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Biocompatibility and Bioactivity of Load-Bearing Metallic Implants
PublikacjaThe main objective of here presented research is to develop the titanium (Ti) alloy base composite materials possessing better biocompatibility, longer lifetime and bioactivity behaviour for load-bearing implants, e.g. hip joint and knee joint endoprosthesis. The development of such materials is performed through: modeling the material behaviour in biological environment in long time and developing of new procedures for such evaluation;...
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A role of the heat and work uncompensatedtransformations in the balance of entropy and theturbomachinery efficiency
PublikacjaIn the paper we have presented a procedure of estimating a role of the uncompensated transformation of heat and work in ow of viscous and heat conducting uid. The procedure was introduced by Professor Romuald Puzyrewski and is essential in local, in time and space, balance of entropy. Furthermore this unique approach leads to redenition the eciency of uid-ow machinery in three-dimensional modeling using CFD (Computational Fluid...
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Possibilities of radioisotope measuring in control of an unstable solid particles hydrotransport
PublikacjaThe paper presents γ-radiation proposal to control a multiphase flow, independently from circumstances. So this method may be applied even in compound industrial or environmental processes. Moreover in many cases, it is the only method for applications for dense mixture containing coarse angular grains. The constructed equipment allows continuous measurement of density as well as solid phase for both concentration and average velocity....
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Experimental certification of an informationally complete quantum measurement in a device-independent protocol
PublikacjaMinimal informationally complete positive operator-valued measures (MIC-POVMs) are special kinds of measurement in quantum theory in which the statistics of their d2-outcomes are enough to reconstruct any d-dimensional quantum state. For this reason, MIC-POVMs are referred to as standard measurements for quantum information.Here, we report an experiment with entangled photon pairs that certifies, for what we believe is the first...
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Lax-Wendroff and McCormack Schemes for Numerical Simulation of Unsteady Gradually and Rapidly Varied Open Channel Flow
PublikacjaTwo explicit schemes of the finite difference method are presented and analyzed in the paper. The applicability of the Lax-Wendroff and McCormack schemes for modeling unsteady rapidly and gradually varied open channel flow is investigated. For simulation of the transcritical flow the original and improved McCormack scheme is used. The schemes are used for numerical solution of one dimensional Saint-Venant equations describing free...
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New data acquisition system for birch sap concentrate production using the reverse osmosis technology
PublikacjaThe work presents a simple electronic device that helps to monitor the basic parameters of the reverse osmosis (RO) system during the concentration of birch tree sap. The construction costs are low (around 150 Euro) but the functionality of the device is high. It has an in-build two channel conductometer and can measure the volumetric flow rate of two streams of liquids. The collected data are transmitted wirelessly via Bluetooth...
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Modelling of Objects Behaviour for Their Re-identification in Multi-camera Surveillance System Employing Particle Filters and Flow Graphs
PublikacjaAn extension of the re-identification method of modeling objects behavior in muti-camera surveillance systems, related to adding a particle filter to the decision-making algorithm is covered by the paper. A variety of tracking methods related to a single FOV (Field of Vision) are known, proven to be quite different for inter-camera tracking, especially in case of non-overlapping FOVs. The re-identification methods refer to the...
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Hydrodynamic reanalysis of sea level in the Baltic Sea using the PM3D model
Dane BadawczeThe data set contains the results of numerical modelling of sea level fluctuations in the Baltic Sea in the Baltic Sea since 1998. A long-term reanalysis was performed using a three-dimensional hydrodynamic model PM3D (Kowalewski and Kowalewska-Kalkowska, 2017), a new version of the M3D model (Kowalewski, 1997).
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Analiza nośności zabytkowych fundamentów w kontekście jakości użytych zapraw Analysis of the Load-Bearing Capacity of Historical Foundations in the Context of the Quality of Mortar Used
PublikacjaStructures of historical buildings usually have the form of masonry elements. The weakest component of such elements is mortar, especially in stone foundations, which were often used in the with a focus on the modeling of mortar as a joint connecting stones in a characteristic medieval foundation. Different types of mortar: cement, cement-lime, lime and gypsum mortars, were examined. A numerical analysis was carried out on the...
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Numerical analysis of open channel steady gradually varied flow using the simplified saint-venant equations
PublikacjaFor one-dimensional open-channel flow modeling, the energy equation is usually used. There exist numerous approaches using the energy equation for open-channel flow computations, which resulted in the development of several very efficient methods for solving this problem applied to channel networks. However, the dynamic equation can be used for this purpose as well. This paper introduces a method for solving a system of non-linear...
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Analytical method of determining dynamic properties of thermocouples used in measurements of quick – changing temperatures of exhaust gases in marine diesel engines
PublikacjaThe article presents selected issues of mathematical modeling of heat exchange between the thermocouple and the exhaust gas flowing them, in unsteady conditions. On the way of energy balancing consideration of thermodynamic processes developed differential equations describing the dynamic properties for three versions of the design sheathed thermocouples: with weld isolated from the sheath, with weld welded the sheath and with...
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The comparison of vodka, whisky and moonshine by using the electronic nose based on the technology of ultra-fast gas chromatography
PublikacjaVodka andwhisky are produced fromgrain distillates. Formerly these alcohols were very often counterfeited, by the made in home conditions spirit drink called moonshine, which is obtained by distilling a mash from the alcoholic fermentation. This study presents research aimed at checking the usefulness of the electronic nose using ultra-fast gas chromatography for the differentiation of whisky, vodka and moonshine. 12 samples of...
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The comparison of vodka, whisky and moonshine by using the electronic nose based on the technology of ultra-fast gas chromatography
PublikacjaVodka andwhisky are produced fromgrain distillates. Formerly these alcohols were very often counterfeited, by the made in home conditions spirit drink called moonshine, which is obtained by distilling a mash from the alcoholic fermentation. This study presents research aimed at checking the usefulness of the electronic nose using ultra-fast gas chromatography for the differentiation of whisky, vodka and moonshine. 12 samples of...
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Evaluation of Workflow Runtime Platforms in Service Composition
PublikacjaTypically, workflow applications are constructed from basic functionalities that may be realized by alternative services deployed in heterogeneous runtime platforms. Depending on workflow structure and selection of services, the applications differ in attributes such as price, Quality of Service (QoS) and others. In the paper, we propose a method of evaluation of workflow runtime platforms using Data Envelopment Analysis. We present...
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Special Issue: “Non-Destructive Testing of Structures”
PublikacjaThe Special Issue “Non-Destructive Testing of Structures” has been proposed to present recent developments in the field of diagnostics of structural materials and components in civil and mechanical engineering. The papers highlighted in this editorial concern various aspects of non-invasive diagnostics, including such topics as condition assessments of civil and mechanical structures and connections of structural elements, the...
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RNDM 2016 Workshop and 2nd Meeting of COST CA15127-RECODIS: Highlights from the Resilience Week in Halmstad, Sweden
PublikacjaLeading network resilience researchers took part in the Resilience Week on Sept. 12-15, 2016 at Halmstad University, SE by Prof. Magnus Jonsson from the Centre for Research on Embedded Systems (CERES), Halmstad University, SE, and Prof. Jacek Rak from Gdansk University of Technology, PL. It included two major events: - The 2nd Meeting of COST CA15127–RECODIS Action (Resilient Communication Services Protecting End-user Applications...
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Koncepcja i modelowanie silnika o wirującym tworniku oraz magneśnicy do zastosowania w napędzie miejskiego samochodu elektrycznego
PublikacjaW artykule zaprezentowano koncepcję, model oraz prototyp silnika z wirującym twornikiem oraz magneśnicą. Opisano historię powstania i zastosowania tego typu silników w motoryzacji. Przedstawiono nowoczesne rozwiązania konstrukcyjne i zastosowania we współczesnych samochodach elektrycznych i hybrydowych. Opracowano model silnika z wirującym twornikiem i magneśnicą oraz przedstawiono wybrane wyniki symulacji przeprowadzone w programie...
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Określenie parametrów modelowania geometrii krzyżownic rozjazdów zwyczajnych dla potrzeb budowy i utrzymania linii kolejowych
PublikacjaZdecydowana większość rozjazdów występująca na liniach kolejowych w Polsce to rozjazdy zwyczajne o typowym zestawie parametrów. Z tego powodu analiza przypadków nietypowych (takich jak rozjazdy o zmiennej krzywiźnie toru zwrotnego) może być utrudniona. Wirtualny model geometryczno-konstrukcyjny rozjazdu, generowany w oparciu o metody analityczne, stanowić może narzędzie użyteczne w sferze projektowania, konstrukcji oraz diagnostyki...
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Analiza czynników wpływających na prędkość pojazdów transportu zbiorowego na przykładzie Gdańska
PublikacjaW referacie przedstawiono istotę problemu szacowania prędkości pojazdów transportu zbiorowego w szczególności w zakresie modelowania ruchu. Przedstawiono i omówiono wyniki przeprowadzonych w maju ubiegłego roku pomiarów czasu przejazdu pojazdów transportu zbiorowego na obszarze Gdańska w ramach budowy systemu sterowania ruchem TRISTAR. Otrzymane wyniki zestawiono w celu zaprezentowania statystyki oraz zidentyfikowania czynników...
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Closed Form Constraint Equations Used to Express Frictionless Slip of Multibody Systems Attached to Finite Elements—Application to a Contact between a Double Pendulum and a Beam
PublikacjaThis paper focuses on the numerical modeling of the dynamics of mechanical systems. Robots that can inspect high-voltage lines inspired this research. Their control systems must anticipate potential grab positions appropriately. We intend to formulate equations dedicated to the numerical description of the robot/cable contact. The investigated problem is not straightforward, since parts of the modeled systems are numerically inhomogeneous....
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Machine Learning-Based Wetland Vulnerability Assessment in the Sindh Province Ramsar Site Using Remote Sensing Data
PublikacjaWetlands provide vital ecological and socioeconomic services but face escalating pressures worldwide. This study undertakes an integrated spatiotemporal assessment of the multifaceted vulnerabilities shaping Khinjhir Lake, an ecologically significant wetland ecosystem in Pakistan, using advanced geospatial and machine learning techniques. Multi-temporal optical remote sensing data from 2000 to 2020 was analyzed through spectral...
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An integrated framework for security protocol analysis
PublikacjaAssurance of security protocols needs particular attention. Flaws in a protocol can devastate security of the applications that rely on it. Analysis of the protocols is difficult and it is recommended that formal methods are employed to provide for higher levels of assurance. However, the formal methods can cover only a part of the scope of the problem. It is important that the formal models are valid representations of the protocol...
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Experiments and Analysis of the Limit Stresses of a Magnetorheological Fluid
PublikacjaPaper presents the results of a rheological test of a commercial magnetorheological (MR) fluid (MRF-132DG). The researchincludes the problem of measuring and interpreting limit stresses under conditions close to the magnetic saturation of the fluid. Fourdifferent limit stresses were determined, two related to the yield point and two related to the flow point. Methods for determining limitstresses, especially due to excitation...
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Revalorization of the Szewalski binary vapour cycle
PublikacjaThe aim of the paper is to revalorizate of the Szewalski binary vapour cycle by analysing thermodynamical and operational parameters of this cycle. This was carried by accessible numerical CFM (Computational Flow Mechanics) codes type, by step-by-step modeling of separates apparatus. The binary vapour cycle is providing steam as the working fluid in the high temperature part of the cycle, while another fluid - a low boiling point...
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Localization of impulsive disturbances in archive audio signals using predictive matched filtering
PublikacjaThe problem of elimination of impulsive disturbances from archive audio signals is considered and its new solution, called predictive matched filtering, is proposed. The new approach is based on the observation that a large percentage of noise pulses corrupting archive audio recordings have highly repetitive shapes that match several typical “patterns”, called click templates. To localize noise pulses, click templates can be correlated...
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Hybrid Fuzzy-Ontological Project Framework of a Team Work Simulation System
PublikacjaThe aim of this article is to present the project framework for constructing a Software Process Simulation Modeling (SPSM) system. SPSM systems can be used as a virtual environment for the selection of methods and tools of project management in IT support organizations. The constructed system simulates the Scrum methodology, including the management processes and the project roles. For the implementation of Scrum processes, the...
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Coplanar Waveguide Fed Ultra-Wideband Antenna Over the Planar and Cylindrical Surfaces
PublikacjaThe investigation of coplanar waveguide fed ultra-wideband antenna and the influence of the proximity of different materials on the reflection coefficients and radiation character-istics is presented. The antenna is composed of two circular coplanar strips which enclose slot aperture of similar shape and is designed on a thin and flexible substrate. From the modeling and experimental tests the antenna shows good performance in...
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Analysis of EN 1993-1-6 guidelines about determining amplitudes of equivalent imperfections of steel cylindrical shells subjected to uniform external pressure
PublikacjaCivil engineering structures should be designed with reference to relevant standards. One of them is a Eurocode 3 standard EN 1993-1-6:2007: Design of steel structures Part 1-6: Strength and Stability of Shell Structures. According to this standard, the value of buckling load can be determined using different approaches: classical hand calculations (stress design) and geometrical and material non-linear analysis of an imperfect...
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Fractional Order Dynamic Positioning Controller
PublikacjaImproving the performance of Dynamic Positioning System in such applications as station keeping, position mooring and slow speed references tracking requires improving the position and heading control precision. These goals can be achieved through the improvement of the ship control system. Fractional-order calculus is a very useful tool which extends classical, integer-order calculus and is used in contemporary modeling and control...
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The difficulties in polybrominated diphenyl ethers identification by GC-EI-MS technique
PublikacjaAwareness about the harmful effects of brominated flame retardants on living organisms increases mainly due to link their presence in the human environment with health disorders. Therefore is a need to conduct research aimed at content control of these chemicals in the environment. Recent improvements in injection techniques and mass spectrometer ionization methods have led to a variety of options to determine PBDEs in environmental...
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Flow Analysis of a Kaplan Turbine
PublikacjaThis monograph is a guide to a method of experimental and numerical flow investigations for Kaplan - type turbines. The numerical calculations were compared with the test results of the model Kaplan turbine. The tests were carried out on the model test rig in the Gdańsk University of Technology. The turbine has been thoroughly experimentally investigated, resulting in the identification of optimum setting combination of the stator...
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SERVICE ORIENTED SCENARIOS FOR SUPPORT ENTERPRISE PROJECT MANAGEMENT
PublikacjaIn the paper, a service oriented architecture is used to describe various scenarios of human-oriented enterprises. They can be modeled by BPMN to show basic information flow. We consider business scenarios to present another modeling solution called service orchestration or service mashup. That approach gives an opportunity for the right management through taking the best possible choice of services, or composition of services....
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Analysis of dynamics of a map-based neuron model via Lorenz maps
PublikacjaModeling nerve cells can facilitate formulating hypotheses about their real behavior and improve understanding of their functioning. In this paper, we study a discrete neuron model introduced by Courbage et al. [Chaos 17, 043109 (2007)], where the originally piecewise linear function defining voltage dynamics is replaced by a cubic polynomial, with an additional parameter responsible for varying the slope. Showing that on a large...
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Pylon foundation of a cable stayed bridge at the motorway ring road of Wrocław
PublikacjaThe largest bridge of the motorway ring road of Wroclaw is a cable stayed bridge over the Odra river near Rędzin. Due to hydrogeological conditions of the ground it was not convenient to use standard bored piles of high length. Instead shorter piles were applied with additional improvement by cement injections at the pile toes. This decision was possible by extending ground investigation program and application of numerical modeling...
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Zastosowanie Systemu Informacji Geograficznej (GIS) w identyfikacji potencjalnych klastrów
PublikacjaPolityka klastrowania znajduje się w strategicznych dokumentach rozwoju gospodarczego Polski i nastawiona jest na promowanie współpracy regionalnej ponadregionalnej. Budowa klastra na szczeblu regionalnym wymaga jednak w pierwszym etapie jego identyfikacji a w kolejnym selekcji potencjalnych uczestników. Dotychczas stosowane jakościowe i ilościowe metody identyfikacji klastrów, nie są do takich zadań przystosowane lub ich stopień...
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Janusz Nieznański prof. dr hab. inż.
OsobyUrodził się w 1957 r. w Gdańsku. Jest absolwentem Wydziału Elektrycznego Politechniki Gdańskiej (1981). W 1990 r. uzyskał stopień doktora, w 1999 r. stopień doktora habilitowanego, a w 2015 r. tytuł profesora. Jest pracownikiem naukowo-dydaktycznym Politechniki Gdańskiej nieprzerwanie od ukończenia studiów. Jego zainteresowania naukowe obejmują sterowanie, diagnostykę, modelowanie i symulację układów energoelektronicznych i napędowych,...
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MACHINE LEARNING APPLICATIONS IN RECOGNIZING HUMAN EMOTIONS BASED ON THE EEG
PublikacjaThis study examined the machine learning-based approach allowing the recognition of human emotional states with the use of EEG signals. After a short introduction to the fundamentals of electroencephalography and neural oscillations, the two-dimensional valence-arousal Russell’s model of emotion was described. Next, we present the assumptions of the performed EEG experiment. Detail aspects of the data sanitization including preprocessing,...
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Chemical Vapor Transport Route toward Black Phosphorus Nanobelts and Nanoribbons
PublikacjaChemical vapor transport (CVT) method is widely used for bulk black phosphorus (BP) fabrication. In this work, we demonstrate that CVT provides a route for the fabrication of BP nanoribbons and nanobelts. This method consists of a two-step procedure, including initial BP column growth using the CVT technique, followed by ultrasonic treatment and centrifugation. The obtained nanostructures preserve BP column dimensions, forming...
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Diamond Structures for Tuning of the Finesse Coefficient of Photonic Devices
PublikacjaFinesse coefficient is one of the most important parameters describing the properties of a resonant cavity. In this research, a mathematical investigation of the application of diamond structures in a fiber-optic Fabry–Perot measurement head to assess their impact on the finesse coefficient is proposed. We present modeled transmission functions of cavities utilizing a nitrogen-doped diamond, a boron-doped diamond, nanocrystalline...
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Chemical Vapor Transport Route toward Black Phosphorus Nanobelts and Nanoribbons
PublikacjaChemical vapor transport (CVT) method is widely used for bulk black phosphorus (BP) fabrication. In this work, we demonstrate that CVT provides a route for the fabrication of BP nanoribbons and nanobelts. This method consists of a two-step procedure, including initial BP column growth using the CVT technique, followed by ultrasonic treatment and centrifugation. The obtained nanostructures preserve BP column dimensions, forming...
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Systematic Management of Simulation State for Multi-Branch Simulations in Simulink
PublikacjaSystematic simulation is a technique related and motivated by the formal analysis of hybrid dynamic systems. It combines the exhaustive and conservative nature of traditional model checking with numerical simulation for providing efficient algorithms to manage simulations. Multi-branch simulation is the concept advancing simulation efficiency by reducing the number of state transitions. This paper introduces an approach to implement...
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Hybrid model of geared rotor system
PublikacjaIn the paper a hybrid model of a geared multirotor system has been developed. The model is obtained by application of both the modal decomposition methodology and the spatial discretization method. Reduced modal model was constructed for the system without gyroscopic and damping effects. The gyroscopic interaction, damping and other phenomena which are difficult to include in the modal approach were modeled by application of simply...
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A simplified behavioral MOSFET model based on parameters extraction for circuit simulations.
PublikacjaThe paper presents results on behavior modeling of general purpose Metal-Oxide Semiconductor Field-Effect Transistor (MOSFET) for simulation of power electronics systems requiring accuracy both in steady-state and in switching conditions. Methods of parameters extraction including nonlinearity of parasitic capacitances and steady-state characteristics are based on manufacturer data sheet and externally measurable characteristics....
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Antifungal Activity of Homoaconitate and Homoisocitrate Analogs
PublikacjaThirteen structural analogs of two initial intermediates of the L-alpha-aminoadipate pathway of L-lysine biosynthesis in fungi have been designed and synthesized, including fluoro- and epoxy-derivatives of homoaconitate and homoisocitrate. Some of the obtainedcompounds exhibited at milimolar range moderate enzyme inhibitory properties against homoaconitase and/or homoisocitrate dehydrogenase of Candida albicans. The structural...
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Superconductivity on a Bi Square Net in LiBi
PublikacjaWe present the crystallographic analysis, superconducting characterization and theoretical modeling of LiBi, that contains the lightest and the heaviest nonradioactive metal. The compound crystallizes in a tetragonal (CuAu-type) crystal structure with Bi square nets separated by Li planes (parameters a = 3.3636(1)Å and c = 4.2459(2) Å, c/a = 1.26). Superconducting state was studied in detail by magnetic susceptibility and heat...
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Safety Assessment of the Regional Warmia and Mazury Road Network Using Time-Series Analysis
PublikacjaWarmia and Mazury still belongs to the areas with the smallest transport accessibility in Europe. Unsatisfactory state of road infrastructure is a major barrier to the development of the regional economy, impacting negatively on the life conditions of the population. Also in terms of road safety Warmia and Mazury is one of the most endangered regions in Poland. The Police statistics show that beside a high pedestrian risk observed...
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Semi-definite programming and quantum information
PublikacjaThis paper presents a comprehensive exploration of semi-definite programming (SDP) techniques within the context of quantum information. It examines the mathematical foundations of convex optimization, duality, and SDP formulations, providing a solid theoretical framework for addressing optimization challenges in quantum systems. By leveraging these tools, researchers and practitioners can characterize classical and quantum correlations,...
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Preliminary estimation of groundwater recharge on Brda river outwash plain
PublikacjaEstimation of groundwater recharge is one of the most challenging subjects in hydrogeology. It is a critical factor influencing the pollution migration, assessment of aquifer vulnerability to contamination, small-scale groundwater budget calculation, modeling of nutrient cycling and detailed flow path calculations. In Poland an infiltration rate method is widely used, which depends on a system of rate coefficients referring to...
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Markov Model of Disease Development and Recovery
PublikacjaMarkov models are commonly used to simulate diseases and allow modeling of multiple health states and outcomes. Starting with the well known Le Bras multistate model (cascading failure model) with time-independent transitions we will see how simple Markov mortality models may be pressed into the service of survival and event history analysis. We will focus on more complex models which will be able to take into account remission,...
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Simulation of the derecho event in Poland of 11th August 2017 using the WRF model and ERA5 data on pressure levels as initial conditions
Dane BadawczeThis series contains datasets related to the forecasting of a severe weather event, a derecho, in Poland on 11 August 2017. The simulations were conducted using the Weather Research and Forecasting (WRF) model version 4.2.1 with initial and boundary conditions from ERA5 on pressure levels. Simulation was performed for two starting hours: at 00:00 and...