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Authors: J. Pokorná, P. R. Venskutonis, V. Kraujalyte, P. Kraujalis, P. Dvořák, B. Tremlová, V. Kopřiva and M. Ošťádalová

Coffee beans contain a large amount of antioxidants, which are subjected to various changes during roasting. In this study, antioxidant potential of raw and roasted to different degree (light, medium, dark) C. arabica and C. robusta coffee beans was evaluated by the four antioxidant assay methods, TPC, FRAP, TEAC, and DPPH˙.

The obtained results revealed significant differences between the coffee types, roasting degree, and antioxidant activity assessment methods. FRAP and TPC appeared to be the most appropriate methods for revealing the differences in antioxidant potential of different coffee types and the effects of roasting. The results obtained by these methods were in good correlation. ABTS and DPPH? methods are not enough sensitive for the determination of roasting degrees.

In general, based on statistical data evaluation, antioxidant activity is more dependent on the coffee type than on the degree of roasting, however, the selection of analytical method may also be significant.

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Plants exposure to environmental sources of common inorganic anions (chloride, nitrate, phosphate, and sulphate) is discussed. Various commercial tea products were examined for the content of water soluble anions by the use of sample preparation procedure corresponding to the conditions generally applied for the preparation of tea infusions (2 g of tea, 5 min brewing time, 250 ml final volume) widely consumed by humans. Suppressed ion chromatography (IC) (Metrohm Metrosep A Supp 5 (150 mm × 4 mm) column) with conductometric detection was used for the determination. The IC technique allows isolation of the signals of particular anions and their detection (DLs of 0.012 (Cl), 0.019 (NO3 ), 0.047 (PO 4 3–), and 0.011 (SO 4 2–) mg l−1) within 15 min.

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A modified QuEChERS method was developed and validated for determination of pesticide multi-residues in green tea by liquid chromatography tandem mass spectrometry. Lead acetate was first time used together with primary secondary amine and graphite carbon black to eliminate tannin, caffeine, and other pigments in tea and thus reduced the matrix effects. The method was compared to the original QuEChERS method as well as A.O.A.C. QuEChERS method. For accurate quantification, the matrix matched calibration technique was used. The method showed good performance in the concentration range from 0.01 to 1 mg kg–1. All pesticides could be quantified at and lower than 0.01 mg kg–1. Recoveries were from 70 to 120% and repeatabilities were <15% RSD depending on the compounds.

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Authors: J. Bystricka, J. Musilova, J. Tomas, J. Noskovic, E. Dadákova and P. Kavalcova

Onion bulbs (Allium cepa L.) are good sources of flavonoids. The aim of this study was to analyse the changes in dynamics of quercetin formation in three varieties of onions (white, yellow, and red) during the vegetation period. Quercetin content was determined after acid hydrolysis (1.2 M HCl in 50% aqueous methanol) by high-performance liquid chromatography (HPLC). The content of total phenolics was determined using Folin-Ciocalteu reagent (FCR) according to LACHMAN and co-workers (2003). The content of polyphenols in onion ranged from 2893 to 6052 mg kg–1 and the content of quercetin ranged from 52.44 to 280.72 mg kg–1 in fresh matter. The highest content of polyphenols and quercetin was found in the red variety. According to statistical analysis the dynamic of quercetin formation in all cultivars had statistically moderate (P<0.05) increasing tendency. Increasing content of polyphenols was accompanied with slight increase of quercetin, but the differences remained insignificant (P<0.05).

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Authors: J. Tangtua, C. Techapun, R. Pratanaphon, A. Kuntiya, V. Sanguanchaipaiwong, T. Chaiyaso, P. Hanmuangjai, P. Seesuriyachan, N. Leksawasdi and N. Leksawasdi

Candida tropicalis TISTR 5350 was used in the comparison of seven concentration levels of silver nanoparticles (0, 5, 10, 15, 20, 25, and 30 μg ml–1) for cell disruption methods. The optimized cell disruption strategy was selected based on the optimal protein yield and biological activity. The maximum volumetric and specific pyruvate decarboxylase (PDC, EC 4.1.1.1) activities (0.53±0.05 U ml–1 and 0.17±0.02 U mg–1 protein, respectively) were observed at 15 μg ml–1 silver nanoparticles. The silver nanoparticle concentration level of 15 μg ml–1 was investigated further by comparing the reaction mixtures at different time intervals of 0, 1, 2, 3, 4, 5, and 6 min. The result showed that the highest specific PDC activity of 0.39±0.01 U mg–1 protein was obtained from mixing for 3 min. This was not significantly different (P≤0.05) from other mixing time intervals.

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This study was aimed at evaluating the efficacy of different mineral separation procedures to validate the EN1788 (2001) European Union standard protocol for better identification of irradiated fish and shellfish. The silicate minerals were isolated with physical density separation method from two types of non-irradiated freeze-dried fish and shellfish that included Pacific saury (Cololabis saira), mackerel (Scomber japonicus), shrimp (Penaeidae metapenaeus), and mussel (Mytilus coruscus). Radiation-specific thermoluminescence (TL) peaks (glow curve 1) were observed between 150–250 °C. The peaks are typical for the irradiated food; despite the samples being not irradiated. Apparently it showed that the isolated minerals were contaminated with organic materials such as bone, etc. Acid-hydrolysis digestion was employed to remove the possible contaminants. The minerals obtained through alternative pre-treatment showed no TL curves in radiation specific temperature range. Moreover, acid hydrolysis extraction resulted in producing higher mineral yields and lower background luminescence. Results were also confirmed by calculating TL ratios (glow curve 1/glow curve 2) to confirm the irradiation history of samples. Furthermore, different time and temperature treatments on TL intensity of irradiated standard quartz (SiO2) minerals showed that the acid-hydrolysis can be adjusted to 50 °C and 3 h for better luminescence determinations.

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Disorders induced by cereal proteins (e.g. wheat allergy, celiac disease) are widespread in human population. Since their only effective treatment is the avoidance of the problematic proteins, patients have to be familiar with the composition of food products. For checking special foods produced for them, proper analytical methods are necessary. At the moment, in gluten analysis there are no reference methods and reference materials which model real food matrices. During the production and experimental utilisation of our previously developed reference material candidate, numerous questions emerged. As our model product is a real food matrix, interactions can be present between gluten proteins and other macro and micro components. Fat content of the baked cookies is almost 20%, which might affect the results of ELISA measurements. The detectable gluten content is significantly increasing after the defatting procedure, as a pre-treatment of samples. Moreover, baking is a common food processing step that might modify the structure of gluten proteins leading to denaturation and aggregation. In the soluble protein fraction the amount of low molecular weight proteins increases, while that of high molecular weight proteins decreases during the baking procedure.

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Oysters are filter-feeding bivalve molluscs that are associated with several foodborne illnesses, because they accumulate biotic and abiotic contaminants dispersed in the water. The state of Paraná in southern Brazil is distinguished by a high consumption of oysters, typically eaten raw, and this habit may present a risk to consumer health if the product is contaminated with pathogenic bacteria. This study intends to evaluate the microbiological quality of oysters produced and traded in Paraná, directly examining the localities of cultivation and trading of the product. The major sites for the trading of oysters in the state were identified and 52 dozen oysters (624 animals) were collected from these places, between April and December, 2013. The samples were subjected to analyses for total coliforms, Escherichia coli, Staphylococcus aureus, and Salmonella spp. No samples had results of microbial contamination above the limits established by Brazilian legislation. This study indicated that the microbiological quality of the oysters produced and traded in the state of Paraná is acceptable.

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Authors: J. A. Grahovac, Z. Z. Rončević, I. Ž. Tadijan, A. I. Jokić and J. M. Dodić

Bacillus subtilis is one of the most important producers of diverse antimicrobial compounds. This bacterium grows and produces antibiotics on different substrates. The increase of the antibiotics yield can be achieved by changing the conditions of cultivation and the composition of the culture media. In this study, response surface methodology was used for optimization of glycerol, sodium nitrite, and phosphate content in media for production of antibiotics effective against Staphylococcus aureus. As biosynthesis strain Bacillus subtilis ATCC 6633 was used. The developed model predicts that the maximum inhibition zone radius (38.08 mm) against Staphylococcus aureus and minimal amount of residual nutrients (glycerol 1.75 g l−1, nitrogen 0.21 g l−1, phosphorus 0.18 g l−1) are achieved, when the initial content of glycerol, sodium nitrite, and phosphate are 49.99 g l−1, 1.00 g l−1, and 5.00 g l−1, respectively.

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The refinement of unsaturated fatty acids (UFA) from Hippophae rhamnoides L. seed oil was carried out by molecular distillation (MD) using response surface methodology (RSM). A central composite rotate design was used in order to optimize the experimental parameters: distilling temperature and feed flow. The optimal MD conditions were determined and the quadratic response surfaces were drawn from the mathematical models. The results suggested that the distilling temperature and feed flow significantly affected both the UFA content and oil yield in the two models. The optimum conditions for refining UFA were: distilling temperature 107.5 °C and feed flow 1 ml min−1. Optimal values predicted by RSM for the UFA content and oil yield were 82.38% and 62.59%, respectively. Close agreement between experimental and predicted values was obtained.

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Authors: N. Topic Popovic, A. Benussi Skukan, P. Dzidara, I. Strunjak-Perovic, S. Kepec, J. Barisic and R. Coz-Rakovac

Listeria monocytogenes is a bacterium widespread in the environment, which has a capacity to survive and grow under various conditions. The bacterial growth results from interactions when subjected to various temperatures, pH levels, and NaCl concentrations were examined by measurements and predictive modelling. Good correlation across the range of growth conditions was shown among observed and predicted growth values, having similar trends and minimal deflections for pH levels 5.0 and 6.0. The growth condition in the 8% NaCl concentration (pH 7.0, temperature 4 °C) resulted with a growth curve of 1 log interval greater than the fitted curve for all the measurements. In all of the cases, there were consistent increases in the rates and decreases in the lag time when the growth temperature increased. Higher incubation temperatures provided higher growth rates as 30 °C and 35 °C yielded double increase of the fitted rate. Fitted and measured growth rates for salinity conditions were significantly different (P<0.05). Comparison of doubling times showed good compatibility, particularly at lower temperatures. Critical use of a model is suggested, although it may enable microbiologists to limit the need of challenge tests and to make rapid and realistic prediction of the growth of L. monocytogenes under conditions relevant to a range of aquatic and other products examined.

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The ability of Kocuria varians to grow and produce protease when utilizing various local wastes was studied. Impact of cultivation pH on growth and enzyme production was also evaluated. Cassava waste combined with bambara nut waste (1:1) gave the best protease yield. Maximum enzyme production was attained when production medium was adjusted to pH 9. Highest protease concentration in the culture fluid was recorded at 20 h during the exponential phase of growth. The enzyme was optimally active and stable at 80 °C. Optimum pH for protease activity was at 11 with optimal stability at the alkaline range (pH 7–11) after incubation for 1 h. The enzyme was inhibited by EDTA, Hg2+, and Zn2+, but not by Pb2+, and was slightly stimulated by Cu2+. The properties of this protease make it a promising candidate for further studies and possible applications in processes involving extreme conditions of pH and temperature.

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Authors: Zs. Hajdu, L. Lorántfy, N. Jedlinszki, K. Boros, J. Hohmann and D. Csupor

The radish-like hypocotyls of Maca (Lepidium meyenii Walp., Brassicaceae) are widely consumed as common vegetable in the Andean highlands. It is considered as healthy food, rich in carbohydrates and protein, a herbal medicine with a general invigorating reputation and fertility and sexual performance enhancer. The latter is the most popular contemporary application of the plant in Europe. The number and variety of industrial products on the market is increasing. Here we report the development of a simple and reliable analytical protocol for the qualitative and quantitative analysis of maca content of preparations and for the detection of synthetic phosphodiesterase inhibitors. Fourteen products were analysed by the method based on TLC and HPLC-DAD analysis developed by us. Our experiments revealed that beside good-quality products, the majority of the multicomponent preparations did not contain the declared herbal component or the quantity of the measured macamide was very low. Furthermore, one preparation is adulterated with a synthetic phosphodiesterase inhibitor. The presented method is suitable for quality control of L. meyenii products.

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Alteration of physical and chemical qualities of pressurized and heat treated Nam Prig Nhum (Thai-green-chili paste) was thoroughly assessed upon storage for eight weeks. During storage, colour L, –a*, and b* parameters of pressurized Nam Prig Nhum displayed comparatively low changes. The enzyme activities of peroxidase, lipoxygenase, and polyphenol-oxidase nearly fell by half during storage. Peroxidase was the most resistant to pressure followed by lipoxygenase and polyphenol-oxidase. For pungent components, all capsaicinoids in Nam Prig Nhum underwent alteration by the thermal processes as well as by acidic and oxidative degradation during storage. However, higher amount of capsaicinoids were retained in pressurized than in heat treated products.

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The HACCP system is a food safety approach, which prevents hazards before they happen. With this survey we aimed to determine the HACCP knowledge of staff working in kitchens of food businesses in Istanbul and correlate the results with some demographic characteristics in order to evaluate HACCP awareness in the foodservice sector in Istanbul. A self-administrable questionnaire was developed in order to evaluate the knowledge of food handlers in all stages of kitchen work. The questionnaire consisted of a first set of 9 demographic questions followed by 12 items related to HACCP system application. According to data obtained from this study, food handlers’ HACCP knowledge increases parallel with age, education level, and time spent in the sector and seniority. In addition, in order to increase the knowledge and awareness of HACCP, training has been found to be important.

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This study aimed to evaluate the survivability of lactobacilli cells encapsulated in calcium alginate beads coated with methacrylic acid copolymers (MAc) in high acidic foods (orange juice and mayonnaise). Lactobacilli survived well at low temperature (4 °C) for 6 wk in orange juice, 4 wk in heat-treated orange juice, 12 wk in mayonnaise, and 8 wk in heat-treated mayonnaise (P<0.05), without affecting the acidity of orange juice and mayonnaise during storage. FTIR spectra showed that the characteristic peaks of calcium alginate and MAc were not altered, designating no high affinity interaction between calcium alginate and MAc. DSC of MAc-coated alginate beads indicated an increased in melting temperature, demonstrating improvement in molecular orientation in the MAc-coated alginate beads compared to the control. Sensory evaluation revealed that panellists could detect the presence of MAc-coated alginate beads, leading to a lower acceptance score.

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The present study was designed to investigate the antioxidant and antimicrobial activities of pressurized liquid extracts from Haberlea rhodopensis Friv. The total phenolic content was performed using the Folin-Ciocalteu phenol reagent. To determine the antioxidant activities of the extracts, several complementary tests were used: ABTS and DPPH radical scavenging activities, oxygen radical absorbance capacity, and ferric-reducing antioxidant power assay. The phenolic concentration was 15.98±0.09 and 9.42±0.06 mg GAE g−1 DW for 70 and 85% ethanol extracts, respectively. Of all the performed methods, the highest antioxidant activity values were measured by the ORAC assay — 224.6±6.6 and 154.0±9.9 μM TE g−1 DW for 70 and 85% ethanol extracts, respectively. Results also showed that both extracts exhibited very weak antimicrobial activity against the examined microorganisms. However, the 70% ethanol extract possessed higher inhibition ability, which correlated with higher total phenolic content and antioxidant activity.

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An integrated hydrological model has been applied for small rural-urban catchments at the Tisza-Maros confluence using the WateRisk integrated hydrological model system. The aim of the hydrological simulations was to identify the role that the relief plays in the runoff generation process, and to highlight the relationship between the precipitation, runoff and the depression’s water storage of the relief. The overall aim is to support the description of contaminant (phosphorus) transport processes with knowledge about the rainfall-runoff-storage relationship, described with the complex deterministic hydrodynamic model system. To support this aim the rainfall-runoff and the one-dimensional flow routing modules have been used in the model. Results suggest that the depletion of the surface depressions water storage capacity is a non-linear saturation type function of the amount of rainfall falling on the surface. Manning n values of the drainage channel system might also have strong influence on runoff dynamics.

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The head-line of the article is advisability to combine information technologies and principles of lean production in activity of machine building enterprises to ensure efficiency improvement. The article reviews enterprise resource planning systems and the lean production conceptions: their development and construction basis, main advantages and weaknesses.

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The topic of the paper is to investigate procedure to determine bending moment resistance of girders with corrugated webs. Concepts provided by Eurocode EN 1993-1-5 and EN 1999-1-1 are different and not very clear for practical design. To clarify determination of elastic critical bending moment, a finite element model of simply supported beam under uniform bending moment has been created. Positive influence of web corrugation on bending stiffness has been expressed through the improved factor c1 used for flat girders. Results of bending moment resistance have been compared to show the difference between the concepts and to provide more appropriate assessment.

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The innovative suggestion of this work is the usage of bended composite arms instead of complicated steel arms with hinges. The basic idea of the new structure is very simple, which is one of the best advantages of this structure. The bended arms could pre-stress the membrane surface and in the same time the membrane bends the arms, this interaction produces a harmonic structure with effective properties. The hinges can be avoided, because the open position of the umbrella created by the bend of the arms. Nowadays existing retractable funnel umbrellas are highly advanced, which is a result of decades of development, but the openingclosing process is quite complicated with very complex kinematics and complicated steel structure. Using the bended supporting elements a new structure for the retractable funnel umbrellas could be developed, which provides better structural behavior and simpler motion during the opening-closing process. The goal of this work is a development of a new type of convertible umbrella with innovative structure, which opens up new perspectives concerning the design of umbrella structures. The benefit of the new structure compared to the existing umbrella structures is a much easier working principle, which allows leaving the complex moving elements and joints. The main advantage of this structure comes from its simplicity as it simplifies the operation of umbrellas, making it a cost-effective and sustainable option.

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Author: Norbert Vasváry-Nádor
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In the recent years the Author participated in two Intelligent Energy Europe projects, which aim was to deliver transport-sector energy savings by creating travel plans. During the development of the projects two local travel plans were worked out, one for the residential area of Győr-Ménfőcsanak, Hungary and one for the elementary educational institutions of Győr. In 2012 additional travel plans were developed, this time for other target groups, one for the universities of Győr, and another one for the employees of three public institutions. The main objective of these studies was to reduce the problems, caused by private car users and more over to promote sustainable mobility choices for target groups. The results of the projects showed, that travel plans are effective tools in order to solve mobility challenges in a sustainable way, but transportation infrastructure and services have strong effect on the success of travel plans.

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Initiation of traffic calming measures is on the challenging agenda of most cities, which are in pursuit of creating livable urban areas. However, previous studies on this research pointed out that the knowledge of the strategic aspects of application of these restrictions is insufficient, which is blocking further progression. Therefore a comprehensive policy assessment framework has been proposed and developed, which is combining modern modeling tools with reliable, well-tried appraisal methods. This work is another milestone of this broader research and its aim is to elaborate the modeling part of the framework enabling and establishing further works. The objective of this paper is to give an overview on this process and the result of which is a land-use and transport interaction model. In addition, it is also intended to practically test the model on a hypothetical case and to demonstrate its suitability.

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The paper presents results of exceptional experimentation, which focuses on the long-term loading of timber beams. The uniqueness of the research is given by real dimensions of samples and by the term of loading over one year. In the frame of investigation four currently often used timber girders had been investigated. The aim was to observe the time dependence of deflections over time. According to deflection curves the approximations for simulating the final deflection at the end of structure’s lifetime had been defined. The obtained creep coefficients were compared with the values listed in the valid standards.

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Authors: Klára Machalická, Martina Eliášová and Michal Netušil

Thanks to intensive research in the field of polymer adhesives in the last few years, there is a possibility of using a glued joint with a real load bearing role. The reliability of adhesive in the connection during the lifetime of a structure is affected by many factors, but the initial choice of a proper adhesive material is the most crucial one. The article deals with the experimental analysis focused on the determination of material characteristics of adhesives in planar connections, it describes the effect of various factors on the behavior of an adhesive joint under increasing loads, its ultimate bearing capacity and its failure modes. The main investigated factors are the type of adhesive, the type of connected materials (material of substrate), surface treatment and the thickness of the adhesive layer. A special part of the article describes numerical models of a glued joint with respect to different types of adhesive.

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Authors: Ildiko Jancskar, Zoltan Sári, Adam Schiffer and Geza Várady

The paper suggests a design procedure for fuzzy cascade control. The expert knowledge based tuning procedure is supported by investigation the phase plane of the reference tracking. The plant is a one degree of freedom helicopter model with highly non-linear dynamics in a hardware-in-the-loop arrangement. Starting from a common fuzzy-PI controller in the outer loop and classic PI-controller in the inner loop, the presented tuning procedure enables to obtain fuzzy-adaptive parameter settings of the inner-loop and a heuristic modified rule base in the outer loop. The developed control strategy proves to be very successful: both the settling times and overshoots have become well regulated.

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Mining and processing activities in the former mining Middle Spis area caused serious environmental problems. The aim of the study is to determine the content of heavy metals (Cu, As, Pb, Fe, Hg) in water and describe the flora diversity along the Rudnansky creek, which flows through the area. Chemical (pH) and physical (water conductivity, oxygen saturation) water properties were also evaluated. High values of copper and mercury were determined at the localities close to the tailing pond and mercury processing plant. Presence of plant species resistant to heavy metals, such as Calamagrostis epigejos, Arctium lappa, Cirsium rivulare, Geranium palustre, indicates toxic element pollution.

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The mining industry located in the Mecsek Hills has played a decisive role in the life of Pécs, which developed into an industrial settlement in the 19th century. Although the extraction of raw materials was discontinued in the last Pécs mine in 2004, the mining industry as a mental and built heritage still remains. Smaller estates, characteristic colonies of the early years of mining, have been significantly re-evaluated. The parts of the city built near the previous workplaces, far from the center, serve as the residence of people with the lowest income. The majority of approximately 4 000 municipal rental-housing units belong to this type of environment. Therefore, the future of the former mining colonies is crucial for the local government.

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Municipal solid waste management is a basic service that, in Finland, consists of collection, transportation and treatment systems provided by municipalities, waste management companies and producer responsibility organizations. The amount of municipal solid waste in Finland has risen quite steadily for many decades. In 2012, the recovery rate of municipal solid waste as material or energy was 67%. The Finnish Waste Act has been updated in 2012, with the key goal to further reduce waste amounts and progress recycling. The paper describes the best practices in strategic waste management planning and describes the organization of municipal solid waste in city of Oulu, Finland.

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Authors: Eva Pongrácz, Johanna Niemistö, Verónica García, Niko Hänninen, Paula Saavalainen and Riitta Keiski

Further to Directive 2009/28/EC on the promotion of the use of energy from renewable sources, the share of biofuels in transport should rise to a minimum of 10% in Member States by 2020. In Finland, the goal is set at 20%, and it is estimated that this can be produced entirely in domestic factories, as long as the projects already underway will be successful and additional industrial-scale biofuel plants would be built. The paper reviews the state of projects underway in Finland, and outlines current research activity in promoting waste and by-product — based biofuels.

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The effect of emergent aquatic canopy on over-lake wind field was investigated through detailed field measurements. The aerodynamic roughness length above reed canopy and above open water was determined from eddy-covariance data. It was found that the aerodynamic roughness length at short fetches could be more sufficiently estimated from wave age relations than from the logarithmical profile formula, indicating that near the canopy wind profile might deviate from the theoretical logarithmical form. The presented calculations lead to an improved understanding of the wind profile realignment and wind shear stress development at the interface of the characteristic lake zones, also enhancing the accuracy of the modeling of various wind-induced processes.

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The world’s energy consumption continues to increase, which results in demographic changes, living standard increases and technical development. In the world and Hungary the interest in biomass crops also has increased considerably over the previous decades. This paper summarizes the most important biological, biotechnological and agronomical researches and results of our working group, in Department of Agricultural Botany, Plant Physiology and Plant Biotechnology, University of Debrecen. It represents our research group publications and introduces some efficient propagation possibilities of promising new perennial bioenergy crops, giant reed (Arundo donax L.) and Virginia fanpetals (Sida hermaphrodita Rushby).

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Based on the general mathematical model of Dudás [3, 4] — which is appropriate for mathematical modelling of production technology methods and various toothed gear pairs — we have generated mathematical models which are appropriate for determination of tooth surface points of face gear and worm gear connection with conical and cylindrical worm by numerical way. After doing the necessary calculations, the CAD models of the worm gear drives could be generated. Based on these there is an opportunity for rapid prototyping (RP) technology for other connection and production geometric analysis.

For the verification of our calculated results, we generate CAD models of one to one given geometric conical and cylindrical worm gear drives for other analysis.

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The aim of this research was to assess the total antioxidant activity (TAA) of lipophilic (Lextr) and hydrophilic (Hextr) tomato extracts using in vitro chemical tests and cell-based assays, focusing on possible synergistic actions between tomato antioxidants. Both Hextr and Lextr were HPLC analysed for their carotenoids, phenolic compounds, and ascorbic acid contents. For the evaluation of TAA, extracts were assayed alone or in combination using in vitro chemical tests (TEAC, FRAP) and cell-based (CAA) assays using human hepatoma (HepG2) and human histiocytic lymphoma (U937) cells. The only carotenoid detected in Lextr was lycopene, while a mixture of phenolic compounds (chlorogenic acid, caffeic acid, and rutin) was identified in Hextr. Ascorbic acid was not found either in Hextr or in Lextr. Upon extract combination (1:1, v/v), the FRAP assay revealed additive action between Lextr and Hextr, whilst a slight synergistic action was observed in TAA as measured by the TEAC assay. Synergistic action was better revealed when TAA was analysed using either U937 or HepG2 cells. This could be explained by the presence of a multiphase media (cell membrane and extra- and intracellular media) that might facilitate the distribution and interaction of antioxidants with different polarities and different mechanisms of action.

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Caffeine is a bitter, white crystalline xanthine alkaloid that is synthesized in different parts of more than 60 plant species. In a previous study, caffeine content of 377 food samples obtained from the Hungarian market was measured by a validated HPLC technique. These analytical data were built up into a food composition database called NutriComp. Dietary caffeine intake of the Hungarian population was estimated based on the data of the National Nutritional Status Survey 2009. Daily caffeine intake of Hungarian adult males and females were 147±6.2 mg per capita (95% CI: 135–160), and 138±4.2 mg per capita (95% CI: 129–147), respectively. There was no significant difference between genders. The oldest men and women consumed significantly less caffeine than the people between 35–64 years of age. The main sources of caffeine are coffee and tea with 58–59%, and 35–37% of the total intake in men and women, respectively.

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The main goal of this study was to investigate the effects of moderate saline water irrigation on the composition and quality of olive oil of the “Chemlali” olive cultivar in comparison to a control plot grown under rain-fed conditions from two methods of olive tree propagation (suckers and cuttings). The antioxidant compounds, oxidative stability and volatile compounds of virgin olive oil samples were determined and reported. The irrigation did not affect free acidity and peroxide value and specific ultraviolet absorbance (K232, K270). Whereas, fatty acid composition, oxidative stability, total phenol, total chlorophyll and carotenoid contents were affected by irrigation. Rain-fed virgin olive oils showed a statistically significant higher content of oleic and linoleic acids. However, olive oil samples obtained from fruit of irrigated trees from suckers had a higher content of (E)-2 hexenal (67.2%) and a higher content of total phenols (860 mg kg–1). Interestingly, more stable oil was obtained from moderate saline water irrigated trees from suckers compared to olives from cuttings.

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Authors: K. Pogoń, M. Sady, G. Jaworska and T. Grega

The aim of the present work was to determine the populations of ABT culture microorganisms in orange and orangewhey drinks after fermentation and during 28-day storage. The evaluation involved fermented fruit drinks without whey or with added acid or sweet (rennet) whey. The Streptococcus thermophilus and Bifidobacteria counts were initially 3.5×105–8.3×105 CFU cm−3 and 2.4×106–5.9×106 CFU cm−3, respectively, and did not increase during fermentation. However, an increase was observed in the Lb. acidophilus count, which amounted to 3.0×106–2.4×107 CFU cm−3 after fermentation. During storage, the Str. thermophilus and Lb. acidophilus counts remained constant, but that for Bifidobacteria fell to 103 CFU cm−3 after 28 days. Bacteria survivability was higher in drinks containing whey than in non-whey orange drinks. In 100 cm3, antioxidant activity against ABTS/DPPH radicals varied between 260 and 550 μmol TE; vitamin C content was in the range of 15.7–17.6 mg; polyphenols were 26.6–34.4 mg (+)catechin. In the sensory evaluation the best results were obtained for non-whey drinks and those containing 50% acid whey.

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The chemical and microbiological changes during spontaneous <italic>budu</italic> fermentation were elucidated on monthly basis (1–12 months). A significant increase (P<0.05) in pH, acidity, soluble protein, total protein, and moisture content was observed during <italic>budu</italic> fermentation, except for the fat content. The total microbial load decreased gradually from the initial of 6.13±0.01 to 3.45±0.13 log CFU g−1 after 12 months of fermentation. Overall, 150 isolates were identified, with a majority of bacteria (77%), followed by yeasts (12%) and 11% of unconfirmed species. Micrococcus luteus was the predominant strain that initiated the fermentation before it was replaced by Staphylococcus arlettae that exists throughout the fermentation. This study confirmed that lactic acid bacteria and yeasts often coexist with other microorganisms, even though a microbiological succession usually takes place both between and within species, which shaped the chemical and sensory characteristics of the final product. In addition, some of the isolates could be potentially valuable as starter cultures for further improved and controllable <italic>budu</italic> fermentation.

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With the knowledge of the advantageous characteristics of the cylindrical worm gear drives having arched profile in axial section and the conical worm gear drives having linear profile in axial section, a new geometric type conical worm gear drive has been designed and then manufactured, that is the conical worm gear drive having arched profile in axial section. Under same load and boundary conditions in case of the same geometric spiroid worm gear drives having arched profile and having linear profile in axial section we have done comparative finite element method analysis for evaluating the strains, deformations and stresses of this gear drives.

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A rapid and reliable liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) method was developed for the determination of acrylamide in three different local bread types; wheat bread, bran bread, whole wheat bread. Acrylamide analyses were made in crust parts of the 85 bread samples. The method was linear up to 750 μg kg–1 food with a determination coeffi cient of 0.999. Recovery rate was found 99.3% with limit of detection and limit of quantifi cation values of 1.5 μg kg–1 and 5.0 μg kg–1, respectively. Certifi ed reference materials of crisp bread were analysed and acrylamide contents of these samples were found in the range cited in the certifi cates. Statistical correlations were investigated between acrylamide contents and protein contents, reducing sugar contents, moisture contents, pH, and colour parameters (L*, a*, b*) of bread samples. Sample preparation procedure and chromatographic conditions of acrylamide analysis were investigated in more detail, and a rapid, accurate, precise, and reliable analysis method was developed.

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Sunflower (PSH 569) was used to obtain textured defatted meal. Proximate analysis, water absorption index (WAI), water solubility index (WSI), fat absorption capacities (FAC), foaming capacity (FC), and bulk density (BD) were determined. The objective of the study was the optimization of extrusion conditions for production of textured defatted sunflower meal using response surface methodology (RSM) by evaluating functional properties. It was dried, grinded, and sieved to eliminate hull and fibre. Numerical optimization provided eight solutions with desirability value varying from 0.81 to 0.82. Range of predicted values of FAC (80.96–90.49), WHC (1.95–2.12), WSI (3.22–3.36), WAI (2.84–3.08), bulk density (0.31–0.36), and foaming capacity (14.39–16.30) were used for numerical optimization. Best extrusion conditions were 16.36% feed moisture, 300 r.p.m. screw speed, and 149.40 °C barrel temperature. Textured sunflower defatted meal was prepared using the above optimized conditions.

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This study measured the flow behaviour of whey protein isolate mixtures with cinnamic or ferulic acids. Samples were heated in a vacuum (80 °C, –0.9 atm, 280 r.p.m., 0.5 h). The flow curves of all samples showed a non- Newtonian shear thinning flow and the viscoelastic properties were typical for weak gel systems. At pH 6.0, 6.7, and 8.0, the highest shear stress values were obtained with 20, 40, and 40 mg of cinnamic acid g–1 protein, respectively. At pH 6.0, the use of ferulic acid (20 mg g–1 protein) resulted in the elevation of shear stress values, but at pH 8.0, ferulic acid caused a decrease in shear stress values in comparison to cinnamic acid. The thixotropic area (AT) was increased in mixtures containing 20–40 mg cinnamic acid g–1 protein (at pH 6.7) and 20 mg of cinnamic acid g–1 protein (at pH 6.0). Similarly, the addition of ferulic acid (40 and 20 mg g–1 protein at pH 6.7 and 6.0, respectively) caused a significant increase in AT. At pH 8.0, no significant differences in AT values were observed between samples. Such systems can be applied with reference to health promoting foods such as WPI-based desserts.

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The aim of this study was to evaluate suitability of legumes as carriers for probiotic strain Lactobacillus rhamnosus GG, leading to the development of new probiotic foods for consumers who have to restrict or dislike dairy products. The growth and metabolic activity of the probiotic strain Lactobacillus rhamnosus GG during fermentation of waterbased leguminous porridges, prepared from soy bean, soy flour, green lentil, husked lentil, white bean, speckled bean, red bean, yellow pea, chickpea, and chickpea flour, were monitored. Viable cell counts, pH values, and contents of organic acids were analysed during static fermentation of autoclaved substrates at 37 °C for 48 h. Lactobacillus rhamnosus GG was able to grow up to the counts higher than 6 log CFU g–1 (measured values in the range of 7.8–8.9 log CFU g–1), which is legislative limit for labelling food as probiotic. pH values of fermented substrates varied between 4.0–6.0, concentration of lactic acid ranged from 99.9 to 687.7 mg kg–1, and level of acetic acid varied from 266.1 to 1182.0 mg kg–1.

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Authors: M. Dimitrovska, M. Bocevska, D. Dimitrovski and D. Doneva-Sapceska

The evolution of individual anthocyanins during vinification of Merlot and Pinot Noir grapes was studied using two different winemaking procedures for each grape variety. Additionally, the effect of the applied vinification on the anthocyanin composition of the obtained wine at the end of maceration and wine aged 6 months was investigated and compared with the anthocyanin patterns of the original grape. The dynamics of the extraction process was monitored daily during maceration by analysing the anthocyanins in the must using HPLC. The results showed that the anthocyanin composition of young wines was different from that of the grapes. The proportions of malvidin-3- glucoside and malvidin-acetate were higher in wines than in the grape skins, but this was not the case for malvidin coumarate. Application of different vinification procedures to the same raw material resulted in wines with similar anthocyanin patterns. However, the anthocyanin profiles changed with the ageing of the wines.

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The milk thistle plant grows in many regions in Tunisia; however, there is no literature regarding their oil composition. In this study, oil content, fatty acids and triacylglycerols compositions of milk thistle seeds growing wild in Tunisia were determined. The oil content was 30.5%, thus milk thistle seeds could be exploited as natural new source of oil. Among the fatty acids, linoleic acid had the highest percentage (59.98%) followed by oleic acid (21.26%) and palmitic acid (12.74%). The extracted oil from milk thistle seeds is rich in polyunsaturated fatty acids (60.37%). Various molecular species of TAGs were detected and the major forms were LLL (22.30%), OLL (20.40%), PLL (17.31%), POL (14.30%), and OOL (7.90%). It can be concluded that milk thistle seed oil has a characteristic TAG pattern as compared with these elucidated for olive oil and soybean oil.

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According to the Energy Performance of Buildings Directive, a significant share of the energy consumption of nearly zero energy buildings is covered from renewable energy. Biomass is considered as one of the most important renewable sources. It is promising since most of the Member states apply very low primary energy conversion factors for it. Nevertheless, the primary energy need is not as favourable as the conversion factors suggest, due to the efficiency of the biomass boilers for all over the year which depends on the changing load. Heating systems supplied with biomass boilers need buffer storage tanks which further decrease the efficiency of the system.

The nearly zero energy buildings, especially those of residential use exhibit more stable load due to the lower heat loss and the overwhelming share of the net energy need of domestic hot water supply.

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The effect of a pure endoxylanase (Xyn2) and endoglucanase (EgII) from Trichoderma reesei on bread flour quality were compared to a commercial endoxylanase from Aspergillus niger (Com-xyl) and a cellulase-xylanase cocktail from T. reesei (Cel-xyl). Effects of these enzymes on dough quality, bread weight, height and crumb softness were analysed. Results obtained during commercial-scale baking tests often differed from those obtained during laboratory-scale tests; indicating that results from laboratory-scale baking tests cannot be extrapolated to commercialscale bread production. Low levels of endoxylanase activity benefited bread height and volume without affecting slice brightness in commercial-scale tests. The addition of endoglucanases and α-amylases can also be advantageous resulting in less endoxylanase activity required to obtain similar results.

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Authors: D. Varga, Zs. Sándor, Cs. Hancz, I. Csengeri, Zs. Jeney and Zs. Papp

The aim of our study was to survey the geosmin (GSM) and 2-methylisoborneol (MIB) concentrations of the sediment and that of common carp (Cyprinus carpio) flesh in three different Hungarian fish farms (clayey, marshy, and sodic ponds).

Results showed that the concentrations of off-flavour compounds of the sediment and fish fillets were related to the natural environment. The GSM concentration of bottom soil samples was higher, than MIB in each fish farm. Both off-flavour compounds were the highest in the marshy fish pond and the lowest in the sodic pond. In case of fish flesh, significant differences were found between the farms in GSM level and fat content. In the fish flesh the same tendency was found as in the sediments, but surprisingly, MIB concentration was higher in the fillets, referring to accumulation.

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Authors: G. Szabó, P. Enyedi, Gy. Szabó, I. Fazekas, T. Buday, A. Kerényi, M. Paládi, N. Mecser and Sz. Szabó

According to the challenge of the reduction of greenhouse gases, the structure of energy production should be revised and the increase of the ratio of alternative energy sources can be a possible solution. Redistribution of the energy production to the private houses is an alternative of large power stations at least in a partial manner. Especially, the utilization of solar energy represents a real possibility to exploit the natural resources in a sustainable way. In this study we attempted to survey the roofs of the buildings with an automatic method as the potential surfaces of placing solar panels. A LiDAR survey was carried out with 12 points/m2 density as the most up-to-date method of surveys and automatic data collection techniques. Our primary goal was to extract the buildings with special regard to the roofs in a 1 km2 study area, in Debrecen. The 3D point cloud generated by the LiDAR was processed with MicroStation TerraScan software, using semi-automatic algorithms. Slopes, aspects and annual solar radiation income of roof planes were determined in ArcGIS10 environment from the digital surface model. Results showed that, generally, the outcome can be regarded as a roof cadaster of the buildings with correct geometry. Calculated solar radiation values revealed those roof planes where the investment for photovoltaic solar panels can be feasible.

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Potato wedges were deep, shallow, and par-fried in soybean, sesame, and mustard oils using a laboratory formulated citric acid based antioxidant. The wedges were stored at –18 °C for 10, 20, 30, and 40 days. The quality of the wedges was assessed by subjective method (sensory analysis) and objective method (texture studies). Fuzzy logic was applied as a tool to analyze the linguistic data of subjective evaluation. Objective evaluation was conducted by studies on hardness, shear modulus and shear energy of the wedges. The wedges with highest defuzzified scores (obtained by sensory evaluation) and minimum changes in textural properties (P<0.05) were obtained in par-fried soybean oil (after 40 days storage) and in deep fried sesame and mustard oils (both after 30 days storage). The ranking of fried wedges (in the antioxidant administered oils) based on defuzzified scores after 40 days were: sesame > mustard > soybean (deep fry), mustard > soybean > sesame (shallow fry) and soybean > mustard > sesame (par-fry).

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The aim of this study was to evaluate the physical, chemical, and functional properties of recovered proteins of anchovy (Engraulis anchoita) and whitemouth croaker (Micropogonias furnieri) through the process of alkaline solubilisation and isoelectric precipitation, using different solubilisation (NaOH and KOH) and precipitation (HCl and H3PO4) reagents. The tests showed high protein level, and the lowest lipid reduction (94.5%) was found in the recovered protein of anchovy, the lowest yield of the process was 76.1%. The highest whiteness (78.8 and 74.2) was found in whitemouth croaker proteins. The solubilisation of the recovered protein was studied in the pH range (3, 5, 7, 9, and 11). The maximum solubility was at pHs 3 and 11 and minimum solubility was at pH 5 in the species under study.

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This article has been withdrawn - upon request by authors - by Akadémiai Kiadó due to suspected plagiarism.

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Wheat, an important staple cereal crop cultivated in seleniferous region of India, noted to accumulated significantly high concentrations of Se, was examined for the distribution of selenium in various protein fractions of the grains. Amongst the protein fractions, Se was dominantly (33–37%) present in the albumin fraction in Se rich grains followed by other fractions viz., globulin (20–25%), glutelin (20–25%), and prolamin (17–20%). The observations are important in context of exploring the use of this material as functional foods in formulating Se-enriched diets for Se-deficient population.

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This study discusses the economic utilization of proton exchange membrane fuel cell (PEMFC) based on cost of energy (COE) to supply residential electrical and thermal loads. The fuel cell system is sized using simplified mathematical expressions considering the stack degradation and the system salvage value at the end of its life time. The study is based on a 5 kWh/day residential load with a peak load power of 1300 W. Two scenarios for economic survey are studied. The first scenario is to find the commercial price for each FC component considering that the supply fuel is hydrogen. The other scenario is for a complete FC system commercial price considering that the supply fuel is natural gas. The economic analyses are based on the actual sale prices in the market. The COE of the fuel cell system is compared with previous work by the authors for the same residential ratings but supplied from a stand-alone photo voltaic system (SAPV). The analysis results show that the COE relies heavily on the capital cost of the system.

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Authors: R.V Salamon, É. Vargáné-Visi, Cs.D. András, Zs. Csapóné Kiss and J. Csapó

The addition of synthetic CLA is a possible way in order to compose foods enriched with conjugated linoleic acids (CLAs). The most environmental friendly methods for CLA synthesis are based on microbial biosynthesis. With homogeneous catalysis using organometallic catalysts (Ru and Rh complexes) high (approximately 80%) yields were obtained with high selectivity related to bioactive isomers. The heterogeneous catalysis has the advantage that at the end of the reaction there is no need for a supplementary separation operation or recycling of the catalyst. In heterogeneous process, the maximum yield may even be higher than 90% and the selectivity remains quite high as the reaction conditions are optimized. The substrates for obtaining CLAs are, in general, linoleic acid or alkyl linoleates and the catalysis is acidic. The yield and the selectivity depend on the strength and the type of acidic sites, as well as on the size distribution of the particles. Beside the existing catalytic methods, a photocatalytic process with UV and visible light irradiation with iodine promoter can be applied.

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The aim of this paper is to provide an overview of the tendencies of development in the construction industry, one of the most important foundations of economic development, between 2000 and 2012. The key findings of the study may be summarized in the following:

– In the period between the 2000 and 2012, after the increasing tendency that could be observed in the first half of the first decade in the new millennium, a significant drop occurred both in terms of the value of production and the number of employees in the construction industry.

– From the three subsectors of the construction industry, it was the construction of buildings on which the economic crisis that started in 2008 had a negative impact.

– The territorial tendencies of the construction industry were influenced by large-scale infrastructural investments (motorway construction, railway network development).

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The management of an urban context in a Smart City perspective requires the development of innovative projects, with new applications in multidisciplinary research areas. They can be related to many aspects of city life and urban management: fuel consumption monitoring, energy efficiency issues, environment, social organization, traffic, urban transformations, etc.

Geomatics, the modern discipline of gathering, storing, processing, and delivering digital spatially referenced information, can play a fundamental role in many of these areas, providing new efficient and productive methods for a precise mapping of different phenomena by traditional cartographic representation or by new methods of data visualization and manipulation (e.g. three-dimensional modelling, data fusion, etc.). The technologies involved are based on airborne or satellite remote sensing (in visible, near infrared, thermal bands), laser scanning, digital photogrammetry, satellite positioning and, first of all, appropriate sensor integration (online or offline).

The aim of this work is to present and analyse some new opportunities offered by Geomatics technologies for a Smart City management, with a specific interest towards the energy sector related to buildings. Reducing consumption and CO2 emissions is a primary objective to be pursued for a sustainable development and, in this direction, an accurate knowledge of energy consumptions and waste for heating of single houses, blocks or districts is needed.

A synoptic information regarding a city or a portion of a city can be acquired through sensors on board of airplanes or satellite platforms, operating in the thermal band. A problem to be investigated at the scale

A problem to be investigated at the scale of the whole urban context is the Urban Heat Island (UHI), a phenomenon known and studied in the last decades. UHI is related not only to sensible heat released by anthropic activities, but also to land use variations and evapotranspiration reduction. The availability of thermal satellite sensors is fundamental to carry out multi-temporal studies in order to evaluate the dynamic behaviour of the UHI for a city.

Working with a greater detail, districts or single buildings can be analysed by specifically designed airborne surveys. The activity has been recently carried out in the EnergyCity project, developed in the framework of the Central Europe programme established by UE. As demonstrated by the project, such data can be successfully integrated in a GIS storing all relevant data about buildings and energy supply, in order to create a powerful geospatial database for a Decision Support System assisting to reduce energy losses and CO2 emissions.

Today, aerial thermal mapping could be furthermore integrated by terrestrial 3D surveys realized with Mobile Mapping Systems through multisensor platforms comprising thermal camera/s, laser scanning, GPS, inertial systems, etc. In this way the product can be a true 3D thermal model with good geometric properties, enlarging the possibilities in respect to conventional qualitative 2D images with simple colour palettes.

Finally, some applications in the energy sector could benefit from the availability of a true 3D City Model, where the buildings are carefully described through three-dimensional elements. The processing of airborne LiDAR datasets for automated and semi-automated extraction of 3D buildings can provide such new generation of 3D city models.

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