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Dynamic mass measurement in checkweighers using a discrete time-variant low-pass filter
PublicationConveyor belt type checkweighers are complex mechanical systems consisting of a weighing sensor (strain gauge load cell, electrodynamically compensated load cell), packages (of different shapes, made of different materials) and a transport system (motors, gears, rollers). Disturbances generated by the vibrating parts of such a system are reflected in the signal power spectra in a form of strong spectral peaks, located usually in...
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Usage of parametric echosounder with emphasis on buried object searching.
PublicationThe purpose of this article is to present the results of investigation to search for buried objects. The paper will contain echograms and other means of visualization from buried pipe placed between area of W?adys?awowo and gas platform and interesting in terms of the number of small and medium-sized unidentified objects found in the muddy bottom at different depths localized in the Gulf of Puck - results will be presented also...
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Supply current signal and artificial neural networks in the induction motor bearings diagnostics
PublicationThis paper contains research results of the diagnostics of induction motor bearings based on measurement of the supply current with usage of artificial neural networks. Bearing failure amount is greater than 40% of all engine failures, which makes their damage-free operation crucial. Tests were performed on motors with intentionally made bearings defects. Chapter 2 introduces the concept of artificial neural networks. It presents...
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Trailing-Edge Separation Control of a NACA 0015 Airfoil Using Dielectric-Barrier-Discharge Plasma Actuators
PublicationThis paper presents a part of the works conducted in the Plasmaero European project (task 3.1), where the trailing-edge flow separation of a NACA 0015 airfoil has been controlled using four different dielectric barrier discharge (DBD) actuator types at three institutions across Europe. The results show that it is possible to enhance the aerodynamic performance of aircraft at speeds up to 40 m/s. Dielectric-barrier-discharge vortex...
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Sano-Tachiya-Noolandi-Hong, Onsager and Braun models vs Monte Carlo simulation of charge photogeneration in organic solids
PublicationThe Sano-Tachiya-Noolandi-Hong (STNH), Onsager, and Braun models as well as Monte Carlo (MC) simulations of charge recombination/separation have been applied for the first time to reproduce the results of the electromodulated photoluminescence measurements in vacuum-evaporated films of fluorescent materials commonly used in optoelectronic devices. The values of the electron-hole pair final recombination speed in the monomer emitters:...
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Shape Memory Alloy-Based Fluidically Reconfigurable Metasurfaced Beam Steering Antenna
PublicationA low-cost actuator-based fluidically programmable metasurface (FPMS) antenna is proposed to solve the slow tuning speed problem of the manually fluidic based reconfigurable antennas. The FPMS-based antenna is probe-fed and comprises a 4 × 4 square ring metasurface as a superstrate. Moreover, two shape memory alloy (SMA)-based electrically-controlled actuators are employed in the design for controlling the position of the 3D-printed...
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Hybridized Space-Vector Pulsewidth Modulation for Multiphase Two-Level Voltage Source Inverter
PublicationIn space vector pulsewidth modulation (SVPWM) algorithms for multiphase two-level voltage source inverters (VSI), the components of active vectors in all orthogonal spaces have to be calculated within the processor and stored in its memory. These necessitate intensive computational efforts of the processor and large memory space. This article presents a hybridized SVPWM for multiphase two-level VSI. In this algorithm, elements...
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Galerkin Finite Element Process for Entropy Production and Thermal Evaluation of Third-Grade Fluid Flow: A Thermal Case Study
Publication: A fluid’s moving class improves its heat transmission capability, as well as its rigidity, owing to multivariate molecule suspension. In this way, nanofluids are superior to common fluids. In this study, we evaluated the features of ease and heat transfer. Furthermore, we investigated permeable media, heat source, variable heat conductivity, and warm irradiation results. A mathematical technique known as the Galerkin finite element...
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Effects of Noncontact Shoulder Tool Velocities on Friction Stir Joining of Polyamide 6 (PA6)
PublicationIn this study, the effects of the traverse and rotational velocities of the noncontact shoulder tool on the heat generation and heated flux during the friction stir joining of high-density polyamide 6 (PA6) polymer were investigated. The computational fluid dynamics (CFD) method was employed to simulate the thermomechanical phenomena during the friction stir joining (FSJ) process of PA6. A developed model was used to consider the...
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Deformable model of a butterfly in motion on the example of Attacus atlas
PublicationInsect wings can undergo significant chordwise (camber) as well as spanwise (twist) deformation during flapping flight but the effect of these deformations is not well understood. The shape and size of butterfly wings leads to particularly large wing deformations, making them an ideal test case for investigation of these effects. High-speed videogrammetry was used to capture the wing kinematics and deformations. The movements of...
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On the non-linear dynamics of torus-shaped and cylindrical shell structures
PublicationIn this study, the non-linear dynamic analysis of torus-shaped and cylindrical shell-like structures has been studied. The applied material is assumed as the functionally graded material (FGM). The structures are considered to be used for important machines such as wind turbines. The effects of some environmental factors on the analysis like temperature and humidity have been considered. The strain field has been calculated in...
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Thermal and technological aspects of double face grinding of C45 carbon steel
PublicationIn grinding, the contact zone temperature is a decisive factor influencing the achievable surface quality and the grinding tool wear. In contrast to other grinding processes, only few information regarding double face grinding with planetary kinematics when processing steel is known up to date. Since the successive substitution of in-dustrial double-sided lapping processes by double-sided grinding, it has become necessary to the...
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Design Analysis of Micro Gas Turbines in Closed Cycles
PublicationThe problems faced by designers of micro-turbines are connected with a very small volume flow rate of working media which leads to small blades’ height and high rotor speed. In the case of gas turbines this limitation can be overcome by the application of a closed cycle with very low pressure at the compressor inlet (lower than atmospheric pressure). In this way we may apply a micro gas turbine unit of accepted efficiency to work...
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How can HSR promote inter-city collaborative innovation across regional borders?
PublicationMany studies have shown that high-speed rail (HSR) can reshape the spatial pattern of economic geography. However, there needs to be more logical argumentation and rigorous empirical design on the paths and mechanisms involved. This paper considers the impact of the border effect on HSR links and innovation clusters from the perspective of inter-regional collaborative innovation. It provides a logical and compact theoretical...
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Effect of Thermal Treatment and Erosion Aggressiveness on Resistance of S235JR Steel to Cavitation and Slurry
PublicationS235JR steel is used in many applications, but its resistance to the erosion processes has been poorly studied. To investigate this resistance, cavitation, and slurry erosion tests were conducted. These tests were carried out at different erosion intensities, i.e., different flow rates in the cavitation tunnel with a system of barricades and different rotational speeds in the slurry pot. The steel was tested as-received and after...
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A ship domain-based model of collision risk for near-miss detection and Collision Alert Systems
PublicationThe paper presents a new model of ship collision risk, which utilises a ship domain concept and the related domain-based collision risk parameters. An encounter is here described by five variables representing: degree of domain violation (DDV), relative speed of the two vessels, combination of the vessels’ courses, arena violations and encounter complexity. As for the first three variables, their values can be directly computed...
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The Optical Coherence Tomography and Raman Spectroscopy for Sensing of the Bone Demineralization Process
PublicationThe presented research was intended to seek new optical methods to investigate the demineralization process of bones. Optical examination of the bone condition could facilitate clinical trials and improve the safety of patients. The authors used a set of complementary methods: polarization-sensitive optical coherence tomography (PS-OCT) and Raman spectroscopy. Chicken bone samples were used in this research. To stimulate in laboratory...
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An optimal designed experiment for the alkaline hydrolysis of feather keratin
PublicationFeathers, burdensome waste from the poultry industry, can be a cheap source of keratin, a protein with excellent physico- chemical, biological, and mechanical properties. Acid and alkaline hydrolyses are usually adopted for isolation of keratin from its natural resources. This study aimed at assessing the statistically significant effect of input variables in the alkaline hydrolysis of keratin from chicken feathers on the process...
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Determining horizontal curvature of railway track axis in mobile satellite measurements
PublicationThe article discusses the applicability of a novel method to determine horizontal curvature of the railway track axis based on results of mobile satellite measurements. The method is based on inclination angle changes of a moving chord in the Cartesian coordinate system. In the presented case, the variant referred to as the method of two virtual chords is applied which consists in manoeuvring with only one GNSS (Global Navigation...
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A comprehensive review on Ginger (Zingiber officinale) as a potential source of nutraceuticals for food formulations: Towards the polishing of gingerol and other present biomolecules
PublicationCurrently, ginger is one the most consumed plants when dealing with the treatments of various illnesses. So far, it is known that various biologically active molecules, such as gingerols, shogaols and zingerone, among others, are the main responsible for specific biological activities, opening a new window for its utilization as a nutraceutical in foods. In pioneering extraction processes, solvent extraction has been initially...
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Projekt systemu sterowania dwukołowym robotem balansującym
PublicationW niniejszym artykule rozważony został problem sterowania dwukołowym robotem balansującym. Celem zaprezentowanych prac było zaprojektowanie systemu sterowania tego typu obiektem z wykorzystaniem metod nowoczesnej teorii sterowania. W ramach syntezy, bazując na wyprowadzonym w oparciu o zasady dynamiki Newtona modelu, dobrana została struktura systemu sterowania w postaci regulatora wykorzystującego sprzężenie zwrotne od stanu oraz...
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Wizyjny system monitoringu stanu nakładek stykowych odbieraków prądu
PublicationEksploatowane do niedawna w Polsce nakładki pantografów kolejowych były wykonywane w postaci styków miedzianych. Na początku 2011 r. przeprowadzono kompleksową zmianę typu nakładek stykowych, stosowanych przez operatorów korzystających z infrastruktury PKP PLK S.A., z miedzianych na metalizowane węglowe. Wraz z wprowadzeniem nakładek węglowych istnieje potrzeba opracowania nowych metod diagnostyki tego istotnego elementu toru zasilania...
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Funkcjonowanie zespołów napędu hydraulicznego maszyn w niskich temperaturach otoczenia
PublicationW pracy przedstawiono cztery warianty klasyfikacji rozruchów oziębionego napędu hydraulicznego. Pierwsza sytuacja dotyczy zagadnienia, w którym wszystkie zespoły układu napędowego wraz z olejem mają taką samą niską temperaturę podczas rozruchu. Pozostałe warianty odnoszą się do rozruchu w warunkach szoku termicznego wywołanych zasilaniem ciepłym czynnikiem roboczym oziębionych zespołów hydraulicznych. Rozruch zespołów...
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Uniqueness or uniformity - studies of media architecture
PublicationA development of media architecture is presented in light of to such phenomena as aesthetization, consumerism and digitization. This article deals with media architecture in commercial spaces. Media solutions impact on the architectural skin, making it into visible and dynamic points of the image of a post-modern city. This article presents the specificity of media solutions, depending on the function of commercial activity buildings...
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Non-conventional approach in single-sided lapping process: kinematic analysis and parameters optimization
PublicationThe lapping process is strongly affected by a number of input parameters. One of the fundamental mechanical processes in lapping is the abrasive effect of particles. In order to examine the influence of the kinematic parameters on the lapping uniformity of unconventional single-sided machine, numerical simulations of particles sliding trajectories are performed. Changing the kinematic parameters, e.g., rotational velocities or...
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The Emission and Combustion Characteristics of Marine Diesel Engine with Extreme Throttled of Air or Exhaust Ducts
PublicationPresented paper shows the results of the laboratory tests on the relationship between the extreme throttling of both air intake duct and exhaust gas duct and gaseous emission from the marine engine. The object of research is a laboratory, 4-stroke, DI diesel engine, operated at loads from 50 kW to 250 kW at a constant speed equal to 750 rpm. During the laboratory tests the thermodynamic and exhaust gas emission characteristics...
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Deep neural networks for human pose estimation from a very low resolution depth image
PublicationThe work presented in the paper is dedicated to determining and evaluating the most efficient neural network architecture applied as a multiple regression network localizing human body joints in 3D space based on a single low resolution depth image. The main challenge was to deal with a noisy and coarse representation of the human body, as observed by a depth sensor from a large distance, and to achieve high localization precision....
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An Ultra-Low-Energy Analog Comparator for A/D Converters in CMOS Image Sensors
PublicationThis paper proposes a new solution of an ultra-low-energy analog comparator, dedicated to slope analog-to-digital converters (ADC), particularly suited for CMOS image sensors (CISs) featuring a large number of ADCs. For massively parallel imaging arrays, this number may be as high as tens-hundreds of thousands ADCs. As each ADC includes an analog comparator, the number of these comparators in CIS is always high. Detailed analysis...
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Identification of Emotional States Using Phantom Miro M310 Camera
PublicationThe purpose of this paper is to present the possibilities associated with the use of remote sensing methods in identifying human emotional states, and to present the results of the research conducted by the authors in this field. The studies presented involved the use of advanced image analysis to identify areas on the human face that change their activity along with emotional expression. Most of the research carried out in laboratories...
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A new approach to a fast and accurate design of microwave circuits with complex topologies
PublicationA robust simulation-driven design methodology of microwave circuits with complex topologies has been presented. The general method elaborated is suitable for a wide class of N-port unconventional microwave circuits constructed as a deviation from classic design solutions. The key idea of the approach proposed lies in an iterative redesign of a conventional circuit by a sequential modification and optimisation of its atomic building...
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Rendezvous of heterogeneous mobile agents in edge-weighted networks
PublicationWe introduce a variant of the deterministic rendezvous problem for a pair of heterogeneous agents operating in an undirected graph, which differ in the time they require to traverse particular edges of the graph. Each agent knows the complete topology of the graph and the initial positions of both agents. The agent also knows its own traversal times for all of the edges of the graph, but is unaware of the corresponding traversal...
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Rendezvous of Heterogeneous Mobile Agents in Edge-Weighted Networks
PublicationWe introduce a variant of the deterministic rendezvous problem for a pair of heterogeneous agents operating in an undirected graph, which differ in the time they require to traverse particular edges of the graph. Each agent knows the complete topology of the graph and the initial positions of both agents. The agent also knows its own traversal times for all of the edges of the graph, but is unaware of the corresponding traversal...
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Framework Reuse - Heaven or Hell
PublicationObject-oriented frameworks have almost completely dominated the world of business applications. Frameworks are widely considered to be helpful and are designed to speed up creation of applications. However, when trying to apply a framework for a particular application, it often turns out that this is not as easy as it seemed at the beginning. It takes time to become familiar with the framework, with its concepts and the standard...
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Design and investigations of a micro-turbine flow part
Publication-generative micro-power plant with the HFE7100 as a working medium was designed and built for experimental investigations. The heat output of the plant was assumed equal to 20 kW, while the electric output amounted to about 3kW.In the paper a multi-stage micro-turbine with partial admission of all the stages is described in detail and the results of the particular experimental investigations and numerical calculations are shown,...
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Reservoir Influence on Pressure Wave Propagation in Steel Pipes
PublicationThe relation between the length of steel pipe and the pressure wave period in the system, reservoir-pipe-valve, is discussed. Experiments carried out for the short steel pipes showed that in such a system, the pressure wave celerity estimated using the measured wave cycles systematically increases with the increase of the pipe length. The observed differences can exceed even 90 m=s. As the pressure wave traveling in the pipe with...
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Improving the CPX method by specifying reference tyres and including corrections for rubber hardnes and temperature
PublicationRecently completed work in the EU project ROSANNE and in working group ISO/TC43/SC1/WG33 has allowed substantial improvements to measurements made by the Close-Proximity (CPX) method, intended for measurement of noise properties of road surfaces.The paper summarizes the experimental work and describes the conclusions and implementation in ISO/FDIS 11819-2 (CPX method) and in the supporting ISO (draft) Technical Specifications 11819-3...
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On possible applications of media described by fractional-order models in electromagnetic cloaking
PublicationThe purpose of this paper is to open a scientific discussion on possible applications of media described by fractional-order (FO) models (FOMs) in electromagnetic cloaking. A 2-D cloak based on active sources and the surface equivalence theorem is simulated. It employs a medium described by FOM in communication with sources cancelling the scattered field. A perfect electromagnetic active cloak is thereby demonstrated with the use...
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PRINCIPLES OF ARTIFICIAL INTELLIGENCE APPLICATION IN CONTROL OF THE ENTERPRISE
PublicationThe implementation of the tasks of evaluating historical financial information, the control or audit of business activities are based primarily on professional judgments about the object of study of a professional accountant or auditor. Their findings are drawn on the basis of the study of documents, the use of audit evidence, risk assessment, etc. There is always a probability (and rather high) that professional judgment will...
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Decomposition of the induced magnetism degaussing problem for fast determination of currents in demagnetization coils wrapped outside an object under arbitrary external field conditions
PublicationSafe passage of ships in the presence of sea mines can be ensured by limiting or reducing the ship’s magnetic footprint. For vessels with plastic hulls, the main component that requires magnetic damping is the engine. Demagnetization of such an object can be achieved by wrapping it with coils and setting the direct current appropriately. For each specific geographic location, the currents in the coils can be determined iteratively...
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Modelowanie zmiennej krzywizny na długości toru zwrotnego rozjazdu
PublicationW pracy została przedstawiona analityczna metoda wyznaczania krzywizny toru zwrotnego rozjazdu kolejowego posiadającego na swojej długości odcinki zmiennej krzywizny. Taki rozjazd jest dedykowany w głównym stopniu kolejom dużych prędkości. Rozpatrzono dwa odrębne przypadki obejmujące liniowy przebieg krzywizny oraz przebieg nieliniowy, w postaci wielomianowej. Uzyskane rozwiązania problemu pozwalają na przyjmowanie dowolnych wartości...
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Medical-Grade PCL Based Polyurethane System for FDM 3D Printing—Characterization and Fabrication
PublicationThe widespread use of three-dimensional (3D) printing technologies in medicine has contributed to the increased demand for 3D printing materials. In addition, new printing materials that are appearing in the industry do not provide a detailed material characterization. In this paper, we present the synthesis and characterization of polycaprolactone (PCL) based medical-grade thermoplastic polyurethanes, which are suitable for forming...
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Sensorless field oriented control for five-phase induction motors with third harmonic injection and fault insensitive feature
PublicationThe paper presents a solution for sensorless field oriented control (FOC) system for five-phase induction motors with improved rotor flux pattern. In order to obtain the advantages of a third harmonic injection with a quasi-trapezoidal flux shape, two vector models, α1–β1 and α3–β3, were transformed into d1– q1, d3– q3 rotating frames, which correlate to the 1st and 3rd harmonic plane respectively. A linearization approach of the...
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Comparative study on the effectiveness of various types of road traffic intensity detectors
PublicationVehicle detection and speed measurements are crucial tasks in traffic monitoring systems. In this work, we focus on several types of electronic sensors, operating on different physical principles in order to compare their effectiveness in real traffic conditions. Commercial solutions are based on road tubes, microwave sensors, LiDARs, and video cameras. Distributed traffic monitoring systems require a high number of monitoring...
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ENERGY ANALYSIS OF PROPULSION SHAFT FATIGUE PROCESS IN ROTATING MECHANICAL SYSTEM PART I TESTING SIGNIFICANCE OF INFLUENCE OF SHAFT MATERIAL FATIGUE EXCITATION PARAMETERS
PublicationThe article discusses the problem of mathematical modelling of energy conversion processes in a rotating mechanical system for the purpose of identifying fatigue states of propulsion shafts in this system. A simplified physical model of the analysed system, constructed in an appropriate scale, has made the basis for the experimental research. The research programme took into consideration mechanical fatigue excitation of the model...
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Temperature influence on tyre/road noise on poroelastic road surface based on laboratory measurements
PublicationThe temperature effect on measured tyre/road noise is very important phenomena as it may lead to significant errors in measurement results due to substantial influence of this parameter on the obtained values. It depends mainly on the particular tyre-road combination. It is different for dense and porous as well as for bituminous and cement concrete pavements. It differs also depending on tested tyre. The correction procedure for...
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Novel analysis methods of dynamic properties for vehicle pantographs
PublicationTransmission of electrical energy from a catenary system to traction units must be safe and reliable especially for high speed trains. Modern pantographs have to meet these requirements. Pantographs are subjected to several forces acting on their structural elements. These forces come from pantograph drive, inertia forces, aerodynamic effects, vibration of traction units etc. Modern approach to static and dynamic analysis should...
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Innovative Research Into Road Restraint Systems
PublicationKey to understanding the needs and building road infrastructure management tools to prevent and mitigate run-off-road accidents is to identify hazards and their sources which are a result of wrong design, construction, installation and maintenance of road restraint systems [1]. Building such tools requires advanced studies with field tests, simulations and models to demonstrate the effects of selected parameters on road user safety...
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Dynamic coloring of graphs
PublicationDynamics is an inherent feature of many real life systems so it is natural to define and investigate the properties of models that reflect their dynamic nature. Dynamic graph colorings can be naturally applied in system modeling, e.g. for scheduling threads of parallel programs, time sharing in wireless networks, session scheduling in high-speed LAN's, channel assignment in WDM optical networks as well as traffic scheduling. In...
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TMSCl Promoted Acylation of Amines with 5-(α-amino- α'-hydroxy)methylene Meldrum's Acids - Elucidation of Mechanism.
PublicationRecently we have observed accelerating influence of trimethyl silyl chloride addition on the rate of the reactions of 5-(α-amino- α'-hydroxy)methylene Meldrum's Acids with amines, particularly in the case of highly basic amines. However the nature of the aforementioned process remain unexplained. In proposed communication we wish to report insightful elucidation of this mechanism. The reaction under investigation involves simply...
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Efficiency of thermomechanical reclaiming of ground tire rubber conducted in counter-rotating and co-rotating twin screw extruder
PublicationIn this article the results of research on a continuous thermomechanical reclaiming process of ground tire rubber (GTR) conducted in a twin screw extruder are presented. The effects of the rotation direction (co-rotating/counter-rotating), design of co-rotating plasticizing units and the rotational speed of the screws on the extruder working parameters, sol fraction and the degree of reclaiming in the obtained products were described....