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New hybrid quadrature schemes for weakly singular kernels applied to isogeometric boundary elements for 3D Stokes flow
PublikacjaThis work proposes four novel hybrid quadrature schemes for the efficient and accurate evaluation of weakly singular boundary integrals (1/r kernel) on arbitrary smooth surfaces. Such integrals appear in boundary element analysis for several partial differential equations including the Stokes equation for viscous flow and the Helmholtz equation for acoustics. The proposed quadrature schemes apply a Duffy transform-based quadrature...
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Jednoelektronowy atom Diraca w słabym polu magnetycznym
PublikacjaW rozprawie przedstawiono opis wpływu zewnętrznego stałego, słabego, jednorodnego pola magnetycznego na jednoelektronowy atom Diraca. Wykorzystując funkcje gęstości ładunku elektrycznego oraz gęstości prądu elektrycznego, rozważono procesy indukowania się w atomie dodatkowych elektromagnetycznych momentów multipolowych. Dokonano analizy indukowanego momentu dipolowego, w wyniku której uzyskano wyrażenie dla magnetyzowalności atomu....
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Communication: Inside the water wheel: Intrinsic differences between hydrated tetraphenylphosphonium and tetraphenylborate ions
PublikacjaTetraphenylphosphonium tetraphenylborate (TPTB) is a common reference electrolyte in physical chemistry of solutions allowing for a convenient partitioning of thermodynamic properties into single-ion contributions. Here, we compute on the basis of ab initio molecular dynamics simulations the infrared (IR) spectra for hydrated constituent ions of the TPTB assumption. Using spectral decomposition techniques, we extract important...
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Systems, Environments, and Soliton Rate Equations: Toward Realistic Modeling
PublikacjaIn order to solve a system of nonlinear rate equations one can try to use some soliton methods. The procedure involves three steps: (1) find a ‘Lax representation’ where all the kinetic variables are combined into a single matrix ρ, all the kinetic constants are encoded in a matrix H; (2) find a Darboux–Bäcklund dressing transformation for the Lax representation iρ˙=[H,f(ρ)], where f models a time-dependent environment; (3) find...
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Scheduling with Complete Multipartite Incompatibility Graph on Parallel Machines: Complexity and Algorithms
PublikacjaIn this paper, the problem of scheduling on parallel machines with a presence of incompatibilities between jobs is considered. The incompatibility relation can be modeled as a complete multipartite graph in which each edge denotes a pair of jobs that cannot be scheduled on the same machine. The paper provides several results concerning schedules, optimal or approximate with respect to the two most popular criteria of optimality:...
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Material Parameters Identification of Historic Lighthouse Based on Operational Modal Analysis
PublikacjaIn the present paper, the identification of the material parameters of a masonry lighthouse is discussed. A fully non-invasive method was selected, in which the material properties were determined via numerical model validation applied to the first pair of natural frequencies and their related mode shapes, determined experimentally. The exact structural model was built by means of the finite element method. To obtain experimental...
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INVESTIGATION OF THE EFFECT OF THE ROCKET'S SUBORBITAL FLIGHT ON BIOFILM, ENZYMES AND BIOSYNTHESIS ON AUTONOMOUS, MODULAR AND SCALABLE PLATFORM FOR CONDUCTING EXPERIMENTS OF AN ASTROBIOTECHNOLOGICAL NATURE
PublikacjaWith new incentives for human space exploration, biotechnological experiments in orbit became imperative.Answering this need, we build an autonomous, modular, and scalable platform that enables those experiments onrockets. We called it AMBER. The aim of the payload of the R6 suborbital rocket is to perform an experiment tostudy the influence of rocket flights on biofilm, molecular...
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Evaluation of citric acid corrosion inhibition efficiency and passivation kinetics for aluminium alloys in alkaline media by means of dynamic impedance monitoring
PublikacjaA novel approach is proposed for constructing the adsorption isotherm in corrosion studies, based on a well-known interaction between citric acid and aluminium in alkaline electrolytes. Our approach utilizes the instantaneous impedance measurements via Dynamic Electrochemical Impedance Spectroscopy in galvanostatic mode (g-DEIS). Unlike other common tools, g-DEIS delivers exact information about the concentration required for full...
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Size-exclusion chromatography for the determination of the boiling point distribution of high-boiling petroleum fractions
PublikacjaThe paper describes a new procedure for the determination of boiling point distribution of high-boiling petroleum fractions using size exclusion chromatography with refractive index detector. Thus far, the determination of boiling range distribution by chromatography has been accomplished using simulated distillation with gas chromatography with the flame ionization detection. This study revealed that in spite of substantial differences...
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Optical profilometer
PublikacjaThe profilometry plays a huge role in the most fields of science and technology. It allows to measure the profile of the surface with high-resolution. This technique is used in the fields like optic, electronic, medicine, automotive, and much more. The aim of the current work was to design and build optical profilometer based on the interference phenomena. The developed device has been working with He-Ne laser (632.8 nm). The optical...
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MicroGal Gravity Measurements with MGS-6 Micro-g LaCoste Gravimeter
PublikacjaKnowing the exact number of fruit and trees helps growers to make better decisions about how to manage their production in the orchard and prevent plant diseases. The current practice of yield estimation is to manually count fruit or flowers (before harvesting), which is a very time-consuming and costly process. Moreover it’s not practical for large orchards. It also doesn’t allow to make predictions of plant development in a more...
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Estimates for minimal number of periodic points for smooth self-maps of simply-connected manifolds
Dane BadawczeWe consider a closed smooth connected and simply-connected manifold of dimension at least 4 and its self-map f. The topological invariant Dr[f] is equal to the minimal number of r-periodic points in the smooth homotopy class of f. We assume that r is odd and all coefficients b(k) of so-called periodic expansion of Lefschetz numbers of iterations are...
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Certified domination
PublikacjaImagine that we are given a set D of officials and a set W of civils. For each civil x ∈ W, there must be an official v ∈ D that can serve x, and whenever any such v is serving x, there must also be another civil w ∈ W that observes v, that is, w may act as a kind of witness, to avoid any abuse from v. What is the minimum number of officials to guarantee such a service, assuming a given social network? In this paper, we introduce...
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Pose-Configurable Generic Tracking of Elongated Objects
PublikacjaElongated objects have various shapes and can shift, rotate, change scale, and be rigid or deform by flexing, articulating, and vibrating, with examples as varied as a glass bottle, a robotic arm, a surgical suture, a finger pair, a tram, and a guitar string. This generally makes tracking of poses of elongated objects very challenging. We describe a unified, configurable framework for tracking the pose of elongated objects, which...
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Co-simulation strategy of transient CFD and heat transfer in building thermal envelope based on calibrated heat transfer coefficients
PublikacjaThe paper presents a strategy to develop a fully transient numerical model of a heat transfer in building, using a transient CFD model of indoor air and a thermal envelope model, running in a co-simulation. The strategy relies on the utilization of RANS with a high-Re turbulence model and a wall function, which enables to use a coarse computational mesh limiting the computational time. Since wall functions give invalid heat transfer...
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Collision-Free Network Exploration
PublikacjaA set of mobile agents is placed at different nodes of a n-node network. The agents synchronously move along the network edges in a collision-free way, i.e., in no round may two agents occupy the same node. In each round, an agent may choose to stay at its currently occupied node or to move to one of its neighbors. An agent has no knowledge of the number and initial positions of other agents. We are looking for the shortest possible...
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Error analysis of calculating average d-q current components using Regular Sampling and Park transformation in FOC drives
PublikacjaIn electric drives using voltage source inverters, motor currents contain ripple component resulting from pulse-width modulated (PWM) voltage. The frequency range of the ripples is much higher than the bandwidth of current control. Therefore the control is performed on the basis of a fundamental current component, i.e. average value with the averaging time being the PWM period. In majority of cases the average current is measured...
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The In-House Method of Manufacturing a Low-Cost Heat Pipe with Specified Thermophysical Properties and Geometry
PublikacjaVarious types of heat pipes are available to purchase off the shelf, from various manufacturers, but most of them have strictly defined geometry and technical parameters. However, when there is a need to use a heat pipe (HP) with an unusual size and shape or working conditions other than the standard ones, it becomes very costly to order them from manufacturers, especially in small quantities, and only a few producers are willing...
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Analytical applications of smartphones for agricultural soil analysis
PublikacjaSoil is one of the most important farming resources. Appropriate managing of its quality promotes productive and sustainable agriculture. The valuable farm practice in soil quality managing is based on regular soil analysis with the aim to determine the exact amount of nutrients or other chemical, physical and biological soil properties. Soil analysis usually requires samples collection at desired sampling depth following by samples...
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Database of the convergence analysis results of the nonstandard approximation of the generalized Burgers–Huxley equation for the solution bounded within [0,1].
Dane BadawczeThe presented dataset is a result of the convergence analysis of the Mickens-type, nonlinear, finite-difference discretization of a generalized Burgers–Huxley partial differential equation.
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Database of the convergence analysis results of the nonstandard approximation of the generalized Burgers–Huxley equation for the solution bounded within [0, γ^(1/p)].
Dane BadawczePresented dataset is a result of the convergence analysis of the Mickens-type, nonlinear, finite-difference discretization of a generalized Burgers–Huxley partial differential equation. The generalized Burgers–Huxley equation is a diffusive partial differential equation with nonlinear advection and diffusion. The boundary problem for this equation possesses...
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Anna Wałek dr
OsobyDr Anna Wałek, Prezydent International Association of University Libraries (IATUL), dyrektor Biblioteki Politechniki Gdańskiej, ekspert w zakresie otwartego dostępu do zasobów naukowych (Open Science, Open Access, Open Research Data) oraz organizacji i zarządzania biblioteką naukową. Od lutego 2023 r. ekspert i Koordynator Hubu Wschodniego (East Hub) w ramach projektu Focusing on Open, Collaboration and Useful Science (EOSC Focus)...
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Analysis of Organic Rankine Cycle efficiency and vapor generator heat transfer surface in function of the reduced pressure
PublikacjaIn the paper presented is analysis of the influence of reduced pressure on efficiency and heat transfer area of vapor generator of Organic Rankine Cycle (ORC) in case of subcritical and supercritical parameters of operation. Compared are two cases of subcritical and supercritical ORC featuring a similar arrangement of heat source supply and heat removal, that is featuring the same temperatures of working fluid before the turbine,...
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Detecting Apples in the Wild: Potential for Harvest Quantity Estimation
PublikacjaKnowing the exact number of fruits and trees helps farmers to make better decisions in their orchard production management. The current practice of crop estimation practice often involves manual counting of fruits (before harvesting), which is an extremely time-consuming and costly process. Additionally, this is not practicable for large orchards. Thanks to the changes that have taken place in recent years in the field of image...
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Nonlinear control of five phase induction motor with synchronized third harmonic flux injection
PublikacjaThe paper deals with the novel control system for five phase induction motor (IM) that enables the injection of the rotor flux 3rd harmonic component. Two multiscalar models are transformed from the 1-1 and 2-2 vector models developed in the 1st and 3rd harmonic planes. Based on the obtained multiscalar models the synthesis of dual multiscalar control is established. The obtained two multiscalar control systems can independently...
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Value of Age Diversity – Declarations and Practice in Polish Organizations
PublikacjaThe present article relates to management of age diverse teams in organisations and enterprises located in Poland. Managing diversity is an active and conscious process leading not only to a lack of discriminatory conduct but above all to making full use of the potential of the team. The potential resulting from the diversity of knowledge, skills and experience. The diversity of the age of the team members is in fact a differentiation...
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Innovative activity of SMEs In Poland
PublikacjaInnovative activity of enterprises is determined by many factors. On one hand, these are external factors creating a sort of innovative climate in the economy, on the other hand - there are many internal factors stimulating or reducing the intensity of innovative activities. What influences the innovativeness of enterprises is the effectiveness of the system supporting innovations, which was stated by for example Pyciński and Żołnierski...
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Molecular basis of the osmolyte effect on protein stability: a lesson from the mechanical unfolding of lysozyme
PublikacjaOsmolytes are a class of small organic molecules that shift the protein folding equilibrium. For this reason, they are accumulated by organisms under environmental stress, and find applications in biotechnology where proteins need to be stabilized or dissolved. However, despite years of research, debate continues over the exact mechanisms underpinning the stabilizing and denaturing effect of osmolytes. Here, we simulated the mechanical...
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Static electric and magnetic multipole susceptibilities for Dirac one-electron atoms in the ground state
PublikacjaWe present tabulated data for several families of static electric and magnetic multipole susceptibilities for hydrogenic atoms with nuclear charge numbers from the range $1\leq Z\leq137$. Atomic nuclei are assumed to be point-like and spinless. The susceptibilities considered include the multipole electric polarizabilities $\alpha_{\mathrm{E}L\to\mathrm{E}L}$ and magnetizabilities (magnetic susceptibilities) $\chi_{\mathrm{M}L\to\mathrm{M}L}$...
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Hydrophobic and hydrophilic properties of pollutants as a factor influencing their redistribution during snowpack melt
PublikacjaGlaciers accumulate organic pollutants delivered by snow. However, our understanding of the exact dynamics of organic pollutants in the snowpack relies primarily on laboratory experiments and mathematical models. To fill the gap related to the detailed field data, we have conducted observations of melting snow profiles in two locations and three different stages of melting on one High Arctic glacier, as well as in superimposed...
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Approximation algorithms for job scheduling with block-type conflict graphs
PublikacjaThe problem of scheduling jobs on parallel machines (identical, uniform, or unrelated), under incompatibility relation modeled as a block graph, under the makespan optimality criterion, is considered in this paper. No two jobs that are in the relation (equivalently in the same block) may be scheduled on the same machine in this model. The presented model stems from a well-established line of research combining scheduling theory...
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Time fractional analysis of Casson fluid with application of novel hybrid fractional derivative operator
PublikacjaA new approach is used to investigate the analytical solutions of the mathematical fractional Casson fluid model that is described by the Constant Proportional Caputo fractional operator having non-local and singular kernel near an infinitely vertical plate. The phenomenon has been expressed in terms of partial differential equations, and the governing equations were then transformed in non-dimensional form. For the sake of generalized...
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High frequency oscillations in human memory and cognition: a neurophysiological substrate of engrams?
PublikacjaDespite advances in understanding the cellular and molecular processes underlying memory and cognition, and recent successful modulation of cognitive performance in brain disorders, the neurophysiological mechanisms remain underexplored. High frequency oscillations beyond the classic electroencephalogram spectrum have emerged as a potential neural correlate of fundamental cognitive processes. High frequency oscillations are detected...
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Analiza porównawcza metod zwiększania nośności i sztywności stalowych, doczołowych węzłów śrubowych.
PublikacjaInnowacyjna, w porównaniu z dotychczas stosowanym sposobem, metoda obliczania nośności stalowych węzłów została wdrożona wraz z normami europejskimi. Pozwala ona dokładniej odwzo-rować rzeczywistą pracę poszczególnych części węzła, gdyż wynik obliczeń uzależniony jest od znacznie większej liczby zmiennych. Dzięki postępowi technologicznemu w zakresie metalurgii oraz badaniom naukowym obecnie możliwe jest wzmacnianie połączeń...
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Marcin Wekwejt dr inż.
OsobyMarcin Wekwejt, absolwent studiów inżynierskich w inż. biomedycznej (2016; Politechnika Bydgoska im. J. i J. Śniadeckich & Collegium Medicum im. L. Rydygiera), studiów magisterskich w inż. mechaniczno-medycznej (2018; Politechnika Gdańska & Gdański Uniwersytet Medyczny) oraz studiów doktoranckich w dyscyplinie inż. materiałowej (2021, Politechnika Gdańska). Uzyskał z wyróżnieniem stopień naukowy doktora nauk inżynieryjno-technicznych...
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Molecular level interpretation of excess infrared spectroscopy
PublikacjaInfrared (IR) spectroscopy is an invaluable tool in studying intermolecular interactions in solvent mixtures. The deviation of the IR spectrum of a mixture from the spectra of its pure components is a sensitive measure of the non-ideality of solutions and the modulation of intermolecular interactions introduced by mutual influence of the components. Excess IR spectroscopy, based on the established notion of excess thermodynamic...
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Interactions in aqueous solutions of K-peptide and DMSO – spectroscopic and calorimetric studies
PublikacjaIntroduction K-peptide (GILQINSRW) – short 9 amino acid fragment of the hen egg white lysozyme has the ability to form amyloid structures. Dimethyl sulfoxide (DMSO) is an osmolyte which can alter this ability. Our goal was to get an insight into the mechanism of Kpeptide-DMSO interactions in aqueous solutions. Such a knowledge can be helpful to understand processes leading to various neurodegenerative diseases. Methods ATR-FTIR...
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More Than just Antioxidants: Redox-Active Components and Mechanisms Shaping Redox Signalling Network
PublikacjasettingsOrder Article Reprints This is an early access version, the complete PDF, HTML, and XML versions will be available soon. Open AccessReview More Than just Antioxidants: Redox-Active Components and Mechanisms Shaping Redox Signalling Network by Monika Kuczyńska,Patrycja Jakubek andAgnieszka Bartoszek *ORCID Faculty of Chemistry, Gdańsk University of Technology, 80-233 Gdańsk, Poland * Author to whom correspondence should...
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Phytoecdysteroid containing plants – a source of bioactive compounds with potential anticarcinogenic effects
PublikacjaEcdysteroids are a group of steroids synthesized in inver- tebrates as molting hormones and also in some plants as secondary metabolites acting as a defense against parasites. These compounds do not naturally occur in mammals and are not structurally related to mammalian steroid hor- mones, consequently do not activate mammalian hormone receptors. Ecdysteroids exhibit very low toxicity to mam- mals and to date no serious side effects...
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The ONETEP linear-scaling density functional theory program
PublikacjaWe present an overview of the ONETEP program for linear-scaling density functional theory (DFT) calculations with large basis set (planewave) accuracy on parallel computers. The DFT energy is computed from the density matrix, which is constructed from spatially localized orbitals we call Non-orthogonal Generalized Wannier Functions (NGWFs), expressed in terms of periodic sinc (psinc) functions. During the calculation, both the...
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Analytical progress on symmetric geometric discord: Measurement-based upper bounds
PublikacjaQuantum correlations may be measured by means of the distance of the state to the subclass ofstates having well defined classical properties. In particular, a geometric measure of asymmetricdiscord [Daki´c et al., Phys. Rev. Lett. 105, 190502 (2010)] was recently defined as the Hilbert-Schmidt distance of a given two-qubit state to the closest classical-quantum (CQ) correlated state.We analyze a geometric measure of symmetric...
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Spatio-Temporal Validation of GNSS-Derived Global Ionosphere Maps Using 16 Years of Jason Satellites Observations
PublikacjaExisting ionospheric models perform very well in mapping the calm state of the ionosphere. However, the problem is accurately determining the total electron content (TEC) for disturbed days. Knowledge of the exact electron density is essential for single−frequency receivers, which cannot eliminate the ionospheric delay. This study aims to investigate temporal and spatial variability in the distribution of TEC based on differences...
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Accuracy of Pretreatment Ultrasonography Assessment of Intra-Abdominal Spread in Epithelial Ovarian Cancer: A Prospective Study
PublikacjaThe aim of this study was to test the accuracy of ultrasonography performed by gynecological oncologists for the preoperative assessment of epithelial ovarian cancer (EOC) spread in the pelvis and abdominal cavity. A prospective, observational cohort study was performed at a single tertiary cancer care unit. Patients with suspected EOC were recruited and underwent comprehensive transvaginal and abdominal ultrasonography performed...
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Remarks on use of the term “deep eutectic solvent” in analytical chemistry
PublikacjaAbout 20 years ago, Abbott and co-workers researched new solvents that were based on mixtures of choline chloride with urea and carboxylic acids and that were liquid at ambient temperature. The term “deep eutectic solvent” (DES) was later adopted for similar mixtures. As DESs have a number of interesting features, they quickly attracted the attention of researchers and found application in various branches of chemical and materials...
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Global defensive secure structures
PublikacjaLet S ⊂ V (G) for a given simple non-empty graph G. We define for any nonempty subset X of S the predicate SECG,S(X) = true iff |NG[X]∩S| ≥ |NG[X]\S|. Let H be a non-empty family of graphs such that for each vertex v ∈ V (G) there is a subgraph H of G containing v and isomorphic to a member of H. We introduce the concept of H-alliance extending the concept of global defensive secure structures. By an H-alliance in a graph G we...
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The forecasts-based instrument rule and decision making. How closely interlinked? The case of Sweden
PublikacjaResearch background: The Central Bank of Sweden declared in years 1999–2006 the implementation of the Svensson’s concept of inflation forecast targeting (IFT). It means that the repo rate decision-making process depends on the inflation forecasts. The concept evolved from the strict IFT with the decision-making algorithm called ‘the rule of thumb’ to the flexible IFT. Purpose of the article: The aim of...
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Ultrasound and Clinical Preoperative Characteristics for Discrimination Between Ovarian Metastatic Colorectal Cancer and Primary Ovarian Cancer: A Case-Control Study
PublikacjaThe aim of this study was to describe the clinical and sonographic features of ovarian metastases originating from colorectal cancer (mCRC), and to discriminate mCRC from primary ovarian cancer (OC). We conducted a multi-institutional, retrospective study of consecutive patients with ovarian mCRC who had undergone ultrasound examination using the International Ovarian Tumor Analysis (IOTA) terminology, with the addition of evaluating...
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Improving methods to calculate the loss of ecosystem services provided by urban trees using LiDAR and aerial orthophotos
PublikacjaIn this paper we propose a methodology for combining remotely sensed data with field measurements to assess selected tree parameters (diameter at breast height (DBH) and tree species) required by the i-Tree Eco model to estimate ecosystem services (ES) provided by urban trees. We determined values of ES provided by trees in 2017 in Racibórz (a city in South Poland) and estimated the loss of ES from January 1, 2017 to March 5, 2017,...
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Vident-synth: a synthetic intra-oral video dataset for optical flow estimation
Dane BadawczeWe introduce Vident-synth, a large dataset of synthetic dental videos with corresponding ground truth forward and backward optical flows and occlusion masks. It can be used for:
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Kinga Kaniewska-Laskowska dr inż.
OsobyWykształcenie Studia I stopnia - inżynierskie, kierunek CHEMIA 2013: Politechnika Gdańska, Wydział Chemiczny, Katedra Chemii Nieorganicznej Tytuł pracy inżynierskiej: „Kompleksy żelaza z ligandami fosfinidenowymi” Promotor: dr hab. inż. Rafał Grubba Studia II stopnia - magisterskie, kierunek TECHNOLOGIA CHEMICZNA, spec. Technologia Organiczna 2014: Politechnika Gdańska, Wydział Chemiczny, Katedra Chemii Nieorganicznej Tytuł pracy...