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Heteroleptic tri-tert-butoxysilanethiolate complexes of manganese(II) - thermal studies
PublicationThe thermal behavior of Mn(II) silanethiolate series [Mn(SR)2L(MeOH)n], where R=SSi(OBut)3, L=heterocyclic nitrogen base and n=0, 1 or 2 has been comparatively investigated using differential scanning calorimetry (DSC), thermogravimetry (TG) and TG-infrared spectoscopy (IR) techniques. The TG curves indicate the differences in the thermal decomposition due to presence of distinct N-donor ligands and labile MeOH molecules coordinated...
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Measurement of benzene concentration in urban air using passive sampling
PublicationAbstract The concentration of benzene in urban air in theTri-City area of Poland (Gdańsk-Sopot-Gdynia, andTczew) was assessed using diffusive passive samplers (Rad-iello). Samples were collected during a four-year monitoringcampaign (2007-2010) at selected monitoring stations man-aged by the Agency of Regional Air Quality Monitoring inthe Gdańsk Metropolitan Area (ARMAAG) Foundation.The performance of the passive samplers was investigatedin...
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Detection and localization of selected acoustic events in acoustic field for smart surveillance applications
PublicationA method for automatic determination of position of chosen sound events such as speech signals and impulse sounds in 3-dimensional space is presented. The evens are localized in the presence of sound reflections employing acoustic vector sensors. Human voice and impulsive sounds are detected using adaptive detectors based on modified peak-valley difference (PVD) parameter and sound pressure level. Localization based on signals...
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Detection and localization of selected acoustic events in 3D acoustic field for smart surveillance applications
PublicationA method for automatic determination of position of chosen sound events such as speech signals and impulse sounds in 3-dimensional space is presented. The events are localized in the presence of sound reflections employing acoustic vector sensors. Human voice and impulsive sounds are detected using adaptive detectors based on modified peak-valley difference (PVD) parameter and sound pressure level. Localization based on signals...
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Pursuing Listeners’ Perceptual Response in Audio-Visual Interactions - Headphones vs Loudspeakers: A Case Study
PublicationThis study investigates listeners’ perceptual responses in audio-visual interactions concerning binaural spatial audio. Audio stimuli are coupled with or without visual cues to the listeners. The subjective test participants are tasked to indicate the direction of the incoming sound while listening to the audio stimulus via loudspeakers or headphones with the head-related transfer function (HRTF) plugin. First, the methodology...
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Highly sensitive large strain cellulose/multiwalled carbon nanotubes (MWCNTs)/thermoplastic polyurethane (TPU) nanocomposite foams: From design to performance evaluation
PublicationAerogel-based polymer composite foams are promising for large strain piezoresistive sensors, but their aerogel skeleton is partially destroyed during the foaming process, limiting their sensitivity. Herein, the thermoplastic polyurethane was synthesized on the aerogel skeleton to obtain cellulose/multiwalled carbon nanotubes (MWCNTs)/thermoplastic polyurethane (TPU) nanocomposite materials foamed with the aid of supercritical carbon...
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Pulsed UV-irradiated Graphene Sensors for Ethanol Detection at Room Temperature
PublicationA graphene-based gas sensor fabricated in a FET (GFET) configuration and its sensitivity towards ethanol and methane is reported. Detection of ethanol at the level of 100 ppm was observed under pulsed UV irradiation and after cleaning by UV light in the N2 ambient. Reduction of the frequency of UV irradiation pulses resulted in increased changes in sensor resistance in the presence of ethanol. Improved sensing behavior was ascribed...
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Three-Dimensional Printing of Bone Models
PublicationThe trabecular bone occurs, for example, in the femoral heads. Understanding the phenomenon of bone tissue degeneration can be the basis for the possibility of looking for alternative methods of surgical treatment of bone loss. The paper presents the results of the trabecular bone model, which was produced in additive manufacturing method with fused filament fabrication technology. The verification of the mechanical behavior of...
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Alternative Approach to Convolution Term of Viscoelasticity in Equations of Unsteady Pipe Flow
PublicationIn the paper the selected aspects concerning description of viscoelastic behavior of pipe walls during unsteady flow are analyzed. The alternative convolution expression of the viscoelastic term is presented and compared with the corresponding term referring to unsteady friction. Both approaches indicate similarities in the forms of impulse response functions and the parameter properties. The flow memory was introduced into convolution...
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Influence of electropolymerization conditions on the morphological and electrical properties of PEDOT film
PublicationIn this work the effects of electropolymerization conditions on the morphological properties and conductivity of poly(3,4-ethylenedioxythiophene) (PEDOT) film have been studied. PEDOT films were electrochemically synthesized in a one step process from acetonitrile solution containing 3,4-ethylenedioxythiophene (EDOT) and lithium perchlorate. Based on atomic force microscopy, scanning electron microscopy, cyclic voltammetry and...
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Chemical structure, thermal and mechanical characterization of bio-based polyurethane composites filled with microcrystalline cellulose
PublicationOver the past several decades, the interest in replacing the synthetic components used in the production of polymers and composites with their natural counteparts has been growing. Biocomposites belong to the group of materials produced with the use of renewable raw materials. There has been a recent surge of interest in the industrial applications of composites containing natural fibres reinforced with biopolymers. Biopolymers...
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Znaczenie płci w procesie zakupu marek własnych sieci handlowych – analiza wielogrupowa
PublicationThe purpose of the article is to analyze the differences in the behavior of men and women in the process of purchasing store brands (SBs). Using an established conceptual model, we intended to identify differences, depending on gender of buyers, in the size of the effects of store image and brand price-image on perceived risk and subsequently on store brand purchase intention. A total of 652 respondents participated in the study....
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AUTOMATIC LEARNING OF STRATEGY AND RULES IN CARD GAMES USING IMAGE FROM CAMERA
PublicationBelow work tries to answer a question: if it is possible to replace real human with computer system in social games. As a subject for experiments, card games were chosen, because they require a lot of player interaction (playing and taking cards), while their rules are easy to present in form of clear list of statements. Such a system, should allow real players to play without constant worrying about guiding or helping computer...
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Modeling bioaugmentation with nitrifiers in membrane bioreactors
PublicationBioaugmentation with nitrifiers was studied using two pilot-scale membrane bioreactors, with the purpose of assessing the suitability of state-of-the-art activated sludge models (ASMs) in predicting the efficiency of bioaugmentation as a function of operating conditions. It was demonstrated that the temperature difference between seeding and seeded reactors (ΔT) affects bioaugmentation efficiency. Experimental data were accurately...
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Badanie wpływu ruchu niższego priorytetu na jakość usług o wymaganiach czasu rzeczywistego w sieci IP QoS.
PublicationW artykule przedstawiono wyniki badań dotyczące wpływu rozkładu długości pakietów ruchu o niższym priorytecie na jakość usług o wymaganiach czasu rzeczywistego (real time services), korzystających ze schematu obsługi Expedited Forwarding Per Hop Behavior (EF PHB) w sieci IP QoS Differentiated Services (DiffServ). Wyniki zaprezentowane w referacie zostały uzyskane zarówno przy pomocy modeli analitycznych, opisujących gwarancje statystyczne...
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Diffusion equations with spatially dependent coefficients and fractal Cauer-type networks
PublicationIn this article, we formulate and solve the representation problem for diffusion equations: giving a discretization of the Laplace transform of a diffusion equation under a space discretization over a space scale determined by an increment h > 0, can we construct a continuous in h family of Cauer ladder networks whose constitutive equations match for all h > 0 the discretization. It is proved that for a finite differences discretization...
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Dynamic impedance measurements of the Direct Methanol Fuel Cell cathode at various operating temperatures
PublicationThis article discusses the application of impedance analysis for diagnosing the cathode of a direct methanol fuel cell at various operating temperatures. The Dynamic Electrochemical Impedance Spectroscopy technique coupled with a linear current scan was applied for this purpose. This technique allowed the observation of changes in the cathode's properties in the fuel cell operating under real working conditions. An equivalent model...
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Accurate Post-processing of Spatially-Separated Antenna Measurements Realized in Non-Anechoic Environments
PublicationAntenna far-field performance is normally evaluated in expensive laboratories that maintain strict control over the propagation environment. Alternatively, the responses can be measured in non-anechoic conditions and then refined to extract the information on the structure field-related behavior. Here, a framework for correction of antenna measurements performed in non-anechoic test site has been proposed. The method involves automatic...
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Virtual immersive environments
PublicationYet a higher level of active systems may be achieved when users are fully immersed in an interface which is a 3D computer generated virtual world and can interact with surrounding objects of that world as they were in a real one. This is the issue covered by Chapter 7. Interaction in such a world is both multidimensional and multimodal, with the possibility of free movement of the user in any direction and the simultaneous stimulation...
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A Simple Replica Method as the Way to Obtain a Morphologically and Mechanically Bone-like Iron-Based Biodegradable Material
PublicationPorous iron-based scaffolds were prepared by the simple replica method using polyurethane foam as a template and applying the sintering process in a tube furnace. Their surface morphology was characterized using scanning electron microscopy (SEM) and phase homogeneity was confirmed using X-ray diffraction (XRD). Corrosion behavior was determined using immersion and potentiodynamic polarization methods in phosphate buffered saline...
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Does the Use of Cell Phones and Headphones at the Signalised Pedestrian Crossings Increase the Risk of Accident?
PublicationReduction of the number of fatalities among pedestrians remains a topical issue in Poland. For many years, this percentage has remained at around 30% of all those who were killed on the road. At the same time, there is an increase in the use of electronic devices by pedestrians and cyclists that may affect their perception when crossing the road. This can lead to traffic accidents. In order to investigate the problem, field studies...
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Effects of Road Infrastructure on Pedestrian Safety
PublicationThe objective of the work was to identify risks for pedestrians that involve road infrastructure and roadside and to define how selected elements of geometry and traffic layout affect driver behaviour (speed on approaching pedestrian crossings). The results have helped to formulate recommendations on pedestrian crossing design. The research included an analysis of 2013-2017 statistics to identify the...
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Surface diffusion and cluster formation of gold on the silicon (111)
PublicationPurpose: Investigation of the gold atoms behaviour on the surface of silicon by molecular dynamics simulation method. The studies were performed for the case of one, two and four atoms, as well as incomplete and complete filling of gold atoms on the silicon surface. Design/methodology/approach: Investigations were performed by the method of molecular dynamics simulation using the Large-scale Atomic/Molecular Massively Parallel...
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Nitrogen-incorporated boron-doped diamond films for enhanced electrochemical supercapacitor performance
PublicationThe electrochemical (EC) supercapacitor, known for its rapid charging, reliability, and versatile applications, demands optimized electrode characteristics and an understanding of their electrochemical behaviour. Although boron-doped diamond (BDD) holds promise as a supercapacitor electrode, a crucial gap exists in comprehending its material behaviour under specific growth conditions. Here, nitrogen-incorporated BDD (N-BDD) films...
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Tailoring the electrochemical degradation of iron protected with polypyrrole films for biodegradable cardiovascular stents
PublicationThe degradation of polypyrrole (PPy) coated iron is studied in phosphate buffer saline solution at 37 °C by odd random phase multisine electrochemical impedance spectroscopy (ORP-EIS). PPy is electropolymerized with anti-inflammatory salicylates incorporated in the film, as a drug release system. The modelling of EIS over time provides the quantitative description of the corrosion behaviour of the material. Thus, the reliable...
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On the material symmetry group for micromorphic media with applications to granular materials
PublicationWithin the framework of the theory of nonlinear elastic micromorphic continua we introduce the new definition of the local material symmetry group. The group consists of ordered triples of second- and third-order tensors describing such changes of a reference placement that cannot be recognized with any experiment. Using the definition we characterize the micromorphic isotropic media, micromorphic fluids, solids and special intermediate...
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The preferable ways of decision-making in IT teams
PublicationSoftware development team collaboration requires various decisions regarding essential aspects of a project’s progress. General and particular decision-making models are considered, and their main aspects such as team types, problem solving categories, and decision-making ways are analyzed. The research concerns representative groups of IT specialists and their preferences in decision-making are investigated. Four possible cases were...
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Tripping limitations of residual current devices in photovoltaic installations
PublicationIn electrical installations with photovoltaic sources of energy, earth fault current may comprise alternating current component and direct current component. The waveform shape of this earth fault current mainly depends on the point of the fault and the properties of a photovoltaic power electronics converter. The waveform shape of the current influences operation of protection devices, especially tripping threshold of residual...
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A comprehensive approach to double inverted pendulum modelling
PublicationThe problem of mathematical modelling and indication of properties of a DIP has been investigated in this paper. The aim of this work is to aggregate the knowledge on a DIP modelling using the Euler-Lagrange formalism in the presence of external forces and friction. To indicate the main properties important for simulation, model parameters identification and control system synthesis, analytical and numerical tools have been used....
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Comparison of Selection Schemes in Evolutionary Method of Path Planning
PublicationThis article compares an impact of using various selection schemes on the quality of the solution for the problem of planning the path for a moving object using the evolutionary method. In study case problem of avoiding collisions at sea is analyzed. The modelled environment includes static constraints (lands, canals, etc.) and dynamic objects (moving ships). Article analyses behaviour of selection schemes in two similar environments...
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Critical Case Stochastic Phylogenetic Tree Model via the Laplace Transform
PublicationBirth–and–death models are now a common mathematical tool to describe branching patterns observed in real–world phylogenetic trees. Liggett and Schinazi (2009) is one such example. The authors propose a simple birth–and–death model that is compatible with phylogenetic trees of both influenza and HIV, depending on the birth rate parameter. An interesting special case of this model is the critical case where the birth rate equals the...
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Reliability And Safety As An Objective Of Intelligent Transport Systems In Urban Areas
PublicationTechnologies that use transport telematics offer tools for strengthening urban transport systems. They rationalise the use of the existing infrastructure and transport management systems, increase their reliability and safety and improve the transport behaviour of residents, while reducing the operating costs of transport. The main reason for using Intelligent Transport Systems (ITS) is the need to implement measures to reduce...
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Alternative Modeling of Volunteer Based Systems
PublicationThe canonical approach to model a flow of a voluntary based computing, as presented in Chapter 7 may tax the capacity of the simulator, especially when a more complex model of Voluntary Computing, proposed in [1], is used which would imply that, for typical heterogeneous groups of volunteers, several thousands of threads would have to be run inside the simulator, to mimic closely the behaviour of every volunteer. This chapter presents...
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Evolutionary Ship Track Planning within Traffic Separation Schemes – Evaluation of Individuals
PublicationThe paper presents an extended version of the author’s Evolutionary Sets of Safe Ship Trajectories method. The method plans safe tracks of all ships involved in an encounter including speed reduction manoeuvres, if necessary, and taking into account Rule 10 of COLREGS, which specifies ships’ behaviour within Traffic Separation Schemes governed by IMO. The paper focuses on the evaluation phase of the evolutionary process and shows...
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Analysis of Interspike-Intervals for the General Class of Integrate-and-Fire Models with Periodic Drive
PublicationWe study one-dimensional integrate-and-fire models of the general type x˙=F (t, x) and analyze properties of the firing map which iterations recover consecutive spike timings. We impose very week constraints for the regularity of the function F (t, x), e.g. often it suffices to assume that F is continuous. If additionally F is periodic in t, using mathematical study of the displacement sequence of an orientation preserving circle...
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Numerical investigations on early indicators of fracture in concrete at meso-scale.
PublicationFracture is a major reason of the global failure of concretes. The understanding of fracture is important to ensure the safety of structures and to optimize the material behaviour. In particular an early prediction possibility of fracture in concretes is of major importance. In this paper, concrete fracture under bending was numerically analysed using the Discrete Element Method (DEM). The real mesoscopic structure of a concrete...
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Buckling analyses of cylindrical metal silos containing bulk solids
PublicationThe paper presents quasi-static 3D buckling analysis results of thin-walled cylindrical metal silos with and without bulk solids. The behaviour of the bulk solid was described with a hypoplastic constitutive model. Non-linear analyses with geometric and material non-linearity were performed with a perfect and an imperfect silo shell. Different initial geometric imperfections were considered. The influence of internally stored bulk...
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Models of Structures in Didactics
PublicationThe final aim of teaching students subjects, such as structural mechanics, reinforced concrete, and steel structures is to teach them how structures work in a given building as well as to provide them with skills enabling them to calculate and design structures. The behavioral model of the structure, contrary to the architectural model, which focuses mainly on the external form of the building, shows workings from both the static...
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Intracranial electrophysiological recordings from the human brain during memory tasks with pupillometry
PublicationData comprise intracranial EEG (iEEG) brain activity represented by stereo EEG (sEEG) signals, recorded from over 100 electrode channels implanted in any one patient across various brain regions. The iEEG signals were recorded in epilepsy patients (N=10) undergoing invasive monitoring and localization of seizures when they were performing a battery of four memory tasks lasting approx. 1 hour in total. Gaze tracking on the task...
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Self-organized multilayered graphene-boron doped diamond hybrid nanowalls for high performance electron emission devices
PublicationCarbon nanomaterials like nanotubes, nanoflakes/nanowalls and graphene have been used as electron sources due to their superior field electron emission (FEE) characteristics. Nevertheless, these materials show poor stability and a short lifetime, preventing them from being used in practical device applications. The intention of this study was to find an innovative nanomaterial, possessing both high robustness and reliable FEE behavior....
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Structural, magnetic and spectral properties of tetrahedral cobalt(II) silanethiolates: a variety of structures and manifestation of field-induced slow magnetic relaxation
PublicationBlue crystals of five heteroleptic cobalt(II) silanethiolates 1–5 have been obtained by the reaction of [Co{SSi (tBuO)3}2(NH3)]2 with aminopyridines and aminomethylpyridines at an appropriate molar ratio and their structural, spectral, thermal and magnetic properties have been established and described. All complexes 1–5 contain Co(II) ions in a tetrahedral CoN2S2 environment formed by (tBuO)3SiS− residues and pyridines and present...
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Designing acoustic scattering elements using machine learning methods
PublicationIn the process of the design and correction of room acoustic properties, it is often necessary to select the appropriate type of acoustic treatment devices and make decisions regarding their size, geometry, and location of the devices inside the room under the treatment process. The goal of this doctoral dissertation is to develop and validate a mathematical model that allows predicting the effects of the application of the scattering...
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Application and modelling of Shape-Memory Alloys for structural vibration control: State-of-the-art review
PublicationOne of the most essential components of structural design for civil engineers is to build a system that is resistant to environmental conditions such as harsh chemical environments, and catastrophic disasters like earthquakes and hurricanes. Under these circumstances and disturbances, conventional building materials such as steel and concrete may demonstrate inadequate performance in the form of corrosion, deterioration, oxidizing,...
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Alkohol-społeczny problem XXI wieku. Zastosowanie biowskaźników spożywania alkoholu w diagnostyce medycznej.
PublicationAlkohol etylowy jest legalną i ogólnodostępną substancją o działaniu psychoaktywnym. Spożywany w niewielkich ilościach może pozytywnie wpływać na zdrowie, ale jego nadmierna konsumpcja powoduje silne uzależnienie. Może być to przyczyną agresywnych zachowań, przemocy w rodzinie, problemów w kontaktach z ludźmi, problemów z prawem, samobójstw, wypadków samochodowych oraz problemów finansowych. Dlatego też, szybka i jednoznaczna diagnostyka...
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Modelling of performance of an AUV stealth vehicle. Design for operation.
PublicationIn the paper some results of research connected with modelling of performance and risk assessment of an AUV stealth vehicle are presented. A general approach to design of the stealth AUV autonomous underwater vehicle under consideration is introduced. The basic stealth characteristics of the AUV stealth vehicle are briefly described. The method of research is introduced. The AUV stealth vehicle concept is presented including the...
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Modeling of performance of an AUV stealth vehicle. Design for operation.
PublicationIn the paper some results of research connected with modelling of performance and risk assessment of an AUV stealth vehicle are presented. A general approach to design of the stealth AUV autonomous underwater vehicle under consideration is introduced. The basic stealth characteristics of the AUV stealth vehicle are briefly described. The method of research is introduced. The AUV stealth vehicle concept is presented including the...
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Toward Intelligent Recommendations Using the Neural Knowledge DNA
PublicationIn this paper we propose a novel recommendation approach using past news click data and the Neural Knowledge DNA (NK-DNA). The Neural Knowledge DNA is a novel knowledge representation method designed to support discovering, storing, reusing, improving, and sharing knowledge among machines and computing systems. We examine our approach for news recommendation tasks on the MIND benchmark dataset. By taking advantages of NK-DNA, deep...
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Shaft friction from the DMT and direct shear interface tests
PublicationThe article presents preliminary attempt to create tri-linear transfer curves for describing pile behaviour under axial loading. Transfer curves would use the parameter measured in dilatometer test, particularly a constrained modulus MDMT. The proposed method is based on concrete rough and smooth interface tests performed in a direct shear apparatus. Based on the obtained mobilization curves, relationships were created between...
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Relevance of Urban Freight Transport Modelling Towards the Challenges of Urban Freight Policy
PublicationThe main objective of this paper is to investigate how recent trends in urban freight transport analysis and modelling are related to urban freight measures set out in Gdynia’s 2016 Sustainable Urban Mobility Plan. Building on the literature a review framework was defined including 1) stakeholders, 2) descriptors, 3) objectives and 4) solution approach applied in freight modelling efforts. It was clear that the implementation...
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Ocena zastosowania wybranych reguł wymiany narzędzi w systemie produkcyjnym
PublicationIn this paper, an integrated analytical and simulation modelling framework has been developed with the objective to explore total system planning and operational issues. It enables in particular structuring the alternative process flow in manufacturing systems and their extended investigation under different tool exchange rules with limited number of tool inventory. Simulation studies performed with the proposed rules in the environment...