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Search results for: ships, waves, white noise, damping, density, hull, seas, significant wave heights, testing, wave frequency
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Testing the usability of decisional DNA in robotics
PublicationW pracy poddano dyskusji i nalizie obszary mozliwych zastowac reprezentacji wiedzy zwanej Decisional DNA w zagadnieniach zwiazanych z robotyka.
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Vibration testing in buildings and safety of their operation
PublicationThe paper presents the issue of vibrations in residential buildings located near roads. It describes the measurement methodology and criteria for assessing the impact of vibrations generated by passing trucks. The article specifies a method to establish the impact on the operation of the examined facilities and it promotes the idea of employing a Bayesian network to determine probabilistically the level of risk to single-family...
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Testing and tuning PLC application programs
PublicationWe wstępie zawarto kilka uwag autora dotyczących pilnej potrzeby wdrażania na Wydziale Mechanicznym idei mechatronicznego kształcenia. Przedstawiono przegląd sposobów monitorowania i testowania programów aplikacyjnych PLC podczas budowania lub modernizacji systemów sterowania. Przedyskutowano zakres zastosowań oraz ograniczenia poszczególnych sposobów. Opisano przykład zastosowania zbudowanego stanowiska do eksperymentalnych testów...
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The novel sterilization device: the prototype testing
PublicationCurrently, there are numerous methods that can be used to neutralize pathogens (i.e., devices, tools, or protective clothing), but the sterilizing agent must be selected so that it does not damage or change the properties of the material to which it is applied. Dry sterilization with hydrogen peroxide gas (VHP) in combination with UV-C radiation is well described and effective method of sterilization. This paper presents the design,...
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A new approach to visual system testing
PublicationOpisano budowę laboratoryjnego stanowiska prac bawczych nad perymetrią obiektywną. Przedstawiono zasadę działania algorytmu VEPDA oraz wyniki działania VEPDA na danych eksperymentalnych.
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Influence of a Radio Frequency on RF Fingerprinting Accuracy Based on Ray Tracing Simulation
PublicationIn this paper the influence of a radio signal frequency on performance of Indoor Positioning System based on fingerprinting has been examined using ray-tracing simulations. It has been simulated how spatial distribution of an RF signal strength change with the signal’s frequency. The results were used to show its’ impact on the behavior of localization algorithms that are employing RSS measurements to determine node’s position...
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The changes of crosslink density of polyurethanes synthesised with using recycled component. Chemical structure and mechanical properties investigations.
PublicationThis paper aims at the utilisation of glycerolysate (Gly) obtained in polyurethane recycling process by means of crude glycerine, which has in its structure hydroxyl end groups that allow for further processing. Polyurethanes (PUs) were synthesised using prepolymer method with the mixture of neat polyol and glycerolysate, in different ratios, with 4,4-diphenylmethane diisocyanate (MDI). The prepolymer was subsequently extended...
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Noise of optoelectronic coupled devices
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Multimedia noise monitoring system
PublicationW artykule przedstawiono Multimedialny System Monitorowania Hałasu. Projekt jest sieciocentrycznym systemem dedykowanym monitorowaniu zagrożeń hałasem. Jego nadrzędnym celem jest zwiększenie skuteczności w zakresie profilaktyki chorób słuchu. Umożliwia pobieranie, gromadzenie, analizę i wizualizację danych dotyczących hałasu, pobieranych ze zdalnych urządzeń pomiarowych oraz elektronicznych ankiet dostępnych przez Internet. Ponadto...
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Railway noise problems in Poland
PublicationCelem referatu jest przedstawienie zagadnień związanych z hałasem kolejowym. W pierwszej kolejności podano przegląd badań związanych z hałasem kolejowym, które są prowadzone w polskich ośrodkach i instytucjach naukowych. Przytoczono również główne modele hałasu kolejowego zawarte w dyrektywach europejskich (projekty HARMONOISE i IMAGINE). Dodatkowo zaimplementowano wybrane modele hałasu kolejowego dla warunków polskiego taboru...
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The analysis of stationary electrochemical noise.
PublicationSzum elektrochemiczny jest techniką cieszącą się rosnącym zainteresowaniem. Jedną z podstawowych charakterystyk przebiegów otrzymywanych za pomocą omawianej metody jest widmowa gęstość mocy. Prawidłowa estymacja powyższej wielkości wiąże się z koniecznością zachowania wymogu stacjonarności szumu elektrochemicznego. W niniejszej pracy autorzy proponują zastosowanie rozkładu Wignera-Villego do oceny stopnia niestacjonarności przebiegów...
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Noise of optoelectronic coupled devices.
PublicationOpisano trzy systemy do pomiaru szumów transoptora a mianowicie: system do pomiaru szumów m. cz. diod LED, system do pomiaru szumów m. cz. fototranzystorów oraz system do pomiaru szumów m. cz. transoptorów. Przedstawiono wyniki pomiaru szumów m. cz. próby 13 transoptorów. Określono współczynnik korelacji między intensywnością szumów a wybranymi parametrami stałoprądowymi tych transoptorów.
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Noise of optoelectronic coupled devices.
PublicationOpisano dwa systemy do pomiaru szumów transoptorów. System do pomiaru szumów fototranzystora oraz system do pomiaru szumów transoptora. Przedstawiono porównanie wyników pomiarów szumów 27 transoptorów trzech różnych producentów.
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Integrated controller for ultra high frequency technique laboratory
PublicationDepartment of Microwave and Antenna Engineering decided to modernize the laboratory of Ultra High Frequency Techniques. The main change was to replace measurement of the field distribution inside rectangular waveguides by analysing the fields around striplines. This involved the need to overcome several technical and conceptual problems. Precise positioning of the probe and reading the field distribution near the stripline is important...
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Effect of band gap on power conversion efficiency of single-junction semiconductor photovoltaic cells under white light phosphor-based LED illumination
PublicationOn the basis of the detailed balance principle, curves of efficiency limit of single-junction photovoltaic cells at warm and cool white light phosphor-based LED bulbs with luminous efficacy exceeding 100 lm/W have been simulated. The effect of energy band gap and illuminance on the efficiencies at warm and cool light is discussed. The simulations carried out show that maximum power conversion efficiency at 1000 lx reaches 52.0%...
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Reduced-Cost Design Optimization of High-Frequency Structures Using Adaptive Jacobian Updates
PublicationElectromagnetic (EM) analysis is the primary tool utilized in the design of high-frequency structures. In vast majority of cases, simpler models (e.g., equivalent networks or analytical ones) are either not available or lack accuracy: they can only be used to yield initial designs that need to be further tuned. Consequently, EM-driven adjustment of geometry and/or material parameters of microwave and antenna components is a necessary...
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Pelvic vertical shear fractures: The damping properties of ligaments depending on the velocity of vertical impact load
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The finite-difference simulation of x-rays propagation through a system of lenses
PublicationThe propagation of X-ray waves through an optical system consisting of 33 aluminum X-ray refractive lenses is considered. For solving the problem, a finite-difference method is suggested and investigated. It is shown that very small steps of the difference grid are necessary for reliable computation of propagation of X-ray waves through the system of lenses. It is shown that the wave phase is a function very quickly increasing...
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Investigation of the Effect of The Temperature and Magnetization Pattern on Flux Density, Instantaneous Torque, Unbalanced Magnetic Forces of a Surface Inset PMM
PublicationElectrical machines utilized in domestic applications such as ceiling fans should have low losses and cost. Permanent magnets are used instead of rotor excitation to reduce losses. Therefore, not only the losses of the rotor winding are eliminated, but also the efficiency of the machine is increased. A surface inset consequent pole (SICP) machine has also been used to reduce costs. Because less magnets are utilized in this structure....
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<title>White-light interferometric temperature sensor for biomedical diagnostic</title>
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Determination of Stent Load Conditions in New Zealand White Rabbit Urethra
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White lie’ in medical practice from perspective of selected ethical theories
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Structural properties and adsorption of uranyl ions on the nanocomposite hydroxyapatite/white clay
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Theoretical study of the photoelectron spectrum of ethyl formate: Ab initio and density functional theory investigation
PublicationThe first ionization energy and associated photoelectron spectrum of ethyl formate are investigated with quantum chemistry calculations. The geometries, harmonic vibrational frequencies and first ionization energy are computed at the Hartree-Fock (HF) and at the second order Moller-Plesset perturbation theory (MP2). Moreover, accurate ionization energies are obtained with the Coupled-Cluster theory including singles and doubles...
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Endometrial nitric oxide production and nitric oxide synthases in the equine endometrium: Relationship with microvascular density during the estrus cycle
PublicationNitric oxide (NO) plays an important role in angiogenesis and in the regulation of the blood flow. This study was carried out to investigate (i) the effects of endogenous estrogens and progestins and exogenous progesterone (P(4)) (5 ng/ml or 1 microg/ml) or estradiol 17beta (E(2)beta) (50 pg/ml or 1 microg/ml) on in vitro endometrial NO synthesis; (ii) the presence of different isoforms of NO synthase;...
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A method of self-testing of an analog circuit terminated by an ADC in electronic embedded systems controlled by microcontrollers
PublicationA new self-testing method of analog parts terminated by an ADC in electronic embedded systems controlled by microcontrollers is presented. It is based on a new fault diagnosis method based on on-line (i.e. during measurement), transformations of voltage samples of the time response of a tested part to a square pulse - onto localization curves placed in the measurement space. The method can be used for fault detection and single...
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Social perception of technological innovations at sports facilities: justification for financing ‘white elephants’ from public sources? The case of Euro 2012 Stadiums in Poland
PublicationThe main purpose of the paper is to provide a monetary valuation of social benefits in connection with the hypothetical implementation of technological innovations at four Euro 2012 stadiums in Poland. Not only the construction of the sport’s arenas, but also the ongoing maintenance drain the pockets of Polish taxpayers. At the same time Euro 2012 stadiums remain underused, which familiarize the host cities with the concept of ‘white...
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A method for assessing hazards, risks and safety of damaged ships at sea
PublicationPrzedstawiono wybrane problemy związane z metodą oceny bezpieczeństwa statków, opartej na ocenie zachowania się statku i ocenie ryzyka, w warunkach eksploatacyjnych. Omówiono zakres oceny bezpieczeństwa i analizy ryzyka w odniesieniu do zagadnienia zachowania się statku uszkodzonego na morzu. Analiza ryzyka oparta jest na zastosowaniu elementów Formalnej Oceny Bezpieczeństwa FSA. Opisano główne kroki analizy ryzyka. Podano podstawowe...
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Influence of pitting corrosion on strength of steel ships and offshore structures
PublicationPraca dotyczy wpływu korozji wżerowej na własności mechaniczne stali o zwykłej i podwyższonej wytrzymałości oraz na wytrzymałość stalowych konstrukcji przy obciążeniach statycznych i quasi- statycznych. Artykuł oparty jest głównie na japońskich publikacjach. W próbie rozciągania, korozja wżerowa obniża nieznacznie obciążenie odpowiadające granicy plastyczności Re(nieznacznie) i wytrzymałości na rozciąganie Rm (silniej, redukuje...
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A performance-oriented risk-based method for safety assessment of ships
PublicationW pracy przedstawiono wybrane informacje na temat metody oceny bezpieczeństwa statków w warunkach krytycznych. Metoda łączy podejście oparte na ocenie osiągów statku z podejściem opartym o ocenę ryzyka wypadku. Analiza ryzyka w metodzie oparta jest na zastosowaniu elementów Formalnej Oceny Bezpieczeństwa FSA. Analiza ryzyka w metodzie dotyczy: identyfikacji zagrożeń, oceny zagrożeń, identyfikacji scenariuszy wypadku, oceny ryzyka,...
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Hydrodynamic aspects of unconventional propulsor design for small fast ships.
PublicationArtykuł przedstawia przegląd niekonwencjonalnych pędników dla małych, szybkich okrętów. Przegląd ten obejmuje pędniki strugowodne, śruby superkawitacyjne, śruby częściowo zanurzone oraz śruby kawitujące. Charakterystyczne cechy hydrodynamiczne tych pędników wymieniono i przedyskutowano, ze wskazaniem wad i zalet. Pokrótce przedstawiono dostępne metody projektowania i przedyskutowano ich oczekiwaną dokładność. Przegląd zilustrowano...
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Hydroacoustic ships berthing aid systems in Gdańsk north harbour
PublicationManewry dobijania statków do nabrzeży portowych są trudnymi operacjami, przy których należy uwzględniać m. in. na pływy, wiatry, widzialność, prędkość, masę statku, odległość od pirsu. Ewentualna kolizja z pirsem niesie poważne konsekwencje, szczególnie groźne dla wielkich statków a zwłaszcza tankowców. Referat prezentuje hydroakustyczne systemy kontroli manewrów statków wykonane przez zespół pracowników Katedry Systemów Elektroniki...
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A novel method of local chirp-rate estimation of LFM chirp signals in the time-frequency domain
PublicationIn the paper, novel dynamic representations of a complex signal in the time-frequency domain are introduced. The proposed approach is based on using the gradient of the short-time Fourier transform complex phase. A channelized instantaneous complex frequency (CICF) and a complex local group delay (CLGD) are included in the presented signal representations. An application of the newly-introduced distributions is demonstrated by...
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Features of load and wear of main propulsion devices on sea-going ships with piston combustion engines and their impact on changes in technical states of the systems
PublicationThe paper presents the specificity of operation of propulsion systems of seagoing ships which causes the need to control the load on them, especially on their engines called main engines. The characteristics of the load on the propulsion systems, especially on the main engines as well as on the shaft lines and propellers driven by the engines, along with the process of wear in tribological joints (sliding tribological systems)...
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An adaptive-noise Augmented Kalman Filter approach for input-state estimation in structural dynamics
PublicationThe establishment of a Digital Twin of an operating engineered system can increase the potency of Structural Health Monitoring (SHM) tools, which are then bestowed with enhanced predictive capabilities. This is particularly relevant for wind energy infrastructures, where the definition of remaining useful life is a main driver for assessing the efficacy of these systems. In order to ensure a proper representation of the physical...
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Enhanced Mobility and Large Linear Nonsaturating Magnetoresistance in the Magnetically Ordered States of TmNiC2
PublicationWe have studied the magnetic, magnetotransport, and galvanomagnetic properties of TmNiC2. We find that the antiferromagnetic and field induced metamagnetic and ferromagnetic orderings do not suppress the charge density wave. The persistence of Fermi surface pockets, open as a result of imperfect nesting accompanying the Peierls transition, results in an electronic carriers mobility of the order of 4 × 103 cm2 V−1 s−1 in ferromagnetic...
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A method of self-testing of analog circuits based on fully differential op-amps with theTCBF classifier
PublicationA new approach of self-testing of analog circuits based on fully differential op-amps of mixed-signal systems controlled by microcontrollers is presented. It consists of a measurement procedure and a fault diagnosis procedure. We measure voltage samples of a time response of a tested circuit on a stimulation of a unit step function given at the common-mode reference voltage input of the op-amp. The fault detection and fault localization...
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Post-Effort Changes in Autophagy- and Inflammation-Related Gene Expression in White Blood Cells of Healthy Young Men
PublicationAcute, strenuous physical exertion requiring high levels of energy production induces the production of reactive oxygen species and metabolic disturbances that can damage the mitochondria. Thus, selective autophagic elimination of defective mitochondria may improve resistance to oxidative stress and potentially to inflammation. The main goal of this study was to evaluate the impacts of intense effort on changes in the expression...
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Use of response surface methodology in characterization of properties of recycled high density polyethylene/ground tire rubber compositions
PublicationSearching for newways to utilize rubber and polymerwaste has been the focus of many studies conducted by research centers and companies worldwide. In this study, the influence of extrusion conditions on the properties of thermoplastic compositions containing post-production recycled high density polyethylene (PE-HD) and ground tire rubber (GTR) at 50:50 mass ratiowas examined. Response Surface Methodology (RSM) was used to determine...
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Recent Advances in Accelerated Multi-Objective Design of High-Frequency Structures using Knowledge-Based Constrained Modeling Approach
PublicationDesign automation, including reliable optimization of engineering systems, is of paramount importance for both academia and industry. This includes the design of high-frequency structures (antennas, microwave circuits, integrated photonic components), where the appropriate adjustment of geometry and material parameters is crucial to meet stringent performance requirements dictated by practical applications. Realistic design has...
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Improving sensitivity of residual current transformers to high frequency earth fault currents
PublicationFor protection against electric shock in low voltage systems residual current devices are commonly used. However, their proper operation can be interfered when high frequency earth fault current occurs. Serious hazard of electrocution exists then. In order to detect such a current, it is necessary to modify parameters of residual current devices, especially the operating point of their current transformer. The authors proposed...
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Numerical and experimental study on effect of boundary conditions during testing of stiffened plates subjected to compressive loads
PublicationThis study analyses the effect of boundary conditions during testing on the structural behaviour stiffened plates with different thicknesses subjected to compressive loads. The goal of the compressive tests is to analyse the ultimate strength of a stiffened plate. During the test, relevant physical quantities are measured and investigated. The supporting structure's behaviour is investigated by analysing the force-displacements...
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Multiple-channel frequency-adaptive active vibration control using SONIC
PublicationSONIC (self-optimizing narrowband interference canceller) is an acronym of a new approach to rejection of sinusoidal disturbances acting at the output of a discretetime stable linear plant with unknown and possibly timevarying dynamics. The paper presents two frequency-adaptive extensions of the multivariate SONIC algorithm. The efficacy of the proposed solutions is tested using our laboratory-scale active vibration control plant.
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MSIS sonar image segmentation method based on underwater viewshed analysis and high-density seabed model
PublicationHigh resolution images of Mechanically Scanned Imaging Sonars can bring detailed representation of underwater area if favorable conditions for acoustic signal to propagate are provided. However to properly asses underwater situation based solely on such data can be challenging for less than proficient interpreter. In this paper we propose a method to enhance interpretative potential of MSIS image by dividing it in to subareas depending...
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Influence of cathodic-protection-induced hydrogenation on mechanical properties of two ship hull plate steels
PublicationPrzedstawiono wyniki próby rozciągania i udarowej Charpy V dla stali zwykłej wytrzymałości (kategorii A) i podwyższonej wytrzymałości (kat. AH32) zarówno w stanie dostawy jak i po nawodorowaniu (protektor Zn w słonej wodzie). Nawodorowanie obydwu stali zwiększyło nieco granicę plastyczności (Re) i wydłużenie (A), nie zmieniając (atal A) lub nieco zmniejszając przewężenie (Z). Wpływ nawodorowania na udarność był ewidentnie pozytywny...
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Report vconcerning corrosion reasons of s/y Lunar hull surface and possible way of repair
PublicationDokonano oceny korozji kadłuba jednostki pływającej, przyczyn powstania korozji oraz zaproponowano sposoby naprawy miejsc skorodowanych.
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Improving the procedure of probabilistic load testing design of typical bridges based on structural response similarities
PublicationThis paper concerns load testing of typical bridge structures performed prior to operation. In-situ tests of a two-span post-tensioned bridge loaded with three vehicles of 38-ton mass each formed the input of this study. On the basis of the results of these measurements, an advanced FEM model of the structure was developed for which the sensitivity analysis was performed for chosen uncertainty sources. Three uncorrelated random...
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Deformation of an elastic second gradient spherical body under equatorial line density of dead forces
PublicationWe consider deformations of an elastic body having initially a spherical shape. Assumed deformation energy depends on the first and second gradient of displacements. We apply an equatorial line density of dead loads, that are forces per unit line length directed in radial direction and applied along the equator of the sphere. We restrict ourselves our analysis to the case of linearized second strain gradient isotropic elasticity...
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Application of guided waves in the evaluation of steel-concrete adhesive connection
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Anti-plane waves in an elastic thin strip with surface energy
PublicationWe consider anti-plane motions of an elastic plate taking into account surface energy within the linear Gurtin–Murdoch surface elasticity. Two boundary-value problems are considered that describe complete shear dynamics of a plate with free faces or with free and clamped faces, respectively. These problems correspond to anti-plane dynamics of an elastic film perfectly or non-perfectly attached to a rigid substrate. Detailed analysis...