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The current work focuses on a Hungarian clothing manufacturer’s problem. First the industrial problem is presented; its corresponding critical pass method graph is depicted. To answer all emerging questions with respect to alternative possibilities, a large number of critical pass method problems have to be solved cumbersomely. Instead, first this graph is transformed into a process network. Alternatives specified by mainly financial necessities as well as human resource constraints can now be easily managed, namely where specific activities can be performed in different ways by various employee having different qualifications, requiring different durations and obviously respective costs can be considered within this model. These separate cases can commonly be handled within the resultant sole process network and the corresponding mathematical programming model.

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The resource management in a dynamic environment is a really complex problem. If semantic constraints are taken into account the complexity increases significantly. The problem definition of resource management using semantic constraints in the subject domain is demonstrated by means of an example of manufacturing scheduling. The application of multiagent approach is suggested and examined to solve the resource management problem. Experiments simulate two types of calculations of the resource allocation problem in manufacturing scheduling: the multi-agent approach and the sequential calculations. The experiments have demonstrated the effectiveness of multi-agent approach to solve the above defined problem.

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Authors: Mimoza Sylejmani, Gabriella Medvegy and Lulzim Beqiri

The paper deals with the analysis of the fortified dwellings - Kulla, which were constructed in Kosovo since XVIII–XIX century. As a case study, one took the Kulla, which were constructed in the Plain of Dukagjin. These types of dwellings were not constructed solely in Kosovo, but also in other countries of the region, that is: Northern Albania, Macedonia, and Montenegro. In Kosovo, the major parts of these buildings were constructed in the Plain of Dukagjin. Usually these buildings were constructed in two and three floors.

Characteristic feature of these buildings is the division of functions in vertical direction.

The research is based on the literature, analysis of the buildings, the research that was done up to now, including the interviewing of the persons-owners of the Kullas.

The aim was to get an understanding on the purpose of constructing the Kulla in vertical manner.

Kulla was analyzed in functional, architectural, constructive and condition aspect, which it offers to its inhabitants. There are a lot of factors that influenced on the construction of these buildings, one of them being the climate. Kosovo is characterized by a harsh climate during cold season of the year, which influenced on the relatively low height of the floors. Another feature is limited lighting in the ground floor, which increases steadily going further up to the last floor, as well as through the embrasures used for fire arms.

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A methodology is proposed to calculate statistical average and standard deviation of long time water quality parameter series along a river network. The method considers the water network as a graph consisting of straight sessions and junctions. With a Taylor-series approximation, statistical values of an arbitrary point of the network can be calculated from upstream ones without the need to calculate the single downstream values. According to preliminary results of the first calculations on a pilot area, mean value of the downstream biological oxygen demand and the so called ‘transfer coefficient’ can be approximated with a relative accuracy of 10%.

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From nanotechnology-based thermal insulation materials nano-ceramic thermal insulation coatings are generally considered to be the most critical because of contradictory technical data that could be founded in special literature. Complete agreement had not been already found about the mechanism how does their insulating effect take. In the Laboratory of Building Materials and Building Physics at Széchenyi István University (Győr, Hungary) several thermodynamic tests were made in order to find out thermodynamic process inside this material. Several building structures with different order of layers were tested with heat flow meter. Results showed that convective heat transfer coefficient cannot be taken account in usual way using this material as thermal insulation.

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E. coli is one of the major pathogenic bacteria that cause diarrhoea in human. Traditional fermented foods, e.g. Ogi, has been used indigenously to treat diarrhoea. This study was aimed at investigating the antagonistic activity of selected lactic acid bacteria (LAB) isolated from three varieties of ogi against multidrug resistant E. coli EKT004.

Antibiotic susceptibility of the tested E. coli EKT004 strain to ofloxacin, gentamycin, cefuroxime, ceftazidine, lincomycin, oxacillin, cloxacillin, cefotaxime, ciprofloxacin, and nitrofurantoin was tested by disc diffusion method. E. coli EKT004 was co-incubated in two different experiments with Weissella paramesenteroides, Lactobacillus plantarum, and L. fermentum that have been previously isolated from Ogi. An 8 h old E. coli was introduced into an overnight culture of LAB and a fresh E. coli was inoculated into overnight culture of LAB. Viable count of pathogen at 0 h and after 24 h co-incubation at 37 °C was observed.

The tested E. coli EKT004 was resistant to cefuroxime, ceftazidime, lincomycin, oxacillin, cloxacillin, and cefotaxime. The tested LAB isolates have a broad spectrum of activity against E. coli EKT004 used for the study with a decrease of 6–8 log of E. coli as compared with the control. These results indicate a direct effect of lactic acid bacterial strains on multidrug resistant E. coli strain.

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Authors: R. Magalhães, V. Ferreira, G. Biscottini, T.R.S. Brandão, G. Almeida and P. Teixeira

Contaminated food with Listeria monocytogenes is the predominant route of transmission of listeriosis to humans, a severe illness with a high mortality rate. Food processing environments can be colonized by persistent strains, repeatedly isolated for months or years. This study aimed to investigate the biofilm formation capacity of six strains of L. monocytogenes that persisted for long periods in two cheese processing plants in comparison to seven strains isolated sporadically from the same plants. Persistent strains produced more biofilm than non-persistent strains on stainless steel and silicon rubber surfaces; no significant differences were observed on polyvinyl chloride (PVC). In a polystyrene microtiter plate assay with crystal violet staining, no evidence was found that persistent strains have higher ability to form biofilm than non-persistent strains, and no correlation was identified between biofilm formation in the microtiter plate and on the three other surfaces tested.

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Authors: J. A. Pino, P. Winterhalter, R. Gök and J.C. González

The volatile compounds in commercial rums declared as aged 3, 7, 10, and 15 years were isolated by solvent extraction followed by solvent-assisted flavour evaporation and analysed by gas chromatography-olfactometry. According to the aroma extract dilution analysis, 19 potentially aroma-active compounds in the flavour dilution (FD) factor range of 8 to 1024 were found. Fifteen of them were present in at least one aged rum at FD factor≥128. Clear differences in the FD factors of these odourants between each of the aged rums suggested that they contributed to their unique sensory profiles.

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The inhibitory effects of phytic acid (PA) on the browning of fresh-cut chestnuts and the associated mechanisms of PA on polyphenol oxidase (PPO) and peroxidase (POD) activities were investigated. The enzymatic browning of chestnut surfaces and interiors was suppressed by soaking shelled and sliced chestnuts in a PA solution. The specific activities of PPO and POD extracted from chestnuts declined due to inhibition by PA. PA was determined to be a competitive inhibitor of both PPO and POD by Lineweaver-Burk plots. The binding modes of PA with PPO and POD were analysed by AutoDock 4.2.

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Authors: P. Olejníková, A. Kaszonyi, M. Šimkovič, B. Lakatoš, M. Kaliňák, M. Valachovičová and L. Birošová

The human endogenous intestinal microbiota is an essential “organ” in providing nourishment, regulating epithelial development, and instructing innate immunity. Even though lots of scientists have evaluated the content of gut microbiota from various points of view, we examined the content of intestinal microbes in the group of healthy middle aged volunteers (40–60) form Slovakia. We have compared faecal cultivable microbiota of vegetarians and omnivores. We have found that the composition of the human microbiota is fairly stable, and it seems that the major microbial groups on species level that dominate the human intestine are conserved in all individuals regardless of dietary habits. Beside the microbial content we have examined the faecal samples also for the presence of antimicrobial active compounds, potential mutagens, and faecal sterols.

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Authors: B. Nagy, J. Soós, B. Horvath, M. Kállay, B. Nyúl-Pühra and D. Nyitrai-Sárdy

During the ageing in barrels, the contact with the fine lees triggers several processes in wine. Lees has a reductive effect by absorbing dissolved oxygen and reducing the amount, which will remain in the wine. At present, minimizing the addition of sulphur dioxide is the trend in all viticultural areas. In this study, the effect of various sulphur dioxide levels was monitored in presence of the lees to determine which dose is appropriate to provide the protection of susceptible white wine against oxidation.

Without SO2 protection, the rH and redox potential changed slightly, so the level of dissolved oxygen seemed to be controlled during the ageing period by the lees, though the antioxidant effect of lees in itself was not appropriate to protect the polyphenol content from chemical oxidation, which led to considerable browning. With the addition of a lower amount of SO2 — 40 mg l2, the lees is already able to protect the white wine samples in all aspects.

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In this research, simultaneous contribution of long-chain inulin (0–2.34%) and modified starch (0–0.58%) on the physical stability and rheological properties of doogh within 30 days of production was studied. Increased concentration of both hydrocolloids redounded to improvements in physical stability, apparent viscosity, flow behaviour, and viscoelastic properties compared to the control sample. Fitting the data to Herschel—Bulkley model showed a decrease in flow behaviour index, while consistency coefficient (k) increased. Furthermore, for samples containing inulin and starch, G′ was greater than G″, unlike control sample. Indeed, contribution of long-chain inulin at concentrations above 1.18% and modified starch at above 0.3% promote the formation of gel network structure. The expected viscosity increases in the continuous phase in the presence of starch, and also the interactions established between inulin and yoghurt casein aggregates seem to be responsible in the improvement observed in physical characteristics of the product. Among the concentrations studied here, two samples, containing 2% inulin and 0.5% modified starch and 1.18% inulin and 0.58% modified starch, respectively, were recognized as functional doogh samples presenting premier physicochemical and rheological properties.

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The aim of this research was to study the shelf-life of fresh-cut iceberg lettuce, testing a packaging film manufactured with and without addition of anti-UV compounds, and using two different protective atmospheres (N2/CO2 70/30% and Ar/CO2 80/20%). In order to simulate the most common retail storage conditions, the samples were stored at 6 °C under artificial light by using real supermarket refrigerated exposition stands. The data obtained showed that the use of an anti-UV film always causes a lower quality decay of the product; in any case, the best results were obtained when the anti-UV film was utilized in association with the packaging atmosphere consisting of Ar and CO2 (80/20%) gas mixture.

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Authors: J.M. Garcia, S. M. Castro, R. Casquete, J. Silva, R. Queirós, J.A. Saraiva and P. Teixeira

The effect of sequential treatments of pressure (50–150 MPa, 10 ºC, 5 min) and temperature (57 ºC, 15 min) on the survival and bacteriocin production of Pediococcus acidilactici HA-6111-2 cells in the exponential growth phase was assessed. The growth curves were fitted with the modified Gompertz model, and the estimated maximum specific growth rate was considered to be pressure dependent. A delay in the maximum value of bacteriocin production was registered for more severe pressure conditions, but it was found more notorious for pressure followed by temperature treatments. At lower pressure intensity treatment, regardless of the application order, there was an enhancement of bacteriocin production per cell when compared to the control while maintaining the maximum production value. Bacteriocin production after the treatments can be described by an exponential model.

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Enzyme-assisted extraction of carotenoids from tomato peels of the Bulgarian cultivar “Stela”, one of the most widely used cultivars by the canning industry, was examined in this study. The carotenoid content in raw tomato peels was established by HPLC analysis. A two-step protocol was followed: the tomato peels were first treated with enzymes and then extracted by the use of acetone as a solvent for 30 min at 20±1 °C and solid/liquid ratio of 1:30. The total carotenoid, lycopene, and β-carotene extraction yields were increased by the use of pectinase, cellulase, endo-xylanase, and proteinase enzymes in comparison with the non-enzyme-treated samples. The increase in the extraction yield was affected by the enzymes used, the enzyme concentration, the pretreatment time and temperature. Maximum total carotenoid (55.15 mg/100 g d.w.), β-carotene (35.85 mg/100 g d.w.), and lycopene (15.44 mg/100 g d.w.) extraction yields were obtained in peels pretreated with mixed cellulase (100 U g−1) and endo-xylanase (400 U g−1) for 4 h at 50 °C. Carotenoid recovery by mixed cellulolytic and hemi-cellulolytic enzyme pretreatment of tomato peels is a good approach, which can be used for waste utilization.

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Determination of consumers’ acceptance level of sushi meal among Czech respondents was the main aim. The survey included 1352 respondents that filled in a questionnaire on their demographic characteristics and food preferences regarding their acceptance of sushi meal. Additionally, 79 volunteers participated in sorting sushi among other 14 popular meals in the Czech Republic, according to their assumed situations. The results indicate that sushi is highly accepted among Czech consumers (more than 80% of respondents consume sushi) due to sensory characteristics and health benefit claims of sushi. The main barrier for sushi acceptance is sushi being a cold meal. The study emphasized that sushi price highly influences not only consumption frequency but also acceptance of sushi among respondents who declared not consuming this type of meal.

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Supercritical fluid extraction (SFE) was used for fractionation of grape seed to be applied in natural products of the food, cosmetic, or pharmaceutical industry. A two-step process was developed, consisting of conventional alcoholic extraction followed by SFE with carbon dioxide. The effects of pressure and concentration of co-solvent (ethanol) at constant temperature and solvent to feed-ratio were evaluated. The antioxidant activity of extracts and raffinates was measured with the DPPH* free radical scavenging assay. It was observed that supercritical carbon dioxide can be used in the described process for fractionation of an alcoholic grape seed extract to obtain a product with noticeably high antioxidant activity and a second one with no antioxidant activity or pro-oxidant activity.

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Changes in the consumption habits of the population forces food industry to produce traditional products in modern ways, sometimes not taking into account the modified safety issues. The aim of this study has been to compare hazards and critical control points for traditional and industrial cremeschnitte production. The result shows that the traditional cremeschnitte production includes two additional critical control points, cooking and moulding of egg cream basis, which is essential for safety. In addition, the results of microbial analysis pointed out that the traditional cremeschnitte is safer than the industrial one produced from dried cream powder when comparing Escherichia coli, total aerobic count, and mould contamination (P<0.05). Moreover, our controlled contamination test with E. coli of raw material shows that the traditional cremeschnitte production process reduces microbiological hazard even in the worst-case scenario. All this indicates that traditional food safety practices are not granted and should not be neglected in new production technologies.

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Authors: L. Cuevas-Glory, M. Bringas-Lantigua, E. Sauri-Duch, O. Sosa-Moguel, J.A. Pino and H. Loría-Sunsa

In this study, production of sour orange juice powder utilizing a spray dryer was investigated. To prevent stickiness, maltodextrin DE 12 was used as a drying agent. While feed flow rate, feed temperature, and air flow rate were kept constant, inlet air temperature (120–160 °C) and maltodextrin content (maltodextrin dry solids/100 g feed mixture dry solids; 10–20%, w/w) were selected as the independent variables. Product properties investigated included ascorbic acid, volatile compounds, and moisture content. Ascorbic acid retention, volatiles retention, and moisture content were used in optimization of the process by response surface methodology. The optimum inlet air temperature and maltodextrin content were 156 °C and 20% w/w maltodextrin, respectively. This study revealed that by applying these optimal conditions, sour orange juice powder with 81.5% ascorbic acid retention, 5.5%, w/w moisture content, and 78% volatiles retention was produced.

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Authors: L. Darnay, A. Tóth, B. Salamon, K. Papik, G. Oros, G. Jónás, K. Horti, K. Koncz and L. Friedrich

The aim of this study was to show how microbial transglutaminase (mTG) can be used as an effective texture-modifier for two popular Hungarian products: Trappist cheese and frankfurter. In both cases we investigated how components of these products, milkfat in cheese and phosphate in frankfurter, can be substituted by mTG. Therefore, Trappist cheese samples were produced from cow milk of 2.8%, 3.5%, and 5% milk fat. The effect of ripening was evaluated with Texture Profile Analysis (TPA) and sensory evaluation (scoring test, 10 trained panellists). Springiness and cohesiveness values were significantly higher by enzyme-treated semi-hard cheese samples at lower milk fat levels. Sensory evaluation showed that the enzyme-treatment led to higher scores by cheese samples made from cow milk of 3.5% and 5% milk fat. Frankfurter was made with 0.1%, 0.3%, 0.5%, and 0.7% tetrasodium pyrophosphate, and partly enzyme-treated with 0.2% commercial mTG enzyme preparation. Our results showed that mTG is able to significantly improve hardness and crunchiness by frankfurters made with 0.1% phosphate addition. Our sensory evaluation suggests that mTG and phosphate should be applied in combination in order to have a final product with recognisably more homogeneous texture.

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Authors: Y. Zhang, W. Zheng, Q.C. Ying, L.-E. Shi, Z.-L. Zhang, M.-Z. Shi and Z.-X. Tang

The sub-acute toxicity of E. faecalis HZNU P2 was investigated in rats fed with different doses for 14 days. To evaluate the acute oral toxicity of E. faecalis HZNU P2, rats were fed with E. faecalis HZNU P2 at a high dose of 2×1011 CFU kg−1 for 10 days. Results showed that there were no abnormal clinical signs in any of the groups during the experiment. There were no significant differences in live weight gain among rats fed with E. faecalis HZNU P2, compared to those in control group. Macroscopic or microscopic examinations of organs revealed no abnormalities, indicating that E. faecalis HZNU P2 did not adversely affect the health of rats. Results of this study demonstrated that digestion of E. faecalis HZNU P2 in rats did not show any obvious signs of toxicity.

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The efficacy of 1-MCP on apricots at different treatment temperatures and days after harvest during 6 weeks of storage at 1 °C was investigated. On the 1st, 3rd, or 5th day after harvest, fruit were treated with 1-MCP at 1 °C for 24 hours. In order to evaluate the effect of temperature, apricots were exposed to 1-MCP at 1, 10, and 20 °C (on the 1st day after harvest). 1-MCP application reduced the ethylene and CO2 production and delayed softening. Fruit treated on the 1st day after harvest presented the highest firmness at the end of the experiment. No significant effect of treatment temperatures on apricot quality was observed. The time period between harvest and 1-MCP application could be delayed until the 5th day after harvest. Results showed that 1-MCP extended the storage life and maintained the overall quality of apricot during storage and shelf-life.

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This study was performed to evaluate the effect of lactococcin BZ and enterocin KP against Listeria monocytogenes ATCC 7644 in skim (0.1%), half (1.5%), and full fat (3.0%) UHT milks. The milk samples were inoculated with L. monocytogenes at the level of approximately 2.60, 4.76, and 6.45 log CFU ml−1, and then treated with various concentrations (400, 800, 1600, or 2500 AU ml−1) of lactococcin BZ, enterocin KP, or their combination (1:1). Lactococcin BZ at 400–2500 AU ml−1 level displayed strong antilisterial activity, and decreased the viable cell numbers of L. monocytogenes to an undetectable level in all types of milk samples during the entire storage periods at 4 °C or 20 °C. Enterocin KP also had a high antilisterial effect, but it decreased as both the fat content of milk and inoculation amount of L. monocytogenes increased.

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The paper describes efficient methods to post-process results from the finite element analysis. Amount of data produced by the complex analysis is enormous. However, computer performance and memory are limited and commonly-used software tools do not provide ways to post-process data easily. Therefore, some sort of simplification of data has to be used to lower memory consumption and accelerate data loading. This article describes a procedure that replaces discrete values with a set of continuous functions. Each approximation function can be represented by a small number of parameters that are able to describe the character of resulting data closely enough.

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Authors: L. Szalóki-Dorkó, A. Nagy, N. Adányi and R. Tömösközi-Farkas
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Part II of the study deals with changes of support structures interpreted among building constructions. We primarily link structural changes to the application of new materials and new approaches. Two areas are dealt with in this present study. One is the development and change of vaults, the other is changes of framework of building in case of applying new materials that are only partly suitable for taking bending and tensile stress.

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Authors: B. Csehi, E. Szerdahelyi, K. Pásztor-Huszár, B. Salamon, A. Tóth, I. Zeke, G. Jónás and L. Friedrich

In the experiments pork loin and beef sirloin were treated by pressures of 100 to 600 MPa by 100 MPa steps for 5 min. Colour changes of samples and the changes of proteins were investigated. The latter were examined with isoelectric focusing and SDS polyacrylamide gel electrophoresis. We found that myoglobin behaved completely differently in case of the two different species. Myoglobin has mostly lost its native state at 300 MPa pressure in case of pork, but the beef myoglobin could remain native even up to 500 MPa. The treatment at 300 MPa or higher pressure values caused almost complete aggregation and denaturation in case of pork and beef proteins. The results of SDS-PAGE and the colour measurement confirmed this finding.

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The issue of urban development requires strategic thinking. It includes self-sustainable mechanisms, strengthening self-organization and financing of the cities, collectively. Nowadays cities face challenges in all three domains that necessitate strategic thinking on the local, national and EU levels alike.

This strategic thinking has to answer the questions concerning how is it possible for a city to implement developments that might have-long term and sustainable results for the inhabitants. What is the underlying logic to define, plan, implement and sustain city policy objectives? The search for the answer provides multiple evaluation methods. One of these logical frameworks is measuring the success of cities in the context of development/s related to a specific event.

The success of cities is researched and measured with numerous tools and methods. Analyses in this field are becoming more common, not only on a yearly basis but even more often.

The City Success Index — interpreted and presented in the current study — puts larger emphasis on involving and evaluating the so-called human factors, meanwhile creates a logical frame, which - due to the portfolio-analysis method’s flexibility — is more ‘customizable’ for a city that would like to organize a world-class or international events with strong impact, and reveals the possible opportunities and threats. The methodology is able to contribute to strategy planning or for the evaluation of the event. The applied economic model as the frame of research in the approach is new, while the utilization of the result-zone developing might offer help in decision processes of several other public policy domains.

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In this study, the traffic flow of morning peak hour is analyzed in residential areas using dynamic traffic assignment method. A comprehensive analysis of the traffic assignment was performed in six different network topologies. The main goals were to compare different road networks and to identify significant similarities and differences of these patterns. By comparing results, a highly detailed picture of the differences crystallized between travel time, velocity and ratio of used routes.

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The European standards for asphalt mixture testing are mainly focused on empirical parameters of asphalt mixtures. On the other hand, functional parameters (e.g. fatigue, stiffness) of asphalt mixtures describe real behavior of the material in-situ. These parameters are used for design of road construction according to the Slovak design method where the elasticity modulus is used instead of the complex modulus. The problem is that no standard for elasticity modulus measurement exists in the collection of the European standards. In this study complex modulus measurement was performed according to the European standard, and for comparison elasticity modulus measurement was also done according to the Australian standard.

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Wind velocity profile varies in the boundary layer according to a complex pattern that depends hugely on the surface roughness and local Reynolds number. The presence of a macroscopic obstacle on the ground surface modifies considerably the flow characteristics of wind speed profile. In this study, the effect on wind speed resulting from local circulatory motion induced by the existence of an obstacle is analyzed in stationary conditions under the assumption of two-dimensional approximation of the problem. Computational fluid dynamics is used to solve the turbulent air flow equations that consist of Navier–Stokes equations coupled to a K-ε turbulence model. A bounded domain having a rectangular form was introduced in order to schematize the atmospheric region containing the obstacle and wind turbine. The boundary conditions at ground surface were fixed by applying a modified wall law. The other boundary conditions included a logarithmic velocity profile at the input, a uniform speed applied on the upper edge of the rectangular domain and a uniform pressure in the outlet area. To solve the obtained equations, Comsol Multiphysics software package was used. The obtained results have shown that the presence of an obstacle has a huge effect on the wind profile pattern and affects largely the extractable power from wind by the wind turbine system.

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The aim of the research is to reveal the most important influencing factors that lead to consumers’ acceptance of personalised nutrition based on genetic testing. A nationwide representative questionnaire-based consumer survey was carried out involving 500 people in Hungary in 2014. The results show that consumers are divided over the new technology. Only 27.0% of the respondents have a positive attitude toward the new possibility, and they would be glad to use this new service in order to stay healthy. The rate of those who would have a genetic test because they want to follow a diet tailored to their needs is very low (16.0%). Our result suggested that the most important factors in consumer preference on personalised nutrition are positive health message and perceived risk/benefits, gender, and educational level. The most important factors regarding the attitude toward genetic testing are easy usage, benefits, the agreement among experts, and educational level.

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Dietary fibres (DFs) are essential components of the balanced diet. Even though the adequate level of their consumption can be ensured from several natural (e.g. fruit, vegetables, legumes) and ‘artificial’ sources (e.g. functional foods), the consumed levels are below the recommendations. To analyse the Hungarian and Romanian consumers’ knowledge level, their perceptions of the health benefits associated with fibre, as well as the recognition of the potential information sources, a survey questionnaire was conducted with the total of 713 consumers. Results showed that the level of knowledge about DFs was not adequate. Internet was found to be widely used and identified as one of the most appropriate information sources to encourage the consumption of DF. It was a favourable result that three-quarter of the respondents was interested in the topic of healthy food consumption; however, just less than half of them took into consideration the label information during their shopping decisions. To increase the consumption of DF and to support the responsibility and conscious consumer decisions steps must to be done (e.g. education of children, pointing out of the sources). For this purpose, modern information technology and communication channels fitting to the consumers’ cultural and personal particularities can be utilized.

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The forty years of intensive mine dewatering in the Transdanubian Range contributed to getting high quality and large amount of data about the karstified aquifers, which could not be gained in any other way. In addition to providing the claimed depression to the safety mining under the original karst water level, the scientific investigation of the processes was emphasized. Although the mines were abandoned the data sets could be a great base of additional investigation about the karstified aquifers. This paper presents the evaluation of dewatering data as pumping test data by using many methods.

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The aim of the present study was to evaluate the effect of high hydrostatic pressure (HHP) processing (at 450 or 600 MPa for 300 s) on microbial quality as well as on organoleptic properties of fish salad with mayonnaise during 26 days of storage at 5 and 10 °C. The salad contained diced smoked trout fish, mayonnaise, and different kinds of spices. These freshly made salads usually have only a couple of days of shelf life. The HHP treatment basically did not affect the physical and organoleptic characteristics of the fish salad with mayonnaise. At both storage temperatures, the HHP treated samples showed enhanced safety and increased shelf-life up to 3 weeks.

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The role of light-emitting diode lamps and radio frequency lighting controls is to reduce the energy consumption. The increase of lighting network complexity determines the increase of EMC noise emission. Being familiar with measurement systems is important for making correct measurement and for understanding the results of the measurement. Correct interpretation of measurement results is the first step in choosing the best suppression method. The suppression method depends on the common mode and the differential mode of noise type and on the frequency of signal noise.

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This paper deals with the most recent technology in wireless communication which is massive multiple input multiple output system. The paper studies the performance of massive multiple input multiple output uplink system over Rayleigh fading channel. The performance is measured in terms of spectral and energy efficiency using three schemes of linear detection, maximum-ratio-combining, zero forcing receiver, and minimum mean-square error receiver. The simulation results show that the spectral and energy efficiency increases with increasing the number of base station antennas. Also, the spectral and energy efficiency with minimum mean-square error receiver is better than that withzero forcing receiver, and the latter is better than that with maximum-ratio-combining. Furthermore, the energy efficiency decreases with increasing the spectral efficiency.

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This research presents a field-circuit coupled parallel finite element model of a switched reluctance motor embedded in a simple closed loop control system. The parallel numerical model is based on the Schur-complement method coupled with an iterative solver. The used control system is the rotor position based control, which is applied to the FEM model. The results and parallel performance of the voltage driven finite element model are compared with the results from the current driven model. Moreover, the results of the start-up of the loaded motor show why the model accuracy is important in the control loop.

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Author: Péter Iványi
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Milk gangliosides have gained considerable attention because they participate in diverse biological processes, including neural development, pathogen binding, and activation of the immune system. The aim of this study was to determine the concentrations of total gangliosides in dairy products and to determine whether there is a significant difference in comparison to concentration of gangliosides in cow’s milk. The concentration of total gangliosides in dairy products was significantly higher than concentration in cow’s milk. The highest concentration of gangliosides was determined in yogurt with 3.2% of milk fat.

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Authors: I. Mohammadpour, R. Ahmadkhaniha, M. Zare Jeddi and N. Rastkari

The safe use of recycled paper and board material for food packaging applications is a major area of investigations. Therefore, the aim of current study was to evaluate the amount of heavy metals in recycled paper pastry packages and measurement of migration over the time into pastries.

In this study, the presence of heavy metals in common confectionery packaging and effects of storage time and kind of pastry on the migration are investigated.

The results of the study indicate that harmful metals such as Pb are detected at high concentrations in most of the recycled boxes that are used for pastry packaging, and heavy metals could migrate from the recycled packages into food during usage.

It seems that the procedure of preparing recycled paperboard for food packaging should be reconsidered.

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Considering the below rated power region of a variable speed wind turbine approximated by a single-degree-of-freedom system, a hybrid adaptive controller based on sliding mode control and radial basis functions neural networks was proposed. Stability of this controller was assessed by using Lyapunov approach. The control algorithm was implemented by means of Matlab/Simulink software package. Comparison with other reference controllers has proven that the proposed controller is relevant as it improves performance in terms of produced electrical energy by the wind turbine system while reducing the amplitude and fluctuations of mechanical loads.

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The extractable (ASTA) colour retention of four different milled spice paprikas was evaluated at 10, 20, 35, 50, and 60 °C storage temperature. The ASTA colour stability during long-term storage period strongly depended on the temperature, primary handling and drying of the fresh crop, and the applied production technology. The cooled (10 °C) or temperature-controlled (20 °C) conditions appeared to be a reasonable solution to preserve the quality of paprika powder. The kinetics study on the temperature dependence of ASTA colour loss estimated the apparent reaction order, rate constants, predicted half-life times and activation energy. The Q10 approach and shelf life-plot resulted in useful data, which can be suitable for quick and economical evaluation of further spice paprika products.

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Authors: L. Danner, N. de Antoni, A. Gere, L. Sipos, S. Kovács and K. Dürrschmid

This study investigates the relationship between gazing behaviour and choice decision in multialternative forced choice tasks, focusing on the consistency across different food product groups including apple, beer, bread, chocolate, instant soup, salad, sausage, and soft drink. Each choice task consisted of pictures of four alternatives, similar in familiarity and liking ratings, of the corresponding product group. A Tobii T60 eye-tracker was used to present the stimuli and to analyse the gazing behaviour of 59 participants during decision-making.

The results showed strong correlations between choice and gazing behaviour, in forms of more fixation counts, longer total dwell duration, and more dwell counts on the chosen alternative. No correlations for first fixation, time to first fixation, and first fixation duration were observed. These results were consistent across the eight tested product groups.

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Authors: Michaela Červeňanská, Dana Baroková and Andrej Šoltész

The water sources located on the inland islands on the left side of the Danube River as well as water sources located on the right bank of the Danube River in the Pečniansky forest have an irreplaceable function in terms of supplying the population in Bratislava with drinking water. There are 80 wells in these mentioned areas operated by the Bratislava Water Company. In order to maintain the actual functions of the water resources, it is therefore necessary to assess the impact of the proposed construction of the multi-purposed structure ‘Hydraulic structure Bratislava — Pečniansky forest’ on these water sources.

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A uniform track condition assessment model, which is based on both visual inspection and automatic under load track geometry measuring system, is needed to reduce maintenance cost and increase safety and ride comfort for passengers. A tramway track condition assessment model as well as a geographical information system are worked out by the Author (implementation in progress) for Budapest tram lines to detect and predict rail defects and plan the effective maintenance work. The developing method determines the track condition on the basis of visual inspection and in-service vehicle’s wheels-mounted accelerometers.

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Authors: Alina-Maria Nariţa, Vlad Gurza, Răzvan Opriţa, Alexandra Keller, Iasmina Apostol, Marius Moşoarcă and Cătălina Bocan

Extreme actions represent a high risk for buildings belonging to historic urban areas and archaeological sites. Because of the conformation of the buildings, the low quality of used materials and the current state of conservation, these buildings tend to be very vulnerable to horizontal forces generated during earthquakes and terrorist attacks.

This article analyses the mechanisms caused by extreme actions that are capable to generate a considerable degree of damage or even collapse of international cultural heritage buildings from historic urban centers and sites.

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Several nonlinear simulations of concrete and reinforced concrete slabs are performed using a layered model. Two Drucker-Prager criteria are employed to form a concrete plasticity model that is used for simulating the plastic yielding of layers. Moreover, an interaction with elastic Winkler-Pasternak subsoil model is considered for the case of a reinforced concrete foundation slab that is subjected to a concentrated loading force. All computations are done by the SIFEL solver using finite element method.

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The Selice water structure is situated on the lower Váh River. Within the frame of its preparation there was no hydraulic research conducted on the design of the layout of the structure and the nautical conditions for vessels approaching the water structure. The work deals with an evaluation of the parameters of the water flow and their impact on a vessel at the entrance to the approaches to the lock chamber in terms of navigational safety. Different scenarios have interpreted the passing of flows over the Selice water structure. Based on interpretations of the simulations, recommendations for the optimal operation of the water structure have been proposed with regard to navigational safety.

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This study was based on the production of an alcoholic beverage from apple using laboratory pervaporation equipment. Hungarian fruit brandy is called pálinka, which can be made by pot distiller or multistage distiller made of copper. In case of traditional pot still distillation the final product is gained from two separate distillations. Pervaporation is an energy efficient membrane process for separating liquid mixtures. Application of pervaporation to separate the product of the initial distillation leads to lower energy consumption than using double-distillation process. The aim of our work was to develop an alternative technology for the production of pálinka that integrates distillation and pervaporation.

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Winery wastewater treatment plants generally face severe nutrient deficiency, and therefore conventional technologies and supplementary nutrient dosing strategies may fail. The purpose of the paper is to show how traditional way of dosing N-source for marginal availability to nutrient deficient influents results in poorly settling activated sludge regardless of the application of aerated or non-aerated selectors. External N-source calculated for marginal availability resulted in nutrient deficiency due to the relatively high yield experienced (0.7 g biomass COD/g substrate COD). In the fully aerated system with overall N-deficiency, rapidly increasing overproduction of extracellular polysaccharide was experienced, leading to SVI (Sludge Volume Index) values up to 600 cm3 g−1. In the system with the non-aerated selector, initial nutrient deficiency could only be detected in the second reactor. Since neither overgrowth of floc-forming GAOs (Glycogen Accumulating Organisms) nor denitrification could be experienced, the non-aerated reactor operated as low-DO (Dissolved Oxygen) basin, attributing to the drastic overgrowth of filamentous bacteria leading to SVI values >1000 cm3 g−1. Since dosing external N-source for marginal availability is likely to cause severe biomass separability problems in activated sludge winery wastewater treatment, either pronounced N-overdosing and pre-denitrification or severe nutrient deficiency and GAO cultivation can rather be recommended.

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Authors: A. Mühlhansová, N. Zhexenbay, A. Kozybayev, Š. Horáčková, K. Solichová and M. Plocková

Conventional quantification of L. helveticus, in presence of other lactobacilli species, using classical plate method employing low selective media is very inaccurate. Determination of L. helveticus using quantitative PCR (qPCR) was performed in six artisanal Kazakh soft cheeses made from cow’s milk or from a mixture of cow’s and goat’s milk. L. helveticus was quantified by species-specific qPCR, monitoring the presence of genes encoding for peptidoglycan hydrolases. Quantification of L. helveticus based on qPCR ranged from 2.6×106 to 4.1×108 CFU·g−1 according to the type of the cheese. The microflora of cheese consisted of a mixture of starter and non-starter lactic acid bacteria.

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Aircraft manufacturing industry has developed dynamically in the last decades. Reinforced polymers have become the most dominant raw materials, while the recycling rate of the generated industrial waste has also increased. The greatest aircraft manufacturers have integrated environmental protection in their production process, while defining clear environmental goals for the future. In this study, we have analyzed the environmental considerations of the aircraft manufacturing industry through the examples of Boeing and Airbus companies. Our goal was to define the possible environmental impacts of the aircraft industry, focusing on raw material usage and waste recycling.

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A new calculation method for deriving easy-to-use equations for the simplified calculation of non-repeating thermal bridges is presented and tested on several constructional variants of a common Central-Europe building type. Through the identification the main parameters affecting the difference between the one- and multidimensional heat transfer coefficients of facades their number is reducible. The method’s accuracy compares favorably to current calculations. A new formulation is introduced for the calculation of the total heat transfer coefficient of the external thermal envelope incorporating the proposed simplified thermal bridge calculation method and the window’s in-situ heat transfer coefficients.

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This paper deals with the most recent technology in wireless communication which is massive multiple input multiple output system. The paper studies the performance of massive multiple input multiple output uplink system over Rayleigh fading channel. The performance is measured in terms of spectral and energy efficiency using three schemes of linear detection, maximum-ratio-combining, zero forcing receiver, and minimum mean-square error receiver. The simulation results show that the spectral and energy efficiency increases with increasing the number of base station antennas. Also, the spectral and energy efficiency with minimum mean-square error receiver is better than that withzero forcing receiver, and the latter is better than that with maximum-ratio-combining. Furthermore, the energy efficiency decreases with increasing the spectral efficiency.

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Driven by updated building energy codes and green building initiatives across the world, vacuum insulation panel, also known as VIP, has become a desired insulation product for building envelope constructions. VIP has initial center-of-panel thermal conductivity of 0.004 W/mK or lower, and integration of VIP in building envelopes can reduce CO2 emissions and contribute towards ‘net-zero’ or ‘near-net-zero’ building constructions. Although VIPs have been applied in real-world constructions across the world, primarily in Asia, Europe and North America, it is still a novel building product under investigation. This overview paper is a summary of fundamentals, constituents, constructions and performances of VIPs. The paper shows there exists many advantages and challenges associated with the integration of VIPs in building envelope constructions. The speed at which VIPs will be integrated in building envelope construction in the coming years remains unclear; nevertheless, it is evident that vacuum technology is the promising way forward for sustainable building envelope constructions in the 21st century.

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The aim of the study was to estimate how selected physical and chemical characteristics of defrosted modified atmosphere packaged (MAP) not deveined shrimp (green shrimp with head) (Litopenaeus vannamei) meat are affected by two of the most often used culinary processing (cooking and frying). The experiment was carried out with 61 green shrimps with head (the country of origin: Ecuador; MAP 30% CO2/70% N2; stored 8 days at 0 °C to +2 °C) samples and evaluation of weight loss, pH, total volatile basic nitrogen (TVBN), and trimethylamine (TMA) contents. Weight losses and pH of examined shrimp samples after cooking and frying were significantly (P<0.05) lower, while same fluctuations in TVBN and TMA contents were noticed between culinary treatments (cooking, frying) as between different parts of shrimp tails. Significant correlations (P<0.05) were found between pH values and freshness indicators (TVBN, TMA-N), emphasizing different ongoing post-mortem metabolic and degradation processes in different parts of edible shrimp (Litopenaeus vannamei) parts (peeled tail).

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The variational principle, which allows the deduction of the basic equation system of continuum mechanics from the local form of Gyarmati’s integral principle is presented in this paper. Following the approach of irreversible thermodynamics, the principle the kinetic energy is described like the fundamental equation of thermodynamics as the internal energy change, namely intensive quantity multiplied by the changing of extensive quantity. As the internal energy is objective so that is an independent quantity from the coordinate system, this description to the internal energy can be done. However, the kinetic energy is coordinate-dependent quantity. To resolve this contradiction the stress tensor can be divided into elastic and dissipative stress components by using the laws of thermodynamics.

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The paper has been presented at the ceremonial lecture held on 29 April 2016 for the nomination of the main lecture hall in the Science Building after the genius professor Zoltan Bachman belonged to the Faculty of Engineering and Information Technology, University of Pecs.

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This paper will present a concept to use matermaterial thin film deposited on a window glass to absorb tuned solar spectrum for anti-frost/anti-fog and energy-saving in cold weather, meanwhile the luminous transmittance of the windows can be maintained. In warmer weather, the opposite side of a rotatable window can be turned to face the sunlight to reflect the sunlight away with the perfect mirror function of the base ground layer of the metamaterial thin film. By adjusting base ground coating structure, perfect or non-perfect mirror can be formed for natural solar reflection or transmittance. The metal-dielectric-metal nano-scale metamaterial structures with periodic metal-dielectric interfaces, when shined with light, acquire surface plasmons thus trapping light at subwavelength scales. When the metamaterial film is coated on the outside of a glass window, it will lead to efficient solar radiation absorption, which can be used for anti-frost/anti-fog and energy-saving windows of transportation vehicles and modern buildings. The total thickness of the so-called metamaterial solar absorber thin film is a few tens of nanometer and its absorption band is broad, tunable and insensitive to the angle of incidence.