Our study aimed to understand the origin of elevated (>100 mBqL–1) gross alpha activity measured in groundwater-derived drinking water in the vicinity of the Sopron Mountains and Lake Fertő (Neusiedl). Water samples from 10 springs and 7 water wells were analyzed for major ions and trace elements. Total U and 226Ra activity concentrations were determined by alpha spectrometry using Nucfilm discs, and 222Rn activity was measured by liquid scintillation counting. 234U/238U ratio was determined by ICP-MS and alpha spectrometry. Additionally, δ2H and δ18O measurements were performed. To get an insight into the dynamics of the groundwater flow system and to better understand the radionuclide mobilization and transport processes, the geochemical results were evaluated in the groundwater flow system context.Uranium activity was measured up to 540 mBqL–1, thus it can be concluded that dissolved uranium causes the previously measured elevated gross alpha values, though no health risk arises from drinking water consumption. The occurrence of dissolved uranium can be explained by oxidizing conditions that are prevalent along local flow systems and in recharge areas. The relatively short residence time of water, thus the presence of local flow systems is indicated by δ18O (-11.96 to -7.17‰) and δ2H values (-83.4 to -52.6‰). Spring samples have lower uranium activity (up to 93 mBqL–1) than groundwater samples (up to 540 mBqL–1) which can be explained by the longer residence time of water. Uranium is transported along flow paths under oxidizing conditions and the longer the flow route the higher the uranium concentration.This topic is part of a project that has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No. 810980. Besides, the research was funded by the National Multidisciplinary Laboratory for Climate Change, RRF-2.3.1-21-2022-00014 project project. Some radioactivity measurements were supported by the European Commission’s Joint Research Centre (JRC) – Research Infrastructure Access Agreement No. 36227-1/2021-1-RD-EUFRAT-RADMET.

Groundwater quality constantly evolves through rock–water interactions, which can enrich groundwater with undesirable elements such as naturally occurring radionuclides. The aim of this study was to understand the cause of gross alpha activity exceeding the screening value of 0.1 Bq L−1 measured in groundwater-derived drinking water in the vicinity of a metamorphic outcrop in Hungary. As groundwater quality is strongly dependent on the properties of groundwater flow systems, environmental tracers (δ2H and δ18O composition, 226Ra, 222Rn, total U activity concentration, and 234U/238U ratio) and hydraulic evaluation were applied to understand groundwater dynamics. The collected groundwater samples had total U activities up to 540 mBq L−1, which translates into an indicative dose below the drinking water parametric value. However, in the presence of dissolved uranium, the δ2H (−52.6–(−83.4)) and δ18O (−7.17–(−11.96)) values led to the conclusion that local flow systems were sampled that are known to be most vulnerable to any changes in their recharge area. The results confirm that the groundwater flow system approach involving environmental tracers and hydraulic evaluation is a powerful tool for identifying the cause of natural radioactivity in groundwater-derived drinking water.

A kétrészes tanulmánysorozat a Wikidata felépítését, szemantikus weben betöltött szerepét és lehetséges alkalmazási módozatait vizsgálja nemzetközi példák bemutatása és szakirodalmi áttekintése által. A szándék kettős: magyar nyelven íródott szakirodalom hiányában átfogó és teljes áttekintést nyújtani a Wikidatáról, összefoglalva a tudásgráffal kapcsolatos legfontosabb kutatási eredményeket, másrészről bemutatni a Wikidata integrálásának megvalósult jógyakorlatait és lehetséges alkalmazásait, különös tekintettel a közgyűjteményi szereplők szempontjából. Az 1. részben feltárásra kerülnek mindazon kezdeti fejlesztési célok és lépések, amelyek az adatbázis ma ismert formájához vezettek. Az adatok RDF tripletként történő tárolásához szükséges szemantikus struktúra meghatározását követően bemutatásra kerül a Wikidata közösségi közreműködésen alapuló modellje és a többnyelvű adatok kezelésének mikéntje.

Water vapor flux plays a crucial role in surface-atmosphere exchange processes as evapotranspiration regulates the energy balance of the surface. Moreover, it transfers water vapor into the atmosphere and, as a result, shapes the hydrological cycle. The eddy-covariance (EC) technique is the most commonly applied method to directly measure water vapor flux over a wide variety of surfaces. An EC arrangement consists of a 3D sonic anemometer and a gas analyzer. To derive surface fluxes, wind components and the gas concentration (e.g. water vapor) have to be recorded with high-frequency (at least at 10 Hz). In the case of open-path (sampling-free) EC systems, infrared (IR) gas analyzers are used dominantly, which are still quite large so that e.g. they cannot be easily mounted on drones. In contrast, small and light sonic anemometers are available for flux measurements.In this study, we present the application of a sampling-free photoacoustic (PA) sensor for water vapor flux measurement employing the EC technique. The fast response PA sensor records the water vapor concentration through an open cylindrical chamber having an overall size of less than 1 dm3. On the one hand, a previous first test showed that the vertical covariance functions obtained by the PA cell follow closely to those resulting from an accepted IR sensor. On the other hand, the PA system showed some underestimation at higher frequencies based on the analysis of co-spectra. To comprehensively test and evaluate the PA cell for flux measurements, a seven-week-long field measurement was performed over a plain grassland when a calibrated EC150 IR sensor (Campbell Sci.) was used as a reference gas analyzer. We analyze the accuracy of the PA system: (i) depending on the orientation of the cell or i.e. the wind direction, and (ii) for a broad range of meteorological conditions, such as different wind speeds and atmospheric stability. Furthermore, to overcome the high-frequency attenuation, we establish and apply empirical spectral transfer functions following the literature and standard EC postprocessing procedures. The characteristic response time of the PA sensor is also assessed.

As groundwater is an important source of drinking water, its quality is of great importance. In recent years, following the EU regulations, radioactivity parameters are also included among the quality measures. In the area of the city Sopron (Hungary), groundwater resources are used for drinking water supply. The area had been actively researched for fissile materials, and previous studies measured high radon activity for example in the geophysical observatory (500–1000 kBq m–3) and in natural springs (up to 220 Bq L–1). Natural springs bear important information about their parent flow systems, about the transit time and the rock-water interactions along the flow paths. The aim of the study was to investigate the natural springs of the Sopron Mountains and to measure not only the physico-chemical properties (discharge rate, pH, electrical conductivity, temperature, dissolved oxygen content, redox potential, major ion content), but also to determine the uranium, radium and radon activity concentration of the springwaters. The measurements revealed low discharge rate (< 5 L min–1), low dissolved solid content (< 450 mg L–1 TDS) and temperature (10–12°C) for the majority of the springs, which indicate that the waters travel in the subsurface along local flow systems. Two springs, which are situated in the foothills, i.e. at lower elevation, show higher dissolved solid content (1115 mg L–1, 481 mg L–1) and higher temperature (15.6°C, 16°C). Their uranium content was also higher, 86–93 mBq L–1. In the case of these springs, the physico-chemical parameters suggest longer travel time, i.e. more time for rock-water interactions which is reflected in their higher dissolved solid and uranium content. Radon exceeding the 100 Bq L–1 activity concentration was measured in two springs. For the other springs, the radon concentrations were 2-79 Bq L-1. As all the springs are situated in the regional recharge area of groundwater resources of the area, the study delivered important information regarding the rock-water interactions and the improvement of groundwater quality during subsurface reactions.

The enzyme family harboring the post-translationally formed 5-methylene-3,5-dihydro-4H-imidazol-4-one (MIO) catalytic residue comprises both aromatic amino acid ammonia-lyases (ALs) and 2,3-aminomu...

Circadian leaf movements are widely known in plants, but nocturnal movement of tree branches were only recently discovered by using terrestrial laser scanning (TLS), a high resolution three-dimensional surveying technique. TLS uses a pulsed laser emitted in a regular scan pattern for rapid measurement of distances to the targets, thus producing three dimensional point cloud models of sub-centimeter resolution and accuracy in a few minutes. Here, we aim to gain an overview of the variability of circadian movement of small trees across different taxonomic groups, growth forms and leaf anatomies. We surveyed a series of 18 full scans over a 12-h night period to measure nocturnal changes in shape simultaneously for an experimental setup of 22 plants representing different species. Resulting point clouds were evaluated by comparing changes in height percentiles of laser scanning points belonging to the canopy. Changes in crown shape were observed for all studied trees, but clearly distinguishable sleep movements are apparently rare. Ambient light conditions were continuously dark between sunset (7:30 p.m.) and sunrise (6:00 a.m.), but most changes in movement direction occurred during this period, thus most of the recorded changes in crown shape were probably not controlled by ambient light. The highest movement amplitudes, for periodic circadian movement around 2 cm were observed for Aesculus and Acer, compared to non-periodic continuous change in shape of 5 cm for Gleditschia and 2 cm for Fargesia. In several species we detected 2–4 h cycles of minor crown movement of 0.5–1 cm, which is close to the limit of our measurement accuracy. We present a conceptual framework for interpreting observed changes as a combination of circadian rhythm with a period close to 12 h, short-term oscillation repeated every 2–4 h, aperiodic continuous movement in one direction and measurement noise which we assume to be random. Observed movement patterns are interpreted within this framework, and connections with morphology and taxonomy are proposed. We confirm the existence of overnight “sleep” movement for some trees, but conclude that circadian movement is a variable phenomenon in plants, probably controlled by a complex combination of anatomical, physiological, and morphological factors.

Surface reconstruction from point clouds generated by laser scanning technology has become a fundamental task in many fields of geosciences, such as robotics, computer vision, digital photogrammetry, computational geometry, digital building modelling, forest planning and operational activities. Point clouds produced by laser scanning, however, are limited due to the occurrence of occlusions, multiple reflectance and noise, and off-surface points (outliers), thus necessitating the need for robust fitting techniques. In this contribution, a fast, non-iterative and data invariant algebraic algorithm with constant O(1) complexity that fits planes to point clouds in the total least squares sense using Gaussian-type error distribution is proposed. The maximum likelihood estimator method is used, resulting in a multivariate polynomial system that is solved in an algebraic way. It is shown that for plane fitting when datasets are affected heavily by outliers, the proposed algebraic method can be embedded into the framework of robust methods like the Danish or the RANdom SAmple Consensus methods and computed in parallel to provide rigorous algebraic fitting with significantly reduced running times. Compared to the embedded traditional singular value decomposition and principal component analysis approaches, the performance of the proposed algebraic algorithm demonstrated its efficiency on both synthetic data and real laser-scanned measurements. The evaluation of a symbolic algebraic formula is practically independent of the values of its coefficients; however, the computation of the coefficients depends on the complexity of the data. Since the main advantage of the symbolic solution is its non-requirement of numerical iteration, the data complexity will have weak influence on the speed-up. The novelty of the proposed method is the use of algebraic technique in a robust plane fitting algorithm that could be applied to remote sensing data analysis/delineation/classification. In general, the method could be applied to most plane fitting problems in the geoscience field.

Web-based photo albums that support organizing and viewing the users’ images are widely used. These services provide a convenient solution for storing, editing and sharing images. In many cases, the users attach geotags to the images in order to enable using them e.g. in location based applications on social networks. Our paper discusses a procedure that collects open access images from a site frequently visited by tourists. Geotagged pictures showing the image of a sight or tourist attraction are selected and processed in photogrammetric processing software that produces the 3D model of the captured object. For the particular investigation we selected three attractions in Budapest. To assess the geometrical accuracy, we used laser scanner and DSLR as well as smart phone photography to derive reference values to enable verifying the spatial model obtained from the web-album images. The investigation shows how detailed and accurate models could be derived applying photogrammetric processing software, simply by using images of the community, without visiting the site.

Environmental, engineering and industrial modelling of natural features (e.g. trees) and man-made features (e.g. pipelines) requires some form of fitting of geometrical objects such as cylinders, which is commonly undertaken using a least-squares method thatin order to get optimal estimationassumes normal Gaussian distribution. In the presence of outliers, however, this assumption is violated leading to a Gaussian mixture distribution. This study proposes a robust parameter estimation method, which is an improved and extended form of vector algebraic modelling. The proposed method employs expectation maximisation and maximum likelihood estimation (MLE) to find cylindrical parameters in case of Gaussian mixture distribution. MLE computes the model parameters assuming that the distribution of model errors is a Gaussian mixture corresponding to inlier and outlier points. The parameters of the Gaussian mixture distribution and the membership functions of the inliers and outliers are computed using an expectation maximisation algorithm from the histogram of the model error distribution, and the initial guess values for the model parameters are obtained using total least squares. The method, illustrated by a practical example from a terrestrial laser scanning point cloud, is novel in that it is algebraic (i.e. provides a non-iterative solution to the global maximisation problem of the likelihood function), is practically useful for any type of error distribution model and is capable of separating points of interest and outliers.

Pedestrian flow is much less regulated and controlled compared to vehicle traffic. Estimating flow parameters would support many safety, security or commercial applications. Current paper discusses a method that enables acquiring information on pedestrian movements without disturbing and changing their motion. Profile laser scanner and depth camera have been applied to capture the geometry of the moving people as time series. Procedures have been developed to derive complex flow parameters, such as count, volume, walking direction and velocity from laser scanned point clouds. Since no images are captured from the faces of pedestrians, no privacy issues raised. The paper includes accuracy analysis of the estimated parameters based on video footage as reference. Due to the dense point clouds, detailed geometry analysis has been conducted to obtain the height and shoulder width of pedestrians and to detect whether luggage has been carried or not. The derived parameters support safety (e.g. detecting critical pedestrian density in mass events), security (e.g. detecting prohibited baggage in endangered areas) and commercial applications (e.g. counting pedestrians at all entrances/exits of a shopping mall).

Several scientific papers suggest that microbial transglutaminase (mTG) is capable of reducing the salt content of cured and/or heat-treated meat products (ham, frankfurters, meat ball). These scientific results are not widely known in Hungary, and as a result of this, only little experience was gathered in our meat industry. According to this lack of knowledge, our aim was to lower the curing salt to a still microbiological safe level using mTG by frankfurters, one of the most well-known heat treated meat products in Hungary. The observed technofunctional properties suggest to use mTG enzyme preparation at 0.5% concentration. This enzyme dosage can reduce the average 1.8% salt content to 1.6% and it also may contribute to extended shelf life of popular frankfurters. Our sensorial analysis revealed that the panellists have not found a loss in quality between 1.4% and 1.6% salt.

In this paper, the use of waveform data in urban areas is studied. Full waveform is generally used in non-urban areas, where it can provide better vertical structure description of vegetation compared to discrete return systems. However, waveform could be potentially useful for classification in urban areas, where classification methods can be extended to include parameters derived from waveform analysis. Besides common properties, also sensed by multi-echo systems (intensity, number of returns), the shape of the waveform also depends on physical properties of the reflecting surface, such as material, angle of incidence, etc. The main goal of this investigation is to identify relevant parameters, derived from waveform that are related to surface material or object class. This paper uses two waveform parameterization approaches: Gaussian shape fitting and discrete wavelet transformation. The two classification methods tested are: supervised Bayes classification and unsupervised Self-Organizing Map (SOM) classification. The results of these methods were compared to each other and to manual classification. The initial conclusion is that, though waveform data contains classification information, the waveform shape by itself is not enough to perform classification in urban regions, and, consequently, it should be combined with the point cloud geometry.

Flash LiDAR systems have been around for several years, but their use was limited, mainly due to their poor performance. The first generation products had range limitations and were quite sensitive to ambient light conditions, basically restricting their use to indoor applications. In addition, the high-noise level provided for very low accuracy and stability. As technology advanced, the Flash LiDAR sensors have shown gradual improvements in performance, resulting in an increasing number of applications. One of the most recently introduced inexpensive sensors is the Microsoft Kinect, originally designed to support gaming. Despite its low cost, the Kinect is very powerful, providing a relatively dense point cloud and high-definition video at high data rate. This paper reports about our investigation with this sensor, including calibration experiences and performance evaluation.

This paper provides an update on the continuing research effort focused on creating a collaborative navigation solution of various multi-sensory platforms for indoor, outdoor, and transitional environments. The emphasis of this paper is to investigate the usefulness of 3D imagery, taken from optical or laser sensors, in aiding indoor cooperative navigation of multi-sensory pedestrian platforms. Data characterization is provided and performance of the Microsoft Kinect (TM) sensor is evaluated. In addition, indoor navigation test results using 3D image-based navigation and the potential of the Kinect for identification and ranging between platforms are discussed.