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Flow cytometric approach to evaluate the impact of hydro-technical concrete compounds’ release to the freshwater microbiome
PublikacjaThe aim of this research was to test the potential of applying a flow cytometric procedure to evaluate the impact of concrete compounds’ release to the freshwater microbiome. Cells from the collected samples were stained with a fluorogenic redox indicator dye that measures the redox potential of microbial cells. This novel approach was combined with the assessment of microorganisms’ penetration into the internal structures of concrete...
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Is the microfiltration process suitable as a method of removing suspended solids from rainwater?
PublikacjaDue to climate change and anthropogenic pressure, freshwater availability is declining in areas where it has not been noticeable so far. As a result, the demands for alternative sources of safe drinking water and effective methods of purification are growing. A solution worth considering is the treatment of rainwater by microfiltration. This study presents the results of selected analyses of rainwater runoff, collected from the...
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Improving the quality of speech in the conditions of noise and interference
PublikacjaThe aim of the work is to present a method of intelligent modification of the speech signal with speech features expressed in noise, based on the Lombard effect. The recordings utilized sets of words and sentences as well as disturbing signals, i.e., pink noise and the so-called babble speech. Noise signal, calibrated to various levels at the speaker's ears, was played over two loudspeakers located 2 m away from the speaker. In...
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Applying the Lombard Effect to Speech-in-Noise Communication
PublikacjaThis study explored how the Lombard effect, a natural or artificial increase in speech loudness in noisy environments, can improve speech-in-noise communication. This study consisted of several experiments that measured the impact of different types of noise on synthesizing the Lombard effect. The main steps were as follows: first, a dataset of speech samples with and without the Lombard effect was collected in a controlled setting;...
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Projekt stanowiska badawczego do wyznaczania charakterystyki ogólnej silnika spalinowego ZS przy wykorzystaniu hydraulicznego układu odbioru mocy
PublikacjaPrzedstawiono projekt stanowiska badawczego służącego do wyznaczania charakterystyki ogólnej silnika pojazdu ciężarowego, wykorzystując przystawkę odbioru mocy do napędu układu hydraulicznego generującego obciążenie silnika w różnych punktach jego pracy. Przedstawiono założenia projektowe oraz ograniczenia konstrukcyjne. Omówiono zasadę działania stanowiska i metodę wyznaczania charakterystyki. Opisano układ hydrauliczny oraz układ...
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STRATEGIA DOBORU PROCESU PRODUKCYJNEGO WG. REAKCJI NA ZAMÓWIENIA KLIENTA
PublikacjaW opracowaniu poruszono zagadnienie doboru strategii wytwarzania w zakresie procesu produkcyjnego. W ramach tego zagadnienia dokonano podziału procesów produkcyjnych wg różnych kryteriów. Skupiano się na podziale procesów wg. reakcji na zamówienia klienta. Przedstawiono pokrótce najistotniejsze cechy charakteryzujące tego typu procesy. By móc określić strategię w zakresie procesu produkcyjnego zestawiono kryteria wyboru procesu...
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Zastosowanie analiz i prognoz ruchu w programowaniu, planowaniu i projektowaniu inwestycji transportowych
PublikacjaW artykule zostanie przedstawiona charakterystyka procesu planowania i realizacji inwestycji transportowych ze szczególnym uwzględnieniem roli analiz i prognoz ruchu. Przedstawione fazy planowania, projektowania i realizacji inwestycji transportowych omówiono na przykładach wielu inwestycji prowadzonych w ostatnich latach na obszarze miasta Gdańska i województwa pomorskiego. Szczególną uwagę poświęcono roli analiz i prognoz ruchu...
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On Reduced-Cost Design-Oriented Constrained Surrogate Modeling of Antenna Structures
PublikacjaDesign of contemporary antenna structures heavily relies on full-wave electromagnetic (EM) simulation models. Such models are essential to ensure reliability of evaluating antenna characteristics, yet, they are computationally expensive and therefore unsuitable for handling tasks that require multiple analyses, e.g., parametric optimization. The cost issue can be alleviated by using fast surrogate models. Conventional data-driven...
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On ship roll resonance frequency
PublikacjaThe paper deals with the problem of modeling of rolling motion under a variety of excitation parameters. Special emphasis is put on the analysis and prediction of the frequency of the resonant mode of rolling, since it is often an essential issue in terms of motion of a ship related to her safety against capsizing or excessive amplitudes of roll. The research is performed for both free rolling and excited rolling and it is based...
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Multi-stage magnetic-fluid seals for operating in water - life test procedure, test stand and research results
PublikacjaThe edge criteria for magnetic-fluid seals durability research are critical for the seal'stechnological usefulness. The magnetic fluid seal technology in water is much moredifficult technological problem in comparison to gas or vacuum environment. There isalways problem with immediate contact between magnetic fluid and the environmentaluninspected liquids. In the paper are presented ways of experiments definitions carried outwith...
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Applicability of arrays of microjets heat transfer correlations to design compact heat exchangers
PublikacjaThe article presents experimental studies on a compact heat exchanger with heat transfer intensification by means of impinging microjets. The pursuit to provide high performance of heat exchangers is a response to the demand both in economics and in the universal tendency to miniaturization of industrial equipment. This paper presents the design and tests of a prototype, microjet heat exchanger. The modular design of the heat exchanger...
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Life tests of a rotary single-stage magnetic-fluid seal for shipbuilding applications
PublikacjaUse of the magnetic fluid seal technology in water is much more difficult technological problem in comparisonto gas or vacuum environment. Some seals constructed up to time been are designed as hybrid, two stagesealing structures with shields or mechanical seals used as protection measures to the magnetic fluid seal.Anyway, there is always problem with immediate contact between magnetic fluid and the environmentalliquid. In the...
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LCF behavior of 2024AA under uni- and biaxial loading taking into account creep pre-deformation
PublikacjaThis study presents the results of experimental low-cycle fatigue (LCF) tests of aluminum 2024 alloy T3511 temper in uni- and biaxial loading states. Tests were carried out on both the as-received material (hardened extruded rods) and material with different pre-deformation histories. These deformations were carried out in the creep process at 200 °C and 300 °C for two different levels of at each temperature. The pre-deformed material’s...
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A Wideband Rotary-Joint-Free H-Plane Horn Antenna With 360° Steerable Radiation Pattern Using Gap Waveguide Technology
PublikacjaConsidering the limitations of electronically steerable antennas such as limited steering span, gain degradation for large steering angles, complexity, and cost, this article is focused on the design of a simple mechanically steerable H-plane horn antenna. It is shown that since there is no need for an electrical connection between the top and bottom sections of a gap waveguide (GWG), if a sectoral horn is properly designed and realized...
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Low-frequency noise in Au-decorated graphene–Si Schottky barrier diode at selected ambient gases
PublikacjaWe report results of the current–voltage characteristics and low-frequency noise in Au nanoparticle (AuNP)-decorated graphene–Si Schottky barrier diodes. Measurements were conducted in ambient air with addition of either of two organic vapors, tetrahydrofuran [(CH2)4O; THF] and chloroform (CHCl3), as also during yellow light illumination (592nm), close to the measured particle plasmon polariton frequency of the Au nanoparticle...
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Rapid design closure of linear microstrip antenna array apertures using response features
PublikacjaA simple yet reliable approach to a rapid design closure of linear antenna array apertures at the electromagnetic (EM)-simulation level is proposed. Our methodology exploits an underlying array factor (AF) model suitably corrected by means of characteristic points (angles and levels) of the radiation pattern of the EM model of the antenna array aperture. This conveniently allows for controlling both the side lobe levels...
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Nonlinear Model of Synchronous Generator for Autonomous Electrical Power Systems Analysis
PublikacjaThis paper presents the nonlinear lookup table model for synchronous generator (SG) analysis. The saturation effects of the SG magnetic circuit have been considered. The saturated characteristic of the SG magnetic circuit are based on the open circuit saturation curve for magnetizing inductances. The model has been implemented into the Synopsys/Saber software using the MAST modelling language. To implement the no-load voltage characteristic...
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Novel doubly perforated broadband microstrip branch-line couplers
PublikacjaTwo broadband compact doubly perforated hybrid couplers have been designed, manufactured, and measured. To improve frequency characteristics and to reduce circuit dimensions, two kinds of perforations have been introduced: the defected ground structures in the ground plane metallization and photonic bandgap cells in the strip metallization. Measurement results show essential miniaturization (~39% and ~36%) and enhancement of the...
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A New Method of Noncausal Identification of Time-varying Systems
PublikacjaThe paper shows that the problem of noncausal identification of a time-varying FIR (finite impulse response) sys- tem can be reformulated, and solved, as a problem of smoothing of the preestimated parameter trajectories. Characteristics of the smoothing filter should be chosen so as to provide the best trade- off between the bias and variance of the resulting estimates. It is shown that optimization of the smoothing operation can...
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Alternative Energy: Photovoltaic Solar Cells
PublikacjaSolar radiation is a fuel for photovoltaic cells and modules, which are a source of electric energy. Viable solar technologies that have been developed in the past are starting to be adopted on a broader and more meaningful global scale across different sectors with ever-increasing market penetration. In this entry, a brief overview of the material properties relevant to solar cell operation, the structure of the solar cell, and electrical...
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Nowa metoda optymalizacji pracy ogniw paliwowych.
PublikacjaPrzedstawiono dynamiczną technikę impedancją jako doskonałe narzędzie służące do określenia optymalnych warunków pracy ogniw paliwowych. Możliwości tej techniki zostały przedstawione na przykładzie ustalenia optymalnej temperatury pracy. Otrzymane wyniki zostały skonfrontowane z charakterystykami prądowo napięciowymi ogniwa.
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Knowledge Flows in Cluster Organizations
PublikacjaThis paper aims to identify knowledge flows in cluster organizations (COs). On the basis of a literature analysis on knowledge flows and cluster organizations, the following research question was formulated: What kind of knowledge flows can be identified in cluster organizations and what is their main characteristics? The paper is based on a literature analysis and Grounded Theory methodology, examining four purposefully selected...
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Koncepcja, realizacja i analiza nowego typu silnika piezoelektrycznego o strukturze wielokomórkowej
PublikacjaDotychczasowe wyniki badań w obszarze aktuatorów piezoelektrycznych, wskazują ich potencjalnie duże możliwości w przyszłych zastosowaniach specjalnych. W artykule przedstawiono proces projektowania nowego typu silnika piezoelektrycznego. Opisane zostały wybrane topologie maszyn piezoelektrycznych. Przedstawiono wady i zalety silnika ultrasonicznego z falą biegnącą oraz silnika o ruchu obrotowym. W ramach realizacji projektu...
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NADBUDOWY I RENOWACJE ELEWACJI Z WYKORZYSTANIEM MATERIAŁÓW I ELEMENTÓW LEKKIEJ OBUDOWY
PublikacjaW artykule omówiono podział i charakterystykę lekkich przegród budowlanych. Przedstawiono możliwości zmian elewacji i wykonywania nadbudowy. Opisano kolejne kroki przygotowania inwestycji dotyczącej projektowania i realizacji nadbudowy obiektu budowlanego.
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Novel structure and size-reduction-oriented design of microstrip compact rat-race coupler
PublikacjaIn this paper, a novel structure of a miniaturized microstrip rat-race coupler has been proposed. Surrogate-based optimization procedures are applied to explicitly reduce the coupler size while maintaining equal power split at the operating frequency of 1 GHz and sufficient bandwidth for return loss and isolation characteristics. The optimization is performed using the objective function with four penalty components. The footprint...
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Selected Issues of Hybrid Outboard Motors
PublikacjaThe aim of the research reported in the article was designing a hybrid drive system based on an outboard internal combustion engine offered by a selected producer and testing its operating characteristics. The article presents different designs of this type of drive which can be found in the literature and are available in the market. The designed hybrid outboard drive system was tested both on the laboratory test rig and in real...
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3-phase medium frequency transformer for a 100kW 1.2kV 20kHz Dual Active Bridge converter
PublikacjaThe article presents a three-phase Medium Frequency Transformer being a part of a 100kW 1.2kV 20kHz Dual Active Bridge DC-DC converter. The transformer design is detailed focusing on winding and core power loss calculation. The high power three-phase MFT prototype is presented. The experimental results include the transformer impedance characteristics, no load test and three-phase DAB full load test waveforms
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Tinnitus Therapy Based on High-Frequency Linearization
PublikacjaThe aim of this work was to present problems related to tinnitus symptoms, its pathogenesis, hypotheses on tinnitus causes, and therapy treatments to reduce or mask the phantom noise. In addition, the hypothesis on the existence of parasitic quantization that accompanies hearing loss was recalled. The paper contains a description of experiments carried out with the application of high-frequency dither having specially formed spectral...
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Statistical Tuning of Walfisch-Ikegami Model for the Untypical Environment
PublikacjaThe Walfisch-Ikegami model has been investigated in terms of mobile radio systems designing in the untypical environment such as the maritime container terminal. The measurement equipment and procedures have been described as well as characteristics of investigated environment. Results of the statistical tuning in terms of path loss estimation in such environment have been analysed. The analysis has proved improvement of the path...
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Statistical Tuning of Walfisch-Ikegami Model for the Untypical Environment
PublikacjaThe Walfisch-Ikegami model has been investigated in terms of mobile radio systems designing in the untypical environment such as the maritime container terminal. The measurement equipment and procedures have been described as well as characteristics of investigated environment. Results of the statistical tuning in terms of path loss estimation in such environment have been analysed. The analysis has proved improvement of the path...
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Biometryczna kontrola dostępu
PublikacjaOpisano szczegółowo algorytm detekcji oraz identyfikacji człowieka na podstawie punktów nodalnych twarzy. Zdefiniowano pojęcia: biometria, proces pomiaru biometrycznego, metody biometrycznej identyfikacji oraz kontrola dostępu. Przedstawiono opis opracowanego systemu biometrycznej identyfikacji wykorzystującego sztuczne sieci neuronowe. Podano wyniki badań oraz przeprowadzono ich wnikliwą dyskusję.Biometrics is the study of automated...
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Facial features extraction for color, frontal images
PublikacjaThe problem of facial characteristic features extraction is discussed. Several methods of features extraction for color en--face photographs are discussed. The methods are based mainly on the colors features related to the specific regions of the human face. The usefulness of presented methods was tested on a database of en--face photographs consisting of 100 photographs.
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Simulation of Life Raft Motions on Irregular Wave - An Analysis of Situations Leading to Raft Capsizing
PublikacjaSuccessful rescue action at sea is based on a. o. a correct choice of rescue means and their reliability. Operational characteristics of life-saving appliances determine their performance in a given water area. Therefore they affect duration time of rescue action and decide this way on survival time of shipwrecked persons. This paper presents impact of characteristics of circular inflatable life rafts on their dynamics in a...
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Research on Linear Actuators for Active Foil Bearings
PublikacjaActive foil bearings are a kind of gas foil bearing. They contain actuators which allow for modification of the bearing sleeve size and the shape of the lubrication gap. Rotor vibrations can be actively controlled by these changes. It is possible, among other things, to reduce the starting torque, control the vibration amplitude at different speeds and improve operational safety. Prototypes of active foil bearings are being developed...
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INNOVATIVE THERMODYNAMICAL CYCLES BASED ON ENHANCEMENT MASS, MOMENTUM, ENTROPY AND ELECTRICITY TRANSPORT DUE TO SLIP, MOBILITY, TRANSPIRATION, ENTROPY AND ELECTRIC JUMPS AS WELL AS OTHER NANO-FLOWS PHENOMENA
PublikacjaIn our work, a further development of the authors model of thermo-chemical flow of fuel, air, oxygen, steam water, species, ionic and electron currents within nano channels and nano-structures of novel devices is presented. Different transport enhancement models are taken into account -among them the most important are: the velocity slip connected with complex external friction, the Darcy mobility and the Reynolds transpiration....
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Typology of low developed non-metropolitan sub-regions in the European Union
PublikacjaThis paper shows a typology of 319 NUTS-3 sub-regions in the European Union. The selected sub-regions are non-metropolitan sub-regions, whose gross domestic product per capita in 2011 was below 75% of the EU average. The objective of this typology was to recognize diversity in the examined sub-regions as a starting point for the selection of areas for future comparative research. The typology takes into account 24 variables related...
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Development of a compact microstrip resonant cell aimed at efficient microwave component size reduction
PublikacjaA comprehensive comparison of a wide collection of compact microstrip resonant cells (CMRCs) found in the extensive body of literature has been presented. The evaluation of different CMRC designs has led to the selection of the most promising CMRC geometry for the efficient miniaturisation of modern microwave components. In order to showcase the vital effectiveness of the approach, the initially selected CMRC has been notably...
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Evaluation of organic coatings condition with AFM-based method
PublikacjaThe paper presents an atomic force microscopy (AFM)-based approach to evaluation of local protective properties of organic coatings. Apart from topography, it provides local ac and dc characteristics of examined coating. The method consists in application of ac voltage perturbation signal between conductive AFM tip and coated metal substrate. The resulting current is used to determine local impedance characteristics. Both impedance...
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Light formed through urban morphology and different organism groups: First findings from a systematic review
PublikacjaThe prevailing implementation and usage of contemporary lighting technologies and design practices in cities have created over-illuminated built environments. Recent studies indicate that exposure to electric lighting effects formed through spatial characteristics has visual, physiological, and behavioural effects on both humans and non-humans, such as wildlife. In order to gain a better understanding of the impact that electric...
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Thermal and technological aspects of double face grinding of Al2O3 ceramic materials
PublikacjaDouble face grinding with planetary kinematics is a process to manufacture workpieces with plan parallel functional surfaces, such as bearing rings or sealing shims. In order to increase the economic efficiency of this process, it has to be advanced permanently. The temperature in the contact zone of most grinding processes has a huge influence on the process efficiency and the workpiece qualities. In contrast to most grinding...
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Synthesis and Characterization of Poly(zwitterionic) Structures for Energy Conversion and Storage
PublikacjaZwitterions are unique class of molecules that possess two functional groups bearing electric charges, one positive and second negative. This setup results in peculiar properties such as high water retention and anti-fouling capability. Therefore, zwitterionic coatings and gels are commonly applied in e.g. biosensing and bioelectronic devices. Despite those applications, there are other perspectives for zwitterionic materials....
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Stability analysis of interconnected discrete-time fractional-order LTI state-space systems
PublikacjaIn this paper, a stability analysis of interconnected discrete-time fractional-order (FO) linear time-invariant (LTI) state-space systems is presented. A new system is formed by interconnecting given FO systems using cascade, feedback, parallel interconnections. The stability requirement for such a system is that all zeros of a non-polynomial characteristic equation must be within the unit circle on the complex z-plane. The obtained...
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Application of electrochemical impedance spectroscopy to monitoring discharging process of nickel/metal hydride battery.
PublikacjaThis paper presents the possibility of applying impedance analysis to cell diagnostics. In order to obtain characteristic curves of both electrodes of a NiMH battery simultaneously, a reference electrode was added into the circuit. The authors analysed the cell under three cases, i.e. when its properties are determined only by the state of the positive electrode, only by the state of the negative electrode, or when both electrodes...
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REDUNDANCY AS A WAY INCREASING RELIABILITY OF SHIP POWER PLANTS
PublikacjaOne of key ways of assuring a high level of reliability of a ship power plant is to design redundancy of its structural elements, for example redundancy of prime drivers, drivelines etc. This paper deals with issues related to the redundancy as a way increasing dependability of the ship power and propulsion systems. Especially, fundamental characteristics of dependability, major design strategies influencing the reliability, and...
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A comprehensive evaluation of mimosa extract as a corrosion inhibitor on AA6060 alloy in acid rain solution: part I. Electrochemical AC methods
PublikacjaThe inhibition effect of mimosa extract on the corrosion of AA6060 aluminum alloy in acid rain solution was investigated by electrochemical impedance spectroscopy and dynamic electrochemical impedance spectroscopy (DEIS). All the studied electrochemical parameters showed good corrosion inhibitive characteristics with respect to the aluminum alloy in the tested solution. Inhibitor efficiency increased with the concentration and...
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An advanced thermal-FSI approach of an evaporation of air heat pump
PublikacjaThe paper presents selected problems of numerical modeling of an advanced thermal-FSI approach of evaporator of air heat pomp. The example of a fin-tube evaporator has been studied, focusing on obtaining of heat exchanger characteristics applying two-phase flow model for the in-tube refrigerant flow. Special attention is given to heat transfer between separated medium for different air velocity and changed refrigerant mass flow...
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Historical crane on the redesigned original trestle bridge as a memorial of Gdansk Shipyard
PublikacjaThe paper includes selected aspects of the study, whose goal is to hold the historical crane 642-24 in its current location after the modification of trestle bridge static scheme. The scope of the paper includes the assessment of current technical condition of the object, a presentation of FEM analyses, a description of the assumed load cases, results of the static calculations, checking the effort of construction elements, global...
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Resilient Routing in Communication Networks
PublikacjaThis important text/reference addresses the latest issues in end-to-end resilient routing in communication networks. The work highlights the main causes of failures of network nodes and links, and presents an overview of resilient routing mechanisms, covering issues related to the Future Internet (FI), wireless mesh networks (WMNs), and vehicular ad-hoc networks (VANETs). For each of these network architectures, a selection of...
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Tesla Friction-Type Micro Turbine For Small-Scale Cogeneration
PublikacjaTesla turbine is rarely used in professional power installations due to its specific work characteristics and relatively low internal efficiency. However, it has some potential to be applied in micro-power plants operating in distributed co-generation systems, also working in an organic Rankine cycle. This paper presents results from numerical calculations of flow in three models of Tesla disk turbines assuming nitrogen as a working...
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Non-matrix reference matrials- chalanges in the preparation of standard gas mixtures
PublikacjaIn the last few years particularly great pressure is exerted on quality control and assurance of analytical measurement results. An invaluable role in this process is played by reference materials. The paper presents the characteristics of basic types of reference materials, with particular attention to gaseous reference materials. In addition, a review of literature on techniques of preparation of gaseous standard materials, published...