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Search results for: dynamics of pneumatic drive
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Experimental research on technical fabric of the Forest Opera Roof in Sopot
PublicationThe experimental analysis of the technical fabric Valmex is presented. The study involves uniaxial tensile, cyclic, rheological and biaxial tests. Some of the main differencies between two types of the analysed material have been identified. Mechanical properties of the textile have been modeled by the viscoelastic standard model with quite good effect.
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Identification of inertia, damping and stiffness parameters for low pressure steam turbine framework.
PublicationW pracy przedstawiono metodę identyfikacji masy tłumienia i sztywności kadłuba części niskoprężnej turbiny parowej 200MW.
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Symbolic multibody models for digital-twin applications
PublicationSymbolic generation of multibody systems equations of motion appeared in the 1980s. In addition to their computational advantage over their numerical counterparts, symbolic models can be very easily and straightforwardly interfaced with a wide range of software environments and hardware devices. These two features place this approach in a pole position to participate and intervene in the design of digital twins for systems such...
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Modeling of Common Mode Currents Induced by Motor Cable in Converter Fed AC Motor Drives
PublicationInvestigation of conducted EMI generation in AC motor fed by pulse width modulated frequency converters requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. Motor voltage transients and related common mode currents are significantly correlated with resonance effects occurring in load circuits. An analysis of frequency converter load impedance-frequency characteristics...
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A unified approach to the analysis of electric energy and fuel consumption of cars in city traffic
PublicationForecasting fuel and electricity consumption is an important factor determining the direction of changes in road engineering solutions, traffic management, selection of routes for public transport and development more efficient car drive systems. With a reliable and easy-to-use computational tool, it is possible to reduce the consumption of primary energy sources and reduce the emission of toxic compounds in cities. An analysis...
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Numerical modelling of moored floating structures using SPH. Preliminary results
PublicationThis article presents partial results of the works carried out under the research project "The development of the methodof modeling the dynamics of the floating (offshore) objects subjected to the environment influence", which aims at developing computational methods for modeling the dynamics of offshore structures.The article contains the description of the method of modeling the hydrodynamic impacts using SPH method and the description...
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On various modelling approaches to real-time visualisation of blood flow
PublicationThis paper reviews various modelling approaches to real-time visualisation of blood flow. These include classic, macroscale approach based on the momentum conservation equation together with a proper constitutive equation. Moreover, modern micro- and mesoscale approaches, such as molecular dynamics and dissipative particle dynamics, are discussed. Advantages and disadvantages of the discussed methods are highlighted with particular...
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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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Kazi Amirul Hossain
PeopleI am a PhD graduate from Gdańsk University of Technology and currently a postdoctoral researcher at IRB Barcelona (Prof. Modesto Orozco lab). My academic focus is on computational biophysics, particularly Molecular Dynamics (MD) and statistical mechanics. I also have expertise in molecular modeling techniques like Molecular Docking, Homology Modeling, and QSAR. I hold an M.S. (Pharm) from NIPER, Kolkata, where I was awarded the...
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Krzysztof Jan Kaliński prof. dr hab. inż.
PeopleKrzysztof J. Kaliński completed his MSc study at Gdańsk University of Technology (GUT) Faculty of Production Engineering (1980, result – get a first). He obtained PhD at GUT Faculty of Machine Building (1988, result – get a first), DSc at GUT Faculty of Mechanical Engineering (ME) (2002, result – get a first), and professor’s title – w 2013 r. In 2015 r. he became full professor, and since 2019 - professor.His research area includes:...
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Reputacja i zaufanie w systemach teleinformatycznych z podmiotami anonimowymi podejście dynamiczne
PublicationAbstrakcją współczesnego systemu teleinformatycznego jest system wieloagentowy z autonomicznymi, racjonalnymi i wirtualnie anonimowymi agentami wchodzącymi we wzajemne interakcje dla wymiany usług. W referacie uzasadniono konieczność projektowania dla niego podsystemu budowy reputacji i zaufania oraz odpowiednich analiz w ujęciu dynamicznym. Dokonano przeglądu motywacyjnie zgodnych mechanizmów uczciwego raportowania usług oraz...
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Analysis of Rolling Resistance of Tires With Run Flat Insert
PublicationRun flat properties are required for tires intended for special applications like military or rescue vehicles. Run-Flat inserts make possible to drive a car or truck, with certain restrictions, also when inflation pressure is very low or non-existing (after tire damage). Rolling resistance of tires rolling the inserts increases considerably in relation to the rolling resistance of properly inflated tires. This paper presents results...
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Analysis and characterization of coordination compounds by resonance Raman spectroscopy
PublicationResonance Raman spectroscopy has become a powerful tool to study excited-state geometries, excited-state charge distributions and photoinduced reaction dynamics in coordination compounds. Due to their rich photophysical properties coordination compounds are utilized for a variety of applications ranging from DNA sensing to photocatalysis. This review features recent applications of various resonance Raman scattering techniques...
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Broken Rotor Symptons in the Sensorless Control of Induction Machine
PublicationInverter fed sensorless controlled variable speed drives with induction machine are widely used in the industry applications, also in wind power generation and electric vehicles. On-line self diagnostic systems implementation is needed for early stage fault detection and avoiding a critical fault. Diagnostic algorithms in modern DSP-based controllers can operate simultaneously with control system functions. In the closed-loop controlled...
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Napęd z silnikiem indukcyjnym i 4-gałęziowym falownikiem SiC do turbosprężarek powietrza ogniw paliwowych dużej mocy
PublicationWysoka cena ogniw paliwowych utrudnia ich szerokie zastosowanie w transporcie i przemyśle. Należy szukać możliwości obniżenia ich kosztu również poprzez obniżenie kosztu i zwiększenie wydajności urządzeń pomocniczych ogniwa paliwowego (Balance of the Plant). Autorzy proponują aby w napędzie sprężarki powietrza, zastosować wysokoobrotowy silnik indukcyjny, który jest tańszy od stosowanych obecnie silników PMSM. W referacie zaproponowano...
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Changes in employment in the BPO/SSC sector in Poland in 2013-2019
Open Research DataEmployment in the BPO/SSC sector in 2019 was almost three times higher than in 2013. Throughout the analyzed period, employment grew year on year. The dynamics of changes ranged from 10% in 2019 to nearly 43% in 2016, when the highest increase in employment in the sector in nominal terms was at the level of 64,000.
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Hierarchical dissolved oxygen control for activated sludge processes
PublicationA hierarchical controller for tracking the dissolved oxygen reference trajectory in activated sludge processes is proposed and investigated. The removal of nitrogen and phosphorous from wastewater is considered. Typically, an aeration system itself is a complicated hybrid nonlinear dynamical system with faster dynamics compared to the internal dynamics of the dissolved oxygen in a biological reactor. It is a common approach to...
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Measurements of the mechanical system properties of "SpeedLine magnetic" ultra-fast robot prototype for IML labeling
Open Research DataThe mechanical system tests of the high-speed IML labeling robot "SpeedLine Magnetic" were carried out in order to analyze the effects of the drive system's operating parameters on vibration and noise.
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A Simplified SVPWM Technique for Five-leg Inverter with Dual Three-phase Output
PublicationThis article proposes a simplified space vector pulse-width modulation (SVPWM) technique five-leg inverter with dual three-phase output. An idea to fed the dual tree-phase machine by the multiphase voltage source inverters (VSIs) is not new. Dual- and multi-motor drive systems are widely used in the industry applications. The most popular fields are: electric vehicles (EVs) and traction systems. Moreover, the specific characteristic...
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Firing map for periodically and almost-periodically driven integrate-and-fire models: a dynamical systems approach
PublicationWe consider the Leaky Integrate-and-Fire and Perfect Integrator models of neuron’s dynamics with the input function being periodic and almost-periodic (in the sense of Stepanov). In particular we analyze properties and dynamics of the so-called firing map, which iterations give timings of consecutive spikes of a neuron. In case of a periodic input function we provide a detailed description of the sequence of interspike-intervals,...
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Metrological analysis of an computerized system of protection against electric shock in circuits with variable speed drives
PublicationDrive systems, that can be operated at variable speed, are equipped with power electronics converters. This causes distortion of the earth current, and consequently the need to take into account the use of proper protective devices in relation to earth current harmonics. This paper presents a system for protection against electric shock in circuits with power electronics converters and metrological analysis indicating the requirements...
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[IMe] Advanced numerical methods in mechanics
e-Learning Courses{mlang pl} Dyscyplina: inżynieria mechaniczna Zajęcia obowiązkowe dla doktorantów I i II roku Prowadzący: dr hab. inż. Krzysztof Tesch, prof. PG, dr hab. inż. Arkadiusz Żak, prof. PG Liczba godzin: 45 Forma zajęć: wykład {mlang} {mlang en} Discipline: mechanical engineering Obligatory course for 1st and 2nd-year PhD students Academic teachers: dr hab. inż. Krzysztof Tesch, prof. PG, dr hab. inż. Arkadiusz Żak, prof....
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Errors of a Linear Current Approximation in High-Speed PMSM Drives
PublicationCurrent sampling techniques and predictive algorithms used in the digital control of electric drives rely on a simple mathematical model that assumes linear current changes upon constant supplying voltages. This paper identifies rotor movement as a factor that makes this assumption invalid when the rotor covers an angular distance of a few tens of degrees during the control interval duration. The errors of the linear current approximation...
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Determination of equivalent circuit parameters of an induction motor using field calculation software
PublicationSimulation of the drive system comprising a power electronic converter and an induction motor requires that the equivalent circuit parameters of the motor are known. These parameters can be either measured or calculated. A method of calculation of self and mutual inductances that are parameters of a polyphase model of the motor is presented in the paper. All self-inductances and mutual inductances have been calculated using the...
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Broadband Modeling of Motor Cable Impact on Common Mode Currents in VFD
PublicationExamination of conducted EMI generation and propagation in AC motor drives fed by frequency converter requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. AC motor winding voltage transients and related common mode currents are significantly correlated with resonance effects occurring in converter's load circuits. Intensity levels of these phenomena depend...
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Rotation Triggers Nucleotide-Independent Conformational Transition of the Empty β Subunit of F1-ATPase
PublicationF1-ATPase (F1) is the catalytic portion of ATP synthase, a rotary motor protein that couples proton gradients to ATP synthesis. Driven by a proton flux, the F1 asymmetric γ subunit undergoes a stepwise rotation inside the α3β3 headpiece and causes the β subunits’ binding sites to cycle between states of different affinity for nucleotides. These concerted transitions drive the synthesis of ATP from ADP and phosphate. Here, we study...
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Dynamic Signature Vertical Partitioning Using Selected Population-Based Algorithms
PublicationThe dynamic signature is a biometric attribute used for identity verification. It contains information on dynamics of the signing process. There are many approaches to the dynamic signature verification, including the one based on signature partitioning. Partitions are the regions created on the basis of signals describing the dynamics of the signature. They contain information on the shape of the signature characteristic of a...
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Anti-plane waves in an elastic thin strip with surface energy
PublicationWe consider anti-plane motions of an elastic plate taking into account surface energy within the linear Gurtin–Murdoch surface elasticity. Two boundary-value problems are considered that describe complete shear dynamics of a plate with free faces or with free and clamped faces, respectively. These problems correspond to anti-plane dynamics of an elastic film perfectly or non-perfectly attached to a rigid substrate. Detailed analysis...
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Fitting the mobile device characteristics to the user's hearing preferences
PublicationA method for fitting the mobile computer audio characteristics to the user's hearing preferences is proposed. The process consists of two stages: calibration and dynamics processing. During the calibration phase the user performs a loudness scaling test giving their response regarding the perceived loudness. The dynamics processing made on above basis sets the loudness to the most comfortable level. The processing accounts both...
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A first-principles study of electron attachment to the fully hydrated bromonucleobases
PublicationDegradation mechanism of four brominated nucleobases (BrX), potential DNA radiosensitizers, is studied in explicit water solution, using ab initio molecular dynamics. Several fs long dynamics is needed to localize an electron on the nucleobase. Produced by electron attachment BrX anion radical degrades through the bromide anion abstraction, barrier-free (purines) or with low barrier (pyrimidines), to a reactive nucleobase radical....
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Medium-Voltage Drives: Challenges and existing technology
PublicationThe article presents an overview of state-of-art solutions, advances, and design and research trends in medium-voltage (MV) drive technologies - and also discusses the challenges and requirements associated with the use of such drives. The choice and deployment of MV drives in industries are associated with numerous requirements related to the front-end converter (grid side) and inverter (machine side). The focus is on solutions...
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Wpływ błędów parametrów modelu maszyny indukcyjnej na działanie rozszerzonego obserwatora prędkości
PublicationW artykule opisano metodę odtwarzania prędkości wirnika maszyny indukcyjnej przy wykorzystaniu rozszerzonego obserwatora prędkości. Zbadano wpływ błędów parametrów modelu maszyny indukcyjnej na właściwości dynamiczne obserwatora poprzez porównanie macierzy stanu obserwatora obarczonego oraz nieobarczonego błędami parametrów. Zbadany został także wpływ błędów parametrów na jakość odtwarzania zmiennych maszyny w stanie ustalonym.
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Application of road map of operating condition for estimation of fuel and electric energy consumption from city transport
PublicationThe paper presents procedure of data collecting and generation of road map of operating condition in the selected urban area. This map allows forecasting the selected vehicle operating parameters for the assumed road. The main parameters calculated using the road maps of operating conditions are: total energy spent to drive the selected vehicle, consumed fuel, travel time, average speed of travel, CO2 emissions. Presented example...
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СИСТЕМА КОНТРОЛЯ СОСТОЯНИЯ ИЗОЛЯЦИИ ЭЛЕКТРОПРИВОДОВ В СЕТЯХ С ГЛУХОЗАЗЕМЛЕННОЙ НЕЙТРАЛЬЮ (System of insulation status monitoring for electric drives in networks with a dead-earth neutral)
PublicationПредложен метод контроля изоляции частотно-регулируемых электроприводов в сетях с глухозаземленной нейтралью. Система контроля изоляции включается в момент остановки электропривода. Ключи инвертора коммутируются по специальному закону, и с помощью сигнала трансформатора тока, который изме- ряет ток во всех трех фазах привода одновременно, определяется ток утечки. Рассмотрена схема датчика тока утечки и приведены экспериментальные...
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An intelligent cellular automaton scheme for modelling forest fires
PublicationForest fires have devastating consequences for the environment, the economy and human lives. Understanding their dynamics is therefore crucial for planning the resources allocated to combat them effectively. In a world where the incidence of such phenomena is increasing every year, the demand for efficient and accurate computational models is becoming increasingly necessary. In this study, we perform a revision of an initial proposal...
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Broken rotor symptoms in the sensorless control of induction machine
PublicationThe purpose of this paper is to investigate the need for a universal method for sensorless controlled induction motor drive diagnosis. The increasing number of sensorless control systems in industrial applications require a universal method for the drive diagnosis, which provides reliable diagnostic reasoning independent of control system structure and state variables measurement or estimation method.Simulations and experimental...
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Modeling the impact of discretizing rotor angular position on computation of field-oriented current components in high speed electric drives
PublicationModern drives consist of alternating current electric motors, and the field-oriented control (FOC) of such motors enables fast, precise, and robust regulation of a drive's mechanical variables such as torque, speed, and position. The control algorithm, implemented in a microprocessor, requires feedback from motor currents, and the quality of this feedback is essential to a drive's control properties. Motor phase currents are sampled...
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Nilpotent singularities and chaos: Tritrophic food chains
PublicationLocal bifurcation theory is used to prove the existence of chaotic dynamics in two well-known models of tritrophic food chains. To the best of our knowledge, the simplest technique to guarantee the emergence of strange attractors in a given family of vector fields consists of finding a 3-dimensional nilpotent singularity of codimension 3 and verifying some generic algebraic conditions. We provide the essential background regarding...
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Topological-numerical analysis of a two-dimensional discrete neuron model
PublicationWe conduct computer-assisted analysis of a two-dimensional model of a neuron introduced by Chialvo in 1995 [Chaos, Solitons Fractals 5, 461–479]. We apply the method of rigorous analysis of global dynamics based on a set-oriented topological approach, introduced by Arai et al. in 2009 [SIAM J. Appl. Dyn. Syst. 8, 757–789] and improved and expanded afterward. Additionally, we introduce a new algorithm to analyze the return times...
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A Review of Reduction Methods of Impact of Common-Mode Voltage on Electric Drives.
PublicationIn this survey paper, typical solutions that focus on the reduction in negative effects resulting from the common-mode voltage influence in AC motor drive applications are re-examined. The critical effectiveness evaluation of the considered methods is based on experimental results of tests performed in a laboratory setup with an induction machine fed by an inverter. The capacity of a common-mode voltage level reduction and voltage...
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50’ Sail Catamaran with Hybrid Propulsion, Design, Theoretical and Experimental Studies
PublicationThe development of modern lithium batteries and propulsion systems now allows the use of complex propulsion systems for vessels of various sizes. As part of the research and implementation project, a parallel hybrid drive system was designed, built and then tested in the laboratory. The experimental studies conducted allowed for the measurements of power, fuel consumption and electric power distribution in various operating modes...
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Numerical investigations of the engine cooling system in a small power vesel pod propulsion system
PublicationThe development of electronics and electrotechnology enabled to put electric motors of the alternating current in the pod and to use them for the main drive of ships. A lot of heat which must be picked up from the system is a problem which is turning up at applying the system of this type. Many big ships lately contended with these problems. Building the small propeller for the boat powered with solar power we decided to check...
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Control of induction machine supplied by a current source inverter using the multi-scalar transformation and backstepping approach
PublicationThe paper describes the voltage control technique of squire-cage induction machines supplied by a current source inverter. The control system is based on new transformation of the electric drive system (machine and inverter) state variables to the multi-scalar variables form. The backstepping approach is used to obtain the feedback control law. The control system contains the structure of the observer...
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A NOVEL CONCEPT OF H2/O2 STEAM GENERATOR
PublicationThis paper presents an idea of hydrogen utilization to steam generation to drive a turbine and produce electricity or to supply a condenser as an element of heating system. Electrolysis process is considered as a source of hydrogen as well as oxygen. Hydrogen combustion with a stoichiometric ratio of pure oxygen produces steam at very high temperature. Steam temperature can be controlled by mixing the generated steam with liquid...
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A novel concept of H2/O2 steam generator
PublicationThis paper presents an idea of hydrogen utilization to steam generation to drive a turbine and produce electricity or to supply a condenser as an element of a heating system. Electrolysis process is considered as a source of hydrogen as well as oxygen. Hydrogen combustion with a stoichiometric ratio of pure oxygen produces steam at very high temperature. Steam temperature can be controlled by mixing the generated steam with liquid...
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Human subarachnoid space width oscillations in the resting state
PublicationAbnormal cerebrospinal fluid (CSF) pulsatility has been implicated in patients suffering from various diseases, including multiple sclerosis and hypertension. CSF pulsatility results in subarachnoid space (SAS) width changes, which can be measured with near-infrared transillumination backscattering sounding (NIR-T/BSS). The aim of this study was to combine NIR-T/BSS and wavelet analysis methods to characterise the dynamics of the...
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TRANSFORMATION OF WORLD ECONOMY AFTER THE END OF COLD WAR - Nowy
e-Learning CoursesThe course focuses the main trends of the world economy in the last 30 years. National and macro-regional, as well as sectorial case studies will be used to offer a clearer understanding of the main global dynamics. The approach is multidisciplinary and mainly qualitative, including economic and business history, international political economy, economic sociology and political science.
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TRANSFORMATION OF WORLD ECONOMY AFTER THE END OF COLD WAR - semester 2022-23
e-Learning CoursesThe course focuses the main trends of the world economy in the last 30 years. National and macro-regional, as well as sectorial case studies will be used to offer a clearer understanding of the main global dynamics. The approach is multidisciplinary and mainly qualitative, including economic and business history, international political economy, economic sociology and political science.
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Optimization of the femtosecond laser impulse for excitation and the spin-orbit-mediated dissociation in the NaRb molecule
Open Research DataHigh accuracy ab initio potential energy curves (1tSigma+, 2sSigma+, 1tPi), electronic transition dipole moment function (1tSigma+ - 1tPi), and spin-orbit coupling (2sSigma+ - 1tPi) have been calculated for the NaRb molecule. The time-dependent excitation and dissociation processes in the polar alkali diatomic NaRb molecule and the quantum properties...
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Determination of flow properties of a serial connection of a directional control valve with (C=5.7, b=0.32) and a air blow gun from changes in air pressure in a tank being emptied
Open Research DataThe aim of the study was to determine the flow properties of serial connection of pneumatic components.The experiments were to measure the pressure changes in a being emptied tank for a directional control valve and a air blow gun (with nozzle removed) arranged in-line. Three test configurations were used: (1) being emptied tank -> DCV -> ambient...