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Changes in the number of commercial banks in 1992-2004
Dane BadawczeAs the data shows, it can be concluded that the number of banks in Poland is small. The main reason for the declining number of banks is bank acquisitions by foreign investors or bank consolidation. To a lesser extent, this change resulted from negative factors such as bankruptcy or liquidation.
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Bowaryzm jako samotność. „Miłość” Hanne Ørstavik, czyli opowieść o norweskiej pani Bovary końca XX wieku
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[ITiT] Transmission Channel in Radio Communication Systems - 2023/2024
Kursy Online{mlang pl} Dyscyplina: informatyka techniczna i telekomunikacja Zajęcia fakultatywne dla doktorantów II roku Prowadzący: dr hab. inż. Sławomir Ambroziak, prof. PG Liczba godzin: 15 Forma zajęć: wykład {mlang} {mlang en} Discipline: technical informatics and telecommunications Elective course for 2nd-year PhD students Academic teachers: dr hab. inż. Sławomir Ambroziak, prof. PG Total hours of training: 15 teaching hours Course...
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Source and Channel Coding in Radio Communication Systems 2023/2024
Kursy OnlineKurs służy jako narzędzie pomocnicze do realizacji przedmiotu.
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Heat exchange enhancement of jet impingement cooling with the novel humped-cone heat sink
PublikacjaJet impingement cooling technology is applicable to control temperature of devices, where very high heat flux is generated within a small area. This paper is about the improvement of the jet impingement cooling efficiency by the heat sink geometry modification. Two reference cases were sourced from the literature – flat heat sink and modified one with cone in the jet stagnation region. Such a change improves cooling capability...
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Electrochemical Synthesis of Photocatalyst
PublikacjaPonowne wykorzystywanie i recykling fotokatalizatora nanocząsteczkowego jest nie wystarczająco rozwiązanym problem. Powszechnie fotokatalizatory są unieruchomiane przez zol-żel lub zanurzeniowo-powłokowe procedury. Jednak istnieją udokumentowane przypadki wyczerpania fotokatalizatora lub zmniejszenia jego działalności fotokatalitycznej. Synteza elektrochemiczna fotokatalizatora z natychmiastowym unieruchomieniem nie jest własciwie...
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Fluid Mechanics, L/L/E, DaPE, sem. 04, summer 21/22 (PG_00050282)
Kursy OnlineLECTURES Introduction and basic definitions. Properties of fluids. Models of fluids. Fluids in equilibrium. Determination of hydrostatic forces. Archimedes" law. Methods of fluid flow description. General motion of fluid. Deformation of fluid element. Vortex motion of fluid. Principles of conservation of mass, momentum and energy. Balance of entropy. Navier-Stokes equation. Bernoulli equation. Similarity of flow phenomena. Potential...
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Antitumor imidazoacridinone derivative C-1311 induces cell cycle arrest and cellular senescence-like phenotypic changes in human non-small lung A549 cancer cells
PublikacjaPrzeprowadzone badania miały na celu zbadanie rodzaju odpowiedzi komórkowej indukowanej przez pochodną C1311 w komórkach ludzkiego, niedrobnokomórkowego raka płuc A549, wyselekcjonowanych do badań ze względu na wysoką wrażliwość na działanie pochodnej C-1311. Wszystkie eksperymenty przeprowadzone zostały przy stężeniu hamującym proliferację komórek nowotworowych w 80%. Badania z wykorzystaniem techniki cytometrii przepływowej oraz...
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3D modelling of beach topography changes caused by the tombolo phenomenon using terrestrial laser scanning (TLS) and unmanned aerial vehicle (UAV) photogrammetry on the example of the city of Sopot
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Controlled Random Search Applied to Parameters Estimation of the Longitudinal Solutes Transport Model for Rivers
PublikacjaNumerical computations are presented for the longitudinal transport of passive, conservative solutes in an actual river with the inclusion of geometrical complexities of river channels. A special emphasis is put on the method of the identification of model parameters which is based on a specially designed optimisation procedure using random control search algorithm. Two different situations are considered namely a linear version...
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Simulation of Direct-Sequence Spread Spectrum Data Transmission System for Reliable Underwater Acoustic Communications
PublikacjaUnderwater acoustic communication (UAC) system designers tend to transmit as much information as possible, per unit of time, at as low as possible error rate. It is a particularly difficult task in a shallow underwater channel in which the signal suffers from strong time dispersion due to multipath propagation and refraction phenomena. The direct-sequence spread spectrum technique (DSSS) applied successfully in the latest standards...
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Leveraging food waste for electricity: A low-carbon approach in energy sector for mitigating climate change and achieving net zero emission in Hong Kong (China)
PublikacjaIn recent years, food waste has been a global concern that contributes to climate change. To deal with the rising impacts of climate change, in Hong Kong, food waste is converted into electricity in the framework of low-carbon approach. This work provides an overview of the conversion of food waste into electricity to achieve carbon neutrality. The production of methane and electricity from waste-to-energy (WTE) conversion are...
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Impact of maintenance of floodplains of the Vistula River on high water levels on the section from Włocławek to Toruń
PublikacjaThis article describes the methodology of hydraulic calculations to estimate the water levels in open channels for steady gradually varied flow. The presented method has been used to analyse the water level on the Vistula River from Włocławek cross-section to Toruń cross-section. The HEC-RAS modelling system has been used for parameterization of the river channel and floodplains, as well as for flow simulation. The results obtained...
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Improving listeners' experience for movie playback through enhancing dialogue clarity in soundtracks
PublikacjaThis paper presents a method for improving users' quality of experience through processing of movie soundtracks. The dialogue clarity enhancement algorithms were introduced for detecting dialogue in movie soundtrack mixes and then for amplifying the dialogue components. The front channel signals (left, right, center) are analyzed in the frequency domain. The selected partials in the center channel signal, which yield high disparity...
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Method for the correlation coefficient estimation of the bottom echo signal in the shallow water application using interferometric echo sounder
PublikacjaThe article presents a new method for the assessment of bottom echo correlation coefficient in the presence of multiple echoes. Bottom correlation coefficient is a parameter that characterizes spatial properties of echo signal. Large variability of the bottom shape or properties (for example caused by the presence of bottom objects) and the presence of the acoustic shadow strongly influence the value of the correlation coefficient....
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Andreas Haenel dr inż.
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Resistance of human prostate carcinoma cells to a new antitumor compound capridine beta is associated with changed drug metabolism combined with both inherent and drug-induced overexpression of ABC transporters
PublikacjaW pracy charakteryzujemy mechanizm oporności na nową pochodną 1-nitroakrydyny, związku capridine beta (C-1748) o wysokiej aktywności przeciwnowotworowej, znajdującego się w badaniach klinicznych. Nasze dane wskazują, że oporność na ten związek jest wynikiem zmienionego metabolizmu inaktywującego C-1748 oraz wzrostem ekspresji pompy błonowej ABCG2 a także innych białek transportowych typu ABC.
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Multibaem Sonar Records Data Decimation Using Hierarchical Spline Interpolation
PublikacjaMultibeam sonar records feature high vertical and horizontal resolution. Interpolating and approximating, eventually displaying of of high volume scattered 3D raster data leads to some difficulties related to a computer processing power. The paper presents some advantages of using hierarchical splines in the context. Such an approach facilitates real time 3D MBS data rendering.
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GeoSPAR Project. Validation and selection methods of geoinformation analysis using GIS for ranking and forecasting of terrorist threats and criminal events
PublikacjaThe paper presents the description of work activities which have already been done within the first two stages – WorkPackage 1 and WorkPackage 2 - of the GeoSPAR Project. In such a context the general conceptual design of the GIS system and associate web service was presented and analysed. In addition, the operational and technical requirements for the GeoSPAR system have been specified and discussed; with special emphasis on system...
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Methods of navigation in the mobile application supporting movement of the blind
PublikacjaThis paper presents conclusions from the last development phase of the “Voice Maps” project. Authors specify newly found available options for navigation in affordable system for the blind with all their related aspects. System uses dedicated geographical data, built-in smartphone GPS receivers and DGPS external device in order to assist blind users in their everyday travelling. Authors also discuss new methods to improve positioning...
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EGNOS-based GNSS receiver for precise positioning in restricted areas
PublikacjaPositioning accuracy is very important in many areas, whereas the typical GPS receiver accuracy is often not sufficient. The European Geostationary Navigation Overlay Service (EGNOS), Europe’s first venture into satellite navigation, improves the open public service offered by the Global Positioning System (GPS). As a satellite navigation augmentation system, EGNOS improves the accuracy of GPS by providing a positioning accuracy...
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The development of an underwater telephone for digital communication purposes
PublikacjaThe underwater telephone HTL-10 has been designed to provide voice and data communication between helicopter and submarines using acoustic waves. It works in a half-duplex mode and uses analogue power-efficient modulation in the form of a single side-band, suppressed carrier, in a wide range of frequencies. It generates the transmitted signal, and processes the received signals. It is implemented with the use of digital signal...
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Mobile inventory system for hydrotechnical objects using data from multiple sensors operating simultaneously
PublikacjaThe knowledge of the location, shape and other characteristics of spatial objects in the coastal areas has a significant impact on the functioning of ports, shipyards, and other water-infrastructure facilities, both offshore and inland. Therefore, measurements are taken of the underwater part of the waterside zone, which means the bottom of water and other underwater objects (e.g. breakwaters, docks, etc.), and objects above the...
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EGNOS-based receiver for precise positionint in restricted areas
PublikacjaPositioning accuracy is very important in many areas. EGNOS improves accuracy, but
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Potential of Polish R&D industry in the context of prototyping, design, development and control of a dedicated national satellite SAR system for marine ecosystem monitoring. Technical paper - preliminary study
Publikacjapace technology is currently one of the most important elements in the advance of information societies and knowledge-based economies all over the world. The European Space Agency (ESA) is in the focal point of European space activities, while the European Union provides strong financial support for the development of space technologies and applications in its flagship programs. In a domestic scope, the Polish Space Agency (POLSA)...
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Comparison of direct and inverse methods of satellite observations downscaling for the coastal zone area
PublikacjaThe Earth observation satellite imaging systems have known limitations, especially regarding their spatial and temporal resolution. Therefore, approaches which aim to combine data retrieved from sensors of higher temporal and lower spatial resolution with the data characterized by lower temporal but higher spatial resolution are of high interest. This allows for joint utilization of the advantages of both these types of sensors....
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Investigation of the vertical distribution of the sound speed of the Gulf of Gdansk in the years 2000-2010
PublikacjaThe conditions of the acoustic wave propagation in the southern Baltic are much more complex than in other shallow waters. In the typical shallow water, seasonal changes in acoustical conditions in the upper layer, of the depth of about 60-70 m, are observed. They are caused by variation of the annual meteorological conditions. Most often, in the deep water layer, acoustical conditions are stable throughout the year. However, in...
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SOLAP GIS in maritime research
PublikacjaMultidimensional Geographical Information System is a system especially designed to acquire, distribute, analyze and visualize complicated spatio-temporal data. Modern Geographical Information System technology can provide easy-to-use, near real-time solutions to many problems from different areas of research. In the article, authors summarize recent works on Spatial Online Analytical Processing (SOLAP) and multidimensional Geographical...
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Calibration of precipitation estimation algorithm with particular emphasis on the Pomeranian region using high performance computing
PublikacjaFast and accurate precipitation estimation is an important element of remote atmosphere monitoring, as it allows, for example, to correct short-term weather forecasts and the prediction of several types of meteorological threats. The paper presents methodology for calibrating precipitation estimation algorithm based on MSG SEVIRI sensor data, and Optimal Cloud Analysis product available via EumetCast transmission. Calibration is...
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High-precision bearing estimation for active sonar with cylindrical array performed by interpolated array transformation
PublikacjaThe article presents a method for improving the accuracy of bearing in multibeam sonar with a cylindrical array. The antenna’s non-linear shape and the resulting non-uniform sampling of the signal in space, mean that known methods of high-resolution spectral analysis cannot be used. In order to apply an algorithm from this group, a linear virtual antenna must be produced. The paper presents a technique of mapping a cylindrical...
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Optimizing of target detection and tracking processes realized on consoles of passive sonar with linear towed antenna
PublikacjaThe long-range passive towed sonar was first modernised a few years ago. Building on operator experience over that period, a concept was developed of optimising the tasks performed by sonar operators, and improving forms of imaging to inform about object detection and support object tracking. The concept was implemented and successfully tested during ships’ manoeuvres. The optimisation of operator tasks was designed to keep listening...
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Analysis of hydrodynamic pressure fields of motorboats and pontoons in shallow water
PublikacjaThe article presents the results of calculations of the pressure fields generated by a motorboat at the bottom of a shallow sea. Calculations were made using the boundary elements method (BEM), arranged on the surface of the boat and the bottom of the sea. This method is described in [3], and applied on a free surface linearized boundary condition. Results for four different lengths of motorboats, from 2.85 m to 9.5 m, sea depth...
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Methods for quality improvement of multibeam and LiDAR point cloud data in the context of 3D surface reconstruction
PublikacjaPoint cloud dataset is the transitional data model used in several marine and land remote-sensing applications. During further steps of processing, the transformation of point cloud spatial data to more complex models containing higher order geometric structures like edges and facets may be possible, if an appropriate quality level of input data is provided. Point cloud datasets usually contain a considerable amount of undesirable...
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Comparison between measured and calculated underwater pressure of merchant ship
PublikacjaFrom 2012 The Polish Naval Academy take part in an international research project SIRAMIS, carried out in the framework of the European Defence Agency. The objective of this project is to improve the understanding of ship signature interaction with multi influence sensors in relevant and realistic scenario's. This paper describes selected results of the comparison results of sea trials and model calculations of the hydrodynamic...
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Web-based 3D processing and dissemination of multibeam sonar data
PublikacjaThe continuous detailed surveys of the various water bodies over time produce a large and ever-increasing volume and density of underwater sounding data. Three-dimensional data, such as those obtained by multibeam sonar systems, are quite complex to manage, and thus their growing numbers increase the pressure on development of new solutions dedicated to processing them. This paper presents a concept system for web-based dissemination...
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Continuous wave sonar with hyperbolic frequency modulation keyed by pseudo-random sequence
PublikacjaA CW FM type sounding signal is used in the classical solution of silent sonar. While the signal provides a relatively simple implementation of digital signal processing, and ensures good detection conditions, unfortunately, in the presence of the Doppler effect, distance measurement results tend to be wrong. This is due to the fact that the received signal’s instantaneous frequency value is dependent both on the distance to the...
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Automatic Analysis of Trajectories of Moving Objects
PublikacjaOngoing monitoring is essential to providing security and safety of maritime and air operations. This paper presents the research in the area of automatic analysis of movement of unrestricted vehicles like ships and air-planes. The analysis is aimed at extraction of trajectory information, and the results can be used to identify anomalous behaviour in archived and real-time data. In this paper we focus on data acquired using the...
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3D Imaging Of Underwater Objects Using Multi-Beam Data
PublikacjaOne of the main applications of multibeam sonars is high resolution bathymetry measurement, as well as detecting and imaging of underwater objects like shipwrecks. In order to obtain the visualisation quality good enough to allow the researcher to investigate an object in more detail, the approach relying on construction of three-dimensional model of an imaged object, e.g. consisting of nodes, edges and plane elements (facets)...
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RADIATION OF HIGH INTENSITY SOUND BY CIRCULAR DISC BY MEANS OF THE NUMERICAL METHOD
PublikacjaThe main goal of this paper is to find sound pressure distribution radiated by the circular piezoelectric disc that vibrates with the finite amplitude. There has been presented the pressure distribution close to the radiating surface. Also it is shown the sound pressure distribution in the 3D form. The mathematic modeling was carried out on the base of the nonlinear acoustic equation with the proper boundary condition. The axial...
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Analysis of distance measurement errors in CW FM sonar with MLS code modulation
PublikacjaAlthough used in the classic silent sonar, the CW FM sounding signal has a major flaw which is its inaccuracy in determining the distance to a target. The authors of the article have developed a concept of silent sonar using frequency modulation signals switched by pseudorandom codes, already discussed in their previous work. This article presents a detailed analysis of errors in CW FM sonar with pseudo-random sequence code modulation...
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Chirp-rate estimation of FM signals in the time-frequency domain
PublikacjaNovel dynamic representations of a complex signal in the time-frequency domain including: a channelized instantaneous complex frequency (CICF), a complex local group delay (CLGD) and a channelized instantaneous chirp-rate (CICR) are introduced. The proposed approach is based on the use of the gradient of the short-time Fourier transform complex phase. An interpretation of the newly-introduced distributions especially of the CICR...
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INVESTIGATION OF BOTTOM SEDIMENT STRATIFICATION
PublikacjaThe main goal of this paper is to find a method to assess remotely the type of sediments on the basis of the signal received using the parametric echosounder. The images of the sea bottom sediments taken by a parametric echosounder show the fine structure of the upper layer of the bottom sediments. The depth of penetration depends on the type of sediment, in fact on the attenuation of acoustic wave. In the paper the method of distinguishing...
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The Doppler effect in a bistatic system for determining the position of moving targets
PublikacjaThe article presents the theoretical analysis and the results of numerical calculations of the Doppler effect it occurs in a system designed to determine the position and speed of a moving target. The transmitter is the source of the signal and it emits a sinusoidal, acoustic and continuous wave. Signal reflected off a moving target is received by four hydrophones. Based on the signals, four Doppler shifts are determined and inserted...
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Reliable underwater communication system for shallow coastal waters
PublikacjaThis paper presents a reliable and robust low data rate spread spectrum approach which is implemented in the acoustic underwater communication system for shallow coastal waters. It shows operation assumptions of spread spectrum techniques based on the wellknown Shannon equation. It describes two methods of spread spectrum: frequency hopping spread spectrum and direct sequence spread spectrum; their block diagram and their characteristics...
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The hydrodynamic pressure field of the ship Zodiak, measurements and calculations
PublikacjaThe article presents the results of measurements of the slowly changing hydrodynamic pressure field HPF generated by the movement of the ship, Zodiak, in the Bay of Gdansk. The measurement results have been obtained in the framework of the program of the work in Siramis, under the auspices of the European Defence Administration of the EU, by the research team of the Naval Academy in Gdynia. The measurement results were compared with...
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Modelling of acoustic backscattering by southern Baltic herring
PublikacjaAssessment of Baltic herring abundance can be carried out using acoustic techniques. Analysis of the relationship between the Baltic herring individual target strength, TS, and the total fish length, L, important for the acoustic assessment, showed the relationship to be dependent on the location of the study area. This finding motivated a detailed analysis of the relationship for the herring occurring in the southern Baltic...
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Study of swimbladder morphometry of Baltic herring and sprat (development of measurement methodology)
PublikacjaEffective management of Baltic clupeids, which are valuable commercially and ecologically,requires the biomass control. The acoustical techniques are recognized as effective in fishstock assessment. The study of Baltic herring and sprat individual backscatteringcharacteristics is required for the accurate biomass estimation using acoustical techniques.The previous measurements demonstrated significant...
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On the acoustic backscattering by Baltic herring and sprat
PublikacjaAccurate abundance estimate of Baltic clupeids, herring and sprat, is required for theirsustainable exploitation. The understanding the sound backscattering of individual fish isimportant for employing the acoustical techniques, which are widely used in the estimation.The previous studies demonstrated that the improvement of the understanding is critical forthe Baltic herring and sprat. It was the main...
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Backscattering properties of southern Baltic herring
PublikacjaReliable TS(L) relationship is required to improve acoustic algorithms of abundanceestimation of Baltic herring. The relationships, empirically obtained in different parts of theBaltic Sea, produce up to 8 dB – difference in the herring TS. In order to develop an accurateTS(L) relationship, it is important to analyze factors controlling the TS variability. Thepossible impact of the regional difference...
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MEMS Technology Evaluation for Submerged Vehicle Navigation
PublikacjaAnalysis of some vital aspects of inertial navigation using MEMS. The paper presents a few aspects of MEMS gyro errors, and their estimation process in the context of INS processing flow. These errors have a serious impact on overall inertial system performance. The results of undertaken researches in that area, and pointing out the main difficulties behind the INS when using a few top MEMS technologies, including sophisticated...