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MODELLING OF TRANSIENT FLOW IN STORM SEWERS
PublikacjaThe paper focuses on the assessment of second-order explicit numerical scheme for unsteady flows in sewers. In order to simulate the pressurized flow the 'Preissmann slot' concept is implemented. For simulation of the transcritical flow the original and improved McCormack scheme is used. The calculated results are compared with numerical solutions and laboratory measurements published in the technical literature. Moreover, the...
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Modeling of event trees for the rapid scenario development
PublikacjaThe paper concerns the safety of ships in abnormal/damage conditions. Some conclusions following from the research associated with development of a method for safety assessment of ships in abnormal/damage conditions is presented in the paper. The method called SSAMADC (Ship Safety Assessment Method in Abnormal/Damage Conditions) is a risk-based method and is connected with application of the quantitative risk assessment QRA approach....
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Observation Value Analysis – Integral Part of Bayesian Diagnostics
PublikacjaThe decision making process, in general, is understood as a process of selecting one of the available solutions to the problem. One of possible approaches supporting the process is Bayesian statistical decision theory providing a mathematical model to make decisions of a technical nature in conditions of uncertainty. Regarding above, a detailed subject of the research is to analyze the value of the observation, which is a part...
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GRAPHICAL REPRESENTATION OF MUSIC SET BASED ON MOOD OF MUSIC. GRAFICZNA PREZENTACJA ZBIORU MUZYCZNEGO OPARTA NA ANOTACJI NASTROJU MUZYKI
PublikacjaOne of the features for music recommendation, which is useful and intuitive for music listen-ers, is “mood”. The paper presents an approach to graphical representation of mood of music pieces. Subjective evaluation based on listening tests is performed for assigning mood labels of 150 pieces of music and placing them on the 2D mood plane. As a result, a map of songs is created, where music excerpts with similar mood are organized...
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Evaluation of Praseodymium and Gadolinium Doped Ceria as a Possible Barrier Layer Material for Solid Oxide Cells
PublikacjaIn this work, nanocrystalline layers based on the Pr, Gd co-doped CeO2 were investigated. For the preparation of thin layers, lowtemperature spray pyrolysis technique was used. Different stoichiometries of the layers were produced for comparison on polished sapphire substrates. The microstructure of the prepared thin layers was studied by scanning electron microscopy (SEM), energydispersive X-ray spectroscopy (EDS) and X-ray diffractometry (XRD)....
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Electrophoretic co-deposition of Fe2O3 and Mn1,5Co1,5O4: Processing and oxidation performance of Fe-doped Mn-Co coatings for solid oxide cell interconnects
PublikacjaThe “in-situ” Fe-doping of the manganese cobalt spinel was achieved by electrophoretic co-deposition of Mn1,5Co1,5O4 and Fe2O3 powders followed by a two-step reactive sintering treatment. The effects on the coating properties of two different Fe-doping levels (5 and 10 wt.% respectively) and two different temperatures of the reducing treatment (900 and 1000 °C) are discussed. Samples with Fe-doped coatings demonstrated a lower...
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Simulation of large thrust-bearing performance at transient states, warm and cold start-up
PublikacjaThe start-up of a large hydrodynamic thrust bearing of a vertical hydrogenerator is one of the most critical situations during the lifetime of a bearing. Hydrodynamic load capacity is low due to low speed and higher thermal deformations of the pad. A new approach to the simulation of a hydrodynamic bearing is shown in this article. A combination of finite elements method and computational fluid dynamics is used to perform the transient...
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Structure and thermoelectric properties of bismuth telluride—Carbon composites
PublikacjaCarbon nanotubes and amorphous carbon have been introduced into a bismuth telluride matrix (0.15 and 0.30 wt.% ratio) to investigate the influence of the carbon on the composite’s thermoelectric properties. Composites with well-dispersed additives have been obtained by sonication and ball-milling methodology. Carbon nanotubes and an amorphous carbon addition led to a decrease in electric conductivity from 1120 S/cm to 77 S/cm....
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The ranks of Japanese industrial sectors: 2005-2011
PublikacjaThe purpose of the current study is to expand the previous study which analyzes the industrial sectors ranks of specific countries. More specifically, the study aims to conduct a comparison in terms of the ranks of Japanese industrial sectors on the specific analysis period. The analysis period of the study is 2005-2011. Using the previous study as a reference, the study employs the Input-Output (IO) approach as an analysis instrument....
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The guidelines and principles for planning and design of road restraint systems
PublikacjaThe project RID 3A Road Safety Equipment (RoSE) implemented by the Gdansk University of Technology within the RID programme, aims to conduct a comprehensive study and analyses of different vehicle containment systems (PN-EN 1317) and types of support structures (PN-EN 12767) and their performance. Within the project an analysis will be conducted of available research reports...
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The ranks of Japanese industrial sectors: 2005-2011
PublikacjaThe purpose of the current study is to expand the previous study which analyzes the industrial sectors ranks of specific countries. More specifically, the study aims to conduct a comparison in terms of the ranks of Japanese industrial sectors on the specific analysis period. The analysis period of the study is 2005-2011. Using the previous study as a reference, the study employs the Input-Output (IO) approach as an analysis instrument....
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Examination of the factors influencing binaural rendering on headphones with the use of directivity patterns
PublikacjaThis paper presents a study on the influence of the directional sound sources with the use of the directivity patterns. This contribution also includes a comparison to the work done by Wendt et al., where several directivity pattern designs used to gradually control the auditory source distance in a room were showed. While the tests of Wendt et al. were done by auralizing source and room using a loudspeaker ring in an anechoic...
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The use of mathematical models for diagnosis of activated sludge systems in WWTP
PublikacjaIn this study diagnosis of activated sludge systems in wastewater treatment plant (WWTP) was investigated. Diagnosis of technical objects can be realized in many ways. One of the divisions of the diagnostic methods include modelling with or without a model of the object. The first of these is the analysis of the symptoms for which, based on the parameter values, the abnormality in the diagnosed objects are sought. Another way is...
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Production of fuel briquette from solid waste biomass using natural resin as a binder
PublikacjaAbstract Background: This research aimed to evaluate the use of natural resin as a binder for the production of fuel briquette from solid waste biomass. Methods: Proximate analyses were made for fuel briquette prepared from solid waste biomass using natural resin as a binder in comparison with using starch as a binder. Results: The results for density, percent content of moisture, percent content of volatile matter, percent content...
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A Comparative Study of Fuzzy SMC with Adaptive Fuzzy PID for Sensorless Speed Control of Six-Phase Induction Motor
PublikacjaMulti-phase motors have recently replaced three-phase induction motors in a variety of applications due to the numerous benefits they provide, and the absence of speed sensors promotes induction motors with variable speed drives. Sensorless speed control minimizes unnecessary speed encoder cost, reduces maintenance, and improves the motor drive’s reliability. The performance comparison of the fuzzy sliding mode controller (FSMC)...
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An Aqueous Exfoliation of WO3 as a Route for Counterions Fabrication—Improved Photocatalytic and Capacitive Properties of Polyaniline/WO3Composite
PublikacjaIn this paper, we demonstrate a novel, electrochemical route of polyaniline/tungsten oxide (PANI)/WO3) film preparation. Polyaniline composite film was electrodeposited on the FTO (fluorine-doped tin oxide) substrate from the aqueous electrolyte that contained aniline (monomer) and exfoliated WO3 as a source of counter ions. The chemical nature of WO3 incorporated in the polyaniline matrix was investigated using X-ray photoelectron...
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A Comparative Study of Fuzzy SMC with Adaptive Fuzzy PID for Sensorless Speed Control of Six-Phase Induction Motor
PublikacjaMulti-phase motors have recently replaced three-phase induction motors in a variety of applications due to the numerous benefits they provide, and the absence of speed sensors promotes induction motors with variable speed drives. Sensorless speed control minimizes unnecessary speed encoder cost, reduces maintenance, and improves the motor drive’s reliability. The performance comparison of the fuzzy sliding mode controller (FSMC)...
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Production of fuel briquette from solid waste biomass using natural resin as a binder
PublikacjaBackground: This research aimed to evaluate the use of natural resin as a binder for the production of fuel briquette from solid waste biomass.Methods: Proximate analyses were made for fuel briquette prepared from solid waste biomass using natural resin as a binder in comparison with using starch as a binder.Results: The results for density, percent content of moisture, percent content of volatile matter, percent...
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The future of the logistician education in Poland and Ukraine: comparative analysis of the student’s opinion
PublikacjaBackground: A professional future is the next logical step after a student completes their chosen degree course. More frequently, even during their studies, young people seek opportunities to participate in various conferences, training courses, internships, work placements, and to travel abroad, etc. All of this has one main goal - to increase the student's attractiveness as a potential employee on the labour market. Thus, it...
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Wybrane aspekty modelowania uderzenia pojazdem dźwigara wiaduktu
PublikacjaW pracy przedstawiono różne zagadnienia związane z uderzeniem pojazdu w dźwigar wiaduktu. Omówiono wybór modelu obliczeniowego, na podstawie porównania wyników dla modelu dźwigara zespolonego, modelu dźwigara stalowego oraz modelu wiaduktu. Następnie opisano model dźwigara zespolonego zastosowany w analizie MES oraz metodę wyznaczania współczynników tłumienia Rayleigha. Symulację numeryczną uderzenia dźwigara wiaduktu przez koparkę...
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Wykorzystanie klasyfikacji funkcjonalnej usług do efektywnego zarządzania zasobami chmurowymi
PublikacjaWykazano jak istotnym problemem jest zarzadzanie chmurą obliczeniową, w tym alokacja zasobów do wykonania usług (workloadów) zgłoszonych przez użytkownika. Przeanalizowano problem podziału usług wdrażanych w środowiskach chmurowych na klasy określające ich funkcjonalność. Zaproponowano oryginalną metodę alokacji workloadów wykorzystującą wprowadzoną klasyfikację funkcjonalną oraz identyfikację tych klas na podstawie wielkości generowanego...
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Heat transfer in plate heat exchanger channels: experimental validation of selected correlation equations
PublikacjaThis study is focused on experimental investigation of selected type of brazed plate heat exchanger. The Wilson approach was applied in order to estimate heat transfer coefficients for the PHEx passages. The main aim of the paper was to experimentally check ability of several correlations published in the literature to predict heat transfer coefficients by comparison experimentally obtained data with appropriate predictions. The...
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Fracture mechanics model of cutting power versus widespread regression equations while wood sawing with circular saw blades
PublikacjaA comparison of the theoretical cutting power consumption results forecasted with the model (FM_CM model) which include work of separation (fracture toughness) in addition to plasticity and friction, and two widespread regression equations while wood sawing with circular saw blades has been described. in and cutting power consumption forecasted. In computations of the cutting power consumption during rip sawing of Scots pine wood...
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Empirical verification in industrial conditions of fracture mechanics models of cutting power prediction
PublikacjaA comparison of experimental results obtained in the industrial conditions at a sawmill located in the Baltic Natural Forest Region (PL) and theoretical cutting power consumption forecasted with the models which include work of separation (fracture toughness) in addition to plasticity and friction has been described. In computations of cutting power consumption during rip sawing of Scots pine wood (Pinus sylvestris L.) values of...
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Multicriteria Evolutionary Weather Routing Algorithm in Practice
PublikacjaThe Multicriteria Evolutionary Weather Routing Algorithm (MEWRA) has already been introduced by the author on earlier TransNav 2009 and 2011 conferences with a focus on theoretical application to a hybrid-propulsion or motor-driven ship. This paper addresses the topic of possible practical weather routing applications of MEWRA. In the paper some practical advantages of utilizing Pareto front as a result of multicriteria optimization...
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Promising Nanoparticle-Based Heat Transfer Fluids—Environmental and Techno-Economic Analysis Compared to Conventional Fluids
PublikacjaProviding optimal operating conditions is one of the major challenges for effective heating or cooling systems. Moreover, proper adjustment of the heat transfer fluid is also important from the viewpoint of the correct operation, maintenance, and cost efficiency of these systems. Therefore, in this paper, a detailed review of recent work on the subject of conventional and novel heat transfer fluid applications is presented. Particular...
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Dissociative electron attachment to benzoic acid (C7H6O2)
PublikacjaThe dissociative electron attachment (DEA) to benzoic acid (C6H5COOH) has been studied using an experimental crossed beam setup of a quadrupole mass spectrometer and a trochoidal electron monochromator. Relative partial cross sections for the DEA to produce negative ion fragments show the main channels for dissociation. The comparison of the present results with the ultraviolet photoelectron spectrum of benzoic acid [J. Meeks,...
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Analysis of EN 1993-1-6 guidelines about determining amplitudes of equivalent imperfections of steel cylindrical shells subjected to uniform external pressure
PublikacjaCivil engineering structures should be designed with reference to relevant standards. One of them is a Eurocode 3 standard EN 1993-1-6:2007: Design of steel structures Part 1-6: Strength and Stability of Shell Structures. According to this standard, the value of buckling load can be determined using different approaches: classical hand calculations (stress design) and geometrical and material non-linear analysis of an imperfect...
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DYNAMIC POSITIONING CAPABILITY ASSESSMENT BASED ON OPTIMAL THRUST ALLOCATION
PublikacjaThe article presents an efficient method of optimal thrust allocation over the actuators in a dynamically positioned ship, according to the DNV-ST-0111 standard, Level 1. The optimisation task is approximated to a convex problem with linear constraints and mathematically formulated as quadratic programming. The case study is being used to illustrate the use of the proposed approach in assessing the DP capability of a rescue ship....
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A Convenient Way to Methylated 2-Imidazolines. Syntheses of Fluorene and Triazine Cyclic Diamidines
PublikacjaOne N-methyl- and 4-substituted 2-imidazolines are described. Fluorene bisimidazolines were obtained in good yield (64-92%), starting from 2,7-dicyanofluorene and ammonium sulfide. In a two-step procedure the crude bisthioamide was reacted with excess diaminoalkane-ethanol (1:1 mixt.) in an oil bath. This new procedure is superior over std. methods. For the sake of comparison, a new triazine bisimidazoline (I) was prepd. by...
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A Substrate Integrated Waveguide (SIW) Bandpass Filter in A Box Configuration With Frequency-Dependent Coupling
PublikacjaThis letter presents the design of a microwave bandpass filter with frequency-dependent coupling implemented in substrate integrated waveguide (SIW) technology. The proposed filter implements a four-pole generalized Chebyshev filtering function with two transmission zeros. Resonators are arranged in an extended box configuration with dispersive coupling on a main signal path, which produces an extra zero in comparison to classical...
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Traffic Type Influence on Performance of OSPF QoS Routing
PublikacjaFeasibility studies with QoS routing proved that the network traffic type has influence on routing performance. In this work influence of self-similar traffic for network with DiffServ architecture and OSPF QoS routing has been verified. Analysis has been done for three traffic classes. Multiplexed ON-OFF model was used for self-similar traffic generation. Comparison of simulation results were presented using both relative and...
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Role of nitrogen in optical and electrical band gaps of hydrogenated/hydrogen free carbon nitride film
PublikacjaWe report the optical and electrical band gap energy of amorphous hydrogenated carbon nitride (a-HCNx) and carbon nitride (a-CNx) as a function of nitrogen concentration (N/C). The optical band gap of a-HCNx and a-CNx films has been determined by means of Ellipsometry and UV-VIS. Both optical and electrical band gaps increase with elevated nitrogen concentration. Experimentally obtained electrical band gap is compared with the...
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Microwave-assisted preparation of potato starch silicated with silicic acid
PublikacjaApplication of microwave irradiation for the silication of granular potato starch with silicic acid, and the properties of silicated starch were investigated. Potato starch was esterified on 20 min microwave irradiation of starch with silicic acid, applying the power of 450 or 800Wand, for comparison, on 120 min convectional heating of the reagent blend at 100 ◦C. The degree of esterification and the reaction efficiency did not...
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MEASUREMENT OF TEMPERATURE-DEPENDENT VISCOSITY AND THERMAL CONDUCTIVITY OF ALUMINA AND TITANIA THERMAL OIL NANOFLUIDS
PublikacjaIn this study results of simultaneous measurements of dynamic viscosity, thermal conductivity, electrical conductivity and pH of two nanofluids, i.e. thermal oil/Al2O3 and thermal oil/TiO2 are presented. Thermal oil is selected as a base liquid because of possible application in ORC systems as an intermediate heating agent. Nanoparticles were tested at the concentration of 0.1%, 1% and 5% by weight within temperature range from...
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High temperature drying of beech with content of tension wood
PublikacjaThe presented artcle is focused on comparison of tension and normal wood of beech (Fagus sylvatica L.) in a high-temperature drying process. Samples of 26 mm thickness were selected from sapwood zone with different angle of growth rings. The article evaluated properties of tension and normal wood before and after drying process. Properties which are monitored were moisture, moisture gradients, covering tests, colour changes and...
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Anti-plane surface waves in media with surface structure: Discrete vs. continuum model
PublikacjaWe present a comparison of the dispersion relations derived for anti-plane surface waves using the two distinct approaches of the surface elasticity vis-a-vis the lattice dynamics. We consider an elastic half-space with surface stresses described within the Gurtin–Murdoch model, and present a formulation of its discrete counterpart that is a square lattice half-plane with surface row of particles having mass and elastic bonds different...
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Optical activity and electro-optic effect of l-arginine doped KDP single crystals
PublikacjaWe have used the modified polarimetric methods to study optical activity (OA) in the potassium dihydrogenphosphate (KDP) crystals doped with 0.7, 1.4 and 3.8 wt% L-arginine (L-arg) amino acid. Crystals were grown by the temperature reduction method. Small changes of the absolute eigen waves ellipticity and OA values in doped crystals were noted. We have experimentally determined the signs of OA in the [1 00] and [01 0] directions...
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Pylon foundation of a cable stayed bridge at the motorway ring road of Wrocław
PublikacjaThe largest bridge of the motorway ring road of Wroclaw is a cable stayed bridge over the Odra river near Rędzin. Due to hydrogeological conditions of the ground it was not convenient to use standard bored piles of high length. Instead shorter piles were applied with additional improvement by cement injections at the pile toes. This decision was possible by extending ground investigation program and application of numerical modeling...
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The distributed model predictive controller for the nuclear power plant turbo-generator set
PublikacjaTypically there are two main control loops with PI controllers operating at each turbo-generator set. In this paper a distributed model predictive controller DMPC, with local QDMC controllers for the turbine generator, is proposed instead of a typical PI controllers. The local QDMC controllers utilize step-response models for the controlled system components. These models parameters are determined based on the proposed black-box...
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Heat transfer in plate heat exchanger channels: experimental validation of selected correlation equations
PublikacjaThis study is focused on experimental investigation of selected type of brazed plate heat exchanger. The Wilson approach was applied in order to estimate heat transfer coefficients for the PHEx passages. The main aim of the paper was to experimentally check ability of several correlations published in the literature to predict heat transfer coefficients by comparison experimentally obtained data with appropriate predictions. The...
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DMI measurements impact on a position estimation with lack of GNSS signals during Mobile Mapping
PublikacjaNowadays, Mobile Laser Scanning is common in use in addition to geodesy measurements. The data which are provided by the system characterizes with high precision and flexibility. To precise mapping, the accuracy of the data should be maintained. In Poland, according to the minister’s dispositions, the accuracy of the data should not exceeded 10 cm. With fully operated system it is easy to uphold, but there is a situation when a...
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Flexural buckling and post-buckling of columns made of aluminium alloy
PublikacjaThe paper concerns flexural buckling and initial post-buckling of axially compressed columns made of aluminium alloy described by the Ramberg-Osgood relationship. The non-linear differential equation of the problem is derived using the stationary total energy principle and the assumptions of classical beam theory within a finite range. The approximate analytical solution of the equation leading to the buckling loads and initial...
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Mrówczan sodu z nowym pakietem inhibitorów korozji jako ekologiczny środek do odladzania infrastruktury lotniczej.
PublikacjaPrzedstawiono wyniki badań korozji kadmowej powłoki na stali oraz korozji po zanurzeniu stopów metali w mrówczanie sodu z nowym pakietem inhibitorów korozji, zawierającym synergiczną kompozycję poliasparaginianu sodu oraz imidazolu. Ponadto wyznaczono zdolność penetracji lodu przez badany układ. Właściwo- ści opracowanej kompozycji odladzającej porównano z właściwościami środków dostępnych na rynku. Uzyskane wyniki wskazują, że otrzymany...
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Gustav Oelsner i Hugo Althoff. W poszukiwaniu godnych warunków zamieszkania w Altonie i Gdańsku
PublikacjaCelem artykułu jest porównanie aktywności zawodowej dwóch architektów miejskich odpowiedzialnych za przestrzenny i architektoniczny rozwój Gdańska i Altony - Hugona Althoffa i Gustava Oelsnera, oraz porównanie architektury i urbanistyki modernistycznych osiedli socjalnych. Celem porównania jest zbadanie, w jakim stopniu lokalne uwarunkowania i tradycja mogą być nośnikiem uniwersalnych ideałów modernizmu i indywidualnej ekspresji...
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Prowadzenie ruchu małego źródła kogeneracji gazowej według kryterium efektu ekonomicznego
PublikacjaCechą charakterystyczną źródeł gazowych jest ich duża elastyczność ruchowa, w porównaniu do większości źródeł konwencjonalnych i odnawialnych. Cecha ta może i powinna być wykorzystywana do poprawy wskaźników ekonomicznych obiektu. W tym celu należy przeanalizować możliwości jakie daje prowadzenie ruchu źródeł nie w standardzie pracy z wymuszeniem zapotrzebowania na ciepło, ale właśnie maksymalnie wykorzystując elastyczność ruchową...
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Prowadzenie ruchu małej elektrociepłowni gazowej według kryterium efektu ekonomicznego
PublikacjaCechą charakterystyczną źródeł gazowych jest ich duża elastyczność ruchowa, w porównaniu do większości źródeł konwencjonalnych i odnawialnych. Cecha ta może i powinna być wykorzystywana do poprawy wskaźników ekonomicznych obiektu. W tym celu należy przeanalizować możliwości jakie daje prowadzenie ruchu źródeł nie w standardzie pracy z wymuszeniem zapotrzebowania na ciepło, ale właśnie maksymalnie wykorzystując elastyczność ruchową...
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AUTOMATIC OPTIMIZATION OF ADAPTIVE NOTCH FILTER’S FREQUEN CY TRACKING
PublikacjaEstimation of instantaneous frequency of narrowband com- plex sinusoids is often performed using lightweight algo- rithms called adaptive notch filters. However, to reach high performance, these algorithms require careful tuning. The paper proposes a novel self-tuning layer for a recently intr o- ducedadaptive notch filtering algorithm. Analysis shows th at, under Gaussian random-walk type assumptions, the resultin g solution converges...
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Automatic Optimization Of Adaptive Notch Filter’s Frequency Tracking
PublikacjaEstimation of instantaneous frequency of narrowband com- plex sinusoids is often performed using lightweight algo- rithms called adaptive notch filters. However, to reach high performance, these algorithms require careful tuning. The paper proposes a novel self-tuning layer for a recently intr o- ducedadaptive notch filtering algorithm. Analysis shows th at, under Gaussian random-walk type assumptions, the resultin g solution converges...
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Assessment of Alterations in Settlement Patterns of Agricultural Landscape in the Example of Kashubia in Poland
PublikacjaTraditional agricultural landscapes are heavily exposed to change due to their relatively low agricultural productivity. However, they represent cultural values of great importance in maintaining the resilience of the environment and society. Although their cultural potential is important for sustainable development, it is still insufficiently recognized. The article fills this gap by examining old farmstead buildings as a distinguishing...