Search
displaying 1000 best results Help
Search results for: short-pulse equation
-
Collective angst and collective action for progressive city policies: study1
Open Research DataPaweł Adamowicz, the liberal mayor of Gdańsk, died on January 14, 2019, after being stabbed by a man who rushed onstage during a charity event. Three studies were carried out to analyze the predictors of willingness to engage in collective action for the support of the progressive city policies he initiated. In this study 1 (N = 214), the questionnaire,...
-
Number of statements issued about the intention to entrust the performance of work and the dynamics of change (%, year to year) in 2008-2018
Open Research DataWhen analyzing data on declarations of intention to entrust work to a foreigner, whose registration was completed at the end of 2017, with data on declarations on entrusting work to a foreigner, effective from 01/01/2018, it should noted that since 2018 the scope of data regarding statements. Currently they apply only to works that are not considered...
-
Surface treatment of C80U steel by long CO2 laser pulses
PublicationThe paper presents the results of laser-melted C80U steel. The processed steel was placed between two permanent magnets and laser beam whose scanning velocity was 10 mm/s. CO2 laser beam was working in pulse mode. Pulses were generated at 100% of the average preset power of 700W, with 45 ms irradiation, zero interval between pulses and beginning of pulse repetition upon the achievement of the average laser power. During the operation,...
-
The Influent Effects of Flow Rate Profile on thePerformance of Microbial Fuel Cells Model
PublicationThe energy contained in wastewaters has been identified as a promising sustainableenergy resource that could be harvested by using microbial fuel cells (MFC). When dealing with realwastewaters, the MFCs should be able to manage high flow rates and flow rates fluctuations. In thiswork, the short-term effects of the influent flow rate variations on the performance of a microbialfuel cell has been studied. With this aim, the influent...
-
Maturity Mismatch in the Polish Banking System and its Impact on the Economy
PublicationIn the article maturity mismatch in the Polish banking system is estimated based on the publicly available data. Then the impact on the economy is discussed. Based on Polish central bank’s data it may be estimated that between 1996 and 2012 the maturity gap increased significantly – average residual maturity of assets exceeds 6 years in 2012 (less than 2 years in 1996), while that of liabilities remains below 1 year. The gap...
-
Modelling of planar movement dynamics of upper limb
PublicationThe original model describing planar movement dynamics of upper limb is presented. The upper limb is modelled as two-joints system loaded by external forces and internal forces of striated skeletal muscles. A behaviour of each muscle is modelled as a system composed of serially linked rheologic fragments that have different mechanical properties. These muscle models allow us to simulate a behaviour of short fusiform muscle (3DOF...
-
Chalcogen bonding interactions in a series of aromatic selenocyanates
PublicationSelenium atoms in aromatic selenocyanates are characterized by the occurrence of two σ-holes, a stronger one in the prolongation of the NC–Se bond and a weaker one in the prolongation of the Ar–Se bond. The crystal structures of several bis(selenocyanato) derivatives, prepared by a method originally developed for ortho bis-substituted derivatives, illustrate very well this difference, with a short NC–Se⋯NC ChB interaction organizing...
-
Computational analysis of power-law fluids for convective heat transfer in permeable enclosures using Darcy effects
PublicationNatural convection is a complex environmental phenomenon that typically occurs in engineering settings in porous structures. Shear thinning or shear thickening fuids are characteristics of power-law fuids, which are non-Newtonian in nature and fnd wide-ranging uses in various industrial processes. Non-Newtonian fuid fow in porous media is a difcult problem with important consequences for energy systems and heat transfer. In this...
-
Modelowanie wymiany wody w zbiornikach hodowlanych przy użyciu zmodyfikowanego modelu tłokowego na przykładzie basenów hodowlanych dla fok
PublicationNiniejszy artykuł opisuje sposób prostego modelowania wymiany wody w basenach hodowlanych fokarium Stacji Morskiej Instytutu Oceanografii Uniwersytetu Gdańskiego. W celu rozpoznania warunków wymiany wody oraz udziału stref zastoiskowych w basenach posłużono się dwiema uzupełniającymi się metodami. Były to badania traserowe z wykorzystaniem znacznika fluororescencyjnego oraz komputerowe obliczenia rozkładu linii prądu z użyciem...
-
Effect of GIS parameters on modelling runoff from river basin. The case study of catchment in the Puck District
PublicationThe study was preceded to check the impact of the adopted digital elevation model resolution on the determination of catchment parameters and the further influence of the received information on calculations related to the hydrograph at the closing point of the basin after a synthetic 100-year precipitation episode. The study area are river basins located in the Puck commune convoying water directly to the Puck Bay. These studies...
-
Interactions of positrons with atoms and molecules
PublicationThe positron is the antiparticle of the electron. It has the same mass as the electron, but opposite charge. The understanding of the interactions of positrons with normal matter, like atoms and molecules, is of interest in various scientific fields, like nuclear medicine, plasma physics and astronomy. In this talk we will give a short introduction to some theoretical methods to describe the interactions of positrons with atoms...
-
Assessment of technical condition and repair of steel structure elements on the example of fire damage in a warehouse building
PublicationThe paper analyses a case study on the structural assessment of warehouse building partially damaged by fire caused by external source (fire of lorries close to the building). The authors focus on the site investigations and laboratory test results prior to assessing actual condition of the structural elements. Both strengthening concept and repair procedure of a steel column are addressed here. A short literature survey in the...
-
Magdalena Szuflita-Żurawska
PeopleHead of the Scientific and Technical Information Services at the Gdansk University of Technology Library and the Leader of the Open Science Competence Center. She is also a Plenipotentiary of the Rector of the Gdańsk University of Technology for open science. She is a PhD Candidate. Her main areas of research and interests include research productivity, motivation, management of HEs, Open Access, Open Research Data, information...
-
Electrochemical detection of 4,4',5,5'-tetranitro-1H,1'H-2,2'-biimidazole on boron-doped diamond/graphene nanowall electrodes
PublicationWe present a promising approach to the electroanalytical detection of a specific nitroaromatic explosive in landfill leachates (LLs) that originated from a municipal solid waste plant. The paper is focused but not limited to the sensing of 4,4',5,5'-tetranitro-1H,1'H-2,2'-biimidazole (TNBI) using differential pulse voltammetry and cyclic voltammetry. Highly electroactive nanocarbon was applied to determine low concentrations of...
-
Space vector modulation in multilevel inverters of the servo drives of the trajectory measurements telescopes
PublicationUsing the MatLab/Simulink mathematical model of a three-phase three-level voltage inverter, the influence of the space-vector modulation (SVM) algorithm on the pulsations of the current (torque) of an AC motor in the range of low rotation speeds is considered. It is shown that the SVM of the second kind does not provide a pulsations level comparable to the pulsations of a sinusoidal pulse-width modulation (SPWM), both in the static...
-
Design of the LLC Filter for AC Grid-Based Converter
PublicationThis paper emphasizes reducing harmonic distortion in the electrical current delivered by photovoltaic (PV) inverters to the power grid. It highlights the issue of significant harmonic components present in the output voltage of inverters, which is attributed to pulse width modulation (PWM) switching techniques. This necessitates the deployment of LCL filters as a strategic approach to limit current harmonics effectively. Additionally,...
-
Induction Generator with Direct Control and a Limited Number of Measurements on the Side of the Converter Connected to the Power Grid
PublicationThe article presents an induction generator connected to the power grid using the AC/DC/AC converter and LCL coupling filter. Three-level inverters were used in the converter, both from the generator side and the power grid side. The algorithm realizing Pulse Width Modulation (PWM) in inverters has been simplified to the maximum. Control of the induction generator was based on the Direct Field-Oriented Control (DFOC) method. At...
-
Jeffreys heat conduction in coupled semispaces subjected to interfacial heating
PublicationA Jeffreys heat conduction problem for coupled semispaces subjected to the action of an interfacial heat source was defined. An analytical solution of the problem was derived for a polynomial specific power of the heat source using the Laplace transform approach. The asymptotic and parametric analysis was performed for different ratios of thermal conductivities , thermal diffusivities , thermal relaxation times and coefficients...
-
Przyczółki mostowe z konstrukcją odciążającą z gruntu zbrojonego geosyntetykami
PublicationPrzegląd najważniejszych cech geotekstyliów i wyrobów pokrewnych, zastosowanych do budowy bloków odciążających ze szczególnym uwzględnieniem ich wytrzymałości długo i krótkookresowej oraz reologii. Określenie obciążeń działających na konstrukcję gruntową współpracującą z przyczółkiem; obciążenia normowe i rzeczywiste. Obliczenia konstrukcji z gruntu zbrojonego współpracującej z przyczółkiem
-
Justyna Szostak dr inż.
PeopleI Gdańsk University of Technology: Chair of the Rector’s Internationalization Committee (October 2020 - Present) Erasmus + Coordinator for students and staff members, Faculty of Applied Physics and Mathematics (Mar 2017 - Present) Dean's Proxy for Internationalization, Faculty of Applied Physics and Mathematics (October 2020 - Present) Coordinator of the International Relations Office of the Faculty of Applied Physics and...
-
Numerical Evaluation of Dynamic Response of a Steel Structure Model under Various Seismic Excitations
PublicationThe present paper reports the results of the study, which was designed to perform a numerical evaluation of dynamic response of a single-storey steel structure model. The experimental model was previously subjected to a number of different earthquake ground motions during an extensive shaking table investigation. The analyzed structure model was considered as a 1-DOF system with lumped parameters, which were determined by conducting...
-
Identification of Shear Modulus Parameters of Half-space Inhomogeneous by Depth
PublicationThe paper propose a method for determining of the parameters of the exponential shear modulus of a functionally graded half-space based on the solution of the problem of a pure shear of an elastic functionally graded half-space by a strip punch. The solution of the integral equation of the contact problem is constructed by asymptotic methods with respect to the dimensionless parameter. The dependence of contact stresses on the...
-
Electronic structure and time-dependent description of rotational predissociation of LiH
PublicationThe adiabatic potential energy curves of the ^1Sigma+ and ^1Pi states of the LiH molecule were calculated. They correlate asymptotically to atomic states, such as 2s + 1s, 2p + 1s, 3s + 1s, 3p + 1s, 3d + 1s, 4s + 1s, 4p + 1s and 4d + 1s. A very good agreement was found between our calculated spectroscopic parameters and the experimental ones. The dynamics of the rotational predissociation process of the 1^1Pi state were studied...
-
Unusual streaming in chemically reacting gases
PublicationNonlinear stimulation of the vorticity mode caused by losses in the momentum of sound in the chemically reacting gas, is considered. The instantaneous dynamic equation which describes the nonlinear generation of the vorticity mode, is derived. It includes a quadratic nonlinear acoustic source. Both periodic and aperiodic sound may be considered as the origin of the vorticity flow. In the non-equilibrium regime of the chemical reaction,...
-
Nonlinear Interaction of Magnetoacoustic Modes in a Quasi-Isentropic Plasma Flow
PublicationThe nonlinear interaction of magnetoacoustic waves in a plasma is analytically studied. A plasma is an open system. It is affected by the straight constant equilibrium magnetic flux density forming constant angle with the wave vector which varies from 0 till . The nonlinear instantaneous equation which describes excitation of secondary wave modes in the field of intense magnetoacoustic perturbations is derived by use of projecting....
-
High-accuracy computation of hard X-ray focusing and imaging for refractive optics
PublicationA mathematical apparatus for solving problems of X-ray wave propagation through complex optical systems, when the lens thickness can change with jumps, is developed and presented. The developed method is based on the use of the superposition of oriented Gaussian beams, which satisfy the Helmholtz equation with high accuracy. The wave propagation in air and through kinoform and ordinary lenses is considered. Focusing and imaging...
-
GENERALISED HERSCHEL MODEL APPLIED TO BLOOD FLOW MODELLING
PublicationThis paper introduces a new rheological model of blood as a certain generalisation of the standard Herschel-Bulkley model. This model is a rheological constitutive equation and belongs to the group of the so-called generalised Newtonian fluids. Experimental data is compared with results, obtained from the new model, to demonstrate that it allows for the best agreement together with Luo-Kuang model. The new model may be easily implemented...
-
Systems, environments, and soliton rate equations: A non-Kolmogorovian framework for population dynamics
PublicationSoliton rate equations are based on non-Kolmogorovian models of probability and naturally include autocatalytic processes. The formalism is not widely known but has great unexplored potential for applications to systems interacting with environments. Beginning with links of contextuality to non- Kolmogorovity we introduce the general formalism of soliton rate equations and work out explicit examples of subsystems interacting with...
-
METHOD FOR SHIP'S ROLLING PERIOD PREDICTION WITH REGARD TO NON-LINEARITY OF GZ CURVE
PublicationThe paper deals with the problem of prediction of the rolling period. A special emphasis is put on the practical application of the new method for rolling period prediction with regard to non-linearity of the GZ curve. The one degree-of-freedom rolling equation is applied with using the non-linear stiffness moment and linear damping moment formulas. A number of ships are considered to research the discrepancies between the pending...
-
Control strategies and comparison of the Dynamic Voltage Restorer
PublicationThis paper focuses on a selection problems of mitigation of the voltage disturbance by of the Dynamic Voltage Restorers (DVR’s). In short form presented and discussed are the basis of different control strategies of the DVR. The main emphasis is placed on application of modern power electronic devices. Authors of this paper in particular occupy oneself with analysis of the power rating of the typically DVR topologies. These problems...
-
Performance of lubricated sliding contact in magnetic field
PublicationResults of experimental studies concerning theinfluence of permanent magnetic field on wear of lubricatedsliding contact operating at short stroke and highfrequency are presented. It was found that horizontalmagnetic is affecting performance of the contact. Thejagged delamination regions produced in the presence of amagnetic field can be regarded as easily undergoing oxidisationbecause oxygen is readily adsorbed there. Magneticfield...
-
"Ash" [æ] sound then and now: an overview of the current state of knowledge
PublicationThe objective of this article is to review the existing studies on the British Received Pronunciation “ash” [æ] sound, as well as its variations outside the United Kingdom. It starts with a short analysis of sociolinguistic aspects of the Received Pronunciation accent, then it points out the most conspicuous differences between the Received Pronunciation and General American vowel systems. Then, it presents the early beginnings...
-
Architecture and Basic Assumptions of RSMAD
PublicationThe study presents the architecture of Radio System for Monitoring and Acquisition of Data from Traffic Enforcement Cameras (in short RSMAD) which is used for transmission (realized using GSM, UMTS or TETRA networks, and through the Internet network), archiving and exploring image data of traffic offenses. The paper also presents selected basic assumptions of the RSMAD system, which are relevant to the implemented by the system...
-
Influence of magnetic field on wear in high frequency reciprocatingsliding contacts
PublicationResults of experimental studies concerning the influence of permanent magnetic field on wear of dry sliding contact operating at short stroke and high frequency are presented. It was found that horizontal magnetic field with different orientations relative to the sliding direction is affecting performance of the contact. The increase in frequency of sliding reduces accumulated mass loss and lowers the surface roughness of the wear...
-
Software modules and application layer's security structure of RSMAD
PublicationThe paper discusses the software modules of Radio System for Monitoring and Acquisition of Data from Traffic Enforcement Cameras (in short RSMAD). The structure of the application layer of the system has also been analysed in details, including: purpose, structure and principles of operation of software modules constituting this system. In addition, the paper presents and discusses the structure of security of application layer...
-
Determination of causes of accelerated local corrosion of austenitic steels in water supply systems
PublicationThis paper concerns an inspection of a water supply system, made of AISI 304 steel, which showed signs of local corrosion at the weld. Such corrosion caused material perforation after very short periods of operation. It was revealed that steel was sensitised during the welding process. It was also proven that chromium micro-segregation occurred in the alloy leading to galvanic cell formation which initialised the process of pitting...
-
Chirp-rate estimation of FM signals in the time-frequency domain
PublicationNovel dynamic representations of a complex signal in the time-frequency domain including: a channelized instantaneous complex frequency (CICF), a complex local group delay (CLGD) and a channelized instantaneous chirp-rate (CICR) are introduced. The proposed approach is based on the use of the gradient of the short-time Fourier transform complex phase. An interpretation of the newly-introduced distributions especially of the CICR...
-
The main developments of the CSR initiatives in Poland
PublicationThis short paper outlines the most important documents and initiatives that have appeared in the subject throughout the years within the international institutions, such as United Nations or European Union. It also discusses the ways in which the international CSR initiatives are being incorporated into Polish legislative and organizational system, by providing an outline of the biggest and most active organizations and foundations...
-
A study on signal processing methods applied to hearing aids
PublicationThis paper presents a short survey on current technology available in hearing aids with a focus on digital signal processing techniques used. First, factors influencing the hearing aid effectiveness are introduced. Then, examples of the present DSP methods and strategies are provided. Also, a description of current limitations of hearing aids and future trends of development are shown. Finally, the notion of computational auditory...
-
Methodology of Conformity Testing of VoIP Connections Scenarios for SIP Protocol
PublicationConformity and conformity testing have always had a crucial role in telecommunications. These issues are especially important in VoIP technology with SIP protocol as there are many hardware, software and service implementations. In this paper a methodology of automatic conformity testing of VoIP connections scenarios applying to any IP network is proposed. Example implementation of the methodology as Linux shell scripts is presented....
-
Musical Instrument Separation Applied to Music Genre Classification . Separacja instrumentów muzycznych w zastosowaniu do rozpoznawania gatunków muzycznych
PublicationThis paper outlines first issues related to music genre classification and a short description of algorithms used for musical instrument separation. Also, the paper presents proposed optimization of the feature vectors used for music genre recognition. Then, the ability of decision algorithms to properly recognize music genres is discussed based on two databases. In addition, results are cited for another database with regard to...
-
Acceleration of decision making in sound event recognition employing supercomputing cluster
PublicationParallel processing of audio data streams is introduced to shorten the decision making time in hazardous sound event recognition. A supercomputing cluster environment with a framework dedicated to processing multimedia data streams in real time is used. The sound event recognition algorithms employed are based on detecting foreground events, calculating their features in short time frames, and classifying the events with Support...
-
Ocena wpływu drgań przekazywanych na budynek przez agregat prądotwórczy
PublicationW artykule opisano zakres badań polowych niezbędnych do określenia poziomu drgań w budynku biurowo-usługowym podczas pracy agregatu prądotwórczego zlokalizowanego na dachu tego budynku. Dokonano oceny szkodliwości pomierzonych drgań na budynek i ludzi, którzy się w nim znajdują. Przedstawiono także krótki przegląd literatury dotyczącej oceny szkodliwości oddziaływań dynamicznych na budynki lub ludzi.
-
Operational Performance and Weld Bead Characteristics of Experimental Tubular-Wires for Underwater Welding
PublicationAiming to evaluate new formulations and their operational behavior underwater, two experimental tubular wires with different chemical compositions in their internal flux were initially manufactured, employing a pilot machine and a unique manufacturing process. Weld beads were deposited on a plate placed in a flat position inside a tank using a mechanized system and the IMC 300 welding power source. The work was done at a depth...
-
Sex contribution to average age at onset of Huntington's disease depends on the number of (CAG)n repeats
PublicationHuntington’s disease (HD) is a hereditary neurodegenerative disorder caused by the extension of the CAG repeats in exon 1 of the HTT gene and is transmitted in a dominant manner. The present study aimed to assess whether patients’ sex, in the context of mutated and normal allele length, contributes to age on onset (AO) of HD. The study population comprised a large cohort of 3723 HD patients from the European Huntington’s Disease...
-
Prognozowanie właściwości złączy spawanych pod wodą metodą lokalnej komory suchej
PublicationNiniejsza praca jest poświęcona spawaniu pod wodą metodą lokalnej komory suchej (MLKS) i przedstawia metodologię oraz narzędzia umożliwiające prognozowanie właściwości złączy spawanych wykonanych przy zastosowaniu tej odmiany spawania. Monografia zawiera opis rozwoju spawania pod wodą oraz charakterystykę metod wykorzystywanych do realizacji prac spawalniczych. Zaproponowano nowy podział metod spawania pod wodą, uwzględniający...
-
Diploma Seminar (PG_00042079) D&PE 2023 Winter Semester
e-Learning CoursesPresentation of the topic, the main issues of the diploma thesis and the tasks of the diploma thesis completed so far. The topic of the presentation is the same as the topic of the diploma thesis. Presentation of a literature analysis, including, among others: 10 papers from journals related to the topic of the work. Submitting to e-learning platform: - pdf version of the presentation - printed description (max 4 pages) a of the...
-
Distortional buckling of composite thin-walled columns of a box-type cross section with diaphragms
PublicationDistortional buckling of axially compressed columns of box-like composite cross sections with andwithout internal diaphragms is investigated in the framework of one-dimensional theory. The channel membersare composed of unidirectional fibre-reinforced laminate. Two approaches to the member orthotropic materialare applied: homogenization based on the theory of mixture and periodicity cells, and homogenization basedon the Voigt–Reuss...
-
Different sources of market information and product innovativeness
PublicationThe purpose of this study is to identify whether the gathering of market information from different sources – i.e. from customers, competitors and other entities – is related to product innovativeness. The relationships proposed so far have not been empirically investigated but they can have important theoretical and practical implications for product innovation. To achieve the purpose of the paper data concerning 287 new products...
-
Modelling the malware propagation in mobile computer devices
PublicationNowadays malware is a major threat to the security of cyber activities. The rapid develop- ment of the Internet and the progressive implementation of the Internet of Things (IoT) increase the security needs of networks. This research presents a theoretical model of malware propagation for mobile computer devices. It is based on the susceptible-exposed- infected-recovered-susceptible (SEIRS) epidemic model. The scheme is based on...