Filters
total: 1571
-
Catalog
displaying 1000 best results Help
Search results for: OPTYCZNY ELEMENT ROZPOZNAJĄCY
-
Impedance spectroscopy as a diagnostic tool of degradation of Solid Oxide Fuel Cells = Spektroskopia impedancyjna jako narzędzie diagnostyczne degradacji tlenkowych ogniw paliwowych
PublicationTlenkowe ogniwa paliwowe SOFC sa obecnie bliskie komercjalizacji. Wiedza na temat mechanizmów degradacji ogniw paliwowych jest niezbędna do dalszej poprawy ich działania. Spektroskopia impedancyjna jest skutecznym narzędziem diagnostycznym. Pozwala ona na wskazanie który element ogniwa SOFC ulega pogorszeniu oraz pozwala poznać dokładniej naturę procesu degradacji. W tej pracy degradacja ogniwa SOFC została zbadana przy użyciu...
-
Buckling of thin-walled columns accounting for initial geometrical imperfections
PublicationThe paper is devoted to the effect of some geometrical imperfections on the critical buckling load of axially compressed thin-walled I-columns. The analytical formulas for the critical torsional and flexural buckling loads accounting for the initial curvature of the column axis or the twist angle respectively are derived. The classical assumptions of theory of thin-walled beams with non-deformable cross-sections are adopted. The...
-
Elastic wave propapagation in diagnostics of self-drilling system of grouted anchors
PublicationThe paper presents an experimental investigation of elastic wave propagation in a self-drilling hollow bar system, which is commonly used in geotechnical industry as the element of grouted ground anchors and soil nails. The single self-drilling hollow bar and self-drilling system of two bars connected by a coupler were considered. Longitudinal waves were excited at one end of the bar and registered at both ends, by means of PZT...
-
Soil-structure interaction effects on modal parameters of office buildings with different number of stories
PublicationThe paper summarizes the results of a numerical investigation designed to study the soil-structure interaction effects on modal parameters of three office buildings. The reinforced-concrete 4-storey, 8-storey, and 12-storey office buildings, each with additional two levels of embedded basements, represent low, medium, and high-rise structures, respectively. In order to conduct this research, detailed finite-element structure models...
-
A Comparison of Simplified Two-dimensional Flow Models Exemplified by Water Flow in a Cavern
PublicationThe paper shows the results of a comparison of simplified models describing a two-dimensional water flow in the example of a water flow through a straight channel sector with a cavern. The following models were tested: the two-dimensional potential flow model, the Stokes model and the Navier-Stokes model. In order to solve the first two, the boundary element method was employed, whereas to solve the Navier-Stokes equations, the...
-
Dynamic electrochemical impedance spectroscopy of the adsorption and relaxation of polianiline chains during potentiodynamic redox transformations
PublicationZaprezentowano nowe podejście do analizy widm impedancyjnych uzyskanych dla warstwy przewodzącej polianiliny (PAni). Właściwości powyższej warstwy są często modelowane przy użyciu elementu stałofazowego (CPE), który w sposób dokładniejszy odzwierciedla wyniki eksperymentalne niż klasyczny element pojemnościowy (kondensator). W pracy zaproponowano nowy elektryczny obwód zastępczy oparty na modelu adsorpcyjnym Frumkin-Melik-Gaikazyan,...
-
Technical fabrics in costruction of large scale roofs - numerical and experimental aspects
PublicationDesigning and construction of textile hanging roofs is the challenging subject for engineers. This type of structure needs geometrically and very often also physically non-linear calculations. Due to different behaviour of two families of threads (warp and weft), which during deformation can change the angle between their directions, they require special constitutive modelling. Also the loading of hanging roofs is very special....
-
A current-controlled FET
PublicationA novel semiconductor device, viz., Horizontally-Split-Drain Current-Controlled Field-Effect Transistor (HSDCCFET) with two control electrodes is proposed in this works. For the sake of brevity, the device can be called a CCFET. Operating principle of the proposed transistor is based on one of the galvanomagnetic phenomena, the Biot-Savart-Laplace law and a Gradual Channel Detachment Effect (GCDE). The transistor is dedicated...
-
Multilevel model order reduction with generalized compression of boundaries for 3-d FEM electromagnetic analysis
PublicationThis paper presents a multilevel Model Order Reduction technique for a 3-D electromagnetic Finite Element Method analysis. The reduction process is carried out in a hierarchical way and involves several steps which are repeated at each level. This approach brings about versatility and allows one to efficiently analyze complex electromagnetic structures. In the proposed multilevel reduction the entire computational domain is covered...
-
Analiza wyboru czynnika niskotemperaturowego do siłowni Kogeneracji
PublicationW niniejszej pracy analizie numerycznej poddano obieg ORC, działający z wykorzystaniem grupy czynników niskowrzących suchych oraz mokrych. Rozważono dwie konfiguracje układu. Obieg z regeneracją ciepła dla czynników suchych: fc72, hfe7100, R134a, R227ea, R245fa, R423a, R600a oraz obieg bez regeneracji ciepła dla czynników mokrych R11, R12, R134a, R718. Obliczenia dokonane zostały przy założeniu wymaganej mocy cieplnej Q=50 kW,...
-
Czyste technologie gazowe - szansą dla Pomorza
PublicationW artykule przedstawiono koncepcję niskoemisyjnych obiegów gazowo-parowych rozwijanych w kierunku czystych technologii gazowych. Proponowane rozwiązania zakładają wykorzystanie pokładów gazu łupkowego znajdującego się na Pomorzu. Ze względu na ograniczoną wydajność otworu i skończony czas eksploatacji staje się zasadna utylizacja gazu w miejscu wydobycia w małych, przenośnych, kompaktowych elektrowniach z wykorzystaniem oksyspalania...
-
MOBILITY OF SHALE DRILL CUTTINGS CONSTITUENTS
PublicationThis study focuses on the abundance and mobility of metals and trace elements from shale drill cuttings into the water, being the main component of hydraulic fracturing fluid. The relationship between composition of the shale rock and the potential element release during standard water-based leaching tests was characterized by means of X-Ray Fluorescence spectroscopy (XRF). The XRF analysis confirmed the assumption of shales constituents...
-
The Effectiveness of Polymer Damper in Damage Reduction of Temporary Steel Grandstand
PublicationA large number of accidents involving damage of temporary grandstands during different types of events were observed in the past. The aim of the paper is to analyse numerically the effectiveness of a polymer damper in damage reduction of a temporary steel scaffolding grandstand exposed to dynamic load due to jumping. The element has been installed as a diagonal one at the back part of the structure. The method has been compared...
-
Three-point bending test of sandwich beams supporting the GFRP footbridge design process - validation
PublicationSome selected aspects concerning material and construction design issues for pedestrian footbridge made of GFRP composite materials are elaborated in this paper. The analysis is focused on validation tests, which are particularly important because of the advanced technology and materials that are used for this innovative bridge. The considered footbridge is a sandwich-type shell structure comprising of PET foam core and outer skins...
-
Thin-walled cross section shape influence on steel member resistance.
PublicationThis work describes why trending thin-walled technology is achieving popularity in steel construction sector. A purpose of this article is to present the influence of the cold-formed element cross-section shape on an axial compression and a bending moment resistance. The authors have considered four different shapes assuming constant section area and thickness. Calculations were based on three different steel grades taking into...
-
Adopting collaborative games into Open Kanban
PublicationThe crucial element of any agile project is people. Not surprisingly, principles and values such as "Respect for people", "Communication and Collaboration", "Lead using a team approach", and "Learn and improve continuously" are an integral part of Open Kanban. However, Open Kanban has not provided any tools or techniques to aid the human side of software development. Moreover, as a Lean initiative, it is not as comprehensively...
-
Calibration of precipitation estimation algorithm with particular emphasis on the Pomeranian region using high performance computing
PublicationFast 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...
-
Nested Space Mapping Technology for Expedite EM-driven Design of Compact RF/microwave Components
PublicationA robust simulation-driven methodology for rapid and reliable design of RF/microwave circuits comprising compact microstrip resonant cells (CMRCs) is presented. We introduce a nested space mapping (NSM) technology, in which the inner space mapping layer is utilized to improve the generalization capabilities of the equivalent circuit model corresponding to a constitutive element of the circuit under consideration. The outer layer...
-
Zwiększenie sprawności procesów technologicznych poprzez zastosowanie układów ORC i systemów trigeneracyjnych
PublicationPoprawa sprawności energetycznej procesów technologicznych - obok ograniczenia emisji gazów cieplarnianych i wykorzystania niekonwencjonalnych technologii do konwersji energii - stanowi obecnie najważniejszy element idei zrównoważonego rozwoju. Niniejsza praca wychodzi naprzeciw oczekiwaniom rynkowym, wskazując możliwości wpisania się w ten trend. Stanowi ona zbiór ogólnych wytycznych, opartych o literaturę przedmiotu i własne...
-
Zastosowanie założeń koncepcji efektuacji w organizowaniu wydarzenia kulturalnego – studium przypadku
PublicationThe paper presents how the effectuation model, which stems from the business studies, can be applied as a tool for analysing the activities undertaken as part of culture organisation. The key element of this model involves the control-based approach to the future instead of making predictions about the future. The outline of the theoretical background is followed by the results of the qualitative research, where the answers were...
-
Rewitalizujaca rola sztuki w miejskiej przestrzni publicznej
PublicationWspółcześnie sztuka stała się narzędziem rewitalizującym miejskie przestrzenie publiczne. Obserwacja przemian jakie dokonują się w miastach dzięki jej obecności powoduje, że dostrzegany jest w niej nie tylko element estetyzujący, ale także naprawczy. Następuje wykorzystywanie działań twórczych do pobudzania aktywności lokalnych społeczności. Zauważalne włączanie mieszkańców do działań partycypacyjnych z udziałem sztuki powoduje,...
-
Identifying Selected Tram Transport Risks
PublicationIn the area of transport infrastructure risks, infrastructure is inspected for safety. It is an element of transport safety management based on risk management and forms part of preventative activities and measures. As regards tram infrastructure which is a component of urban transport infrastructure, there are potential collisions with cars, cyclists and pedestrians. Data from Gdansk Buses and Trams...
-
Water uptake in protective organic coatings and its reflection in measured coating impedance
PublicationWater uptake in commercially available epoxy coating on mild steel using impedance spectroscopy and gravimetry was studied. The water content in the coating was determined using the Brasher-Kingsbury equation and various methods of coating capacitance calculation used in the literature. The obtained results were compared with reference gravimetric data. An overestimation of values obtained from impedance data in relation to gravimetric...
-
Design and Optimization of a Compact Planar Radiator for UWB Applications and Beyond
PublicationA compact monopole antenna for ultra-wideband (UWB) and beyond applications has been proposed. The radiator is based on the monopole topology. The super-wideband behavior has been achieved using a combination of spline-based modifications applied to the driven element, as well as utilization of a tapered feed and a slot-modified ground plane. The electrical performance of the structure has been tuned using a numerical optimization...
-
Efficient Fabry-Perot Open Resonator Analysis by the use of a Scattering Matrix Method
PublicationIn this paper a comparative study of the computational efficiency of two modeling methods applied to the analysis of the plano- and double-concave Fabry-Perot open resonators is presented. In both numerical approaches, a scattering matrix method was applied, which allows splitting the analysis of the resonator into several sections, including the one with a spherical mirror, which requires the largest computing resources. Two modeling...
-
Evaluation of the use of reindeer droppings for monitoring essential and non-essential elements in the polar terrestrial environment
PublicationExcess or toxic metals, non-metals and metalloids can be eliminated from the organism by deposition in inert tissue (e.g. fur) or excretion with body secretions, urine and faeces. Droppings are one of the main routes for the elimination of multiple elements and they can be collected without direct contact with the animal. Contaminant concentration has been examined in non-lethally collected tissues of several species (especially...
-
Określenie parametrów modelowania geometrii krzyżownic rozjazdów zwyczajnych dla potrzeb budowy i utrzymania linii kolejowych
PublicationZdecydowana większość rozjazdów występująca na liniach kolejowych w Polsce to rozjazdy zwyczajne o typowym zestawie parametrów. Z tego powodu analiza przypadków nietypowych (takich jak rozjazdy o zmiennej krzywiźnie toru zwrotnego) może być utrudniona. Wirtualny model geometryczno-konstrukcyjny rozjazdu, generowany w oparciu o metody analityczne, stanowić może narzędzie użyteczne w sferze projektowania, konstrukcji oraz diagnostyki...
-
Video traffic data - Interchange Lotnisko (S6-472) - weaving, Poland
Open Research DataThe data includes video traffic data registered with 9 video cameras at weaving area (weaving section type A) of the Lotnisko interchange within S6 expressway in Poland (interchange of expressway S6 and regional road 472), located in the Tri-City Agglomeration . The data covers the two days: 04.10.2017 (expressway S6) and 05.10.2017 (road 472).
-
ICT-enabled circular economy: conceptualising the links
PublicationThis chapter sets conceptual backgrounds regarding the potentially emerging causal links between digital technologies and circular economy ideas implementation. We argue that digital technologies may constitute an effective element enabling the transformation from linear to circular and environmentally friendly economic activities. This work draws the general picture at the macro and micro level. The macro perspective shows how...
-
Biomimetic torene shells
PublicationThe genome inside the eukaryotic cells is guarded by a unique shell structure, called the nuclear envelope (NE), made of lipid membranes. This structure has an ultra torus topology with thousands of torus-shaped holes that imparts the structure a high flexural stiffness. Inspired from this biological design, here we present a novel ‘‘torene’’ architecture to design lightweight shell structures with ultra-stiffness for engineering...
-
Visible light activity and photoelectrochemical properties of nitrogen-doped TiO2.
PublicationFotokatalizatory TiO2 domieszkowane azotem zostały zsyntetyzowane z propanolanu tytanu (IV) lub chlorku tytanu (IV) i tiomocznika. Żółte proszki otrzymane po ogrzewaniu w temperaturach 400-600 st.C fotokatalizowały mineralizację 4-chlorofenolu w zakresie światła widzialnego (delta większe lub równe 455nm. W odróżnieniu od uprzednio opublikowanych wyników, zsyntetyzowane fotokatalizatory nie zawierały siarki, lecz zamiast tego azot...
-
Numerical investigation of the core eccentricity effect on wave propagation in embedded waveguide
PublicationThe paper presents results of theoretical and numerical investigation of guided wave propagation in two-layer bars with geometric imperfections in the form of eccentric location of steel core. Steel rod of diameter equal to 1 cm embedded in composite mortar-type cover with external diameter equal to 5 cm has been taken into consideration. Several different rods with variable size of eccentricity are analysed. Results for rods with...
-
Multistage optical switching networks
PublicationEwolucja sieci szkieletowej w kierunku sieci DWDM o dużych szybkościach generuje nowe problemy dla kontynuacji. Ten element funkcjonalny musi także być oparty na technologii optycznej. Dla dużych pojemności nie może on być zrealizowany jako pojedynczy komutator, lecz jako wielosekcyjne pole komutacyjne. W artykule opisano trzy typy komutatorów: komutator światłowodów(FX), komutator długości fal (WSX) i komutator z konwersją długości...
-
Neural network model of ship magnetic signature for different measurement depths
PublicationThis paper presents the development of a model of a corvette-type ship’s magnetic signature using an artificial neural network (ANN). The capabilities of ANNs to learn complex relationships between the vessel’s characteristics and the magnetic field at different depths are proposed as an alternative to a multi-dipole model. A training dataset, consisting of signatures prepared in finite element method (FEM) environment Simulia...
-
Reliability model of slide bearings with particular attention given to lubricating oil
PublicationThe paper presents the slide bearing with circulating lubrication as a system of series three-element structure, where lubricating oil is the weakest link. In accordance with the Pierce statement that ''strength of chain is the strength of its weakest link'', a bearing reliability model has been developed. It allows to use the lubricating oil to evaluate the probability of correct working of the whole slide bearing, i.e. the reliability....
-
Behaviour of steel columns under impact
PublicationOne of import issues related to the idea of sustainable society is the safety of civil engineering structures. The safety and reliability of steel structures under impact loading is among a number of different aims during the design state. The aim of this paper is to present the results of investigation focused on dynamic behaviour of steel columns under impact loading. Modal and transient dynamic analyses using Finite Element...
-
The use of weight in motion data to heavy vehicles - pavement interaction analysis
PublicationWeight in motion (WIM) is the element of modern intelligent transport systems created to control commercial vehicles and to detect overloaded items. Because all of the vehicles crossing the WIM station are weighed and recognized, given data can be used to vehicle-pavement interaction analysis. The paper presents the results of analysis based on data from seven WIM stations localized in Motorway and National Roads in Poland. The...
-
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...
-
Acoustic Processor of the Mine Countermeasure Sonar
PublicationThis paper presents the concept of an acoustic processor of the mine countermeasure sonar. Developed at the Department of Marine Electronics Systems, Gdansk University of Technology, the acoustic processor is an element of the MG-89, an underwater acoustic station. The focus of the article is on the modules of the processor. They are responsible for sampling analogue signals and implementing the algorithms controlling the measurement...
-
Innovative method for utilization of wastewater for security and safety in rural areas
PublicationIn the rural areas building of sewerage systems and central wastewater treatment plants (WWTPs) often brings too high costs, due to high distances from one farm to another and terrain configuration. Individual treatment systems for each farm are a good solution. The teratment wetlands for nine individual farms were constructed in Kaszubian Lake District in summer and autumn 2009. Three configurations of reed beds were chosen. In...
-
A DISCRETE-CONTINUOUS METHOD OF MECHANICAL SYSTEM MODELLING
PublicationThe paper describes a discrete-continuous method of dynamic system modelling. The presented approach is hybrid in its nature, as it combines the advantages of spatial discretization methods with those of continuous system modelling methods. In the proposed method, a three-dimensional system is discretised in two directions only, with the third direction remaining continuous. The thus obtained discrete-continuous model is described...
-
Kształtowanie tożsamości na przykładzie małych miast województwa pomorskiego
PublicationSmall towns form an important element of the landscape, economy, both social and cultural life of our regions. Moreover, the way they develop determine regional indicators of the quality of life. These centers take today attempt to redefine its role and place in the spatial structures of the region, looking for new impulses and development opportunities to improve the living conditions of the local public. They have deeply divergent...
-
Dynamic analysis of temporary steel grandstand equipped with different types of bracing system
PublicationIn the paper, behaviour of a temporary steel grandstand equipped with two different types of bracing system has been analysed through the numerical study. A typical solution concerning application of a diagonal tubular members has been compared with elements proposed by authors and called polymer dampers. A polymer element consists of two L-shape steel members bonded with polymer mass. The aim of the paper is to verify the effectiveness...
-
Tacit Knowledge Sharing and Value Creation in the Network Economy: Socially Driven Evolution of Business
PublicationKey factors which affect competitive advantage in the network economy are innovation, relationships, cooperation, and knowledge. Sharing knowledge is not easy. Companies find it problematic. Presented studies show that the essence of the value creation today is not in sharing explicit but rather tacit knowledge, which is a source of creativity and innovation. Delivering value through knowledge does not only require efficient Transactive...
-
Global sensitivity analysis of membrane model of abdominal wall with surgical mesh
PublicationThe paper addresses the issue of ventral hernia repair. Finite Element simulations can be helpful in the optimization of hernia parameters. A membrane abdominal wall model is proposed in two variants: a healthy one and including hernia defect repaired by implant. The models include many uncertainties, e.g. due to variability of abdominal wall, intraabdominal pressure value etc. Measuring mechanical properties with high accuracy...
-
Minikanałowy płaszczowo-rurowy wymiennik ciepła
PublicationArtykuł dokumentuje kolejny etap prac poświęconych zagadnieniom skojarzonej produkcji energii cieplnej i elektrycznej za pomocą mikrosiłowni ORC, czyli produkcji dla pokrycia potrzeb indywidualnego odbiorcy. Jednym z głównych problemów w konstrukcji takiego urządzenia jest wysokosprawny wymiennik ciepła, stanowiący integralną część obiegu parowego ORC. Wymiennik ten winien charakteryzować się wysoką wydajnością cieplną osiąganą...
-
Applicability of an effective conductivity approach in modeling thoracic impedance changes
PublicationThis paper describes numerical simulations of the influence of conductivity changes inside a volume conductor on impedance changes measured on its surface. A simple model based on the finite element method has been developed to estimate an applicability of the effective conductivity theory in human chest modeling. The model consisted of a cylinder with two concentric spheres inside. Simulations were performed for two cases: first...
-
Selection of excitation signals for high-impedance spectroscopy
PublicationA method of fast impedance spectroscopy of technical objects with high impedance (|Zx| > 1 GOhm) is evaluated in this paper. An object is excited with a signal generated by a digital-to-analog converter (DAC) located on the U2531A DAQ module. Response signals proportional to current flowing through and voltage across the measured object are sampled by analog-to-digital converters (ADC) in the DAQ module. The object impedance spectrum...
-
Adhesive compliance effect in mode I separation:Profilometry approach
PublicationThe effect of adhesive compliance on the deflection of a loaded, bonded beam was studied using laser profilometry. Experimental data obtained were compared with both Euler-Bernoulli (encastré) and Winkler (one parameter elastic foundation) models. A third, analytical, 2D model, based on shear within the adhesive layer (two parameter elastic foundation), was introduced. Finite element analysis (FEA) was also used to study the effect...
-
Noncentrosymmetric superconductor with a bulk three-dimensional Dirac cone gapped by strong spin-orbit coupling
PublicationThe layered, noncentrosymmetric heavy element PbTaSe2 is found to be superconducting. We report its electronic properties accompanied by electronic-structure calculations. Specific heat, electrical resistivity, and magnetic-susceptibility measurements indicate that PbTaSe2 is a moderately coupled, type-IIBCSsuperconductor (Tc = 3.72 K, Ginzburg–Landau parameter κ = 17) with an electron-phonon coupling constant of λep = 0.74. Electronic-structure...