wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: EFFICIENCY, METHODOLOGY, MODEL, MINE, DRAINAGE, STOCHASTIC PROCESS
-
Synteza układu sterowania statkiem morskim dynamicznie pozycjonowanym w warunkach niepewności
PublikacjaNiniejsza monografia obejmuje zagadnienia związane z syntezą układu dynamicznego pozycjonowania statku w środowisku morskim z zastosowaniem wybranych nieliniowych metod sterowania. W ramach pracy autorka rozważała struktury sterowania z zastosowaniem wektorowej adaptacyjnej metody backstep oraz metod jej pokrewnych, takich jak regulatory MSS (ang. multiple surface sliding), DSC (ang. dynamic surface control), NB (ang. neural backstepping)....
-
Tome-lapse X-ray tomography imaging of flow patterns in versatile silo model
PublikacjaThe paper introduces a new versatile silo model that was especially designed for in situ X-ray tomography studies of silo discharge for various flow conditions, namely concentric and eccentric. The presented work focuses on organic granular materials where low fraction of short-grain white rice is mixed with spheroidal sorghum particles. The high-quality tomography images combined with adequate image processing strategy allows...
-
Phenotypic consequences of LYS4 gene disruption in Candida albicans
PublikacjaA BLAST search of the Candida Genome Database with the Saccharomyces cerevisiae LYS4 sequence known to encode homoaconitase (HA) revealed ORFs 19.3846 and 19.11327. Both alleles of the LYS4 gene were sequentially disrupted in Candida albicans BWP17 cells using PCR-based methodology. The null lys4Δ mutant exhibited lysine auxotrophy in minimal medium but was able to grow in the presence of L-Lys and α-aminoadipate, an intermediate...
-
MATHEMATICAL MODELING OF FLOOD MANAGEMENT SYSTEM IN THE CITY OF GDAŃSK, ORUŃSKI STREAM CASE STUDY
PublikacjaAim of the study This study analyses the efficiency of flood protection in a small urban catchment, based on a system of small reservoirs. Material and methods To assess the flood routing and surge reduction, a mathematical model of the river catchment was implemented. This was a lumped hydrological model, based on the SCS-CN method. Channel routing was performed, using kinematic wave equation. The sub-catchments have been determined...
-
Balanced Spider Monkey Optimization with Bi-LSTM for Sustainable Air Quality Prediction
PublikacjaA reliable air quality prediction model is required for pollution control, human health monitoring, and sustainability. The existing air quality prediction models lack efficiency due to overfitting in prediction model and local optima trap in feature selection. This study proposes the Balanced Spider Monkey Optimization (BSMO) technique for effective feature selection to overcome the local optima trap and overfitting problems....
-
Limiting distribution of the three-state semi-Markov model of technical state transitions of ship power plant machines and its applicability in operational decision-making.
PublikacjaThe article presents the three-state semi-Markov model of the process {W(t): t 0} of state transitions of a ship power plant machine, with the following interpretation of these states: s1 – state of full serviceability, s2 – state of partial serviceability, and s3 – state of unserviceability. These states are precisely defined for the ship main engine (ME). A hypothesis is proposed which explains the possibility of application...
-
Towards automating repairs of IT systems
PublikacjaThis paper presents formal description of working principles of the repair library, being the essential component of the Repair Management Framework (RMF), which aims at automating the process of repairing IT systems, and consists also of the Repair Management Model (RMM) and the Repair Management System (RMS). RMM introduces two mathematical models (model of monitoring and model of repair processes), general enough to cover the...
-
Wind Turbines Modeling as the Tool for Developing Algorithms of Processing their Video Recordings
PublikacjaIn the real world, many factors exist disturbing observation of the examined phenomena and causing various noises and distortions in recorded signals. It very often makes it difficult or even impossible to optimize various signal processing algorithms, through finding appropriate parameters. In this paper, we show an application, that retrieves wind turbine rotor speed from recorded video. Next, we describe the process of reduction...
-
Wind Turbines Modeling as the Tool for Developing Algorithms of Processing their Video Recordings
PublikacjaIn the real world, many factors exist disturbing observation of the examined phenomena and causing various noises and distortions in recorded signals. It very often makes it difficult or even impossible to optimize various signal processing algorithms, through finding appropriate parameters. In this paper, we show an application, that retrieves wind turbine rotor speed from recorded video. Next, we describe the process of reduction...
-
Non-places in the centre of the historic Main Town in Gdansk? – Design Thinking as a method of solving problems in cities
PublikacjaThe interiors of reconstructed extensive blocks of the historic Main Town in Gdansk are nowadays degraded areas, full of cars, with “holes” after never-finished archaeological excavations. It is not surprising that inhabitants avoid them. These are NON-PLACES. This situation prompts social movements to act. The first step towards the change was the interdisciplinary and transdisciplinary project of revitalization of one of the...
-
COMBINING FUNCTIONAL AND AESTHETIC ASPECTS OF DAYLIGHTING IN SUSTAINABLE ARCHITECTURE WITH THE USE OF DIGITAL DESIGN METHODS
PublikacjaThe aesthetics of modern architecture should relate to its origins and goals - the environment, function, sustainability and its users. One of the conditions that meet the criteria is the presence of daylight and the use of its potential. The contemporary digital tools that support the design process allow to controlling the use of difficult and capricious materials, such as daylight. They also combine daylighting aspects with...
-
Integration of Multi-Source Geospatial Data from GNSS Receivers, Terrestrial Laser Scanners, and Unmanned Aerial Vehicles
PublikacjaThe analysis based on geospatial data from different measurement systems now constitutes a complex numerical and practical enterprise. The dynamic development of modern technologies enables rapid and precise acquisition of such data. Nonetheless, the diversity of reference systems is today one of the main challenges for their correct interpretation. The combined use of the processed measurement results and archival data in paper...
-
Improving social competencies of architecture students through participatory design of marketplace regeneration
PublikacjaThe article discusses the involvement of architecture students in actual urban regeneration projects through participatory design and tray to respond question how it can improve students social competences, and benefit their future careers as architects and urban planners. By using the example of the student workshops conducted in 2019 at the Faculty of Architecture, GdanskTech, the article discusses the specific methods applied...
-
Optimization of biocorrosion resistance and mechanical properties of PM Ti–XAl–2Fe–3Cu alloys by response surface methodology
PublikacjaIn the current study, the biocorrosion resistance and mechanical properties of the Ti–XAl–2Fe–3Cu (wt%) (X = 6, 4, 2 wt%) alloy produced by powder compact extrusion of blended elemental powders were optimized by using the response surface methodology in order to gain the best combination of processing parameters. To run the optimization process, central composite design with three equal levels of oxygen, hydrogen and aluminum was...
-
A concept for reducing PM 10 emissions for car brakes by 50%
PublikacjaWith regard to airborne particles with an aerodynamic diameter of less than 10 μm (PM10), in countries in the European Union, the mass of brake emissions equals approximately 8–27% of the total traffic-related emissions. Using a research methodology combining tests at different scale levels with contact mechanics simulations and PM10 chemical characterization, the REBRAKE EU-financed project had the following aims: i) to demonstrate...
-
Isolation of Citrus lemon extracellular vesicles: Development and process control using capillary electrophoresis
PublikacjaA new and scalable method for the isolation of extracellular vesicles (EV) from Citrus lemon juice samples was developed. The methodology included preliminary preconcentration of the sample using ultrafiltration (UF) followed by size-exclusion chromatography (SEC) purification and final preconcentration of the eluates. Transmission electron microscopy and proteomic analysis showed that isolates contained exosome-like vesicles, exocyst-positive...
-
Modelowanie i symulacja ruchu pojazdu zabytkowego podczas hamowania
PublikacjaOpracowano model samochodu zabytkowego z wykorzystaniem metody masa-sprężyna, służącego do symulacji procesu hamowania pojazdu zabytkowego z możliwością pomiaru drogi hamowania. Konfiguracja sieci połączeń między punktami mas elementów zawieszenia oraz opony okazuje się mieć bardzo duży wpływ na zachowanie symulowanego samochodu podczas hamowania. Poprawność symulacji sprawdzono porównując wyniki uzyskane z symulacji oraz z pomiarów...
-
Numerically efficient algorithm for compact microwave device optimization with flexible sensitivity updating scheme
PublikacjaAn efficient trust-region algorithm with flexible sensitivity updating management scheme for electromagnetic (EM)-driven design optimization of compact microwave components is proposed. During the optimization process, updating of selected columns of the circuit response Jacobian is performed using a rank-one Broyden formula (BF) replacing finite differentiation (FD). The FD update is omitted for directions sufficiently well aligned...
-
Pre-analytical aspects in metabolomics of human biofluids – sample collection, handling, transport, and storage
PublikacjaMetabolomics is the field of omics research that offers valuable insights into the complex composition of biological samples. It has found wide application in clinical diagnostics, disease investigation, therapy prediction, monitoring of treatment efficiency, drug discovery, or in-depth analysis of sample composition. A suitable study design constitutes the fundamental requirements to ensure robust and reliable results from the...
-
Computer -Aided Local Energy Planning Using ALEP-PL Software
PublikacjaThe issue of energy system planning, including the planning of local energy systems, is critical, since it affects the security of energy supplies in communities, regions, and consequently the security of energy supply within the country. Energy planning is a complex process that requires integration of different goals i.e. improvement of energy efficiency, increase in the share of renewables in the energy balance and CO2} emission...
-
Low-Cost and Highly-Accurate Behavioral Modeling of Antenna Structures by Means of Knowledge-Based Domain-Constrained Deep Learning Surrogates
PublikacjaThe awareness and practical benefits of behavioral modeling methods have been steadily growing in the antenna engineering community over the last decade or so. Undoubtedly, the most important advantage thereof is a possibility of a dramatic reduction of computational expenses associated with computer-aided design procedures, especially those relying on full-wave electromagnetic (EM) simulations. In particular, the employment of...
-
On design and analysis of flow characteristics of the last stage of gas-steam turbine
PublikacjaResearch regarding blade design and analysis of flow have been conducted for over a century. Meanwhile new concepts and design approaches were created and improved. Advancements in information technologies allowed to introduce computational fluid dynamics (CFD) and computational flow mechanics (CFM). Currently a combination of mentioned methods is used for design of turbine blades. These methods enabled us to improve flow efficiency...
-
Carboxylic acids as efficient corrosion inhibitors of aluminium alloys in alkaline media
PublikacjaThe efficiency of AA5754 aluminium alloy corrosion inhibition achieved with maleic, malic, succinic, tartaric, citric, tricarballylic acids and serine in alkaline environment (pH 11) was examined. Selected corrosion inhibitors are characterized by different numbers and distribution of carbonyl and hydroxyl groups within their molecules. We have proposed and verified a novel approach for determining the adsorption isotherms based...
-
Particle Swarm Optimization Based Optimal Design of Six-Phase Induction Motor for Electric Propulsion of Submarines
PublikacjaRecent research reveals that multi-phase motors in electric propulsion systems are highly recommended due to their improved reliability and efficiency over traditional three phase motors. This research presented a comparison of optimal model design of a six phase squirrel cage induction motor (IM) for electric propulsion by using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). A six phase squirrel cage induction...
-
Particle Swarm Optimization Based Optimal Design of Six-Phase Induction Motor for Electric Propulsion of Submarines
PublikacjaAbstract: Recent research reveals that multi-phase motors in electric propulsion systems are highly recommended due to their improved reliability and efficiency over traditional three phase motors. This research presented a comparison of optimal model design of a six phase squirrel cage induction motor (IM) for electric propulsion by using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). A six phase squirrel cage induction...
-
Adsorption behavior and corrosion inhibitive characteristics of newly synthesized cyano-benzylidene xanthenes on copper/sodium hydroxide interface: Electrochemical, X-ray photoelectron spectroscopy and theoretical studies
PublikacjaElegant process for synthesis of 3-(7H-dibenzo[c,h]xanthen-7-yl)benzaldehyde (3), as new starting material to create a set of novel xanthene analogues, 2-(3-(7H-dibenzo[c,h]xanthen-7-yl)benzylidene)malononitrile (4), 3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylic acid (5), and Ethyl-3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylate (6), was achieved starting with available materials under mild conditions. Various...
-
Measurement Campaign and Mathematical Model Construction for the Ship Zodiak Magnetic Signature Reproduction
PublikacjaThe paper presents the partial work done within the framework of the EDA Siramis II project focused on magnetic signature reproduction of ships. Reproduction is understood here as the ability to determine the magnetic anomaly of the local Earth magnetic field in any direction and at any measurement depth due to the presence of the analysed object. The B-91 type hydrographic ship Zodiak was selected as the real case study. The work...
-
Job satisfaction in the multicultural environment of multinational corporations
PublikacjaPurpose – Since prior research into the effects of multiculturalism on job satisfaction in multinational corporations (MNCs) is rather scant and inconclusive, the authors attempt to review the literature and explain why these results are inconsistent as well as propose a new model aimed at responding to these irregularities. Design/methodology/approach – In the narrative review of the prior research and the proposed model the...
-
Resource constrained neural network training
PublikacjaModern applications of neural-network-based AI solutions tend to move from datacenter backends to low-power edge devices. Environmental, computational, and power constraints are inevitable consequences of such a shift. Limiting the bit count of neural network parameters proved to be a valid technique for speeding up and increasing efficiency of the inference process. Hence, it is understandable that a similar approach is gaining...
-
Ti/TiO2 nanotubes sensitized PbS quantum dots as photoelectrodes applied for decomposition of anticancer drugs under simulated solar energy
PublikacjaOne of the challenges in research into photoelectrocatalytic (PEC) degradation of pollutants is finding the appropriate photoanode material, which has a significant impact on the process efficiency. Among all others, photoelectrodes based on an ordered TiO2 nanotube arrays are a promising material due to well-developed surface area and efficient charge separation. To increase the PEC activity of this material, the SILAR method was...
-
Numerical Simulations of Hydrodynamic Open-Water Characteristics of a Ship Propeller
PublikacjaThe paper presents the results of numerical simulations of ship propeller operation bearing the name of Propeller Open Water (POW) Tests. The object of tests was a sample ship propeller (PPTC1), the geometrical and kinematic data of which are available, along with the results of model tests, on the official page of the research centre involved in the measurements. The research aimed at verifying the correctness of results of numerical...
-
Model Correction and Optimization Framework for Expedited EM-Driven Surrogate-Assisted Design of Compact Antennas
PublikacjaDesign of compact antennas is a numerically challenging process that heavily relies on electromagnetic (EM) simulations and numerical optimization algorithms. For reliability of simulation results, EM models of small radiators often include connectors which—despite being components with fixed dimensions—significantly contribute to evaluation cost. In this letter, a response correction method for antenna models without connector,...
-
Influence of Properties of Hydraulic Fluid on Pressure Peaks in Axial Piston Pumps’ Chambers
PublikacjaThe article concentrates on the research of the pressure peaks in a working chamber of an axial piston pump. The main focus of the article is the influence of fluid properties on the pressure peaks value. Experimental and analytical methods were used to determine the impact of the fluid density, viscosity, compressibility and aeration. The article describes the pressure peak generation process and explains the theoretical basis...
-
Modeling the Effects of Slowly Biodegradable Substrate at Large WWTP in Northern Poland
PublikacjaThe essential study was divided into two parts: experimental investigation and mathematical modeling using special platform to computer simulations. In the first part of research an innovative measurement procedure for an indirect determination of the effect of biodegradable particulate and colloidal Xs substrate was developed and implemented. The results of laboratory tests were used futher to verify the mechanism of the hydrolysis...
-
Accelerated simulation-driven design optimisation of compact couplers by means of two-level space mapping
PublikacjaIn this study, the authors discuss a robust and efficient technique for rapid design of compact couplers. The approach exploits two-level space mapping (SM) correction of an equivalent circuit model of the coupler structure under design. The first SM layer (local correction) is utilised to ensure good matching between the equivalent circuit and the electromagnetic model at the component level. Subsequent global correction allows...
-
Self–Organizing Map representation for clustering Wikipedia search results
PublikacjaThe article presents an approach to automated organization of textual data. The experiments have been performed on selected sub-set of Wikipedia. The Vector Space Model representation based on terms has been used to build groups of similar articles extracted from Kohonen Self-Organizing Maps with DBSCAN clustering. To warrant efficiency of the data processing, we performed linear dimensionality reduction of raw data using Principal...
-
Self-Organizing Map representation for clustering Wikipedia search results
PublikacjaThe article presents an approach to automated organization of textual data. The experiments have been performed on selected sub-set of Wikipedia. The Vector Space Model representation based on terms has been used to build groups of similar articles extracted from Kohonen Self-Organizing Maps with DBSCAN clustering. To warrant efficiency of the data processing, we performed linear dimensionality reduction of raw data using Principal...
-
Multiscalar Control Based Airgap Flux Optimization of Induction Motor for Loss Minimization
PublikacjaBased on the induction motor model, considering the core loss resistance that accounts for magnetic characteristic saturation, a speed control approach is devised with an adaptive full-order (AFO) speed observer. The induction motor model analysis is done sincerely in a stationary reference frame. The control approach incorporates a flux reference generator designed to meet optimal operational circumstances and a nonlinear speed...
-
Landfill leachate treatment at a pilot plant using hydrophyte systems
PublikacjaConstructed wetlands can provide an effective and economical solution to landfill leachate treatment. In the article the performance of a CW for leachate treatment, consisting of two horizontal flow constructed wetlands (HF-CW) beds, working at the municipal landfill in Gdansk-Szadolki in the period 2004-2005 is being discussed. The plant has been operating since 2001. Clogging problems and surface flow occurred in the system...
-
Biotrickling filtration of n-butanol vapors: process monitoring using electronic nose and artificial neural network
PublikacjaBiotrickling filtration is one of the techniques used to reduce odorants in the air. It is based on the aerobic degradation of pollutants by microorganisms located in the filter bed. The research presents the possibility of using the electronic nose prototype combined with artificial neural network for biofiltration process monitoring in terms of reduction in n-butanol concentration and odour intensity of treated air. The study...
-
The effect of full-cell impregnation of pine wood (Pinus Sylvestris L.) on the fine dust content during sawing on a frame sawing machine
PublikacjaIn this paper the results of the analysis of the effect of the impregnation treatment of pine wood on the granularity of sawdust from the sawing process on the frame sawing machine PRW 15M are presented. Granulometric analyses of chips from impregnated and unimpregnated pine wood implies that the impregnation of pine wood does not affect the size and structure of the sawdust produced. A major ≈ 95% share of the formed chips is...
-
A new model of fuel spray shape at early stage of injection in a marine Diesel engine
PublikacjaIn the cylinders of a marine diesel engine, self-ignition occurs in very shortly time after the fuel injection into the combustion chamber. Therefore, the paper present was to develop a model of diesel fuel spray for the early stage of fuel spray for in marine diesel engine. There were taken into consideration the main aspects technical such as nozzle diameter of marine engine injector and backpressure in combustion chamber. In...
-
APPLICATION OF THE THEORY OF SEMI-MARKOV PROCESSES TO DETERMINE A LIMITING DISTRIBUTION OF THE PROCESS OF CHANGES OF ABILITY AND INABILITY STATES OF FUEL SUPPLY SYSTEMS IN HEAVY FUEL DIESEL ENGINES
PublikacjaThe paper presents applicability of the theory of semi-Markov processes to determine a limiting distribution of the process of changes of technical states of fuel systems for marine engines running on heavy fuel oils. The proposed study of this process includes the components of such fuel systems like: 1 - injectors, 2 - high pressure hoses, 3 - injection pumps, 4 - low pressure hoses, 5 – fine filters, 6 - coarse filters, 7 – fuel-feed...
-
The Influence of Low-Temperature Disintegration on the Co-Fermentation Process of Distillation Residue and Waste-Activated Sludge
Publikacja: Innovative low-temperature disintegration (process temperature 55 ◦C and oxygen concentration 0.2 mg/dm3 ) can be an economically rational technology to intensifying energy production from renewable sources. The proposed process can achieve a degree of disintegration—under optimal conditions—of about 50%, which is excellent when compared with other methods of feed pre-treatment. The low-temperature disintegration of distillation...
-
Neural Network-Based Sequential Global Sensitivity Analysis Algorithm
PublikacjaPerforming global sensitivity analysis (GSA) can be challenging due to the combined effect of the high computational cost, but it is also essential for engineering decision making. To reduce this cost, surrogate modeling such as neural networks (NNs) are used to replace the expensive simulation model in the GSA process, which introduces the additional challenge of finding the minimum number of training data samples required to...
-
Pin Angle Thermal Effects on Friction Stir Welding of AA5058 Aluminum Alloy: CFD Simulation and Experimental Validation
PublikacjaThe friction stir welding (FSW) of tool pin geometry plays a critical role in the final properties of the produced joint. The tool pin geometry directly affects the generation of heat and the flow of internal materials during the FSW process. The effects of the FSW tool pin angle on heat generation and internal flow have not been quantitatively investigated in detail. In this manuscript, a validated Computational Fluid Dynamic...
-
Oddziaływania taboru na mosty kolejowe przy zmiennych parametrach ruchu
PublikacjaW pracy poruszono zagadnienia związane z identyfikacją oraz modelowaniem układu dynamicznego most-pojazd ruchomy. Za element szczególnie istotny uznano czynnik obciążający. Opracowano i wdrożono metodykę identyfikacji cech dynamicznych rzeczywistego pojazdu szynowego. Eksperyment badawczy przeprowadzono dla jednostki trakcyjnej EN57, jednak nie ma żadnych ograniczeń w stosowaniu metody dla innego, konwencjonalnego taboru szynowego....
-
Organic Acids and Polyphenols Determination in Polish Wines by Ultrasound-Assisted Solvent Extraction of Porous Membrane-Packed Liquid Samples
PublikacjaIn the near future, Poland is going to have more and more favorable conditions for viticulture. Organic acids and polyphenols are among the most commonly analyzed compounds due to their beneficial properties for human health and their importance in the winemaking process. In this work, a new technique involving ultrasound-assisted solvent extraction of porous membrane-packed liquid samples (UASE-PMLS) was for the first time described...
-
Dispersive liquid-liquid microextraction combined with gas chromatography–mass spectrometry for in situ determination of biogenic amines in meat: Estimation of meat's freshness
PublikacjaA dispersive liquid-liquid microextraction (DLLME) gas chromatography–mass spectrometry (GC–MS) technique was developed for the determination of selected biogenic amines (BAs) in samples of poultry, pork and beef. Prior to the extraction process, an appropriate volume of sodium hydroxide solution was added to each of the portioned samples. Next, samples were homogenized, centrifuged and finally sonicated at an increased temperature....
-
Lateral forces determine dimensional accuracy of the narrow‑kerf sawing of wood
PublikacjaThe shrinking global forest area limits the supply of industrially usable raw resources. This, in combination with the ever‑increasing consumption of timber due to population growth can lead to the lack of a positive balance between the annual volumetric growth and consumption of wood. An important innovation toward increasing environmental and economic sustainability of timber production is to reduce the volume of wood residues...