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• Recognition of liquid–gas flow regime in horizontal pipeline. • Sealed Am-241 gamma ray sources and NaI(TI) scintillation detectors were used. • Eight features for fluid flow were extracted by signal analysis in the frequency domain. • Six computational intelligence methods were employed to identify the flow regime. • All of the methods provided good classification results for the analyzed liquid–gas flow. Two-phase liquid–gas flows are common in industries such as mining, energy, chemicals, and oil. The gamma-ray absorption technique is a non-contact method widely used to measure parameters for such flows. By analyzing signals from scintillation detectors, flow parameters can be determined and flow structures identified. This study evaluated four types of water–air flow regimes using selected computational intelligence methods. The experiments involved a water–air flow in a horizontal pipe with a 30 mm internal diameter, using two sealed Am-241 gamma ray sources and two scintillation probes type NaI(Tl). Eight features for fluid flow were extracted from the power spectral density and the cross-spectral density of the obtained measurement signals and then used as input for the classifier. Six computational intelligence methods, including k-means, a single decision tree, a support vector machine, a probabilistic neural network, a multilayer perceptron, and a radial basis function, were applied to identify the flow regime. The results showed that all of the methods provided good results of classification for the analyzed types of water–air flow. [ABSTRACT FROM AUTHOR]

Cities are expanding rapidly and emerging as complex ecosystems. This expansion of urbanized areas has resulted in the alteration and fragmentation of several natural habitats. Recent studies have shown that cities support a significant level of biodiversity. This unexpected role of cities holds promise for advancing knowledge of urban ecosystems and promoting their conservation. In particular, the connectivity of plant populations through pollen transfer is crucial for the long-term persistence of insect-pollinated plant species. In this study, we tracked pollen movement areas in four isolated patches of urban greenery in urbanized area using quantum dots. We studied Fritillaria imperialis (spring) and Hemerocallis sp. (mid-summer). Our research revealed frequent pollen transfer between small, isolated flowering patches, even when these locations were not connected by green corridors. Common elements found in urban ecosystems, such as streets, trails, and pavements, do not stop the dispersion of pollen grains. Moreover, the migration pathways of pollen grains vary for each species according to different factors. For F. imperialis , we identified the proportion of green areas in proximity to the study location as a key factor in shaping pollen transfer. For Hemerocallis , we discovered that the proportion of green areas, the distance between study sites, and the frequency of pollinator visits are influential factors. Our study demonstrates that small isolated plant populations exchange pollen due to pollinator movement, indicating that these small populations may serve as stepping stones for pollinators among larger populations. • We showed that pollinators move among isolated green areas in the cities. • Pollinators movements vary within the seson • In isolated urban population of flowering plants pollinators move mostly within population. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Investigation of liquid-gas flow in a horizontal pipe using gamma-ray absorption. • Measurements of the time delay and dispersed phase velocity using cross-correlation. • Analysis of distortions of signals obtained from scintillation detectors. • Application of four methods in the time and frequency domain for noise reduction. Abstract Two-phase liquid-gas flows occur frequently in the mining, energy, chemical, and petrochemical industries. One of non-contact methods used to analyse these flows is the gamma ray absorption method. However, the signals received from radiation detectors contain a significant stochastic noise, which makes them difficult to analyse. The article describes four methods of noise reduction in cross-correlation measurements of water-air mixture flows in a horizontal pipeline. In addition to the classical method of digital filtering of signals, the methods consisting in signal spectrum filtering, discrete wavelet transformation, and Nadaraya-Watson kernel estimator are described. Sample results of the measurements carried out in the horizontal pipe having the inner diameter of 30 mm for the air bubbles velocity ranging from 0.7 to 1.4 m/s are presented. In the research, the absorption set composed of two linear Am-241 gamma-ray sources and two scintillation NaI(Tl) probes was used. It was found that the lowest measurement uncertainty of the dispersed phase flow velocity is obtained when the cross-correlation distributions of the recorded signals are smoothed using the Discrete Wavelet Transform or the Nadaraya-Watson kernel estimator. [ABSTRACT FROM AUTHOR]

Liquid-gas flows in pipelines occur frequently in the mining, nuclear, and oil industry. One of the non-contact techniques useful for studying such flows is the gamma ray absorption method. An analysis of the signals from scintillation detectors allows us to determine the number of flow parameters and to identify the flow structure. In this work, four types of liquid-gas flow regimes as a slug, plug, bubble, and transitional plug – bubble were evaluated using computational intelligence methods. The experiments were carried out for water-air flow through a horizontal pipeline. A sealed Am-241 gamma ray source and a NaI(Tl) scintillation detector were used in the research. Based on the measuring signal analysis in the time domain, nine features were extracted which were used at the input of the classifier. Six computational intelligence methods (K-means clustering algorithm, single decision tree, probabilistic neural network, multilayer perceptron, radial basic function neural network and support vector machine) were used for a two-phase flow structure identification. It was found that all the methods give good recognition results for the types of flow examined. These results confirm the usefulness of gamma ray absorption in combination with artificial intelligence methods for liquid-gas flow regime classification. [ABSTRACT FROM AUTHOR]

Pollination is a key ecological service for human food security and the reproduction of the majority of flowering plants. This plant-animal interaction is crucial in both wild and urban habitats, however, increasing urbanization and change in land use alter these interactions. The concerns regarding pollination have led to numerous efforts aimed at improving the quality of wildlife in cities, however, understanding the importance of these activities warrants further research. In Warsaw, the Polish capital, we analyzed the influence of urban-related factors such as floral resource richness, the proportion of green areas in the proximity of foraging sites, air pollution or temperature on plant-pollinator interaction in 14 meadows. We also analyzed the reproductive success and the heterospecific pollen transfer in the case of plants growing in the meadows. Our study revealed that the frequency of visits to flowers was related to city-related factors, but the reaction varied among different groups of pollinators. For example, bumblebees were negatively influenced by higher air pollution, while the rest of the flower visitors were not, Syrphidae flies were more frequent flower visitors when the proportion of green area was higher in the buffer of 150 m, while we did not observe this tendency in other groups of flower visitors. Plants growing in Warsaw meadows were frequently visited and effectively pollinated - urban pollinator assemblages seem to provide sufficient pollination services to plants growing in the city. Species-rich communities were not a threat to pollination; we found mostly conspecific pollen grains on the stigmas of the studied plant species. The results of our study show that species-rich communities make a valuable contribution to pollinator conservation. The conservation activities, however, should be adjusted to the target group of pollinators, since different groups of flower visitors respond differently to urban-related factors studied. • Urban pollinators assemblages are efficient pollinators – plants growing on urban meadows were not pollen limited. • Bumblebees activity was influenced by higher air pollution. • Syrphidae flies were more frequent flower visitors when the proportion of green area was higher in the buffer of 150 m. • Species-rich communities were not a threat to pollination of common urban plant species. [ABSTRACT FROM AUTHOR]

The article discusses a study on hydrotransport of solid particles (ceramic models of polymetallic nodules) in a vertical pipeline using two different radioisotope methods: tracer and gamma-ray absorption. The radiotracer method makes it possible to determine the velocity of selected solid particles representing specified size fractions while the absorption method enables measurement of mean transport velocity of the entire dispersed phase. The measurements were performed with the use of NaI(Tl) scintillation detectors, sealed linear sources of radiation Am-241 with the energy of 59.54 keV and isotope Tc-99m with gamma radiation energy of 140.51 keV. The experiments were carried out in a pipeline with an internal diameter of 150 mm, for three different water velocities in the range of 1.5–3.6 m/s and three different sizes of ceramic models with size up to 60 mm. Analyses of the detector signals, in measurements based on both tracer and absorption technique, applied cross-correlation function (CCF). It was shown that with the same water velocity different fractions of solid particles have moved with different velocities and the lowest velocities were obtained for the particles with the largest diameters. This enabled interpretation of the CCF in absorption measurements as a distribution of possible interval times for the specific fractions of conveyed particles. [ABSTRACT FROM AUTHOR]

The design of radiation measurement systems includes a modelling phase which ascertains the best 3D geometry for a projected gauge. To simulate measured counts by a detector, the widely-used rigorous phenomenological model is used. However, this model does not consider possible source or/and detector movement during a measurement interval. Therefore, the phenomenological model has been successfully modified in order to consider such a displacement during the time sampling interval in dynamic experiments. To validate the proposed model, a simple radiation system was accurately implemented in the MCNP5 code. The experiments confirmed the accuracy of the proposed model. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents possibilities for use of gamma-ray sealed sources for analysis of two-phase compound flows in an open channel as an example of a mud slurry suspension hydrotransport investigation. The objective of the research was to model the Flysch Carpathian formation as a result of the suspension stream and measurements of slurry flow rate. Due to the specific properties of muds the gamma-ray absorption and ultrasonic methods were used for flow measuring and the correlation analysis was applied to the recorded signals. The constructed testing installation was described in details and examples of measurement results were given. The obtained data allow the vertical solid particle velocity distribution in a channel to be determined. That information facilitated with the additional photo documentation enables the forming geological structures to be identified. [Copyright &y& Elsevier]

Detailed studies of the floral anatomy, morphology, ultrastructure, and the occurrence of floral food-rewards in Bulbophyllum are rare. Here, we investigate the structure of the labellum and secretion of labellar food-rewards for ten Asian species of the genus, representing six sections. Labellar tissue of each of these species was examined using LM, SEM, and TEM, and compared with our previous results for representatives of sect. Racemosae and two African species of Bulbophyllum . The study indicated that only members of sections Sestochilos and Stenochilus produced true nectar, and this was present on the adaxial surface of sepals. Lipids occurred only in the labellar secretions of members of sect. Recurvae. In members of sections Sestochilos, Brachyantha and Desmosanthes , labellar secretion was absent. In most investigated sections, secretion, if present, was produced by relatively unspecialized epidermal cells lining a median labellar groove. The labella of most sections contained both ground parenchyma and aerenchyma. This study demonstrates, in conjunction with the results of previous studies, that the structure of the labellum in this genus is highly diverse, especially with respect to the labellar adaxial epidermis, which represents various degrees of secretory specialization. [ABSTRACT FROM AUTHOR]

Developing technology for the deep-sea mining of polymetallic nodules requires, theoretical analyses, simulation and numerous experimental studies. In this paper authors focused on nuclear methods adoption to velocity of solid phase measurement in an extremely hard and varying environment. Selected results of the experimental studies of two-phase liquid–solid particles flow in a vertical pipeline obtained by probing with photon beams are presented. With the use of the sealed 241 Am isotopes emitting gamma radiation of 59.5 keV, and the scintillation probes with NaI(TI) detectors, the average transport velocity for ceramic models representing natural polymetallic nodules were determined. In the paper for analysis of the signals coming from the probes, the cross correlation function (CCF) and its modifications consisting in the combination of the CCF with such procedures as the average square difference function (ASDF) and the average magnitude difference function (AMDF) were used. An example of measurement is presented and its resulting uncertainties determined. In described experiment the relative values of the combined uncertainty of solid particles average velocity estimation are equal to: 3.2% for the CCF, 3.0% for the CCF/AMDF and 2.8% for the CCF/ASDF. [ABSTRACT FROM AUTHOR]

The article presents an estimation of measurement uncertainty of a liquid mass flow using the orifice plate. This subject is essential because of the widespread use of this type of flow meters. Not only the quantitative estimation but also the qualitative results of those measurements are important. To achieve these results the authors of the paper propose to use the theory of uncertainty. The article shows the analysis of the measurement uncertainty using two methods: one based on the ‘Guide to the expression of uncertainty in measurement’ (GUM) of the International Organization for Standardization by means of the law of propagation of uncertainty, and the second one by means of the Monte Carlo numerical method. The paper presents a comparative analysis of the results obtained by employing both of these methods for the centric and eccentric orifice plate. In both of the examples, the resulting uncertainty of flow measurement is approximately 1%. The uncertainty determined by the analytical method was higher than what was obtained from the Monte Carlo simulations with a difference of 0.04%. [ABSTRACT FROM AUTHOR]

• Research on a prototype 4-hole orifice with module m = 0.25. • CFD modeling for two turbulence models: k - ε -realizable and k -ω- BSL. • A high accuracy numerical model was developed for Re = 4200–19,000. • The experimental results for volumetric flows in range 0.167–0.686 dm3/s. • Numerical simulations for multihole orifice flowmeter. • The experimental research was found to be very compatible with simulations. In this research study, the comprehensive metrological analysis is investigated for a 4-hole orifice with module m = 0.25 installed in the pipeline with an internal diameter of 50 mm. A detailed numerical simulation was performed for the turbulence models: k-ε-realizable and k- ω -BSL. The novelties of the research include model validation by comparing the results of numerical studies with the experiment conducted in the area of developing turbulent flow in the range of Reynolds numbers from 4,200 to 19,000. Such validated models are sought by the system designers and can be used for further analyses and optimisation of this orifice in this flow type. The multi-hole orifices are less sensitive to flow disturbances than the standardized standard centric orifice. In addition, orifices of this type can be mounted in installations with much shorter sections upstream and downstream of the orifice - which is very often the case in industrial flow installations. [ABSTRACT FROM AUTHOR]

• Mass flow rate measurement using a segmental orifice with a module m = 0.25. • The flow type analysis for Reynolds numbers Re = 9,000 to 17,000. • Monte Carlo simulations and experiments on the laboratory stand were conducted. • The resulting relative uncertainty of flow rate measurement does not exceed 1.8% for the tested orifice. Segmental orifices are often used to measure flows of heterogeneous mixtures, especially in flow meters in the power industry, for example. The orifice (with module m = 0.25) was installed in a stainless-steel pipe with internal diameter of 50 mm, placed in a hydraulic water system. The research was performed for Reynolds numbers ranging from 9,000 to 17,000. The flow characteristics of this orifice obtained based on simulation in SolidWorks Flow Simulation 2014 and experimental data were compared with standard-based calculations. It was determined that relative differences between the obtained flow characteristics did not exceed 1.5% for the experiment and 5.1% for the simulation. The article also presents the results of estimated uncertainty for mass flow measurement q m using the analytical method and the Monte Carlo simulations. The results for both methods proved that the relative expanded uncertainty U rel (q m) does not exceed 1.8% for the tested orifice. [ABSTRACT FROM AUTHOR]

• Mass flow rate measurement using a centric and eccentric orifice with diameter ratio ß = 0.5. • Analysis of the impact of the flow type (for Reynolds numbers Re = 10,000 ... 20,000) on the flow rate measurement uncertainty. • Comparison of the impact of the type of orifice used on the uncertainty of flow rate measurement. • Monte Carlo simulations and experiments on the laboratory stand were used. • The resulting relative uncertainty of flow rate measurement does not exceed 2.1% for both orifice types. The article analyses the impact of the Reynolds number on the estimated uncertainty of the mass flow rate measurement using an orifice plate. The objects of the research were two types of orifices: centric (ISA) and eccentric, with the diameter ratio β = 0.5. Studies were performed by Monte Carlo simulation and experiments for Reynolds numbers in the range 10,000 ≤ Re ≤ 20,000. The obtained results have shown that for both orifice types, the results obtained from the experiments and from the Monte Carlo simulation are similar. The nature of changes in the expanded uncertainty of the flow measurement is very similar for each type. For the both types of orifices, the value of the expanded uncertainty of the flow measurement increases linearly with the increasing Reynolds number. [ABSTRACT FROM AUTHOR]