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Search results for: HYDRAULIC ACTUATOR POSITION
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Heat transfer intensification by enlarged surface roughness in the plate heat exchanger
PublicationIn the paper an experimental analysis of passive heat transfer intensification technique employed in the case of the plate heat exchanger is presented. The passive intensification was obtained by a modification of the heat transfer surface. The roughness of surface was increased by a use of glass micro-beads. Single-phase convective heat transfer in the water-water system was studied. The experiment was accomplished in two stages....
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Studies on the influence of technological variants of finishing machining on flow of parts in flexible manufacturing
PublicationIn the article below the problems of influence of variants of finishing processing on flow of machining parts in flexible manufacturing system were presented. The investigations were carried out the technological processes for piston rods and rams of hydraulic cylinders. There were also presented model variants of technological processes for piston rods finished with the burnishing. In these studies the influence of technological...
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Freeze-Up Ice Jam Formation in the River Bend, a Case Study on the Inner Mongolia Reach of Yellow River
PublicationConcern has been expressed regarding the impacts of climate change on river ice and ice jam formation in cold regions. Ice jams are easily initiated in bends and narrow channels and cause disasters. In this study, observations and remote sensing monitoring are used to study the freeze-up ice jam formation of bends. Sediment transport and freezing process of the river interact, influencing bed changes profile and sedimentary budget....
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Recent advances on the removal of phosphorus in aquatic plant-based systems
PublicationPhosphorus (P) is a vital nutrient for the ecosystems and its excess in wastewater streams leads to some environmental issues such as extensive algae growth (eutrophication). Phytoremediation is a green technology that is based on the combined actions of plants and their associated microbial groups to remove and transfer the toxic compounds in surface water, groundwater and soil. Aquatic plants are widely used for the remediation...
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Liquefaction of alder wood as the source of renewable and sustainable polyols for preparation of polyurethane resins
PublicationLiquefaction of wood-based biomass gives different polyol properties depending on the reagents used. In this article, alder wood sawdust was liquefied with glycerol and poly(ethylene glycol) solvents. Liquefaction reactions were carried out at temperatures of 120, 150 and 170 °C. The obtained bio-polyols were analyzed in order to establish the process efficiency, hydroxyl number, acid value, viscosity and structural characteristics...
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Pathways of Nitrogen Removal in Hybrid Treatment Wetlands
PublicationHybrid Treatment Wetlands (HTWs) are composed of two or more filters with different modes of flow, allowing the benefits of both types of bed to be combined, resulting in better effluent quality (nitrogen and organic compounds removal). Such a heterogeneous environment creates possibilities for different mechanisms of nitrogen removal. The objective of the present study was to investigate the removal of nitrogen versus a range...
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Minimization of a ship's magnetic signature under external field conditions using a multi-dipole model
PublicationThe paper addresses the innovative issue of minimizing the ship's magnetic signature under any external field conditions, i.e., for arbitrary values of ambient field modulus and magnetic inclination. Varying values of the external field, depending on the current geographical location, affect only the induced part of ship's magnetization. A practical problem in minimizing the ship signature is separating permanent magnetization...
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Problemy ukrytych aportów w spółkach publicznych
PublicationTransakcje z samym sobą należą do typowych zachowań dominującego akcjonariusza nadużywającego swojej pozycji w spółce publicznej. W artykule omówiono ukryte aporty, które są efektem tego typu zachowań. Wskazano, czym różnią się ukryte aporty od prawidłowo wnoszonych aportów i jakie są negatywne konsekwencje tych pierwszych. W rozważaniach uwzględniono aspekty prawne tego zjawiska. Opisane zostały przypadki obchodzenia przepisów...
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Rozprzestrzenianie się w podtorzu skutków katastrof kolejowych z udziałem materiałów niebezpiecznych
PublicationDuża część przewozów materiałów niebezpiecznych prowadzona jest koleją. W związku z tym bezpieczeństwo tych przewozów nabiera coraz większego znaczenia. Każda katastrofa z udziałem materiałów niebezpiecznych ma negatywny wpływ na uczestników tego zdarzenia oraz na otaczające środowisko, bowiem jej zasięg na ogół nie jest lokalny. Z tego wynika, że w przypadku zaistnienia katastrofy należy minimalizować jej skutki oraz w dalszych...
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Dynamics of cutting power during sawing with circular saw blades as an effect of wood properties changes in the cross section
PublicationIn the paper the effect of the method calculation upon the cutting power is presented. In computations were used models in which fracture toughness was incorporated. The comparison concerned models as follows: FM-CM – classic model in which the sum of all uncut chip thicknesses of the simultaneously teeth engaged represented the mean uncut chip thickness, FM-FDM – full dynamical model in which besides variable uncut chip thickness...
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Wear estimation of current collector contact strips by analysis of a 3D scanning results
PublicationThe technical condition of current collector contact strips is very important when operational reliability of railway transportation is considered. The authors proposed a novel measurement system based on a 3D camera to register the shape and dimensions of the current collector contact strips surface. The system was installed above the railway track for tests in target ambient. During the trial operation a few dozen of contact...
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Numerical Analysis of Impact of Energy Buoy Anchoring Configurations on its Motion and Efficiency
PublicationThis paper presents a numerical analysis of the impact of energy buoy mooring configurations on its movement on the wave and effectiveness. The method used to analyse the buoy movement modelling in six degrees of freedom was described in a paper presented at the Conference 2011. Simulations of the buoy movement in regular wave and power calculations were conducted for several configurations of anchoring systems and position of...
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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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Frequency-dependent coupling model for microwave band-pass filter
PublicationThe goal of this work was to create a circuit model which represents frequency-dependent coupling between microwave resonators. Our models are designed for in-line filters. The frequency-dependent coupling enables one to realize a transmission zero which is not possible in classical approach with frequency independent inverters. In addition, the proposed model allows us to observe out-of-band behavior, e.g. spurious resonance....
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Resolving conflicts in object tracking for automatic detection of events in video
PublicationW referacie przedstawiono algorytm rozwiązywania konfliktów w śledzeniu obiektów ruchomych. Proponowana metoda wykorzystuje predykcję stanu obiektu obliczaną przez filtry Kalmana oraz dopasowuje wykryte obiekty do struktur śledzących ich ruch na podstawie deskryptorów koloru i tekstury. Omówiono specyficzne sytuacje powodujące konflikty, takie jak rozdzielanie obiektów. Przedstawiono wyniki testów. Algorytm może być zastosowany...
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Human-Computer Interface Based on Visual Lip Movement and Gesture Recognition
PublicationThe multimodal human-computer interface (HCI) called LipMouse is presented, allowing a user to work on a computer using movements and gestures made with his/her mouth only. Algorithms for lip movement tracking and lip gesture recognition are presented in details. User face images are captured with a standard webcam. Face detection is based on a cascade of boosted classifiers using Haar-like features. A mouth region is located in...
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Hydrothermal Cobalt Doping of Titanium Dioxide Nanotubes towards Photoanode Activity Enhancement
PublicationDoping and modification of TiO2 nanotubes were carried out using the hydrothermal method. The introduction of small amounts of cobalt (0.1 at %) into the structure of anatase caused an increase in the absorption of light in the visible spectrum, changes in the position of the flat band potential, a decrease in the threshold potential of water oxidation in the dark, and a significant increase in the anode photocurrent. The material...
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3D Monitoring - Identification of measurement problems at larger movements of the tracked points
PublicationAuthors identified the problems associated with the determination of the controlled points coordinates by use of automated Total Station placed behind transparent barrier. Important thing in the mentioned analysis was a large change of controlled points position and not stable Total Station’s stand (because of stand’s thermal drift). This two elements, combined with measurement made through glass plate determine the need for impact...
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Within- and between-firm wage inequalities and trade integration in GVC
PublicationThis paper examines between- (inter) and within- (intra) firm wage inequality using rich employer-employee data for 12 European countries. We confirm that much overall wage inequality is observed within sectors and within occupations. The share of the within- and between-firm components in overall wage inequality varies across countries. We estimate the link between involvement in global value chains (GVCs) and wages differentiating...
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The Importance of Demand and Environment for Defining and Establishing the Role of Data Stewards
PublicationData stewardship is now a central part of FAIR research data management. Although various types of positions called data stewards have been created at academic institutions over the last years, no demand-oriented, formal model of data stewardship and the associated roles exist so far. This workshop report presents the outcomes of the panel discussion “The Importance of Demand and Environment for Defining Data Stewardship” held...
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Diamond investments – Is the market free from multiple price bubbles?
PublicationThe following study aims to investigate whether multiple price bubbles, in which the quoted market price of diamonds significantly deviates from their fundamental value, exist in the diamond market. It was conducted using ADF, SADF and GSADF tests, with the latter found to be an optimal form of evaluating the analysed issue. The presented results support the conclusion that the diamond market is not free from periods defined as...
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Topochemical, Single‐Crystal‐to‐Single‐Crystal [2+2] Photocycloadditions Driven by Chalcogen‐Bonding Interactions
PublicationThe face-to-face association of (E)-1,2-di(4-pyridyl)ethylene (bpen) molecules into rectangular motifs stabilized for the first time by chalcogen bonding (ChB) interactions is shown to provide photoreactive systems leading to cyclobutane formation through single-crystal-to-single-crystal [2+2] photodimerizations. The chelating chalcogen bond donors are based on original aromatic, ortho-substituted bis(selenocyanato)benzene derivatives...
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Analysis of a caustic formed by a spherical reflector: Impact of a caustic on architectural acoustics
PublicationFocusing sound in rooms intended for listening to music or speech is an acoustic defect. Design recommendations provide remedial steps to effectively prevent this. However, there is a category of objects of high historical or architectural value in which the sound focus correction is limited or even abandoned. This also applies to indoor or outdoor concert shells, installations for teaching and acoustic presentations, etc. The...
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The potential of web awareness as a determinant of dually defined customer value
PublicationIn the conditions of increasing demand barrier, the enterprise’s basic capital is customers. From an enterprise point of view, this means the need to create a dual perceived and defined customer value which remains related to market value (income and development potential) and customer resource value (reference, information and cooperative potential). The progressing digitisation process transfers business processes, and thus relationships, into...
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Information transfer during the universal gravitational decoherence
PublicationRecently Pikovski et al. (Nat Phys 11:668, 2015) have proposed in an intriguing universal decoherence mechanism, suggesting that gravitation may play a conceptually important role in the quantum-to-classical transition, albeit vanishingly small in everyday situations. Here we analyze information transfer induced by this mechanism. We show that generically on short time-scales, gravitational decoherence leads to a redundant information...
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Modeling the impact of rotor movement on non-linearity of motor currents waveforms in high-speed PMSM drives
PublicationMotor current measurement techniques as well as predictive control algorithms for electric drives rely on an assumption of linear motor currents changes resulting from constant inverter output voltages. Recent research has reported that this assumption does not hold in motors with short electrical time constant, and in drives whose rotor position advances substantially during a control period. This paper proposes a simulation model...
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The analysis of the determination of points positions using photogrammetric methods
PublicationThis article was created as a result of research conducted within the master thesis. The purpose of the research was to analyze the accuracy of determining the actual position of the photographed points according to the calculated parameters. The accuracy of photos alignment was determined as parameters, which determine their external and internal orientation. In order to determine the location of the determined points, it was...
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Effect of manufacturing errors of the pad sliding surface on the performance of the hydrodynamic thrust bearing
PublicationIn the present study, investigation of the effect of manufacturing errors on the performance of large tilting pad thrust bearings has been performed, following a CFD-based Thermohydrodynamic analysis of a single pad. A 3D model has been generated, including the pad, the lubricant film and the corresponding part of the collar. The pad has been assumed to be deformed about the pivot point, due to thrust loading. Manufacturing errors...
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Collection Efficiency in Narrow Electrostatic Precipitators with a Longitudinal or Transverse Wire Electrode
PublicationRecently narrow electrostatic precipitators (ESPs) have become a subject of interest because of their possible application in diesel engine exhaust systems. In this work, results of particle collection efficiency measurements in narrow electrostatic precipitators for negative and positive dc voltage polarity are presented. The ESP usedin this work was a parallelepiped equipped with wire discharge electrode and two collecting plate-electrodes....
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Framework for extracting rails and setting-out railway line axis based on UAV photogrammetric measurements
PublicationTechnical diagnostics enables assessing the current technical condition of a railway line and adjacent infrastructure, and forecasting its changes over a specific time horizon. One of its elements is the periodic monitoring of rail position and their geometry. This article presents a new framework for the setting-out of a railway track axis. The process presented in the manuscript is based on the specific filtration and extraction...
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Weather Routing System Architecture Using Onboard Data Collection and Route Optimisation
PublicationThis 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...
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The influence of polymer bearing material and lubricating grooves layout on wear of journal bearings lubricated with contaminated water
PublicationThe goal of the present paper is to investigate wear properties of journal sliding bearing operating in the conditions of contaminated water lubrication. Several bearing materials and bearing sleeve designs (differing in the axial grooves position and their shape) were tested experimentally under typical operating conditions in a dedicated test rig, which was equipped with a lubricating system, enabling lubrication with contaminated...
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Analysis of the Hydrodynamic Properties of the 3-Column Spar Platform for Offshore Wind Turbines
PublicationThe 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...
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The effects of different aeration modes on ammonia removal from sludge digester liquors in the nitritation–anammox proces
PublicationThe aim of this study was to determine the impact of continuous and intermittent aeration on the rate of ammonia removal in the combined nitritation–anammox process. This process was run in two parallel sequencing batch reactors (SBRs), with a working volume V = 10 L, treating sludge digester liquors from the Gdansk (Poland) wastewater treatment plant (WWTP). The ammonia oxidizing bacteria were cultivated from activated sludge...
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POLDER AND CITY: SUSTAINING WATER LANDSCAPES ON AN URBAN EDGE
PublicationThe question investigated in this paper is how to maintain the environmental quality of the polder landscape encompassing the city in the condition of urban pressure on this landscape. On the basis of theoretical approaches, historical surveys and introductory study models new ideas are tested on the case study of Gdansk, a city located in the Vistula River delta in northern Poland. Research shows that the city was created as a...
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PRELIMINARY RESULTS FROM APPLICATION PHOSLOCK® TO REMOVE PHOSPHORUS COMPOUNDS FROM WASTEWATER
PublicationThe aim of the study is to assess the removal effectiveness of phosphorus compoundsby using lanthanum-modified bentonite. This material was produced by the Australian company Phoslock® Water Solutions Pty Ltd. According to the company, Phoslock® has substantial capacity to bound phosphate anions. The investigation was carried out in steady conditions in laboratory model with beakers. The results of the study are related to the...
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Climate change impact on groundwater resources in sandbar aquifers in southern Baltic coast
PublicationShallow coastal aquifers are vulnerable hydrosystems controlled by many factors, related to climate, seawater‑freshwater interactions and human activity. Given on‑going climate change, sea level rise and increasing human impact, it is especially true for groundwater resources situated in sandbars. We developed numerical models of unsaturated zone water flow for two sandbars in northern Poland: the Vistula Spit and the Hel Spit...
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Zintegrowane sterowanie systemami zaopatrzenia w wodę pitną
PublicationOptymalne ekonomicznie zaspokojenie w miastach bieżącego zapotrzebowania na wodę pitną tak, aby spełnione były wymagania jakości dostaw oraz jakości samej wody jest złożonym zadaniem. Zarówno aspekty aplikacyjne jak i teoretyczne tego problemu są przedmiotem intensywnych prac prowadzanych w sektorach naukowych i przemysłowych na całym świecie. Prace te finansowane są przez przemysł, komitety naukowe oraz Programy Ramowe Unii Europejskiej....
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Porównanie mocy strat energetycznych w pompie wyporowej o zmiennej wydajności określonych bez uwzględnienia bądź z uwzględnieniem mocy ściskania oleju hydraulicznego
PublicationPorównano moce strat energetycznych w pompie wyporowej o zmiennej wydajności, określone bez uwzględnienia bądź z uwzględnieniem mocy ściskania oleju hydraulicznego. Ocena mocy ściskania cieczy w pompie stała się możliwa dzięki zastosowaniu, zaproponowanej przez autora, metody określenia stopnia zapowietrzenia cieczy w pompie. W metodzie określenia stopnia zapowietrzenia cieczy w pompie oraz w ocenie mocy strat objętościowych ściskania...
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Ocena stanu technicznego konstrukcji pras filtracyjnych w Grupowej Oczyszczalni Ścieków „DĘBOGÓRZE” w Gdyni
PublicationPodstawowym celem pracy była rzeczowa ocena z punktu widzenia technicznego stanu trzech pras filtracyjnych, usytuowanych w budynku, położonym w Oczyszczalni Ścieków ‘DEBOGÓRZE w Gdyni. Zakres prac obejmował szczegółowa ocenę trzech układów w każdej prasie a mianowicie: - hydraulicznego, - sterowania i automatyki, - mechanicznego – związanego ze sprawdzeniem stanu konstrukcji nośnej i obudów.. Opis i analiza stanu poszczególnych...
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Testing of Software for the Planning of a Linear Object GNSS Measurement Campaign under Simulated Conditions
PublicationThe precision of a linear object measurement using satellite techniques is determined by the number and the relative position of the visible satellites by the receiver. The status of the visible constellation is described by DOP. The obtained geometric coefficient values are dependent on many variables. When determining these values, field obstacles at the receiver location and satellite positions changing with time must be taken...
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TDOA versus ATDOA for wide area multilateration system
PublicationThis paper outlines a new method of a location service (LCS) in the asynchronous wireless networks (AWNs) where the nodes (base stations) operate asynchronously in relation to one another. This method, called asynchronous time difference of arrival (ATDOA), enables the calculation of the position of the mobile object (MO) through the measurements taken by a set of non-synchronized fixed nodes and is based on the measurement of...
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Możliwości redukcji przebiegowego zużycia paliwa przy zastosowaniu elektronicznych systemów wspomagających kierowców
PublicationElektroniczne systemy wspomagające kierowcę pomagają kierującym kontrolować sytuację na drodze, przekazują sygnały do układu hamulcowego i napędowego, rozpoznają znaki drogowe, pozwalają utrzymać odpowiedni dystans w czasie jazdy w kolumnie, a także kontrolują położenie pojazdu na pasie ruchu. Elek-troniczne systemy wspomagające kierowcę pomagają również zmniejszyć przebiegowe zużycie paliwa, poprzez odpowiednie sterowanie układem...
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Wykorzystanie słabych sygnałów, foresightu i ciągu zarządzania strategicznego w konfiguracji biznesu przyszłości
PublicationBurzliwość współczesnego otoczenia wyostrza zagadnienie przystosowania prowadzonej działalności gospodarczej do funkcjonowania w przyszłości. Do osiągnięcia sukcesu w biznesie przyszłości przyczynić się może wykorzystanie dostępnej już obecnie wiedzy. Na szczególną uwagę zasługuje teoria słabych sygnałów, metoda foresight oraz ciąg zarządzania strategicznego, które w połączeniu umożliwiają wypracowanie stanowiska w sprawie kształtu...
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Design and distribution of air nozzles in the biomass boiler assembly
PublicationDue to energy crisis as well as increasing pollution of the environment, renewable energy sources usage increases all over the world. These facts encouraged authors to start research over developing a uniform biomass boiler calculation model. This paper presents a design of biomass boiler assembly created for ORC (Organic Rankine Cycle) unit since these systems could achieve strong position in energy industry....
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In-service measurement of the small wind turbine test stand for structural health monitoring
PublicationThis paper presents the research activity performed on a Small Wind Turbine (SWT) test stand. Commercially available turbine was modified towards incorporation of the sensors system for condition monitoring. Installed sensors measure angular shaft position, torque applied from the wind loads, vibration accelerations and last but not least rotational speed. All gathered data are then transferred and processed in Test.Lab by means...
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On Some Aspects of Fish Target Strength Estimation in Shallow Waters
PublicationThe theory of acoustic surveys for determining fish abundance are well established in fishery acoustics. The origins of the estimation are related to overcoming the problem of unknown position of target in the beam using statistical inversion. Although recently researchers use more sophisticated echosounders that provides more informative data allowing for direct solution it is known that the results are biased due to not ideally...
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Experimental Study of Silent Sonar
PublicationStealth is a frequent requirement in military applications and involves the use of devices whose signals are difficult to intercept or identify by the enemy. The silent sonar concept was studied and developed at the Department of Marine Electronic Systems of the Gdansk University of Technology. The work included a detailed theoretical analysis, computer simulations and some experimental research. The results of the theoretical...
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Structural and optical investigations of sol-gel derived lithium titanate thin films
Publicationin this paper structural and optical studies of lithium titanate (lto) thin films are presented. nanocrystalline thin films with 800 nm thickness were prepared by sol-gel method. to examine the influence of the annealing time on as-prepared films crystallization, the coatings were heated at 550 °c for 10, 20 and 80 h. structure of manufactured thin films was investigated using x-ray diffraction (xrd). the most visible lithium titanate...
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Convenient synthesis of 3-phosphono-β-lactams through the cyclization ofN-alkenyl-phosphonoacetamides
PublicationOxidative cyclization through the treatment by the transition metals is convenientsynthetic tool with a great number of applications. In the most cases the result is the formationof C-C bond between generated radical and unsaturated part of the same or another molecule.As it was presented by Trogolo it is also suitable way to obtain 4-membered heterocyclicβ-lactamic ring[1]. In this communicate we want to present new application...