing of equal channel angular pressing - parallel channel process has an effect on microstructure and mechanical properties of the composite materials. Finite element has been used for conducting pressure effect through parallel channel for knowing distribution effect pressing. The materials AA1070 and AA6061 powder matrix composite with Al2O3 nano fiber were used as reinforcement. Mechanical properties and scanning electron microscope were observed in room temperature pressure and in case where the temperatures were higher than recrystallization value. Both results were compared to determine the effectiveness of pressure on each process. The characterization of aluminum composites on the aspects and phenomena of the distribution of pressing effect on hot and cold conditions treasured by finite elements will be explained in this paper.

Restricted access

This paper presents an automated model and a project, Arrakis, for finding defects in shading algorithms for graphics rendering and compute workloads. A key challenge in shading algorithm testing is the lack of an oracle that can determine the quality and the output of a custom shading algorithm; this is crucial in graphics workloads because expensive assets are often wasted on solving these problems. A broad solution, Arrakis is developed, which builds on current graphics technology advances in Vulkan, SPIR-V and SPIRV-X by leveraging the standardization with mappings from SPIR-V and C++. Findings show that utilizing the demonstrated technology can improve quality whilst increasing productivity.

Open access
Authors: Yahya Fall, Mimoun Chourak, Seif-Eddine Cherif, Mahjoub Himi and Mohammed Rougui

Concrete is the most commonly used material in civil engineering, given its economic cost and ease of manufacture. Its strength depends on the characteristics of its constituents. A good mix makes it possible to build solid, durable and economical structures. The present work aims to characterize the gravel of the Eastern region (quarry of eastern Morocco) by granulometric analysis and water absorption. Then, the studied gravel is used to produce three types of concrete (B20, B25 and B30), which were assessed in terms of water absorption and compressive strength. The last step is to study the effect of an adjuvant, more specifically a water reducer, on mechanical characteristics of local concrete. B25 concrete was chosen for the last step since it is the most used type in the region. Results show that adding a water reducer adjuvant, in this case ‘Chrysoplast’, can improve the compressive strength of concrete if the percentage added is accurately determined.

Restricted access

Generally, engineering projects are getting bigger and bigger and more complex to handle. Due to the developments of information technology, managers have the opportunity to plan the execution of their projects and calculate the critical paths of those projects precisely, regardless of the types and sizes of their projects. However, these indicators are not realistic; in many cases the predetermined partial-deadlines cannot be kept, therefore the end of the project must be postponed. The aim of the research is to modify the inputs of the critical path method with the application of fuzzy values. The use of fuzzy values in business planning can support project managers in building the uncertainty factor into their model.

Open access

In the relevant literature there are many types of heat engines. One of those is the group of the so called hot air engines. This paper introduces their world, also introduces the new kind of machine that was developed and built at Department of Chemical Machinery, Institute of Energy and Chemical Machinery, University of Miskolc. Emphasizing the novelty of construction and the working principle are explained. Also the mathematical model of this new engine was prepared and compared to the real model of engine.

Open access

The building façade becomes an integral part of the concept for adaptation of the building to the climate conditions; it should be able to respond and adapt its properties and components with the immediate environment.

In the hot and dry climate in Algeria, the contemporary building design, materials, and techniques applied do not properly address the local climate conditions and the final energy consumption. Contrary to this, in traditional building practice, the local materials and passive strategies are used, which responded to the environmental context.

This study is focused on improvement of the cooling energy consumption of the contemporary buildings in Biskra City, Algeria. The traditional climatic façade solutions are investigated in order to adapt them to the contemporary buildings. To define and optimize the solutions, dynamic simulation with Vi-Suite add-on Blender 3D software was used. The results show a significant reduction in the cooling energy consumption, which confirms the use of the traditional techniques that can considerably improve the building efficiency.

Open access

Among nanotechnology-based thermal insulation materials thermodynamic performance of nano-ceramic coatings generates intensive discussions. Complete agreement has not been found yet about the mechanism of their insulating effect. In the Laboratory of Building Materials and Building Physics at Széchenyi István University (Győr, Hungary) heat transfer resistance experiments have been performed in order to describe thermodynamic processes inside nano-ceramic coatings. Previous studies finding after new measurements conducted in 2016-2017 also supported the former assumption that in case of nano-ceramic coatings convective heat transfer coefficient might be taken into account in a different way. Results also showed that thermal insulating effect of nano-ceramic coatings could be caused by a relatively high surface heat transfer resistance.

Open access

A new approach to the construction of a volume swept by the cutting tool is proposed for modeling 5-axis computer numerical control milling. A tool is considered to take the form of an arbitrary body of revolution. The main difference of the proposed approach is to provide the possibility of direct construction of the bulk synchronous parallel-dexel model, which, in turn, provides an effective modeling of the cutting process. Thus, it was possible to expand the scope of the given model by including the possibility to simulate arbitrary 5-axis computer numerical control programs. To confirm the correctness of the proposed approach, a program implementation of the corresponding algorithms has been performed. Examples of modeling of 5-axis milling processing of real parts and data on time costs for the suggested modeling are given. The high efficiency of the proposed approach is proven by the results of the experiments.

Restricted access

The Colonial Heritage is the subject of misconceived interpretations when exploring the historical legacy of French Algeria. The present research interrogates the complexity of the French strategies and the emergence of various architectural styles within the colonial context. The rehabilitation of the Sheridan Villa into an art residency emphasizes the aspirations of the study, from the architectural survey of the monument; to the monograph of its historical evolution, the results indicate severe cases of humid and physical pathologies menacing the stability of the construction. A significant number of similar monuments are dilapidated and hence call for coherent interventions; to upgrade their state of conservation.

Open access

The implementation of Directive 91/271/ECC concerning Urban Wastewater Treatment, leads to increase in the number of waste water treatment plants in Slovakia.The contribution is aimed at assessing the environmental impacts of the wastewater treatment process within the wastewater treatment plant using life cycle assessment. Life cycle assessment is an optional environmental management tool that focuses on the entire life cycle of a product and uses assessment methods to determinate adverse environmental impacts. The assessment of wastewater treatment plant is focused to the analysis of the individual factors identified by the physical-chemical analysis of wastewater. The correct application of the ISO 14040 standard assigns the accuracy of the analysis results and determines the individual elements of the system. Based on this ISO standard the system boundaries, the functional unit and the subsystems are defined.

Restricted access
Authors: K. Skowron, K. Grudlewska, D. Lewandowski, P. Gajewski, A. Reśliński and E. Gospodarek-Komkowska

L. monocytogenes poses a serious threat to public health, since most cases of listeriosis are connected with eating contaminated food. L. monocytogenes is often detected both in fresh and frozen vegetables.

The aim of this study was to evaluate the antibiotic susceptibility and ability to form biofilm of L. monocytogenes strains isolated from frozen vegetable mixtures in Poland.

Ninetynine genetically different strains were found among 100 isolates of L. monocytogenes. Among the 99 strains, 80 (80.8%) were susceptible to all tested antibiotics. Nineteen (19.2%) strains were resistant to one or more antibiotics. From this group of L. monocytogenes strains, most strains were resistant to erythromycin (16; 16,1%), penicillin (15; 15.1%), meropenem (12; 12.1%), cotrimoxazole (12; 12.1%), and ampicillin (3; 3.1%). According to the obtained results, differences in intensity of biofilm, both between those isolated in successive years and in the particular year, were observed. Performed analysis showed statistically insignificant faint negative correlation (r=–0.088) between the number of antibiotics to which strains were resistant and the intensity of biofilm formation by them.

Food contamination with L. monocytogenes poses a threat to consumers, therefore it is necessary to monitor their antibiotic susceptibility, ability to form biofilm, and genetic similarity, in order to evaluate the strains persistence time in plant.

Restricted access

A microwave-assisted ultraviolet sterilization system was developed to study the synergistic effect in the sterilization of milk. Electrodeless lamps emitting ultraviolet radiation inside the microwave chamber gave a synergistic effect without challenging food safety standards. This study compared the results of both microwave and microwave assisted ultraviolet sterilizations of milk in terms of various microbial tests and physicochemical properties. The microwave-assisted ultraviolet system was found to be more effective compared to microwave alone. A significant difference (P<0.05) was observed for total plate count and methylene blue reduction test between microwave and microwave assisted ultraviolet treatment from 5 to 15 secs. Microwave-assisted ultraviolet treatment decreased the microbial count exponentially and showed <1 log (CFU ml–1) after ten seconds of treatment. During the treatment period, no significant difference was observed in the physicochemical properties of milk.

Restricted access

While in developed countries research findings are available on the estimation of the realistic number of different diseases and their economic impact at social level, in Central and Eastern European countries these country specific data are neither sufficient nor reliable. This study partially fills the gap and gives a picture of the real number of foodborne salmonellosis in Hungary. In the spring of 2017, a survey about diarrhoeal and foodborne diseases was conducted by interviewing 1001 adults (over the age of 18). Our survey showed that approximately 18 times more individuals are suffering from Salmonella infection than it is assumed under the national and international epidemiological database. Based on our estimation, the annual number of foodborne salmonellosis may range from 91 242 to 105 606 in Hungary. In this paper a methodology has been developed to estimate the true occurrence of this disease. Our results can be used to calculate the costs-benefit ratios of future salmonellosis prevention programmes and inform decision-makers on the effectiveness of Salmonella-related measures in the area of food safety.

Open access

Utilization of algae includes both macroalgae for human consumption dating back to thousands of years, as well as the application of microalgae in health promoting dietary supplements. The autotrophic growth of microalgae is slow, but can be accelerated by optimizing their cultivation conditions. Efficiency optimizations for time and economy should be performed in many parallel experiments. A new high-throughput microalgae cultivation method is presented here, applying 24-low-well microplate with varying illumination, in which the cell growth is followed via evaluation of scanned images. A strain of the genus Nannochloropsis and two Chlorella vulgaris species have been chosen as well described and frequently applied model organisms in order to test the recently developed cultivation system. In these scaled down experiments, the custom design lighting panel was tested by studying the effect of the colour of illumination on cell growth kinetics. RGB LEDs (i.e. light emitting diodes, red: 622 nm, green: 528 nm, and blue: 467 nm) were used individually or together providing red, green, blue, and white colours. While the effect of light’s colour on algae growth was evaluated, also the new system was proven to be suitable for comparing maximal growth rates for different microalgae strains. While the tested two Chlorella isolates reached 1.2–1.4 g l–1 concentrations, the Nannochloropsis strain reached 1.4 g l–1 final cell dry weight, and specific growth rates were observed between 0.58–0.62 day–1.

Open access

The objectives of this study were to produce microencapsulated liquorice root extract (LRE) and determine storage stability of the product obtained. Maltodextrin (MD) and gum arabic (GA) as wall material were used to produce microencapsulated LRE by spray drying technology. Ratio of MD to GA was determined by response surface methodology. Three parameters: microencapsulation yield (MY), microencapsulation efficiency (ME), and Carr index as response were evaluated for optimization. MD emulsion was best for microencapsulation of LRE. Control emulsion was prepared without using any wall material. MD and control emulsions were stored for 6 months. Both preserved their bioactive and physical properties during storage. Total phenolic content (TPC) and antioxidant activity (AA) of MD and control emulsions ranged from 8.09–9.09 and 34.59–39.02 mg GAE/g (TPC); 44.78–51.27 and 136.13–171.08 mg TEAC/g (AA), respectively, during storage. Furthermore, moisture content, water activity, solubility, wettability, Carr index, and Hausner ratio of samples were found to vary between 1.54–3.12%, 0.16–0.32, 93.54–99.22%, 180–240 sec, 22.5–35.63, and 1.29–1.56, respectively, during storage. This study provides direct comparative data on properties of LRE powders produced without using wall material and microencapsulated using wall material by spray drying.

Restricted access

In this study, limonene was encapsulated by using gelatine, Na-alginate, polyvinyl alcohol, lactalbumin or xanthan gum with the uniaxial electrospinning process. The highest encapsulation efficiency was obtained for the sample containing polyvinyl alcohol. The release kinetic studies of nanofibre encapsulated limonene were carried out at 5.5, 20, and 38.5 °C. The Peppas equation expressed the release behavior of limonene for all systems very well, indicating quasi-Fickian diffusion. The modelling data suggested that maybe more than one mechanism was involved for the release at 20 °C. The activation energy for releasing limonene from the electrospun polyvinyl alcohol-alginate encapsulation system was found to be 6.2 kJ mol–1 from the Arrhenius equation.

Restricted access

The first objective of this study was to reveal the effect of temperature and time on the production of CLA isomers from safflower oil. For this purpose, CLA production was conducted at different temperatures (80–240 °C) and over different time durations (1–10 h). Alkali isomerisation gave a total conversion of 87.8% under the optimal conditions of 240 °C and 8 h (for maximum beneficial isomers), and produced 41.0% trans-10, cis-12, 40.4% cis-9, trans-11, and 6.4% undesirable CLA isomers. The second aim of this study was to determine the effect of temperature and solvents on the purification of CLA isomers. To achieve this, CLA solutions containing different solvents (acetone, methanol, and petroleum ether) were crystallized at several temperatures (0 to –85 °C). It was determined that although the highest CLA purities (94%) were obtained at –55 °C using acetone as the solvent with a yield of 38.1%, the highest yield (89.6%) was determined using petroleum ether at –85 °C with a purity of 88.1%. This paper presents methods to utilize safflower oil and low temperature crystallization process to inexpensively obtain beneficial CLA.

Restricted access

Apple cubes were osmotically dehydrated with 40 °Bx sucrose and sorbitol solutions. Light microscopy was used to observe the microstructure of fresh and osmotically dehydrated samples. Peleg’s model could fit the experimental data and describe the mass transfer kinetics of water loss (WL) and solid gain (SG). The use the sorbitol as osmotic agent, the increase of temperature and concentration of the solution increased the WL during the osmotic dehydration. The average cellular parameters, area and perimeter (size), and circularity, elongation, roundness, and compactness (shape) of fresh samples were 14.28±6.65×103 μm2 and 0.486 mm, and 0.73, 1.56, 0.70, 0.83, respectively. The osmotically dehydrated samples presented a decrease in area, circularity, roundness and compactness and an increase in the elongation of the cells, and these changes were higher in samples treated with sorbitol.

Restricted access
Authors: M. Chaalal, S. Ouchemoukh, C. Mehenni, N. Salhi, O. Soufi, S. Ydjedd and H. Louaileche

This study was carried out to determine the phenolic contents and the antioxidant activity of four nuts with different solvent extract. Total phenolic compounds, flavonoids, and proanthocyanidin were quantified. Antioxidant activity was evaluated by various in vitro tests, including ferric reducing power, phosphomolybdenum method assay, and free radical scavenging activity. The results showed that the total phenolic contents varied between 0.30 g GAE/100 g (peanuts) and 1.65 g GAE/100 g (walnuts); the flavonoid contents varied between 0.17 g QE/100 g (peanuts) and 0.41 g QE/100 g (hazelnut). The phenolic contents of four nut extracts exhibit potent antioxidant activity. Indeed, walnuts were the richest in total phenolic content and demonstrated the highest potential for overall antioxidant capacity using ferric reducing power assay (FRP), phosphomolybdenum method assay, and free radical scavenging activity (FRSA). Phenolic amounts positively correlated with antioxidant activity tested.

Restricted access

The study was designed to explore the antioxidative effect of pomegranate seed oil (PSO) at different concentrations (5 and 7%) against oxidation of plant-based oils (canola oil and sunflower oil) during storage (60 days) as compared to artificial antioxidant butylated hydroxyanisole (BHA, 200 ppm). Rancimat and Schaal oven analysis were employed for the assessment of potential consequences of PSO against oxidation in plant based oils. The variation in total phenolic contents (TPC), antioxidant activity, peroxide value (POV), and tocopherol contents during storage were evaluated by Schaal oven test at 62 °C. The substantially (P≤0.05) higher induction period (IP) values were observed for PSO blended oil samples as compared to blank oil samples. The addition of PSO in plant-based oils improved the oxidative stability by enhancing the antioxidant potential and TPC, decreasing POV, and slowing down the degradation of tocopherol contents during storage. The findings of the present study suggest that PSO might be used as an alternative potential antioxidant to synthetic antioxidants.

Restricted access
Authors: D.A.V. Amado, A.M. Detoni, S.L.C. de Carvalho, A.S. Torquato, C.A. Martin, T.S. Tiuman, C.M. Aguiar and S.M. Cottica

Avocado pulp is widely regarded as a great source of edible oil containing fat-soluble vitamins and omega-3 fatty acids (FA). However, avocado peel and seeds are also good sources of edible oil and are less explored byproducts. This paper aimed at determining the proximal composition, FA and tocopherol contents of the pulp, peel, and seeds of Quintal, Fortuna, Margarida, and Hass avocado cultivars. The pulps presented high concentrations of oleic acid. In addition, peel and seeds presented lower omega-6/omega-3 ratios than the pulp. There was also a considerable amount of tocopherol in the peel and seeds, especially in Hass peel (230.7 mg/100 g). According to the results, the peel and seeds of avocado that are considered byproducts, can be utilized in food industry.

Restricted access

It was the goal of this paper to introduce selected regulatory models concerning the legal status of trans fatty acids in connection with the consumer’s position and to propose some de lege ferenda conclusions.

Legislation, treatises, periodicals, and bulletins have been analysed. Information from portals associated with the European Union and posted on official websites of organizations like the WHO is presented.

As comprehensive descriptions of individual states’ approaches to trans fats’ presence in the human diet are not available, an attempt was undertaken to obtain as broad a range of positions as possible, of states willing to take part in the study. Alongside research based on responses from Health Ministries of the EU member countries and three states from outside the EU, its conclusions, observable trends, and solutions proposed to minimize content of trans fatty acids are an essential part of this study.

Analysis of legislation and positions on trans fatty acids presence in food submitted by the states demonstrated the need for a consistent, overall regulation of the issue. The authors relied on the information generated to outline such solutions.

Open access

During processing operations, honey can be exposed to excessive heat. That adversely affects the quality of product (its biological activity). The aim of this work was to test the possibilities of the use of dielectric properties (relative permittivity and dielectric loss coefficient) for honey overheating detection. Nine honey types obtained directly from beekeepers were investigated. Honey was heated at the temperatures 60, 70, 80, and 90 °C for 24 hours and then cooled down to 25–26 °C. At that temperature, dielectric properties of biological material under study were determined. In the frequency range 400 Hz to 4 kHz, the significant influence of thermal treatment temperature on both dielectric parameters was observed. Both dielectric parameters decrease as the heating temperature increases. The statistical analysis suggested that dielectric parameters can be used for distinguishing honey overheated from not overheated. Therefore, they can be potentially useful for honey quality assessment according to its overheating, e.g. in co-packing process. The proper frequency range for these parameters measurement is 1–4 kHz.

Restricted access

In this study, effects of novel casing, antimicrobials (chitosan and AgZeo) incorporated into multilayer polyethylene casing, on chemical and microbial attributes of sucuks were followed through 3 days of fermentation and 12 days of storage after heat treatment. Microbial growth was reduced by chitosan incorporated casing. Aerobic plate count (APC) of 8.81 log CFU g–1 on the 3rd day of fermentation was reduced to 2.60 log CFU g–1 by the end of storage. APC and lactic acid bacteria (LAB) were decreased significantly (P<0.05) by antimicrobial casings. The lowest concentrations of histamine and tyramine were observed (P<0.05) in sucuks stuffed into chitosan incorporated casing. These results show that antimicrobial casing could be used in sucuk production to improve its safety and quality.

Restricted access
Authors: F. De Sio, M. Rapacciuolo, A. De Giorgi, A. Trifirò, B. Giuliano, G. Morano, A. Cuciniello and G. Caruso

Research was carried out on processing tomato in Southern Italy in order to compare four round-prismatic type hybrids oriented to diced produce (4420, Miceno, Nemabrix, Impact as a control). The hybrid Nemabrix attained the highest marketable yield (180.9 t ha–1), due to both the highest number of fruit per plant and their mean weight (103.7 and 70 g, respectively), and it was not significantly different from the other genotypes in terms of processing efficiency both as a total and along dicing chain (67.8% and 65.6%, respectively). Lycopene attained the highest concentration in Nemabrix (155 mg kg–1), and β–carotene was most concentrated in 4420 and Miceno (2.8 mg kg–1). Significant differences arose between the genotypes with regard to the sensorial variables aspect, colour, taste, firmness, and fresh taste.

Restricted access
Authors: G. M. Taha, M. N. Rashed, M. S. El-Sadek and M. A. Moghazy

Abstract

BiFeO3 (BFO) nanopowder was synthesized in a pure form via a sol- gel method based on glycol gel reaction. Effect of drying and preheating temperature on preventing other phases was studied. Many parameters were studied as calcination temperature and time & stirring temperature as well. The prepared powder was characterized by X-Ray Diffraction of powder (XRD) and Transmission Electron Microscope (TEM). High pure BiFeO3 was obtained by preheated process at 400 °C for 0.5 h and calcination at 600 °C for 0.5 h without any impurities compared to dry at110 °C.

Open access

Adaptive solar shading systems have in comparison with the traditional systems of shading increased potential ability to improve the quality of the indoor environment and to increase the energy performance of buildings. Their extension allows all-around technological progress, but also the extensive application of large-scale glazing in building envelopes almost in all climatic regions. The literature review shows that the characteristics of the individual adaptive shading systems differ. Some have better performance in the sun protection or in improving the building's energy balance; others for example are better in glare elimination or in redistribution of daylight. The main purpose of this contribution is to provide a classification of the adaptive solar shading systems. In the article are compared merits and shortcomings of adaptive shading systems and are shortly analyzed assumptions of their wider application in central European climate conditions. Attention is also given to advantages and disadvantages, which brings the application of some kinds of adaptive solar shading systems. Several examples of adaptive shading systems are shown and briefly characterized.

Open access

The study focuses on an analysis of the future changes in short-term rainfall in the southwestern region of Slovakia. The analysis was performed for three climatological stations, i.e. Bratislava-Koliba, Gabčíkovo and Sereď, where short-term rainfall intensities with durations of 60 to 1440 minutes were analyzed using historical observations and future regional climate models. The study focuses on detecting changes in rainfall trends and changes in the values of the scaling coefficients. In final, there is a comparison of the design values of short-term rainfall derived for a future horizon with historical observations and the conclusion that rainfall intensities in the region analyzed will increase in the future and that this should be taken into consideration when designing water structures to ensure their safety.

Restricted access
Authors: Endre Salamon, Zoltan Goda and Tamás Berek

Unsuitable feed water quality causes fouling and serious decrease in membrane permeability during the operation of reverse osmosis filters, which leads to costly operation and low contaminant removal efficiency. The purpose of the experiment was to create a detailed, yet simple calculation scheme, suitable for higher education and everyday pilot experiments. The obtained formulas were calibrated against measured results, while investigating the fouling of the membranes at different iron concentrations. Pressure losses on a reverse osmosis equipment with a permeate capacity of 100 L/h were investigated for almost a year. Changes in permeability and cleaning methods were investigated with different feed water qualities.

Restricted access

Building life cycle assessment is getting more and more attention within the topic of environmental impact caused by the built environment. Although more and more research focus on the embodied impact of buildings, the investigation of the operational energy use still needs attention. The majority of the building stock still does not comply with the nearly zero energy requirements. Also, in case of retrofitting, when most of the embodied impact is already spent on the existing structures (and so immutable), the importance of the operational energy rises. There are several methods to calculate the energy performance of buildings covering the range from simplified seasonal methods to detailed hourly energy simulations. Not only the accuracy of the calculations, but the computational time can be significantly different within the methods. The latter is especially important in case of optimization, when there is limited time to perform one calculation. Our research shows that the use of different calculation techniques can lead to different optima for environmental impacts in case of retrofitting. In this paper we compare these calculation methods with focus on computational time, accuracy and applicability to environmental optimization of buildings. We present the results in a case study of the retrofitting of a middle-sized apartment house in Hungary.

Open access
Authors: Zuzana Németová, David Honek, Tamara Látková, Monika Šulc Michalková and Silvia Kohnová

The scope of this study is an evaluation of potential soil water erosion using the physically-based erosion model, EROSION-3D. This model is event-based and calculates soil water erosion during an actual measured rainfall event. The calculations of the erosion model take advantage of a digital elevation model, precipitation and soil parameters, which are established in a specific parameter catalogue. The soil water erosion was modeled in two small catchments in the Myjava Hill Land (Slovakia), using 9 soil moisture scenarios and two different crops on arable areas. When considering the last 35 years of rainfall records at the Myjava meteorological station, three storm rainfall events were applied in the modeling. The results were statistically analyzed to figure out the differences between the model’s functional possibilities; the modeling under the various scenarios proved a strong interaction between the values of the input factors and the results of the soil erosion.

Restricted access

The aim of the paper is primarily to evaluate the heating energy demand of an industrial hall. In the study, we have made multidimensional dynamic whole building simulations for describing coupled heat and moisture behaviour and energy consumption of the building with different internal loads and compared to the calculated energy consumption of the building according to the Hungarian and Austrian regulations. The walls and roof structure of the industrial building were made with insulated panel systems, the plinth wall was built with monolithic reinforced concrete with 12 cm of XPS insulation. The floor is made of steel fibre reinforced concrete, where 10 cm XPS perimeter insulation was applied. After the calculations, we insulated the floor on the whole surface with 10 cm XPS and investigated the modified structure’s heating energy demand too. In the paper, we analyse the energy consumption of the original and modified industrial building according to the monthly and seasonal calculations and the whole building dynamic simulations and evaluated the differences. Furthermore, we assessed the effect of internal loads, thermal bridges on the simulations.

Open access

Building envelopes have a significant role in the protection of interiors against weather conditions. While wind, rain barriers and barriers against excessive heat gains were constructed from insufficient elements in the past, the current requirements for envelope functions are different. New materials and technologies allow for more complex design and evaluation of parameters in regard to the needs of occupants and economical interior performance.

This paper is focused on the daylighting solutions inside lit office space in which renovation of the lighting system is expected. Several retrofit scenarios based on window shading variations and lighting systems are investigated. Achieved results are evaluated from the point of view of energy demand. The integrative multi-platform tool, the Lighting Retrofit Adviser (LRA) is applied to calculate energy renovation preferences and to accept decision.

Open access

The study of respiratory forms a major application and publication in the medical field. It characterizes the abnormalities in the breathing pattern, which assists in selecting the appropriate treatment methods. In some cases, respiratory characteristics unravel and point out potential diseases. A medical team gathered data from randomly selected recruits. A huge dataset was prepared, which capture the volume and velocity of the breathed air from the target recruits. This paper presents the results of carrying out some of the signal processing, dimension reduction, and data mining techniques over this dataset. In particular, convolution filter, singular value decomposition and density-based spatial clustering of applications with noise were applied. Inhaling behaviors have been categorized into nine groups but with stochastic noise. Some of the groups are big enough and distinguishable to evaluate with the use of eight types of inhalers the model for velocity versus volume of inhaling. Results will be considered by the medical team for choosing the appropriate inhaler out of five types of inhalers appropriate for each group.

Restricted access
Authors: U. Pont, S. Swoboda, A. Jonas, F. Waldmayer, P. Schober, H. Priebernig and A. Mahdavi

A successful coupling of architectural design with multi-aspect building performance assessment is a complex, but necessary requirement for today’s building planning- and retrofit-activities. Architects are required to not only possess the vocabulary and basic knowledge in multiple fields, but must also work in collaborative design teams, composed of different domain specialists (e.g., structural engineers and building simulation experts). However, training in collaborative work is rarely provided in academic surroundings. In this contribution, we describe an educational effort toward interdisciplinary work on a specific and clearly defined architectural design task, which strongly necessitates the consideration of performance mandates. The task is the retrofit and redesign of an existing building façade from the 1950s. “Rationalist” buildings of this period often display reasonable functional solutions and good daylight availability, but they have performance shortcomings in other areas. These encompass, for instance, poor thermal performance of the envelope, lack of sufficient indoor environmental control, and unsatisfactory overall appearance. In a combined design studio and project course for building performance modelling, students from different disciplinary backgrounds formed interdisciplinary design teams. These teams worked together on façade retrofit ideas for the aforementioned building, considering both aesthetic aspects and performance issues from the very first design sketch. This led to the development and performance evaluation of a number of original façade retrofit ideas. In addition, the students were asked to devise the building process management. They thus had to consider not only design issues, but practical matters of building construction. The present contribution illustrates the scope, the applied approaches, and the concrete results of this interdisciplinary academic effort.

Open access

Concrete beams reinforced with glass fiber-reinforced polymer bars exhibit large deflections and crack widths compared with concrete members reinforced with conventional steel. In this work, the current design methods for predicting deflections under loading and crack widths are developed using the same theory with some additional parameters. Based on the research work presented in this paper and past studies, a theoretical correlation for predicting the crack width and deflection is proposed by testing six concrete beams; specifically two sets are reinforced with different glass fiber-reinforced polymer of reinforcement ratios and one set is used as the control beam. The research objective is to analyze the behavior of the beams under loading and obtain the differences in their behavior in terms of the following parameters: deflections; cracks, and general bearing capacity.

Restricted access
Authors: Patrik Márk Máder, Olivér Rák and István Ervin Háber

The algorithms are the part of the life which could give a solution for simple and complex problems. Most of the ways are easy, but the basics are always made by predetermined steps. The peculiarity of the sciences can be explained with these process-based principles. The following rules are the same in the architecture also. Nowadays the algorithms are more improved the fact of the expectations of the 21st century. The creator can make a lot of rules which can support the workflow with the correct logical connections.

Since the computer aided design became available, the relationship between the architecture and information sciences getting stronger. To solve the most of the problems, it needs information technology programing techniques, logical methods and algorithms. The free geometric design, the compliance constraint with economic aspects, analysis and the optimization processes require new solutions.

The article will give an overview about the expectations of the future architects along the general knowledge and the practical examples. The study will show the development of the new professions according to the increased amount of data. Examine the competence of the contemporary architects and look for the issue of ‘the architect is a programmer.’

Restricted access
Authors: A. Lupíšek, J. Růžička, J. Tywoniak, P. Hájek and M. Volf

The main objective of the present research was to develop a methodology for assessment of resilience of residential buildings in Central Europe. The main purpose of the methodology is to enable to set performance levels in terms of resilience for new multifamily residential buildings. The paper describes a method of selection and development of the assessment criteria and the final structure of whole assessment scheme and presents examples of detailed evaluation using selected criteria.

Open access

Urban density and its impact on the availability of daylight and direct sunlight in a residential building. The light comfort in the living spaces and the insolation of flats, the requirements. Influence of outdoor light intensity on the intensity of daylighting in the living spaces. Dimensional, shape, and layout solution of a residential building in the area with extremely high external shading by surrounding development – a case study.

Open access
Authors: Marija Mihaela Labat, Lenka Korbeľová, Silvia Kohnová and Kamila Hlavčová

The aim of this paper is an assessment of the susceptibility of soil to soil erosion, proposed measures against soil erosion, and an assessment of their effect on the reduction of peak flows. The area of interest is the Halúzníkov Creek basin. The calculations of the soil loss from water erosion were done using the universal soil loss equation and universal soil loss equation 2D methods; for estimating design floods, the curve number method was applied. For reducing the soil loss to tolerance values, strip cropping measures on agricultural fields were proposed. After applying the strip cropping measures, the design flood peaks were also reduced.

Restricted access

The aim of this paper is to introduce the design steps and implementation details of a system, which combines modern web-technologies and open-source simulation software to create a virtual laboratory framework. In order to validate the functionality of this framework and to demonstrate its capabilities, a classic experiment from the field of control theory was implemented; the inverted pendulum. In this experiment, a simulated controller keeps the rod of the pendulum in an upright position. Users can change different parameters of the model and then test the impact of these changes in a very intuitive and interactive way, by applying force to the pendulum model in 3D and observing the behavior of the controller.

Restricted access

Apple is one of the most important fruit grown and consumed in the temperate climate region. About 2% of the European population suffers from several allergenic reactions after consumption. Presence of 7 members of Mal d 1 gene family occurring in some apples was examined by PCR. The Mal d 1.01 and 1.02 genes could be detected from 91% and 79% of apple cultivars, respectively, due to the high degree of conservative regions. The Mal d 1.04 gene has 4 functional varieties and 2 pseudo-alleles, so it is highly variable. The PCR amplifi cation with Mal d 1.06 primers gave one or two fragments with different sizes. The electrophoretic pattern is a suitable means to select apple cultivars according to their low, medium, or high Mal d 1 allergen content. Florina apple showed the single 154 bp allele, which is responsible for the small Mal d 1 allergen content in homozygote form..

Several samples gave weak signal or did not give any fragment-band on the gel, so Mal d 1.07 and 1.08 genes might have more varieties. Regarding the Mal d 1.09 gene we have found that it has conservative sequences in different apple cultivars and does not have too many varieties.

Open access

The aim of the study was to analyse the flavour profile and general lust of innovative dairy products – kefir, which has increased health-oriented values resulting from an increase in the ratio of whey protein and an enzymatic bioconversion of lactose. Kefir was prepared from a mixture of goat milk and its permeate concentrated with microfiltration and ultrafiltration processes, combined in a ratio of 6:4. The permeate addition increases sweetness and reduces overall flavour of the dairy. The enzymatic conversion of lactose into galactooligosaccharides further increases the sweetness of the dairy mixture, while simultaneously weakening the odours both goatish and processed.

Restricted access

Meriç River Delta is located in the Thrace Region of Turkey, and it is one of the most important wetlands worldwide. Gala and Sığırcı Lakes, which are known as significant lakes in Turkey in terms of especial biodiversity, are located in the Meriç River Delta and they are the main lentic factors of the system. The aim of this study was to evaluate the essential and toxic element bioaccumulation levels in fishes of Gala and Sığırcı Lakes from a statistical perspective by investigating a total of 25 macro- and micro-element bioaccumulations. One-Way ANOVA Test (OWAT) was applied to detected data in order to determine the statistical differences of element bioaccumulations among the fish species. Cluster analysis (CA) was also applied to detected data in order to classify the investigated elements in terms of bioaccumulation levels in fish tissues. According to the results of OWAT, although statistical differences were not recorded among the fish species in terms of essential element levels, significant statistical differences were recorded in terms of toxic element levels (P<0.05). According to the results of CA, 5 statistically significant clusters were formed, which were named as “Most intense elements”, “Second most intense elements”, “Moderate intense elements”, “Second rarest elements”, and “Rarest elements”. It was also found that toxic element bioaccumulation rates in fishes of Gala Lake were significantly higher than in fishes of Sığırcı Lake (P<0.05).

Restricted access

The current development of smart buildings is conditioned by the development of smart technologies, bringing many new phenomena into the construction industry that change ownership, user and management environments. The optimized and truly functional smart building already includes engineering and non-technical aspects, which must, however, be respected during all life cycles. This requires the emergence of completely new expertise or the extension of the existing expertise, including facility management. Smart buildings enable cost savings and facilitated operation to facility management. Moreover, smart buildings also contain significant multidisciplinarity, especially in pertaining technical areas. This requires the facility manager to monitor individual disciplines and ensure their interoperability and optimal functioning to meet the needs of building users.

This contribution is based on practical experiences and focuses on the analysis of the new demands that smart buildings require in management issues, the evaluation of synergies between smart buildings and efficient facility management for maximizing the use of the building and its sustainability. It also quantifies the benefits of facility management for the operation of smart buildings and their utility value, depending on the degree of integration of services.

Open access

A novel functional pumpkin-based beverage fermented by Lactobacillus mali K8 (FPJ) was produced. FPJ possessed higher ferric reducing antioxidant power (FRAP, 270.76 μM TE/100 ml) and radical scavenging activity (RSA‒IC50, 7.56 mg ml‒1) compared with non-inoculated control (PJ) (102.99 μM TE/100 ml and IC50 52.78 mg ml‒1). Up to an IC50 of 23.71 and 5.27 mg ml‒1 of α-amylase and α-glucosidase inhibitions were demonstrated by FPJ, close to that of acarbose (IC50 4.86 and 0.048 mg ml‒1, respectively). Oral administration of FPJ significantly lowered post-meal blood glucose levels in low-dose streptozotocin (STZ) and high-fat diet-treated rat – a reduction of incremental areas under the curve 2334 versus 2689 mmol min l‒1. Thus, it may open new dietary measure in managing postprandial hyperglycaemia.

Restricted access

Insects are alternative protein sources as nutritious novel food. However, there are some risks associated with the consumption of insects, even if rearing in controlled systems. Except for a recent EFSA opinion on the safety of insects as food, the European law is not conclusive regarding using insects as food products. Insects may be associated with microorganisms, but the prevalence of pathogens is usually lower than in case of other animal proteins. Insect proteins can induce allergic reactions, but only few studies are available on allergic reactions due to insect ingestion, and direct hypersensitivity to insect protein has not been proven. Some insect species are considered toxic, because some toxic substances are accumulated from toxic plants or are synthesized by the insects. However, there are few reports available about adverse reactions caused by insect consumption. Insects and insect derived food products may contain hazardous chemicals such as heavy metals, dioxins, mycotoxins, plant toxins, biocides, and veterinary drugs. However, data on hazardous chemicals in reared insects and accumulation of chemical contaminants from the substrates are limited. This review is not demonstrating the safety of insects as a food category, but the possibility of insects for human consumption with no more hazards than other animal products.

Open access

The energy consumption of residential buildings represents the majority part of energy usage in Egypt. The aim of this study is to assess the energy performance of a dwelling in New Minia City, Egypt through different orientations. The energy consumption of the case study building is 52560 kWh annually. However, this energy demand could be reduced by 5.8% if the building is oriented to the north direction. The difference of the energy consumption between the best and the worst building orientations, North and South, respectively, reached up to 7.5%. The location of the actual building has a noticeable effect on the energy consumption.

Restricted access

Summer overheating is usually caused by a combination of factors, such as building location, orientation, fabric, ventilation and occupancy behaviour. People by their behaviour influence overheating through the internal heat gain mode and window opening ventilation mode. The article describes several types of occupancy profiles according to their behaviour taken from the literature: the profile of the worker, the child, the pensioner and the adventurer. From them, it is possible to disable the heat gain schedule for the whole household or apartment house. Heat gains from appliances are updated according to the modern lifestyle and current household appliances. The effect of heat gains in combination with other factors, which caused overheating, is further evaluated through the building simulation program.

Open access

Management of construction enterprises requires experience or managerial competencies. To achieve successful results of construction enterprises and projects, for example as cost reducing, increasing revenues, shortening construction time, both are necessary. Building information modeling represents technology for developing of managerial skills for managers. Main aim of research is to analyze and quantify the management decisions based on managerial competencies developed through building information modeling on results of construction enterprises in Slovakia. Cost reducing, increasing of revenues and shortening construction time are main monitored by enterprise and project results. Research hypotheses are based on the assumption that building information modeling has a positive impact on development of managerial competencies and skills and manager’s t decisions.

Restricted access
Authors: O. Šikula, O. Ladjedel, P. Charvát, L. Adjlout and S. A. Reffas

Dynamic heating computer simulations of one model typical living room heated alternatively by two types of heating bodies are presented in this paper. This contribution describes a numerical model of two heating elements (plate radiator and a new type of convector) showing different thermal inertia by using the TRNSYS software. The results show energy savings approximately of 10% for the new tested convector, where the thermal comfort is better in terms of reaching the required room temperature.

Open access

Between November 2016 and April 2017, 240 H5N8 outbreaks of highly pathogenic avian influenza have been registered in Hungary resulting in the culling of 3.45 million poultry. Aiming at the prevention of the reoccurrence of the public scare experienced in regard of the H5N1 outbreak in 2006, in 2016 a more proactive and responsive communication activity has been implemented, which resulted in a total of 1661 media appearances. For consistent and credible information, all press inquiries were answered by the Chief Veterinary Officer of Hungary, and journalists received the requested information usually within 8 hours. In order to understand how effective communication methods help to stop decrease of poultry meat consumption, determinative factors according to consumer risk perception and changes in poultry meat consumption were identified. Analysis of the consumer survey conducted in 2016 showed that education and gender were the most important socio-demographic variables, though poultry consumption was almost completely undisturbed. The results of the 2016 consumer survey were compared to a corresponding dataset published on the 2006 avian influenza public scare, which showed 12.6% increase in the number of those respondents, who have not changed their consumption behaviour due to avian influenza.