rss_2.0Geosciences FeedSciendo RSS Feed for Geosciences Feed and Antibiogram of Bacterial Species in Litter of Selected Poultry Farms in Idi-Ayunre Community, Oyo State, Nigeria<abstract> <title style='display:none'>Abstract</title> <p>The misuse and overuse of antibiotics within poultry sector of the animal agriculture threatens public health due to its aftermath effect arising from the release of resistant pathogens to the environment. This study investigated the prevalence and antimicrobial susceptibility status of bacterial species isolated from litter of selected poultry farms within Idi Ayunre, a poultry-dense community in Oyo State. Poultry droppings (5 g) was collected each from six (6) randomly selected farms and bacteria isolated using Brain Heart Infusion agar (BHI), MacConkey agar (MCA), Eosin methylene blue agar (EMB) and Salmonella Shigella agar (SSA) media respectively via pour plate technique. Bacterial isolates were identified via morphological and biochemical tests and their antibiotic susceptibility pattern determined via Kirby-Bauer disc diffusion method using multi-disc antibiotics. Farm A had highest Total Heterotrophic Count (THC, 8.43 Log<sub>10</sub>CFU/mL) and Total Enterobacteriaceae Count (TEC, 6.32 Log<sub>10</sub>CFU/mL). However, Farm C had lowest THC and TEC (7.18 Log<sub>10</sub>CFU/mL and 4.48 Log<sub>10</sub>CFU/mL respectively), while Farm B had lowest Total Coliform Count (TCC, 4.70 Log<sub>10</sub>CFU/mL) with the highest being Farm D (6.08 Log<sub>10</sub>CFU/mL). Also Farm D had the highest (8.15 Log<sub>10</sub>CFU/mL) Salmonella-Shigella Count (SSC) with Farm E having the lowest (4.85 Log<sub>10</sub>CFU/mL). Isolates obtained were identified as <italic>Staphylococcus aureus, Proteus</italic> sp., <italic>Bacillus</italic> sp., <italic>Pseudomonas</italic> sp, <italic>Klebsiella</italic> sp., <italic>Escherichia coli, Citrobacter</italic> sp., <italic>Salmonella</italic> sp., <italic>Enterobacter</italic> sp. and <italic>Shigella</italic> sp. Across the farms, <italic>S. aureus, Bacillus</italic> sp. and <italic>E. coli</italic> were isolated, while <italic>Shigella</italic> sp. was isolated only from Farm D. The bacteria isolates were found to be multidrug resistant towards the tested antibiotics, showing susceptibility only to gentamicin and ofloxacin. This study therefore showed that birds’ droppings from poultry farms in Idi Ayunre community serve as carrier of multidrug resistant pathogens. Hence, the need for a cautious use of antibiotics among Idi Ayunre poultry farmers.</p> </abstract>ARTICLE2022-08-15T00:00:00.000+00:00Assessment of Soil Characteristics Using a Three-Band Agricultural Digital Camera<abstract> <title style='display:none'>Abstract</title> <p>Remote sensing techniques based on soil spectral characteristics are the key to future land management; however, they still require field measurement and an agrochemical laboratory for the calibration of the soil property model. Visible and near-infrared diffuse reflectance spectroscopy has proven to be a rapid and effective method. This study aimed to assess the suitability of multispectral data acquired with the agricultural digital camera in determining soil properties. This 3.2-Mpx camera captures images in three spectral bands – green, red and near-infrared. First, the reference data were collected, which consist of 151 samples that were later examined in the laboratory to specify the granulometric composition and to quantify some chemical elements. Second, additional soil properties such as cation exchange capacity, organic carbon and soil pH were measured. Finally, the agricultural digital camera photograph was taken for every soil sample. Reflectance values in three available spectra bands were used to calculate the spectra indices. The relationships between the collected data were calculated using the independent validation regression model such as Cubist and cross-validation model like partial least square in R Studio. Additionally, different types of data normalisation multiplicative scatter correction, standard normal variate, min–max normalisation, conversion into absorbance] were used. The results proved that the agricultural digital camera is suitable for soil property assessment of sand and silt, pH, K, Cu, Pb, Mn, F, cation exchange capacity and organic carbon content. Coefficient of determination varied from 0.563 (for K) to 0.986 (for soil organic carbon). Higher values were obtained with the Cubist regression model than with partial least squares.</p> </abstract>ARTICLE2022-08-11T00:00:00.000+00:00Formation and role of neogene sediments from Tatra mountains in the shaping of Czarna Orawa river alluvial plain<abstract> <title style='display:none'>Abstract</title> <p>. The paper presents researches that were conducted in Czarna Orawa River catchment, situated within the Tatra and Beskidy Mountains. Czarna Orawa River channel is segmental meandering system with the index of tortuosity up to 1.6. The aim of the article is to characterize gravels which were transported from the Tatra Mountains and their role in valley bottom formation.</p> </abstract>ARTICLE2012-10-21T00:00:00.000+00:00A Novel Fault Diagnosis Method for Marine Blower with Vibration Signals<abstract> <title style='display:none'>Abstract</title> <p>The vibration signals on marine blowers are non-linear and non-stationary. In addition, the equipment in marine engine room is numerous and affects each other, which makes it difficult to extract fault features of vibration signals in the time domain. This paper proposes a fault diagnosis method based on the combination of Ensemble Empirical Mode Decomposition (EEMD), an Autoregressive model (AR model) and the correlation coefficient method. Firstly, a series of Intrinsic Mode Function (IMF) components were obtained after the vibration signal was decomposed by EEMD. Secondly, effective IMF components were selected by the correlation coefficient method. AR models were established and the power spectrum was analysed. It was verified that blower failure can be accurately diagnosed. In addition, an intelligent diagnosis method was proposed based on the combination of EEMD energy and a Back Propagation Neural Network (BPNN), with a correlation coefficient method to get effective IMF components, and the energy components were calculated, normalised as a feature vector. Finally, the feature vector was sent to the BPNN for training and state recognition. The results indicated that the EEMD-BPNN intelligent fault diagnosis method is suitable for higly accurate fault diagnosis of marine blowers.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Evaluating an Inland Waterway Cargo Vessel’s Energy Efficiency Indices<abstract> <title style='display:none'>Abstract</title> <p>Although the International Maritime Organization (IMO) introduced the energy efficiency requirements for ships more than a decade ago, to date, inland navigation has not been affected by corresponding regulations at all. Therefore, inland waterway vessels are left with no mandatory requirements that could push their technology into more energy efficient design. Fortunately, there are certain pioneering attempts to define energy efficiency criteria for inland vessels. This paper tries to gather and provide a review of such methods. Moreover, a typical Danube cargo inland vessel’s data are used to evaluate their current energy efficiency levels with respect to provisional criteria. Consequently, two methods are found and used here. They are both based on IMO’s energy efficiency concept but modified for the inland waterway vessels. The methods delivered a significant difference in applicability and were difficult to compare. Moreover, shallow and deep-water effects are explored in the same regard but provided unsound conclusions. The final results displayed discrepancies in energy efficiency levels for the same vessels and so the methodology should be improved and harmonised, if it is to be introduced as mandatory for inland waterway vessels. The analysis provided a glimpse into the current condition of the traditional design of the Danube inland fleet, with respect to the emerging energy efficiency policies.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Analysis of the Hydrodynamic Properties of the 3-Column Spar Platform for Offshore Wind Turbines<abstract> <title style='display:none'>Abstract</title> <p>The article presents a design of a floating platform for offshore wind turbines. The concept is a modification of the Spar design and consists of three variable section columns connected to each other by a ballast tank in the lower part of the platform. This solution makes it possible to influence the position of the centre of buoyancy and the centre of mass of the structure. Compared to the classic Spar platform structure, the centre of buoyancy can be higher than mid-draft, which will provide the platform with greater stability. At the same time, this concept is better, in terms of technology, because of its modular structure and smaller bending radii.On the basis of the model testing performed, the hydrodynamic coefficients of the designed platform and its response to a given regular wave were determined (the transfer functions for heave and pitch motion were determined). Then, based on the damping coefficients, the platform was modelled in the ANSYS AQWA program and the results were very similar.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Navigation Situation Assessment of Autonomous Surface Vehicles in a Cooperative Hunting Environment<abstract> <title style='display:none'>Abstract</title> <p>This paper proposes a navigation situation assessment method for autonomous surface vehicles (ASVs) in a cooperative hunting environment. By virtue of the repulsion function expressed in the artificial potential field, the navigation situation of hunting ASVs and target ASVs is firstly described. And the hunting situation is also constructed to describe the cooperative hunting. Based on the navigation situation and the hunting situation, a navigation situation assessment method for cooperative hunting of multiple ASVs is designed, where the number of hunting vehicles and the hunting radius can be successfully computed. Simulation results show that this proposed situation assessment method can give an optimised formation pattern and provide an effective reference for cooperative hunting of ASVs.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Investigation of the Characteristics of a Low-Emission Gas Turbine Combustion Chamber Operating on a Mixture of Natural Gas and Hydrogen<abstract> <title style='display:none'>Abstract</title> <p>This article is devoted to the investigation of the characteristics of a low-emission gas turbine combustion chamber, which can be used in Floating Production, Storage and Offloading (FPSO) vessels and operates on a mixture of natural gas and hydrogen. A new approach is proposed for modelling the processes of burning out a mixture of natural gas with hydrogen under preliminary mixing conditions in gaseous fuel with an oxidizer in the channels of radial-axial swirlers of flame tubes. The proposed kinetic hydrocarbon combustion scheme is used in three-dimensional calculations for a cannular combustion chamber of a 25 MW gas turbine engine for two combustion models: the Finite-Rate/Eddy-Dissipation and the Eddy Dissipation Concept. It was found that, for the investigated combustion chamber, the range of stable operations, without the formation of a flashback zone in the channels of radial-axial swirlers, is determined by the hydrogen content in the mixture, which is less than 25-30% (by volume). For the operating modes of the chamber without the formation of a flashback zone inside the swirler channels, the emissions of nitrogen oxide NO and carbon monoxide CO do not exceed the values corresponding to modern environmental requirements for emissions of toxic components by gas turbine engines.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Effects of Rudder and Blade Pitch on Hydrodynamic Performance of Marine Propeller Using CFD<abstract> <title style='display:none'>Abstract</title> <p>The use of computational fluid dynamics (CFD) to predict internal and external flows has risen dramatically in the past decade. This research aims to use the commercial software, ANSYS Fluent V.14.5, to illustrate the effects of the rudder and blade pitch on the hydrodynamic performance of the marine propeller by experimenting with propellers and rudders of the M/V Tan Cang Foundation ship, which has designed conditions as follows: diameter of 3.65 m; speed of 200 rpm; average pitch of 2.459 m; boss ratio of 0.1730. Using CFD, the characteristic curves of the marine propeller and some important results showed that the maximum efficiency of the propeller is 0.66 with the open water propeller and 0.689 with the rudder‒propeller system at the advance ratio of 0.6. The obtained outcomes of this research are a significant foundation to calculate and design an innovative kind of propulsion for ships with high performance.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Analysis of Marine Risers Subjected to Shoal/Deep Water in the Installation Process<abstract> <title style='display:none'>Abstract</title> <p>The dynamics of the installation process of marine risers subjected to shoal/deep seawater is studied. The riser is assumed to be a cantilevered Euler‒Bernoulli beam. The upper end of the riser is clamped on the vessel or the drilling platform. The lower end of the riser is connected to the Blowout Preventer Stack (BOPs) and Lower Marine Risers Package (LMRP). The lateral fluid forces induced by the sea wave and sea current are introduced into the governing equations of motion. The lateral displacement and stress distributions of the riser are obtained by solving the governing equation of the riser via Galerkin’s discretisation scheme and a fourth-order Runge‒Kutta algorithm. The results indicate that the riser exhibits different behaviours under various depths because of the different distributions of the flow velocity ranging from the sea surface to the seabed. In the case of shoal water, the dynamics of the riser are dominated by the sea wave, while in the case of deep water it is affected mainly by the sea current velocity and sea surface wind velocity.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:0050’ Sail Catamaran with Hybrid Propulsion, Design, Theoretical and Experimental Studies<abstract> <title style='display:none'>Abstract</title> <p>The development of modern lithium batteries and propulsion systems now allows the use of complex propulsion systems for vessels of various sizes. As part of the research and implementation project, a parallel hybrid drive system was designed, built and then tested in the laboratory. The experimental studies conducted allowed for the measurements of power, fuel consumption and electric power distribution in various operating modes of the propulsion system. The research proves that in the analysed case, the hybrid parallel system meets the demand for electric energy during a typical cruise scenario, and thus there is no need to install a power generator on the yacht.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Design Wave Calculation of a Passenger Catamaran Under Multiple Load Control Parameters<abstract> <title style='display:none'>Abstract</title> <p>To determine the loading conditions considering the action of both bending and torque moment for a passenger catamaran moving among waves, a method for calculating equivalent design waves under multiple load control parameters was derived based on wave load prediction results using three-dimensional potential flow theory. The method was developed by defining the wave amplitude discrepancy factors between the primary and second load of the combined bending and torquing equivalent design wave. The primary goal was to find a reasonable design wave. Finally, the design waves of a target passenger catamaran ship were calculated using the proposed method, and each load component of every design wave for the target hull was recalculated. The average error compared with the object load component was less than 1%, which verifies the effectiveness of the method and offers an effective engineering evaluation method for a catamaran.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Weather Routing System Architecture Using Onboard Data Collection and Route Optimisation<abstract> <title style='display:none'>Abstract</title> <p>This paper describes the architecture of a weather routing system consisting of two key elements: onboard monitoring and route optimiser sub-systems. The former is responsible for collecting various onboard measurements, such as current ship position or ship motion variables. These data, when gathered and processed, are then used for fine-tuning a ship model. The model, together with weather forecasts, is utilised by a multi-objective route optimiser to estimate forecasted ship responses during the voyage. The route optimiser has been developed in a client-server architecture to reallocate all necessary high-tech resources to the server side and keep the client software as simple and light as possible. The system also includes a module responsible for optimising transmission costs, to reduce onboard transmission during the voyage. The entire solution has been deployed onboard the demonstrator ship ‘Monte da Guia’ and tested during its operations at sea.</p> </abstract>ARTICLE2022-08-05T00:00:00.000+00:00Israel’s changing geostrategic posture<abstract> <title style='display:none'>Abstract</title> <p>This paper analyzes Israel’s changing understanding of its geostrategic posture from its establishment in 1948 to the current era. It starts by reviewing traditional Israeli geostrategic ideas and their implementation, mostly, as reflected in the nation’s national security doctrine. The paper then investigates the effect of Israel’s territorial expansion after 1967 on Israeli ideas about geostrategy. Finally, the paper shows how changing global, regional, and technological variables in the last two decades have transformed how Israeli elites understand their geostrategic realities and how they allocate resources in response to these changing conditions.</p> </abstract>ARTICLE2022-08-01T00:00:00.000+00:00 and its undisturbed forefield relief, Eastern Pamir, Tajikistan<abstract> <title style='display:none'>Abstract</title> <p>The surge-type Uisu glacier and its forefield in the Tajik part of Eastern Pamir are described. To this end, 1977–2019 Landsat satellite imagery, the DEM, and a high-resolution orthophotomap were used, and detailed geomorphological mapping was carried out. The results show that the present-day position of the terminus of the studied glacier results from a surge that occurred before 1947. Currently, the glacier is losing mass. However, despite the visible characteristics of its thawing, the extent of the terminal zone has remained stable for several decades. Outside the glacier, there are no glacial landforms. This indicates that advances of surging glaciers may not create any surge-diagnostic features in their forefields. On the other hand, the genesis and interactions of landforms can reveal glacier surge, even in the absence of terminal and lateral glacial landforms.</p> </abstract>ARTICLE2022-07-31T00:00:00.000+00:00A Script-Driven Approach to Mapping Satellite-Derived Topography and Gravity Data Over the Zagros Fold-and-Thrust Belt, Iran<abstract> <title style='display:none'>Abstract</title> <p>Integrated geophysical mapping benefits from visualizing multi-source datasets including gravity and satellite altimetry data using 2D and 3D techniques. Applying scripting cartographic approach by R language and GMT supported by traditional mapping in QGIS is presented in this paper with a case study of Iranian geomorphology and a special focus on Zagros Fold-and-Thrust Belt, a unique landform of the country affected by complex geodynamic structure. Several modules of GMT and ’tmap’ and ’raster’ packages of R language were shown to illustrate the efficiency of the console-based mapping by scripts. Data sources included high-resolution raster grids of GEBCO/SRTM, EGM-2008, SRTM DEM and vector geologic layers of USGS. The cartographic objective was to visualize thematic maps of Iran: topography, geology, satellite-derived gravity anomalies, geoid undulations and geomorphology. Various cartographic techniques were applied to plot the geophysical and topographic field gradients and categorical variations in geological structures and relief along the Zagros Fold-and-Thrust Belt. The structures of Elburz, Zagros, Kopet Dag and Makran slopes, Dasht-e Kavir, Dasht-e Lut and Great Salt Desert were visualized using 3D-and 2D techniques. The geomorphometric properties (slope, aspect, hillshade, elevations) were modelled by R. The study presented a series of 11 new maps made using a combination of scripting techniques and GIS for comparative geological-geophysical analysis. Listings of R and GMT scripting are provided for repeatability.</p> </abstract>ARTICLE2022-07-28T00:00:00.000+00:00A regional scale Cretaceous transform fault zone at the northern Austroalpine margin: Geology of the western Ammergau Alps, Bavaria<abstract> <title style='display:none'>Abstract</title> <p>We reinvestigated parts of the northern Austroalpine margin and provided structural and kinematic field data in order to interpret the kinematic relationship between the Cenoman-Randschuppe (CRS) marginal slice, Falkensteinzug (FSZ), Tannheim- and Karwendel thrust sheets occurring in a narrow strip at the northern front of the northwestern Northern Calcareous Alps (NCA). As a consequence, we propose a revised model for the tectonic evolution of the northern Austroalpine margin. As thrusting propagates from SSE to NNW (Cretaceous orogeny), the Karwendel thrust sheet (including its frontal part, the FSZ) was emplaced onto the Tannheim thrust sheet in the Albian, deduced from (i) upper-footwall deposits, the youngest sediments below the Karwendel thrust (Tannheim- and Losenstein Fms.), and (ii) thrust-sheet-top deposits unconformably overlying the deeply eroded northern Karwendel thrust sheet (Branderfleck Fm.). The future CRS marginal slice was, at that time, part of the foreland of this Early Cretaceous Alpine orogenic wedge. Pervasive overprint by sinistral shear within the CRS marginal slice and northern Tannheim thrust sheet suggests sinistral W-E striking transform faults cutting across this foreland, decoupling CRS marginal slice and FSZ from the main body of the NCA and enabling an independent evolution of the CRS marginal slice from the Early Cretaceous onwards. Subsequent Late Cretaceous and younger shortening leads to successive incorporation of Arosa zone, Rhenodanubian Flysch (RDF) and Helvetic units into the Alpine nappe stack; the Tannheim thrust representing the basal thrust of the NCA. Growth strata within thrust-sheet-top deposits (Branderfleck-Fm.) give evidence for refolding of thrust sheet boundaries. In a typical thin-skinned fold-and-thrust belt, deformation should cease towards the thrust front, whereas within the NCA it increases. An Austroalpine thrust front controlled by E-trending transform faults could cause an increase in deformation towards the most external NCA and explain the absence of the Arosa zone between Allgäu and Vienna. Such faults would most probably also cut out Lower Austroalpine units. Therefore, RDF and CRS marginal slice are juxtaposed; the latter found in the tectonic position of the Arosa zone. The presence of transform faults underlines the strong imprint of the opening of the North Atlantic Ocean on the depositional setting and tectonic evolution of the NCA.</p> </abstract>ARTICLE2022-07-28T00:00:00.000+00:00Editorial Note: Veleka Beach - the place where the mountain touches the sea model of the “Chemistry training process” system when applying semiotic approaches<abstract> <title style='display:none'>Abstract</title> <p>The present development uses the modeling method described in the literature and proposed a new didactic, functional model of the “chemistry training” system in the application of semiotic approaches: semantic, pragmatic, and syntactic. The main objective of creating such a model is to demonstrate the specific activities of the subjects “teacher” and “pupil” when familiarizing themselves with chemical symbols and their study by students. The added new components in the model “Technology of chemistry training”, “Semiotic information” and the clarified links between them, lead to a complete change in the way the described system works. The developed didactic model makes it easy to guess the relationship between a new learning situation and a result, that is, to predict an unknown process or phenomenon. This model makes it possible to formulate a reasoned hypothesis of the study.</p> </abstract>ARTICLE2022-07-28T00:00:00.000+00:00New data on the presence of the Blotched snake ( Pallas, 1814) in the region of Shumen town (Bulgaria), with emphasis on the negative human attitude toward the species<abstract> <title style='display:none'>Abstract</title> <p>In the present study, we report on new localities in Northeastern Bulgaria, where Elaphe sauromates (Pallas, 1814) was recently detected. We registered five Blotched snakes in the region of Shumen town in the period 2018 - 2022. All of the snakes were adults, three were killed by tools impacts and two of them were road kills. To date, the Blotched snake was registered extremely rare and in rather long intervals (of several decades) in the region of Shumen. Our findings indicate that the species currently inhabits the suburban and urban territories near the villages of Ivanski, Radko Dimitrievo and Konyovets. Two of the locations are new for the 10 km grid-system used for standard monitoring of the biodiversity in Bulgaria.</p> </abstract>ARTICLE2022-07-28T00:00:00.000+00:00en-us-1