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Five strategies for the uncertain future
PublicationThe paper focuses on strategies of architectural education the in an era of increasing mobility, emerging alternative energy solutions and prevailing tone of uncertainty concerning future development of cities. Five strategies implemented at the Faculty of Architecture, Gdańsk University of Technology have been presented.
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Selective Harmonic Elimination PWM For a Cascaded Multi-level Inverter
PublicationThis paper deals with the selective harmonic elimination pulse width modulation (SHE-PWM) technique. This technique is used for the elimination of selected dominant low order harmonics in the multi-level inverter output voltage. The presence of these harmonics is the essential drawback of such kind of inverters; especially when it is used for the control of different AC drivers. The SHE-PWM is based...
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DIGITAL HYDRAULICS CIRCUIT BASED ON PWM FUNCTION FOR CONTROLLING HYDRAULIC ACTUATOR POSITION
PublicationHydraulic systems are used in many different industries, such as multi-source hydrostatic drive systems. In traditional hydraulic systems, a proportional servo valve is used to control the position of hydraulic actuators. The low energy efficiency and high cost of these control valves are two major problems with these systems. Digital hydraulics is one of the most unique ideas on how to solve these problems. Researchers like digital...
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Optimized Space-Vector Modulation Schemes for Five-Phase Precision Low-Speed Drives with Minimizing the Stator Current Ripple
PublicationOne of the main ways to improve the quality of a precision electric drive is minimization of the stator current pulsations generated by the voltage inverter. The solution of this problem can be achieved by using of multiphase inverters, as well as improving control algorithms. This paper considers the influence of the space-vector modulation algorithm with different switching sequences of basic vectors on the stator current pulsations...
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Interrelations between Travel Patterns and Urban Spatial Structure of the Largest Russian Cities
PublicationThe study presented within this dissertation involves the analysis of the relationship between urban spatial structure and travel patterns in the largest Russian cities. It is an empirical investigation of how the spatial structure, formed during the Soviet and post-Soviet periods, affects the travel patterns in the largest cities of contemporary Russia. It aims to determine what measures, both urban structure and transportation...
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Comparative analysis of three‐phase dual active bridge converter with different transformer topology and modern universal control for DC microgrids
PublicationThe presented work discusses issues related to the use of modern multiphase topologies of Dual Active Bridge (DAB)-type converters. Converters of this type are widely used in most DC microgrid applications. The introduction emphasizes a comparative analysis between single-phase and multi-phase DAB topologies within high-power DC microgrids, delving into their respective advantages, drawbacks, design procedures, and considerations...
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Evaluation of IEEE 802.21 Handover between IEEE 802.11 and UMTS Networks
PublicationThe paper presents IEEE 802.21 - the ongoing standard for network handovers - illustrating its functional features, and considering and simulating a set of scenarios of mobile stations moving between IEEE 802.11 and UMTS networks. In order to evaluate the performance of IEEE 802.21 hanover packet loses and switching delays caused by hanover procedures are investigated. The authors discuss example results of simulation experiments...
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Smart Blue Cities
PublicationThis paper presents the concept of Smart Cities from the perspective of those located by water, considering if there are more major differences in the way the concept is implemented in coastal cities, as opposed to those located anywhere else. It proves possible to point to such differences, in relation to the three key areas of mobility, the environment and living. Further consideration is given to specific legal and cross-cultural...
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Water-mediated long-range interactions between the internal vibrations of remote proteins
PublicationIt is generally acknowledged that the mobility of protein atoms and the mobility of water molecules in the solvation layer are connected. In this article, we answer the question whether a similar interdependence exists between the motions of atoms of proteins separated by the hydration layers of variable thickness. The system consisted of a kinesin catalytic domain and a tubulin dimer. It was studied using molecular dynamics simulations....
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Study of the effect of adiabatic heating on the operation of the electrodynamic actuator
PublicationElectrodynamic actuators are used in hybrid switching systems where a very quick contact separation as well as operation repeatability and long-term reliability are required. The article presents selected results of thermal studies in the electrodynamic drive system. Study was carried out on the basis of the 3D electromagneto-thermal model implemented in the Ansys_Maxwell environment. The present model allows to determine the critical...
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Hybrid Approach to Networked Control System
PublicationEffcient control of Networked Control System (NCS) is a challenge, as the control methods need to deal with non-deterministic variable delays and data loss. This paper presents a novel hybrid approach to NCS where Model Predictive Control (MPC) is applied as a main controller and implicit switching MPC is used for data transmission control in event-driven shared communication medium, leading to complex control system with active...
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Simulation Model of IMS/NGN with Transport Stratum Based on MPLS Technology
PublicationIn the paper we continue our research on traffic modelling in the Next Generation Network (NGN) architecture, which includes the IP Multimedia Subsystem (IMS) elements. A simulation model of a single NGN domain with transport stratum based on the Multiprotocol Label Switching (MPLS) technology is proposed, which allows evaluation of mean response time of this stratum. The simulation model is applied to verify the results obtained...
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Multipulse inverter structures with low voltage distortion
PublicationA novel approach to the voltage source inverters (VSI) construction is presented in the paper. The invented inverter structures allow to operate several DC/AC converters in parallel resulting in lower voltage distortions at extremely low switching frequency. The research presented in the paper describes such a parallel operation of the VSI’s which is possible thanks to the use of coupled inductors. The eighteen-pulse three-level...
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Analysis of Residual Stresses and Dislocation Density of AA6082 Butt Welds Produced by Friction Sir Welding
PublicationThe Friction Stir Welding (FSW) method was employed to join AA6082 sheets. The welds were produced with different tool traverse speed (200 and 250 mm/min), rotational speed (1000 and 1250 RPM) and tool tilt angle (0 and 2 deg). Based on the analysis of XRD patterns, the total precipitation volume fractions in the nugget zones and the base material were calculated. The FSW process resulted in a reduction in the fraction of precipitates...
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Unusual dynamic properties of water near the ice-binding plane of hyperactive antifreeze protein
PublicationThe dynamical properties of solvation water of hyperactive antifreeze protein from Choristoneura fumiferana (CfAFP) are analyzed and discussed in context of its antifreeze activity. The protein comprises of three well-defined planes and one of them binds to the surface of ice. The dynamical properties of solvation water around each of these planes were analyzed separately; the results are compared with the dynamical properties...
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Wartość dodana akademickiej biblioteki „mobilnej” w kontekście programu Erasmus+ na przykładzie Biblioteki Politechniki Gdańskiej
PublicationMobilność wynikająca z założeń programu Erasmus+ w uczelniach i bibliotekach akademickich to wszelkie działania polegające na realizowaniu zagranicznych wyjazdów szkoleniowych w tzw. stażowych miejscach docelowych w krajach-sygnatariuszach programu. Erasmus+ w bibliotekach akademickich umożliwia szeroko pojęte doskonalenie zawodowe, rezultatem którego może być uzyskana wartość dodana uwidoczniona w nabywaniu nowych doświadczeń...
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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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Pulse-Width Modulation of Power Electronic DC–AC Converter
PublicationThe Second Edition of High Performance Control of AC Drives with Matlab®/Simulink delivers an updated and thorough overview of topics central to the understanding of AC motor drive systems. The book includes new material on medium voltage drives, covering state-of-the-art technologies and challenges in the industrial drive system, as well as their components, and control, current source inverter-based drives, PWM techniques for...
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Automatyczne urządzenia przełączające nn - oferta firmy Siemens
PublicationUkłady samoczynnego załaczania rezerwy zasilania (SZR), okrełslane w PN-EN 60947-6-1 jako automatyczne urządzenia przełaczające (ATSE ang. Automatic Transfer Switching Equipment) są przeznaczone do zapewnienia ciągłosci zasilania odbiorców energii elektrycznej. W artykule omówiono klasyfikację ATSE, budowę blokad aparatów wykonawczych oraz zalecane czasy zadzialania ATSE. Przedstawiono automatyczne urządzenia przełaczające oferowane...
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Automatyczne urządzenia przełączające niskiego napięcia
PublicationUkłady samoczynnego załaczania rezerwy zasilania (SZR), okrełslane w PN-EN 60947-6-1 jako automatyczne urządzenia przełaczające (ATSE ang. Automatic Transfer Switching Equipment) są przeznaczone do zapewnienia ciągłosci zasilania odbiorców energii elektrycznej. W artykule omówiono klasyfikację ATSE, budowę elektrycznych blokad aparatów wykonawczych oraz zalecane czasy zadzialania ATSE. Przedstawiono automatyczne urządzenia przełaczające...
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Blast Charge Technique as a Method of Soil Improving to Locate the New Supporting Runways
PublicationA quick and effective method of reinforcing the ground base designed for the construction of engineering structures used for performing various types of air operations was presented. It allows to use wastelands, wetlands, swamps, etc. for these purposes, thus creating a dispersed network of landing sites, increasing the access of large social groups to air transport and increasing their mobility.
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Modular multipulse voltage source inverters with integrating coupled reactors
PublicationA novel approach to the voltage source inverters (VSI) construction is presented in the paper. The invented inverter structures allow to operate several DC/AC converters in parallel resulting in lower voltage distortions at extremely low switching frequency. The research presented in the paper describes such a parallel operation of the VSI’s which is possible thanks to the use of coupled inductors. The eighteen-pulse and twenty-four-pulse...
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Sieć wielodomenowa wykorzystująca MPLS i SDN
PublicationTechnologia Wieloprotokołowej Komutacji Etykietowej (MPLS – MultiProtocol Label Switching) dostarcza odpowiednie mechanizmy wspierające proces zachowania jakości usług, jednak wymaga nadrzędnego elementu sterującego. Takim elementem może być kontroler zrealizowany w koncepcji Sieci Definiowanych Programowo (SDN – Software Defined Networking), wprowadzający abstrakcję, rozdzielającą płaszczyznę przekazywania od płaszczyzny sterowania....
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QoS Resource Reservation Mechanisms for Switched Optical Networks
PublicationThe paper regards the problem of resource reservation mechanisms for Quality of Service support in switched optical networks. The authors propose modifications and extensions for resources reservation strategy algorithms with resources pools, link capacity threshold and adaptive advance reservation approach. They examine proposed solutions in Automatically Switched Optical Network with Generalized Multi-Protocol Label Switching...
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Study on transmission quality in cellular 4G and 5G networks between 2019–2021: Impact of the COVID-19 pandemic on the level of provided services by operating base transceiver stations
PublicationThe COVID-19 pandemic has significantly limited user mobility, not least among students. Remote learning had a particular impact on resource allocation in relation to using terrestrial cellular networks, especially 4G systems in urban agglomerations. This paper presents the results of a quality evaluation of an outdoor environment, carried out between 2019 and 2021 on the campus of a technical university. Annual studies are conducted...
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Genetic and pharmacologic proteasome augmentation ameliorates Alzheimer’s-like pathology in mouse and fly APP overexpression models
PublicationThe proteasome has key roles in neuronal proteostasis, including the removal of misfolded and oxidized proteins, presynaptic protein turnover, and synaptic efficacy and plasticity. Proteasome dysfunction is a prominent feature of Alzheimer’s disease (AD). We show that prevention of proteasome dysfunction by genetic manipulation delays mortality, cell death, and cognitive deficits in fly and cell culture AD models. We developed...
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Study of Aliphatic Polyurethanes by the Low-Field 1H NMR Relaxometry Method with the Inversion of the Integral Transformation
PublicationIn this paper, the distributions of the 1H nuclear magnetic resonance (NMR) spin–lattice and spin–spin relaxation times are used to characterize the mobility of different sections of macromolecules of aliphatic polyurethanes and the cross-linking density of polymer chains. The NMR relaxometry method with inversion of integral transformation is applied to study the effect of poly (ethylene glycol) and glycerol phosphate calcium...
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Determination of metals in water samples by atomic absorption spectrometry and flame emission spectrometry
PublicationMetal species in environmental waters are relevant to characterize the metal toxicity, the mobility between different environmental compartments, and for remediation purposes in case of contamination. The concentration of many trace metals in natural water samples are generally at µg/l level. The paper describes determination of metals in water samples based on flame atomic emission and flame atomic absorption spectrometry.
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Quantitative Active Dynamic Thermal IR-Imaging and Thermal Tomography in Medical Diagnostic
PublicationPrinciples of Active dynamic thermal (ADT) IR-imaging and Thermal Tomography are described in details. Basic medical applications of this new modality are also discussed.
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Low harmonic multipulse voltage converters using coupled reactors
PublicationThis paper presents a novel approach to the multi pulse voltage converters (VC), especially voltage source inverters (VSI) and matrix converters (MC) based on several typical identical modules connected in parallel using coupled reactors. Such arrangements resulting in lower voltage distortions at extremely low switching frequency. The proposed arrangement was validated by simulation. Laboratory models of 18- and 24pulse 3-level...
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Modelowanie bezpiecznika rozłącznikowego w układach formowania impulsów wielkiej mocy
PublicationProblem modelowania bezpieczników o dużej dynamice wyłączania prądu jest zagadnieniem szeroko opisywanym w literaturze. Układy takie mogą być wykorzystane w szczególności do formowania impulsów wysokiego napięcia o wartościach rzędu setek kV, charakteryzujących się czasem trwania rzędu ułamka μs. W niniejszej pracy przedstawiono empiryczny model bezpiecznika wielotopikowego, rozszerzony w oparciu o wyniki badań eksperymentalnych.
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RECENT ADVANCES IN GRAPHENE APPLICATION FOR ELECTRONIC SENSING
PublicationThe great interest in graphene is caused by its potential for constructing various sensors exhibiting excellent parameters. The high carrier mobility and the unique band structure of graphene makes it promising especially in the field-effect transistors (GFET) applications. In this article, recent advances of the selected graphene-based sensor applications were presented and the possible directions for further investigations were...
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Proces zmiany sprzedawcy energii elektrycznej w Polsce
PublicationOstatnie kilkanaście lat w polskiej energetyce to okres dynamicznych zmian. Jednym z istotnych przykładów tych przemian jest liberalizacja rynku energii. Wprowadzone, w krajowej energetyce, mechanizmy rynku konkurencyjnego umożliwiają odbiorcom energii m.in. swobodny wybór sprzedawcy energii elektrycznej w formule TPA. W artykule przedstawiony został proces zmiany sprzedawcy bazujący na generalnej umowie dystrybucji (GUD). W trakcie...
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Dual Active Bridge (DAB) DC-DC converter for multilevel propulsion converters for electrical multiple units (EMU)
PublicationSemiconductor power devices made from silicon carbide (SiC) reached a level of technology enabling their widespread use in power converters. Two different approaches to implementation of modern traction converters in electric multiple units (EMU) have been presented in recent years: (i) 3.3-kV SiC MOSFET-based three-level PWM inverter with regenerative braking and (ii) 6.5-kV IGBT-based four-quadrant power electronic traction transformer...
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Genetic and pharmacologic proteasome augmentation ameliorates Alzheimer’s-like pathology in mouse and fly APP overexpression models
PublicationThe proteasome has key roles in neuronal proteostasis, including the removal of misfolded and oxidized proteins, presynaptic protein turnover, and synaptic efficacy and plasticity. Proteasome dysfunction is a prominent feature of Alzheimer’s disease (AD). We show that prevention of proteasome dysfunction by genetic manipulation delays mortality, cell death, and cognitive deficits in fly and cell culture AD models. We developed...
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Wpływ surfaktantu anionowego LAS na mobilność frakcji fosforu w osadzie czynnym w zmiennych warunkach fizyczno-chemicznych
PublicationPrzedstawiono wyniki badań wpływu anionowego surfaktantu LAS na mobilność frakcji fosforu w osadzie czynnym. Podstawową rolę w procesie uwalniania fosforu do cieczy nadosadowej w warunkach beztlenowych pełniły: frakcja związana z substancją organiczną i frakcja związana z żelazem.
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Growing role of walking and cycling and the associated risks
PublicationIncreasing the role of active mobility, including walking and cycling, is one of the tools for developing sustainable urban transport systems as recommended by the EU. The article describes the trends in pedestrian and bicycle traffic in Poland and its share in urban modal split. It identifies and describes the main sources of risks to pedestrian and cycle safety. Recommendations are...
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Estimation of interior-permanent-magnet-synchronous-motor rotor position by analysis of phase-current derivatives
PublicationThis paper describes an algorithm for estimation of IPMSM rotor angular position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Calculation of the motor position is performed in every PWM cycle. The standard SV-PWM method is used to determine...
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Solving the Problem of Dynamic Adaptability of Artificial Intelligence Systems that Control Dynamic Technical Objects
PublicationThis paper investigates the increase in the response speed and stability of artificial intelligence systems that control dynamic technical objects. The problem of calculating the optimal time of switching an artificial intelligence system between software classes by the criterion of the rigidity degree of the model of a control object is considered. The solution of this problem is proposed for the general case of the control object...
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Proces zmiany sprzedawcy energii elektrycznej w Polsce dla odbiorcy w gospodarstwie domowym
PublicationW publikacji przedstawiono proces zmiany sprzedawcy energii elektrycznej dla odbiorcy w gospodarstwie domowym, prowadzony w detalicznym segmencie rynku energii. Szczególny nacisk położono na proces bazujący na generalnej umowie dystrybucji dla usługi kompleksowej. Odniesiono się do wszystkich, istotnych regulacji mających zastosowanie do poruszanych kwestii, ze szczególnym uwzględnieniem zapisów instrukcji ruchu i eksploatacji...
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Giant Nernst effect in the incommensurate charge density wave state of P4W12O44
PublicationWe report the study of Nernst effect in quasi-low-dimensional tungsten bronze P4W12O44 showing a sequence of Peierls instabilities. We demonstrate that both condensation of the electronic carriers in the charge density wave state and the existence of high-mobility electrons and holes originating from the small pockets remaining in the incompletely nested Fermi surface give rise to a Nernst effect of a magnitude similar to that...
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Preconcentration and Analytical Methods for Determination of Methyl Tert-Butyl Ether and Other Fuel Oxygenates and Their Degradation Products in Environment: A Review
PublicationFuel oxygenates (FOs) are mainly ethers or alcohols which are added to gasoline either to boost the octane number or to make the fuel burning process more "cleaner" with increasing the oxygen content, or to obtain a combination of both effects. FOs are water soluble with high mobility in the environment which presence even at very low concentrations lower the quality of water making it unsafe or unpleasant due to their objectionable...
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Developing a Metropolitan Transport System—Exemplified by the Gdansk–Gdynia–Sopot Metropolitan Area
PublicationAs regional centres with metropolitan functions, metropolises grow and develop depending on how well they can meet the area’s transport needs internally and externally, a result of their socio-economic relations. The transport system of a metropolitan area must ensure that people and goods can move efficiently, effectively and environmentally friendly. Over the last ten years, the transport system of the Gdańsk–Gdynia–Sopot Metropolitan...
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Car-sharing: The Impact on Metropolitan Spatial Structures
PublicationMany examples from the past show that new technologies designed to solve particular problems can also create side effects generating new problems. Some unforeseen or unwanted results may influence space use and spatial structures. Car-sharing is an invention to compete with car ownership. It drastically rise efficiency of car use, reducing the number of vehicles per users. Diffusion of car-sharing is going to accelerate in the...
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INNOVATIVE RUN FLAT SYSTEMS
PublicationOne of the most essential threats to the mobility of wheeled vehicles is their relatively high sensitivity to tire damage. Tires can be damaged as a result at vehicle-targeting fire, after running on a mine or an improvised charge. The purpose of the article is to analyze the current technical solutions in wheeled vehicle tires, allowing for the unobstructed use of the vehicle despite the damage of one or several tires (RUN FLAT...
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Quality of Service in ASON/GMPLS Network with Hierarchical Control Plane Structure
PublicationThe paper presents the problem of quality of service for hierarchical control plane structure of Automatically Switched Optical Network (ASON) utilizing Generalized Multi-Protocol Label Switching (GMPLS). The approach is implemented to control the multidomain network with required quality of service, in a use case of incomplete domain network information. The authors examine different factors, including resource reservation algorithms...
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Performance Evaluation of Preemption Algorithms in MPLS Networks
PublicationPreemption is a traffic engineering technique in Multiprotocol Switching Networks that enables creation of high priority paths when there is not enough free bandwidth left on the route. Challenging part of any preemption method is to select the best set of paths for removal. Several heuristic methods are available but no wider comparison had been published before. In this paper, we discuss the dilemmas in implementing preemption...
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IPMSM rotor position estimator based on analysis of phase current derivatives
PublicationThis paper describes an algorithm for estimation of IPMSM angular rotor position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Algorithm is characterised by a very simple formulae. The calculation of rotor position is performed in every PWM...
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Performance Evaluation of Control Plane Functions in ASON/GMPLS Architecture
PublicationIt is assumed that demands of information society could be satisfied by architecture ASON/GMPLS comprehended as Automatically Switched Optical Network (ASON) with Generalized Multi-Protocol Label Switching (GMPLS) protocols. Introduction this solution must be preceded performance evaluation to guarantee society expectations. Practical realization is expensive and simulations models are necessary to examine standardized propositions....
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Azo group(s) in selected macrocyclic compounds
PublicationAzobenzene derivatives due to their photo- and electroactive properties are an important group of compounds finding applications in diverse fields. Due to the possibility of controlling the trans–cis isomerization, azo-bearing structures are ideal building blocks for development of e.g. nanomaterials, smart polymers, molecular containers, photoswitches, and sensors. Important role play also macrocyclic compounds well known for...