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An Intergrated Model of Motion, Steering, Positioning and Stabilization of an Unmanned Autonomous Maritime Vehicle
PublicationIn the paper the aim of an interdisciplinary research is presented. The research method is introduced. An object the unmanned autonomous maritime vehicle is briefly described. The key research problem concerns a combined model of the vehicle motion including the loads of lift and hydrodynamic nature. The model takes into account the gravity and displacement forces, resistance and thrust forces, lift and other hydrodynamic forces....
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Sailing Vessel Routing Considering Safety Zone and Penalty Time for Altering Course
PublicationIn this paper we introduce new model for simulation sea vessel routing. Besides a vessel types (polar diagram) and weather forecast, travel security and the number of maneuvers are considered. Based on these data both the minimal travelling costs and the minimal processing time are found for different vessels and different routes. To test our model the applications SailingAssistance wad improved. The obtained results shows that...
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Modeling of Combined Phenomena Affecting an AUV Stealth Vehicle
PublicationIn the paper some results of research connected with modelling the basic stealth characteristics of an AUV vehicle are presented. First of all a general approach to design of the stealth AUV autonomous underwater vehicle under consideration is introduced. Then, the AUV stealth vehicle concept is briefly described. Next a method of modelling of the stealth characteristics is briefly described as well. As an example of the stealth...
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Streaming Real-time Data in Distributed Dispatcher and Teleinformation Systems for Visualization of Multimedia Data of the Border Guard
PublicationSurveillance of the sea borders is a very important task for the Border Guard. Monitoring of country maritime border is an important task of the Border Guard. This task can be facilitated with the use of the technology enabling gathering information from distributed sources and its supervision and visualization. This task can be accomplished using a technology that allows to collect information from distributed sensors of different...
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A hybrid model of flooding of the ro-ro ships in damaged conditions
PublicationThe paper presents some results on investigations concerning development of a hybrid model for assessment of performance of the ro‐ro ships in damaged conditions. The model is devoted towards assessing the performance of the damaged ro‐ro ships at the preliminary stage of design. The key problems associated with preparing of such the model are associated with working out a method of assessment of the damaged roro ships performance,...
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Trim Optimisation - Theory and Practice
PublicationForce Technology has been working intensively with trim optimisation tests for almost last 10 years. Focus has primarily been put on the possible power savings and exhaust gases reduction. This paper describes the trim optimisation process for a large cargo vessel. The physics behind changed propulsive power is described and the analyses in order to elaborate the optimum trimmed conditions are presented. Different methods for prediction...
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Use of a Least Squares with Conditional Equations Method in Positioning a Tramway Track in the Gdansk Agglomeration
PublicationSatellite measurement techniques have been used for many years in different types of human activity, including work related to staking out and making use of rail infrastructure. First and foremost, satellite techniques are applied to determine the tramway track course and to analyse the changes of its position during its operation. This paper proposes using the least squares with conditional equations method, known in geodesy (LSce)....
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Heuristic Method of Safe Manoeuvre Selection Based on Collision Threat Parameters Areas
PublicationThis paper is a continuation of papers dedicated to a radar-based CTPA (Collision Threat Parameters Area) display designed to support safe manoeuvre selection. The display visualizes all the ships in an encounter and presents situational overview from the own ship’s point of view. It calculates and displays information on unsafe or unrealistic own ship’s course & speed allowing a user to select a safe manoeuvre. So far only the...
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Modeling of performance of a AUV vehicle towards limiting the hydro-acoustic field.
PublicationSome results of research devoted to the modeling of a AUV-Stealth vehicle performance towards limiting its hydro-acoustic field are presented in the paper. At the beginning the AUV-Stealth autonomous underwater vehicle concept is described. Then the method of research is introduced. Next the key design drivers of the AUV-Stealth vehicle are presented. Between them are the AUV-Stealth hull form, arrangement of internal spaces,...
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Fractional Order Dynamic Positioning Controller
PublicationImproving the performance of Dynamic Positioning System in such applications as station keeping, position mooring and slow speed references tracking requires improving the position and heading control precision. These goals can be achieved through the improvement of the ship control system. Fractional-order calculus is a very useful tool which extends classical, integer-order calculus and is used in contemporary modeling and control...
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Algorithms for Ship Movement Prediction for Location Data Compression
PublicationDue to safety reasons, the movement of ships on the sea, especially near the coast should be tracked, recorded and stored. However, the amount of vessels which trajectories should be tracked by authorized institutions, often in real time, is usually huge. What is more, many sources of vessels position data (radars, AIS) produces thousands of records describing route of each tracked object, but lots of that records are correlated...
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A Simulative Comparison of Ship Domains and Their Polygonal Approximations
PublicationThe paper investigates the impact of a precise ship domain shape on the size of collision avoidance manoeuvres. The considered collision avoidance manoeuvres include both course and speed alterations. Various ship domains are compared with their polygonal approximations, which vary in the number of points of a domain contour and placement of these points. The best of all considered approximations is determined in the course of...
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Cloning and characterization of a novel cold-active glycoside hydrolase family 1 enzyme with beta-glucosidase, beta-fucosidase and beta-galactosidase activities.
PublicationBackground: Cold-active enzymes, sourced from cold-adapted organisms, are characterized by high catalytic efficiencies at low temperatures compared with their mesophilic counterparts, which have poor activity. This property makes them advantageous for biotechnology applications as it: (i) saves energy costs, (ii) shortens the times for processes operated at low temperatures, (iii) protects thermosensitive substrates or products...
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The influence of the geographic positioning system error on the quality of ship magnetic signature reproduction based on measurements in sea conditions
PublicationIn previous studies, the authors performed the magnetic signature reconstruction of the marine ship Zodiak as part of the measurement campaign focused on recording magnetic data and the relative position of a ship during its passage over a magnetometer immersed on the testing ground. A high degree of representation of the magnetic signature was obtained. However, the recorded measurement data revealed new patterns of the multidipole model...
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Unlocking the Secrets of River Pollution: Analyzing Organic Pollutants in Sediments—Experimental Study
PublicationUntreated wastewater released into rivers can result in water pollution, the spread of waterborne diseases, harm to ecosystems, contamination of soil and groundwater, as well as air pollution and respiratory problems for nearby humans and animals due to the release of greenhouse gases. The current study aims to investigate the recent input of anthropogenic loads into the rivers using linear alkylbenzene (LAB), which is one of the...
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Towards a modification of a regulatory framework aiming at bunker oil spill prevention from ships - A design aspect of bunker tanks vents location guided by CFD simulations
PublicationAlthough accidental bunker oil spills at seaway are relatively rare events, they can be pose real threat to the natural marine environment. One of the reasons for the bunker spill to occur is a design failure; one of the ways it can demonstrate is an improper location or height of vent heads, leading to a bunker oil discharge during heavy rolling, due to sloshing phenomenon. Design of a ship and her systems is guided by various...
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Study of various machine learning approaches for Sentinel-2 derived bathymetry
PublicationIn recent years precise and up-to-date information regarding seabed depth has become more and more important for companies and institutions that operate on coastlines. While direct, in-situ measurements are performed regularly, they are expensive, time-consuming and impractical to be performed in short time intervals. At the same time, an ever-increasing amount of satellite imaging data becomes available. With these images, it...
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Spatial distribution of pharmaceuticals in conventional wastewater treatment plant with Sludge Treatment Reed Beds technology
PublicationPharmaceutical residues are an emerging environmental problem. It is strongly confirmed that pharmaceuticals are present in soils and environmental waters (surface, marine and even groundwater), and that wastewater treatment plant (WWTP) effluents are the main source of pharmaceuticals in the watershed. The aim of this studywas to recognize the spatial distribution and seasonal changes of selected pharmaceuticals in conventional WWTP...
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Analysis of catalitic reactors usefulness to reduce pollution generated by piston combustion engines with regard to ship main engines
PublicationThe article presents results which indicate that the use of catalytic reactors to reduce emissions of harmful compunds contained in the exhaust gas is important in the operation of vehicle motors operation. Efforts of the shipbuilding industry to reduce the toxicity of exhaust gas emitted by the main engines have been indicated and pointed to the desirability of the use of these catalysts in maritime transport. It has been pointed...
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Exposure of a small Arctic seabird, the little auk (Alle alle) breeding in Svalbard, to selected elements throughout the course of a year
PublicationThe Arctic marine ecosystem can be altered by processes of natural and anthropogenic origin. Spatio-temporal variation in species exposure to contamination is still poorly understood. Here, we studied elemental concentrations in the non-lethally collected samples from the most numerous seabird in European Arctic, the little auk (Alle alle) nesting in one breeding colony in Svalbard. This seabird spent the breeding season in the...
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Effects of biotransport and hydro-meteorological conditions on transport of trace elements in the Scott River (Bellsund, Spitsbergen)
PublicationThe shaping of surface water chemistry in the Svalbard Archipelago is strongly dependent on the geology of the catchment and the process of long-range transport of atmospheric pollutants (LRATP). It was found that the dissolved trace elements in the Scott River, which catchment is characterized by a decreasing degree of glaciation, were of the natural origin (i.a. weathering and dissolution of local geological substratum). The...
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Synteza układu sterowania statkiem morskim dynamicznie pozycjonowanym w warunkach niepewności
PublicationNiniejsza monografia obejmuje zagadnienia związane z syntezą układu dynamicznego pozycjonowania statku w środowisku morskim z zastosowaniem wybranych nieliniowych metod sterowania. W ramach pracy autorka rozważała struktury sterowania z zastosowaniem wektorowej adaptacyjnej metody backstep oraz metod jej pokrewnych, takich jak regulatory MSS (ang. multiple surface sliding), DSC (ang. dynamic surface control), NB (ang. neural backstepping)....
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Medium-Voltage Drives: Challenges and existing technology
PublicationThe article presents an overview of state-of-art solutions, advances, and design and research trends in medium-voltage (MV) drive technologies - and also discusses the challenges and requirements associated with the use of such drives. The choice and deployment of MV drives in industries are associated with numerous requirements related to the front-end converter (grid side) and inverter (machine side). The focus is on solutions...
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Seasonal changes of mercury speciation in the coastal sediments
PublicationPurpose Mercury speciation in sediments is linked to environmental conditions and processes. Domination of particular mercury species depends on its source, displays considerable seasonal behavior, and may be further modified due to oxygen levels, icing conditions, or the input of fresh organic matter. The purpose of this study was to examine the coastal area of the Gulf of Gdańsk in terms of mercury contamination and the influence...
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Identification of damages in the inlet air duct of a diesel engine based on exhaust gas temperature measurements
PublicationThe temperature of the exhaust gas of a diesel piston engine, measured in the characteristic control sections of its thermo-flow system, can be a valuable source of diagnostic information about the technical condition of the elements limiting the working spaces thus separated, including the turbocharging system, but also its fuel supply system and replacement of the medium. In standard marine engine measurement systems equipped...
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Converting beach wrack into a resource as a challenge for the Baltic Sea (an overview)
PublicationThe paper distinguishes beach wrack, the marine generated organic part of beach cast, as a separate management object and discusses research questions related to its management and economically viable use. Based on experiences from the Baltic Sea and existing practices from countries with different management systems clear distinction between the management of natural and anthropogenic components of cast material is seen as an...
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Plastic Debris in the Stomach of the Invasive Signal Crayfish Pacifastacus leniusculus from a Baltic Coastal River
PublicationPollution by plastic debris, widely recognized as a growing global problem [1-3] is caused by the production of synthetic polymers. Over recent years, the production of plastics has increased, while in Europe, fossil-based plastics production has decreased, and recycled plastics production has increased [4]. There are different types of plastics. Some types of plastic ingredients, applied in a wide variety of cosmetics and personal...
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Distribution and bioavailability of mercury in the surface sediments of the Baltic Sea
PublicationThe study aimed to determine the level of mercury (Hg) and its labile and stable forms in the surface sediments of the Baltic Sea. The work considers the impact of current and historical sources of Hg on sediment pollution, together with the influence of different environmental parameters, including water inflows from the North Sea. Surface sediments (top 5 cm) were collected in 2016–2017 at 91 stations located in different...
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A geophysical, geochemical and microbiological study of a newly discovered pockmark with active gas seepage and submarine groundwater discharge (MET1-BH, central Gulf of Gdańsk, southern Baltic Sea)
PublicationHigh-resolution bathymetric data were collected with a multi-beam echosounder in the southern part of the Baltic Sea (region MET1, Gulf of Gdańsk) revealing the presence of a 10 m deep and 50 m in diameter pockmark (MET1-BH) on the sea bottom (78.7 m). To date, no such structures have been observed to reach this size in the Baltic Sea. The salinity of the near-bottom water in the pockmark was about 2 PSU (about 31.22 mmol/l...
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Mercury concentrations in Antarctic zooplankton with a focus on the krill species, Euphausia superba
PublicationThe Antarctic is the most isolated region in the world; nevertheless, it has not avoided the negative impact of human activity, including the inflow of toxic mercury (Hg). Hg deposited in the Antarctic marine environment can be bioavailable and accumulate in the food web, reaching elevated concentrations in high-trophic-level biota, especially if methylated. Zooplankton, together with
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Safety of Bariatric Surgery in ≥ 65-Year-Old Patients During the COVID-19 Pandemic
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30-Day Morbidity and Mortality of Bariatric Surgery During the COVID-19 Pandemic: a Multinational Cohort Study of 7704 Patients from 42 Countries
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Effect of BMI on safety of bariatric surgery during the COVID-19 pandemic, procedure choice, and safety protocols – An analysis from the GENEVA Study
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30-day morbidity and mortality of sleeve gastrectomy, Roux-en-Y gastric bypass and one anastomosis gastric bypass: a propensity score-matched analysis of the GENEVA data
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