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Search results for: PROCESS MODELLING
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Synchronous generator model taking into account the non-uniform saturation of the pole shoes
PublicationFor the evaluation of modern electric power systems with regard to their behavior, weight, and reliability a novel modeling and simulation tools have been developed. The paper presents circuit model of synchronous generator taking into account both the non-sinusoidal distribution of the stator and rotor winding, and non-uniform saturation of the pole shoes. This model is suitable for simulation of both salient and no-salient pole...
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Improved model of isothermal and incompressible fluid flow in pipelines versus the Darcy–Weisbach equation and the issue of friction factor
PublicationIn this article, we consider the modelling of stationary incompressible and isothermal one-dimensional fluid flow through a long pipeline. The approximation of the average pressure in the developed model by the arithmetic mean of inlet and outlet pressures leads to the known empirical Darcy–Weisbach equation. Most importantly, we also present another improved approach that is more accurate because the average pressure is estimated...
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Advanced Lithium-Ion Battery Model for Power System Performance Analysis
PublicationThe paper describes a novel approach in battery storage system modelling. Different types of lithium-ion batteries exhibit differences in performance due to the battery anode and cathode materials being the determining factors in the storage system performance. Because of this, the influence of model parameters on the model accuracy can be different for different battery types. These models are used in battery management system...
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Simplified approach to assess the dynamic response of a container ship subjected to bow slamming load
PublicationSimplified approach to assess the dynamic response of a container ship subjected to the bow slamming load, resulting in a transient vibratory response, typically called a 'whip-ping', is presented. The accurate numerical modelling is very complex and involves cou-pling of the hydrodynamic and structural solution at every time step, leading to huge com-putational and workload cost. Thus, the one-way coupling methodology is adopted,...
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What matters most to patients? On the Core Determinants of Patient Experience from Free Text Feedback
PublicationFree-text feedback from patients is increasingly used for improving the quality of healthcare services and systems. A major reason for the growing interest in harnessing free-text feedback is the belief that it provides richer information about what patients want and care about. The use of computational approaches such as structural topic modelling for analysing large unstructured textual data such as free-text feedback from patients...
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A Reduction Method for Bathymetric Datasets that Preserves True Coastal Water Geodata
PublicationWater areas occupy over 70 percent of the Earth’s surface and are constantly subject to research and analysis. Often, hydrographic remote sensors are used for such research, which allow for the collection of information on the shape of the water area bottom and the objects located on it. Information about the quality and reliability of the depth data is important, especially during coastal modelling. In-shore areas are liable...
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Cable-stayed cantilever structures as an expat of unique application in the construction of a building located in seismic area – an author’s project of multifunctional building in Lisbon, Portugal
PublicationThe article presents numerical simulations for the modelling of seismic impact on the structure of unique cantilever cablestayed structure with application of two methods. The Response Spectrum method, in which a spectrum of the structure's responses to an earthquake's impact is generated and the Accelerogram method, in which we generate dynamic load in the form of a diagram of the connection between acceleration and time for...
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NON-LINEAR MASTIC CHARACTERISTICS BASED ON THE MODIFIED MSCR (MULTIPLE STRESS CREEP RECOVERY) TEST
PublicationMastic containing asphalt in its composition is an example of a viscoelastic material. It is an effective binder in asphalt. It consists of a filler (<0.063 mm) and asphalt mixed in the right proportions. Just like in asphalt, its response depends on the temperature level, the load and stress time. Changing the stress stiffness of the mastic affects the non-linear course of the stress-strain relationship. Modelling of the non-linear...
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Assessing groundwater vulnerability to pollution in the Puck region (denudation moraine upland) using vertical seepage method
PublicationDegradation of groundwater quality can cause a serious water supply and environmental problems. The identify of potential groundwater pollution can be determined by assessment of groundwater vulnerability method. The assessment of groundwater vulnerability to pollution was based on estimation of migration time of potential conservative contamination through the vadose zone. Area of investigation is a type of denudation moraine...
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CONTROL OF THE WAVES IN A TOWING TANK WITH THE USE OF A BLACK-BOX MODEL
PublicationThe paper describes an adaptive control system of the waves, implemented in the Ship Design and Research Centre, CTO S.A. The purpose of generating the waves in the towing tank is the modelling of the environmental conditions during hydrodynamic model tests. The tests are performed on scale models of towed or free running ships, anchored structures like oil rigs or bottommounted structures, e.g. wind turbines. In the towing tank...
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Photogrammetric and total station's measurement of compressed column's model
PublicationModelling studies continue to play an important role. One of such study is stress determination in the reinforcement bars of reinforced columns and determine column's axis deformation. The article presents measurements results of control points located on the model of reinforced concrete column. The column was compressed in few series till it's destruction. In this studies, photogrammetric method and total station measurements...
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PROPELLER INVESTIGATIONS BY MEANS OF NUMERICAL SIMULATION
PublicationThe analyses of hydroacoustics are of high interest at the moment due to strong impact of hydroacoustic phenomena on marine environment; the noises, generated e.g. by marine traffic, may be harmful for sea life. The analyses presented here are focused on one of main sources of noises generated by ships, i.e. cavitating propeller. The goal of the work is the assessment of the cavitation phenomenon, carried out with the standard...
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Multi-nodal PWR reactor model — Methodology proposition for power distribution coefficients calculation
PublicationIn the paper the multi-nodal Pressurized Water Reactor (PWR) model called Mann’s model is presented. This models is used for modelling purposes of the heat transfer from fuel to coolant in reactor core. The authors expand widely used in literature approach by defining additional coefficients for the heat transfer model. These parameters approximate the power generation distribution in the PWR reactor core according to the to the...
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Editorial for the special issue on advances in forward and inverse surrogate modeling for high-frequency design
PublicationThe design of modern‐day high‐frequency devices and circuits, including microwave/RF, antenna and photonic components, historically has relied on full‐wave electromagnetic (EM) simulation tools. Initially used for design verification, EM simulations are nowadays used in the design process itself, for example, for finding optimum values of geometry and/or material parameters of the structures of interest. In a growing number of...
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Backscattering properties of southern Baltic herring
PublicationReliable TS(L) relationship is required to improve acoustic algorithms of abundanceestimation of Baltic herring. The relationships, empirically obtained in different parts of theBaltic Sea, produce up to 8 dB – difference in the herring TS. In order to develop an accurateTS(L) relationship, it is important to analyze factors controlling the TS variability. Thepossible impact of the regional difference...
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Half-Order Modeling of Saturated Synchronous Machine
PublicationNoninteger order systems are used to model diffusion in conductive parts of electrical machines as they lead to more compact and knowledge models but also to improve their precision. In this paper a linear half-order impedance model of a ferromagnetic sheet deduced from the diffusion of magnetic field is briefly introduced. Then, from physical considerations and finite elements simulation, the nonlinear half-order impedance model...
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Grand Challenges on the Theory of Modeling and Simulation
PublicationModeling & Simulation (M&S) is used in many different fields and has made many significant contributions. As a field in its own right, there have been many advances in methodologies and technologies. In 2002 a workshop was held in Dagstuhl, Germany, to reflect on the grand challenges facing M&S. Ten years on, a series of M& S Grand Challenge activities are marking a decade of progress and are providing an opportunity to reflect...
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Abstract class method use on common characteristics of UE regions for better road safety management in these regions.
PublicationRoad Safety is the significant problem requiring still a lot of attention. Despite lots of actions for road fatalities reduction, in many countries or regions situation doesn't improve as good as in the other cases. Even if these actions are very similar. It is so difficult issue, that the answer why is that happens hasn't been found yet. In this paper authors focused on the road network of European regions, classified as NUTS...
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Impact of the Manufacturing Sector on the Export Competitiveness of European Countries – a Spatial Panel Analysis
PublicationThe purpose of this paper is to determine how changes in the export competitiveness of the EU economy (measured by exports and net exports) depend on changes in the competitiveness of processing industries, on the basis of manufacturing data from 19 EU countries over years 1995-2009 and using a spatial panel data model. The determinants of export competitiveness are selected in the light of predictions from international trade...
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Modal analysis of a steel grandstand
PublicationAmong the issues related to the idea of sustainable society is the safety of civil engineering structures devoted to satisfy different needs of people. One of the types of structures devoted to satisfy recreational needs are grandstands, which are used during sport events or music concerts. It is obligatory to consider interaction between structure and crowd load especially when the crowd movement involves rhythmic jumping, dancing,...
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Harnessing digital technologies for poverty reduction. Evidence for low-income and lower-middle income countries
PublicationThis paper contributes to understanding the relationship between ICT deployment and poverty alleviation in developing countries. It assess the digital technologies contribution to poverty reduction, through different channels of impact, like education, labor market, income and ICTtrade related activities. Using the sample of 40 developing countries between 1990 and 2019, it relies on macro data extracted from the World Bank Development...
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A numerical analysis of the thermal effects in the jet impingement stagnation zone
PublicationMost of the flows occurring in the engineering systems are turbulent and their accurate numerical analysis is still challenging, especially when combined with the heat transfer. One of the methods of heat transfer enhancement is utilization of the turbulent impinging jets, which were recently applied also in the heat exchangers. Their positive impact on the heat transfer performance was proven, but many questions related to its...
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The role of traditional architectural models in the first stages of education.
PublicationThe oldest architectural models discovered by scientists date from the Middle Ages, while models or 1:1 scale prototypes were used in ancient times. Architectural miniatures quickly evolved into an indispensable tool for designers that enabled them to creatively express their thoughts and ideas. Mock-ups became a way of helping a designer communicate a concept, and their educational value was also recognised. The method of modelling,...
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A probabilistic-driven framework for enhanced corrosion estimation of ship structural components
PublicationThe work proposes a probabilistic-driven framework for enhanced corrosion estimation of ship structural components using Bayesian inference and limited measurement data. The new approach for modelling measurement uncertainty is proposed based on the results of previous corrosion tests that incorporate the non-uniform character of the corroded surface of structural components. The proposed framework's basic features are outlined,...
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Virtual tour as an innovative tool for architectural education - from understanding heritage to creativity stimulation
PublicationThe article presents the potential of the virtual tour in architectural education as an innovative tool to better understand heritage and stimulate creativity. A methodology for creating a virtual tour based on a point cloud obtained from a survey based on 360° camera images is presented. Two different purposes for the use of point clouds are presented from reliable indicators of heritage documentation useful for digital twin modelling...
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Optimisation of cooperation of hybrid renewable energy sources with hydrogen energy storage toward the lowest net present cost
PublicationThe paper presents the results of a technical and economic analysis of the power supply for a model industrial facility based on intermittent renewable energy sources in the form of wind turbines and photovoltaic modules, supplemented with hydrogen energy storage. The adopted power supply strategy assumed the maximisation of self-consumption of self-produced electricity. Six variants were considered, including two with an energy...
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Analytical Traffic Model for a Multidomain IMS/NGN Network Including Service and Transport Stratum
PublicationThis paper addresses the problem of modelling call processing performance (CPP) in a multidomain Next Generation Network (NGN) architecture including the elements of the IP Multimedia Subsystem (IMS) in service stratum and based on the Multiprotocol Label Switching (MPLS) technology in transport stratum. An analytical traffic model for such an architecture is proposed by integrating the formerly implemented submodels of service...
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The interaction of the pulsed laser irradiation with titania nanotubes - Theoretical studies on the thermal effect
PublicationThis paper reports temperature dispersion simulations of titania nanotubes irradiated by the 355 nm, pulsed, nanosecond laser. The modelling with the use of Finite Elements Method concerns titania nanotubes of the length and the wall thickness in the range of 0.5–2 μm and 5–20 nm, respectively. The uniqueness of the morphology was preserved by ensuring the wall thickness variation along the height of the tube, which was determined...
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Adaptive Method for Modeling of Temporal Dependencies between Fields of Vision in Multi-Camera Surveillance Systems
PublicationA method of modeling the time of object transition between given pairs of cameras based on the Gaussian Mixture Model (GMM) is proposed in this article. Temporal dependencies modeling is a part of object re-identification based on the multi-camera experimental framework. The previously utilized Expectation-Maximization (EM) approach, requiring setting the number of mixtures arbitrarily as an input parameter, was extended with the...
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The effects of perceived risk, brand value, and brand trust on eWOM
PublicationUnrestricted access to the Internet, mobile devices, social applications and offering shopping comment options via online stores and platforms, encourages customers to generate online reviews about brands. That is why it became important to learn about the factors that motivate customers to create electronic word of mouth (eWOM). The survey aimed to check if there are links between perceived brand value, perceived risk, brand trust...
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Impact of the Artificial Strait in the Vistula Spit on the Hydrodynamics of the Vistula Lagoon (Baltic Sea)
PublicationIn the Vistula Lagoon, storm surges are induced by variable sea levels in the Gulf of Gdańsk and wind action. The rising of the water level in the southern part of the basin, exceeding 1.0 m above mean sea level, can be dangerous for the lowland area of Żuławy Elbląskie, causing the inundation of the polders adjacent to the lagoon. One of the potential possibilities to limit the flood risk is to decrease the water level in the...
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Numerical analysis of mechanical properties of an infill structure used in 3D printings
PublicationThe paper presents results of a numerical analysis focused on an identification of mechanical properties of an element created by using Fused Deposition Modelling additive manufacturing technique (FDM). There is presented a description of technology of the 3D printing, numerical model created by using the finite element method (FEM), as well as some problems referred to estimation of the mechanical properties of the printout. The...
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Local buckling of composite channel columns
PublicationThe investigation concerns local buckling of compressed flanges of axially compressed composite channel columns. Cooperation of the member flange and web is taken into account here. The buckling mode of the member flange is defined by rotation angle a flange about the line of its connection with the web. The channel column under investigation is made of unidirectional fibre-reinforced laminate. Two approaches to member orthotropic...
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MARSTRUCT benchmark study on nonlinear FE simulation of an experiment of an indenter impact with a ship side-shell structure
PublicationThis paper presents a benchmark study on collision simulations that was initiated by the MARSTRUCT Virtual Institute. The objective was to compare assumptions, finite element models, modelling techniques and experiences between established researchers within the field. Fifteen research groups world-wide participated in the study. An experiment involving a rigid indenter penetrating a ship-like side structure was used as the case...
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Rhamnolipid CMC Prediction
PublicationRelationships between the purity, pH, hydrophobicity (log Kow) of the carbon substrate, and the critical micelle concentration (CMC) of rhamnolipid type biosurfactants (RL) were investigated using a quantitative structure–property relationship (QSPR) approach and are presented here for the first time. Measured and literature CMC values of 97 RLs, representing biosurfactants at different stages of purification, were considered....
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Pounding between Inelastic Three-Storey Buildings under Seismic Excitations
PublicationStructural interactions between adjacent, insufficiently separated buildings have been repeatedly observed during damaging ground motions. This phenomenon, known as the structural pounding, may result in substantial damage or even total collapse of structures. The aim of the present paper is to show the results of the nonlinear numerical analysis focused on pounding between inelastic three-storey buildings under seismic excitations....
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Vehicular Communication Environments
PublicationCommunication to and between road vehicles (cars, truck, buses, trains, etc.) are of growing interest. This is partly due to the attractive services that cooperative intelligent transport systems (C-ITSs) provides, mainly in the areas of traffic safety and traffic efficiency. An enabler for C-ITS is wireless vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication, collectively referred to as vehicle-to-X (V2X)...
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Simulations of hydro-fracking in rock mass at meso-scale using fully coupled DEM/CFD approach
PublicationThe paper deals with two-dimensional (2D) numerical modelling of hydro-fracking (hydraulic fracturing) in rocks at the meso-scale. A numerical model was developed to characterize the properties of fluid-driven fractures in rocks by combining the discrete element method (DEM) with computational fluid dynamics (CFD). The mechanical behaviour of the rock matrix was simulated with DEM and the behaviour of the fracturing fluid flow...
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The Weibull model of the multipath fading channel
Open Research DataThe dataset contains the results of simulations that are part of the research on modelling the multipath fading in the communication channel. The Weibull fading envelope is generated using the Monte-Carlo simulation (MCS) in the LabVIEW programming environment.
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The Suzuki model of the multipath fading channel
Open Research DataThe dataset contains the results of simulations that are part of the research on modelling the multipath fading in the communication channel. The Suzuki fading envelope is generated using the Monte-Carlo simulation (MCS) in the LabVIEW programming environment.
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Advanced Modeling of Management Processes in Information Technology
PublicationThis book deals with the issues of modeling management processes of information technology and IT projects while its core is the model of information technology management and its component models (contextual, local) describing initial processing and the maturity capsule as well as a decision-making system represented by a multi-level sequential model of IT technology selection, which acquires a fuzzy rule-based implementation...
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Evolutionary Sets of Cooperating Ship Trajectories: COLREGS Compliance
PublicationThe paper presents a newly designed improvement to the method of solving multi-ship encounter situations. In general, the method combines some of the assumptions of game theory with evolutionary programming and aims to find optimal set of cooperating trajectories of all ships involved in an encounter situation. The improvement presented here is a new way of modelling some of the COLREGS rules. Due to this change, the method is...
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Actual and reference evapotranspiration for a natural, temperate zone fen wetland – Upper Biebrza case study
PublicationEvapotranspiration is the key and predominant component of the water balance in wetlands. Direct evapotranspiration measurements are challenging in wetlands due to their remoteness and high surface water level. This article describes the actual (ETa and reference evapotranspiration (ET0) from a cultivated wet meadow located in the Biebrza National Park – the largest national park in north-east Poland, Central Europe. The data were...
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Current Source Inverter Fed Drive
PublicationThis book covers three-phase and multiphase (more than three-phase) motor drives including their control and practical problems faced in the field (e.g., adding LC filters in the output of a feeding converter), are considered. The new edition contains links to Matlab®/Simulink models and PowerPoint slides ideal for teaching and understanding the material contained within the book. Readers will also benefit from the inclusion of: A...
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Evaluation of the Influence of Farming Practices and Land Use on Groundwater Resources in a Coastal Multi-Aquifer System in Puck Region (Northern Poland)
PublicationThis study focuses on the modeling of groundwater flow and nitrate transport in a multi-aquifer hydrosystem in northern Poland, adjacent to Puck Bay (Baltic sea). The main goal was to investigate how changes in land use and farming practices may affect groundwater recharge and submarine groundwater discharge (SGD) to the sea and the associated N-NO3 fluxes. An integrated modelling approach has been developed, which couples the...
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Which Curve Fits Best: Fitting ROC Curve Models to Empirical Credit-Scoring Data
PublicationIn the practice of credit-risk management, the models for receiver operating characteristic (ROC) curves are helpful in describing the shape of an ROC curve, estimating the discriminatory power of a scorecard, and generating ROC curves without underlying data. The primary purpose of this study is to review the ROC curve models proposed in the literature, primarily in biostatistics, and to fit them to actual credit-scoring ROC data...
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Materials Design for the Titanium Scaffold Based Implant
PublicationThe main objective of here presented research is a design the scaffold/porous titanium(Ti) alloy based composite material demonstrating better biocompatibility, longer lifetime andbioactivity behaviour for load-bearing implants. The development of such material is proposed bymaking a number of consecutive tasks. Modelling the mechanical, biomechanical and biologicalbehavior of porous titanium structure and an elaboration of results...
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In silico assessment and sonochemical synthesis of 2-alkynyl 3-chloropyrazines as prospective ligands for SARS-CoV-2
PublicationThe recent global pandemic caused by COVID-19 has triggered an intense effort worldwide towards the development of an effective cure for this disease. In our effort we have explored the 2-alkynyl substituted 3-chloropyrazine framework as a potential template for the design of molecules for this purpose. Our strategy was supported by the in silico studies of representative compounds to assess their binding affinities via docking...
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Identification of synergistic and antagonistic actions of environmental pollutants: Bisphenols A, S and F in the presence of DEP, DBP, BADGE and BADGE·2HCl in three component mixtures
PublicationEcosystems are facing increased pressure due to the emission of many classes of emerging contaminants. However, very little is known about the interactions of these pollutants, such as bisphenols (BPs), plasticizers or pharmaceuticals. By employing bioluminescent bacteria (Microtox assay), we were able to define interactions between selected emerging pollutants (namely BPA, BPS, BPF, BADGE, BADGE·2HCl, DEP, DBP) in ternary mixtures, at...
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Bicycle Traffic Model for Sustainable Urban Mobility Planning
PublicationModelling tools and transport models are required to assess the impact of measures for the effective planning of cycling routes in cities. This paper presents the methodology for developing a four-stage macroscopic model of bicycle traffic for the city of Gdynia, and its use in planning new bicycle routes, considering a modal shift. The model presented in this paper allows for the evaluation of the influence of the characteristics...