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Dataset of non-isomorphic graphs of the coloring types (K4,K4;n), 1<n<R(4,4)
Dane BadawczeFor K4 graph, a coloring type (K4,K4;n) is such an edge coloring of the full Kn graph, which does not have the K4 subgraph in the first color (representing by no edges in the graph) or the K4 subgraph in the second color (representing by edges in the graph).The Ramsey number R(4,4) is the smallest natural number n such that for any edge coloring of...
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Occurrence and properties of sulphate reducing bacteria in groundwater in Gdańsk region; Selected methods of elimination.Bakterie redukujące siarczany na ujęciach wód podziemnych w regionie gdańskim.
PublikacjaGdańsk region is situated in the area with good hydrogeological conditions. The ground-water designed for drinking purposes is taken mainly from the Quaternary and addition-ally from Cretaceous aquifers. The urban development and intensive take off have caused the increase of water exploitation and as a consequence of the changes of hydrogeological conditions the deterioration of chemical and bacteriological quality of water has...
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Noise and Rolling Resistance Properties of Various Types of Winter Tyres Compared to Normal Car Tyres
PublikacjaTo cope with winter weather conditions, potentially including snow and ice, it is common to use winter tyres, or ”all-seasons” tyres assumed to be safe both in summer and winter. In some northern countries, winter tyres are mandatory. Traditionally, it has been assumed that winter tyres are noisier than normal tyres (here called summer tyres) and winter tyres equipped with studs are assumed to be very noisy.This paper presents...
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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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Enzyme-linked carbon nanotubes as biocatalytic tools to degrade and mitigate environmental pollutants
PublikacjaA wide array of organic compounds have been recognized as pollutants of high concern due to their controlled or uncontrolled presence in environmental matrices. The persistent prevalence of diverse organic pollutants, including pharmaceutical compounds, phenolic compounds, synthetic dyes, and other hazardous substances, necessitates robust measures for their practical and sustainable removal from water bodies. Several bioremediation and...
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Advanced Sensor for Non-Invasive Breast Cancer and Brain Cancer Diagnosis Using Antenna Array with Metamaterial-Based AMC
PublikacjaMicrowave imaging techniques can identify abnormal cells in early development stages. This study introduces a microstrip patch antenna coupled with artificial magnetic conductor (AMC) to realize improved sensor for non-invasive (early-stage) breast cancer and brain cancer diagnosis. The frequency selectivity of the proposed antenna has been increased by the presence of AMC by creating an additional resonance at 2.276 GHz associated...
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Hardware realization of shadow detection algorithm in FPGA
PublikacjaW referacie opisano problem detekcji cieni w sekwencjach wideo. Na podstawie metod znanych z literatury opracowano algorytm detekcji cieni, działający w czasie rzeczywistym i przeznaczony do realizacji sprzętowej w układzie FPGA. Algorytmy zostały przetestowane i porównane w środowisku MATLAB. Za pomocą języka VHDL zrealizowano system detekcji cieni wykorzystujący opracowany algorytm i zaimplementowano go w układzie Virtex-4. Został...
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Hydration of amino acids: FTIR spectra and molecular dynamics studies
PublikacjaThe hydration of selected amino acids, alanine, glycine, proline, valine, isoleucine and phenylalanine, has been studied in aqueous solutions by means of FTIR spectra of HDO isotopically diluted in H2O. The difference spectra procedure and the chemometric method have been applied to remove the contribution of bulk water and thus to separate the spectra of solute-affected HDO. To support interpretation of obtained spectral results,...
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Arching of railway turnouts by analytical design method
PublikacjaThe paper involved the issue of arching of the railway turnouts. This is an issue which is given relatively less attention to scientific and research activities. Reference has been made to the book by Wladyslaw Rzepka, under the title „Curved turnouts in plan and profile”, which has been used in Poland for more than 50 years as the main source of information relating to the turnouts on the curve. The book is a compilation of elaborations...
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Structural and luminescent study of TeO2-BaO-Bi2O3-Ag glass system doped with Eu3+ and Dy3+ for possible color-tunable phosphor application
PublikacjaTellurite glass systems of 73TeO2-4BaO-3Bi2O3-1Ag:xEu2O3-(2-x)Dy2O3 (where x = 0.5, 1, 1.5, 2 in molar ratio) composition have been successfully synthesized. In order to acquire Ag nanoparticles, materials have been heat treated at 350 °C in the air atmosphere. Structural properties of obtained samples were evaluated with various techniques. X-Ray Diffraction (XRD) measurements indicated that obtained materials are amorphous in...
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Theoretical calculation of the physico-chemical properties of 1-butyl-4-methylpyridinium based ionic liquids
PublikacjaACCEPTED MAIonic liquids (ILs) have attracted much attention for their unique physicochemical properties, which can be designed as needed by altering the ion combinations. Besides experimental work, numerous computational studies have been concerned with prediction of physical properties of ILs. The results of molecular dynamics simulations of ILs depend strongly on the proper force field parameterization. Classical force fields...
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Influence of artificial thermal ageing on polyester-reinforced and polyvinyl chloride coated AF9032 technical fabric
PublikacjaThe presented work deals with the thermal ageing evaluation for polyester-reinforced and polyvinyl chloride coated fabrics. The architectural fabric AF9032 was exposed to artificial thermal ageing by subjecting the material samples to temperature levels of 80℃ and 90℃ for up to 12 weeks. The mechanical properties of the aged fabric have been separately described by the identified linear piecewise model (with assumption of the elastic...
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Two-photon perimetry utilizing picosecond laser
PublikacjaAge-related impairments are becoming more and more severe for aging societies. The sensory organ diseases are particularly troublesome as they exclude seniors from their everyday activity. Therefore, maintaining good quality eyesight is essential for normal functioning. New medical therapies help restrain age-related changes, but still, monitoring is essential to the treatment process. Humans do not have the natural ability to...
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Ship weather routing featuring w-MOEA/D and uncertainty handling
PublikacjaThe paper presents a new version of evolutionary multi-objective weather routing (WR) for ships taking into account uncertainties of weather forecasts in route optimization. The method applies authors’ w-MOEA/D algorithm: MOEA/D framework incorporating Decision Maker’s (DM) preferences by means of w-dominance relation. Owing to this, DM preferences are taken into account throughout optimization, allowing the process to focus on...
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Analytical design method for widening the intertrack space
PublikacjaThe paper involved the issue of arching of the railway turnouts. This is an issue which is given relatively less attention to scientific and research activities. Reference has been made to the book by Wladyslaw Rzepka, under the title „Curved turnouts in plan and profile”, which has been used in Poland for more than 50 years as the main source of information relating to the turnouts on the curve. The book is a compilation of elaborations...
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Study of the anticancer potential of Cd complexes of selenazoyl-hydrazones and their sulfur isosters
PublikacjaThe biological activity of Cd compounds has been investigated scarce since Cd has been recognized as a human carcinogen. However, the toxicity of cadmium is comparable to the toxicity of noble metals such as Pt and Pd. The paradigm of metal toxicity has been challenged suggesting that metal toxicity is not a constant property, yet it depends on many factors like the presence of appropriate ligands. Studies on anticancer activity...
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Model studies to identify input parameters of an algorithm controlling electric supply/consumption process by underground iron ore enterprises
PublikacjaPurpose is the development of the research format of a mathematical model to select and assess input parameters of an algorithm controlling distribution of electric energy flows in the monitoring structure of electricity supply/ consumption by using equipment of mining enterprises engaged in underground iron ore raw materials extraction. Methods. The analytical research involved a theory of random processes adapted to the real...
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CULTURAL DETERMINANTS OF EVIDENCE-BASED HUMAN RESOURCES MANAGEMENT: A CROSS-COUNTRY ANALYSIS
PublikacjaPurpose: This paper aims at providing comparative analysis of the influence of cultural determinants on the managers’ perceptions of human resources management practices, as a factor conditioning application of evidence-based management. Design/methodology/approach: This article presents the study of 121 managers in Poland, on their perception of HRM practices and analyses the consistency of findings with the Hofstede cultural...
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Technical diagnostics and monitoring of traction current collectors
PublikacjaNew evaluation methods of the technical condition of rolling stock current collectors are proposed in this paper. The method of automatic measurement of the pantograph static force characteristic, realized when the vehicle runs through the test section of the track with especially prepared overhead line height distribution, has been practically implemented by the Polish Railways. The method of testing the slipper spring suspension...
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Simulation model for evaluation of QoS routing algorithm in large packet networks
PublikacjaThe variety of traffic transferred via current telecommunication networks includes also voice, which should meet quality requirements. One of mechanisms, which can support QoS in current packet networks, is routing. There exist many routing proposals which should introduce the QoS into the network but practically they don't. Following paper presents the realization of simulation model for evaluation of a new routing algorithm DUMBRA...
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Measurement of activity coefficients at infinite dilution of organic solutes in the ionic liquid 1-hexyl-1,4-diaza[2.2.2]bicyclooctanium bis(trifluoromethylsulfonyl)imide using gas–liquid chromatography
PublikacjaBased on gas–liquid chromatography (GLC) retention data, activity coefficients at infinite dilution of 39 different solutes in the ionic liquid 1-hexyl-1,4-diaza[2.2.2]bicyclooctanium bis(trifluoromethylsulfonyl)imide ([HDABCO][NTf2]) have been determined. Measurements covered a broad range of types of organic solutes including alkanes, alcohols, ketones, benzene derivatives and McReynold’s compounds. Activity coefficients were...
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Tyre/road noise of passenger car tyres, including tyres for electric vehicles - road measurements
PublikacjaThe paper presents the results from CPX measurements of tyre/road noise performed for selected passenger car tyres, including the tyres especially designed for electric vehicles. The tyres have been measured when rolling on several typical road surfaces in Norway and in Poland. In addition, the tyres have been measured on some very low noise road surfaces, such as a the poroelastic road surface (PERS). The measurement results...
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Low-Cost EM-Simulation-Driven Multi-Objective Optimization of Antennas
PublikacjaA surrogate-based method for efficient multi-objective antenna optimization is presented. Our technique exploits response surface approximation (RSA) model constructed from sampled low-fidelity antenna model (here, obtained through coarse-discretization EM simulation). The RSA model enables fast determination of the best available trade-offs between conflicting design goals. A low-cost RSA model construction is possible through...
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Analysis of unsteady flow forces on the thermowell of steam temperature sensor
PublikacjaIn this paper, 3D numerical analysis of unsteady flow forces acting on the measuring sheath of steam temperature is presented. According to that purpose, the CFD (Computation Fluid Dynamic [1]) approach has been used. The nonstationary of fluid acting on the measuring sheath such as: Strouhal frequency, amplitude of pressure, structure of vortex, peak of pressure, field of pressure, field of velocity etc. are studied analytically...
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Numerical Analysis of a Steel Frame Building with Soft-storey Failure under Ground Motion Excitation
PublikacjaThe aim of this paper is to show the results of a numerical analysis focused on the behaviour of multi-storey steel frame building that suffers from a soft-storey failure under ground motion excitation. A numerical model of the structure was created in FEM computer software and was exposed to an impact that would have been generated after a soft-storey failure due to falling of the upper floors. During the analysis, the whole structure...
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Biosilica from sea water diatoms algae—electrochemical impedance spectroscopy study
PublikacjaHere, we report on an electrochemical impedance study of silica of organic origin as an active electrode material. The electrode material obtained from carbonized marine biomass containing nanoporous diatoms has been characterised by means of XRD, IR, SEM and EIS. Dif- ferent kinds of crystallographic phases of silica as a result of thermal treatment have been found. The electrode is electrochemically stable during subsequent cyclic...
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Model Correction and Optimization Framework for Expedited EM-Driven Surrogate-Assisted Design of Compact Antennas
PublikacjaDesign of compact antennas is a numerically challenging process that heavily relies on electromagnetic (EM) simulations and numerical optimization algorithms. For reliability of simulation results, EM models of small radiators often include connectors which—despite being components with fixed dimensions—significantly contribute to evaluation cost. In this letter, a response correction method for antenna models without connector,...
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Determination of magnetisation conditions in a Double-Core Barkhausen Noise measurement set-up
PublikacjaThe magnetic Barkhausen effect is useful forassessing 1D and 2D stress states of ferromagnetic steelobjects. However, its extension to technically importantmaterials, such as duplex anisotropic steels, remains challenging. The determination of magnetisation inside the studied object and the electromagnet for various geometries, materials and magnetisation angles is a key issue.Three-dimensional, dynamic finite element analysis...
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Pressure drop of HFE7000 and HFE7100 during flow condensation in minichannels
PublikacjaAttention is focused on the issues of flow resistance and pressure drop of perspective refrigeration fluids during condensation in the two-phase flow in minichannels. The case of the flow through a cylindrical single channel of 2.3 mm inner diameter was carefully analyzed. Pressure drop tests have been performed in diabatic flow conditions. The effect of heat flux, mass flux, vapour quality and saturation temperature on the two-phase...
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Effects of Surface Energy and Surface Residual Stresses on Vibro-Thermal Analysis of Chiral, Zigzag, and Armchair Types of SWCNTs Using Refined Beam Theory
PublikacjaIn this article, vibration characteristics of three different types of Single-Walled Carbon Nanotubes (SWCNTs) such as armchair, chiral, and zigzag carbon nanotubes have been investigated considering the effects of surface energy and surface residual stresses. The nanotubes are embedded in the elastic substrate of the Winkler type and are also exposed to low and high-temperature environments. A new refined beam theory namely, one-variable...
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Unidirectional DC/DC Converter with Voltage Inverter for Fast Charging of Electric Vehicle Batteries
PublikacjaThe paper proposes the adaptation of the industrial plant’s power network to supply electric vehicle (EV) fast-charging converters (above 300 kW) using renewable energy sources (RESs). A 600 V DC microgrid was used to supply energy from RESs for the needs of variable speed motor drives and charging of EV batteries. It has been shown that it is possible to support the supply of drive voltage frequency converters (VFCs) and charging...
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Aiming at methods’ wider adoption: Applicability determinants and metrics
PublikacjaNumerous computer science methods and techniques have been proposed by the scientific community. However, depending on the domain, only their minor fraction has met wider adoption. This paper brings attention to the concept of applicability - the notion that is well acknowledged in the scientific field but have not been analysed with respect to determinants, metrics and systematisation. The primary objective of the study was to...
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Determination of the Theoretical and Actual Working Volume of a Hydraulic Motor—Part II (The Method Based on the Characteristics of Effective Absorbency of the Motor)
Publikacja: In this article, the second method of determination of the theoretical and actual working volume of a hydraulic motor is described. The proposed new method is based on the characteristics of effective absorbency of the motor. The effective absorbency has been defined as the ratio of flow rate in a motor to the rotational speed of the motor’s shaft. It has been shown that the effective absorbency is a nonlinear function of the...
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Current divider-based nanosecond high current pulse measuring systems
PublikacjaThis paper presents the analysis of the new approach to the measurement methodology of significant values (in order of hundreds of kA) and huge steepness (in order of MA/μs) current pulses based on current dividers along with a comparison of the various types transducers suitability in measuring systems with such extreme parameters. Such dividers are used to extend the measurement ranges of current transducers with limited current...
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Photoluminescence of partially reduced Eu2+/Eu3+ active centers in a NaF–Al2O3–P2O5 glassy matrix with tunable smooth spectra
PublikacjaIn this work, a series of photoluminescent materials have been synthesized based on optically transparent and chemically stable glasses of the nominal composition Na3Al2(PO4)2F3 (NaF–Al2O3–P2O5 system) doped with 1 wt% of europium. It has been shown that the synthesis conditions (mainly the temperature and duration of the melting stage under reducing conditions) strongly affected the photoluminescence spectra of the material. This...
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Ferrofluids based analytical extractions and evaluation of their greenness
PublikacjaFerrofluids are stable dispersions of magnetic nanoparticles in a carrier liquid. They have attracted considerable attention in analytical extractions as they combine fluid-like properties with magnetic character, providing magnetic control over the extraction process. The synthesis of ferrofluids is very straightforward, and it generally involves the preparation of magnetic nanoparticles, their coating, and then mixing in a suitable...
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A new relevant membrane application: CO2 direct air capture (DAC)
PublikacjaSince carbon dioxide (CO2) is the primary greenhouse gas emitted into the atmosphere due to human activities, strong research efforts have been developed towards capturing and decreasing its production. Unfortunately, specific processes and activities make it impossible to avoid CO2 emissions. Among the different strategies scientists propose for CO2 reduction, direct CO2 capture from the atmosphere, also known as direct air capture...
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Activity-based payments: alternative (anonymous) online payment model
PublikacjaElectronic payments are the cornerstone of web-based commerce. A steady decrease in cash usage has been observed, while various digital payment technologies are taking over. They process sensitive personal information raising concerns about its potentially illicit usage. Several payment models that confront this challenge have been proposed. They offer varying levels of anonymity and readiness for adoption. The aim of this study...
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Selected dynamic properties of adaptive proportional observer of induction motor state variables
PublikacjaThis paper presents problems related to the design and the stability of adaptive proportional observer which is used for estimation of magnetic flux and motor speed in sensorless control systems of induction motor. The gain matrix of the observer was chosen by genetic algorithm and alternatively by pole placement method. It has been shown that adaptive proportional observer is stable if the...
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Thermophysical Properties of the Phase Change Material Mixtures – Preliminary Studies on Macromolecular Hydrocarbons Example.
PublikacjaThe aim of this work is a theoretical and experimental analysis of the macromolecular hydrocarbons mixtures composition and the impact on thermophysical parameters of the phase change materials (PCM) made from these mixtures. The analysis of the current state of knowledge extended by the author's own studies have been presented. Thermophysical characteristics of the hydrocarbons and their mixtures have been specified, in such a...
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PROBLEMS WITH CORROSION PROTECTION STEEL STACKS IN FGD SYSTEMS
PublikacjaThis paper presents problems associated with corrosion of steel stacks and changes in philosophy of corrosion protection when implemented into flue gas desulphurization systems. In-situ tests were taken by means of electrochemical impedance spectroscopy at a stack which discharges flue gas before wet lime/limestone desulphurization. A very rapid soaking of spherical infill vinylester coating with electrolyte has been observed....
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Thermophysical properties of the phase change material mixtures – preliminary studies on macromolecular hydrocarbons example.
PublikacjaThe aim of this work is a theoretical and experimental analysis of the macromolecular hydrocarbon mixtures composition and the impact on thermophysical parameters of the phase change materials (PCM) made from these mixtures. The analysis of the current state of knowledge extended by the author’s own studies have been presented. Thermophysical characteristics of the hydrocarbons and their mixtures have been specified, in such a...
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Space-mapping-based design flow of miniaturized broadband matching transformer with perforated metallization
PublikacjaA fast design procedure of unconventional passive components has been presented and experimentally validated on the basis of a wideband microstrip four-section matching transformer (50:6 OHm). A classic impedance matching circuit has been miniaturized by means of compact microstrip resonant cells (CMRCs) leading to a considerable length reduction (34%) together with minor degradation in its performance. The spacemapping-based design...
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EXHAUST TEMPERATURE MEASUREMENTS OF THE MARINE TURBOCHARGED DIESEL ENGINES IN OPERATION
PublikacjaThe article presents the selected metrology issues concerning the exhaust temperature of the turbocharged marine engines during operation. The special concern has been paid on existing disturbances as well as thermodynamical interpretation of the recorded measurement signal. A diagnostic informativeness of the standard exhaust temperature’s measurements has worked out while the engine runs in steady states has been also considered...
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Methods for evaluating rated power of diesel-powered generator set
PublikacjaBasic concepts for evaluating rated power of generator sets powered by combustion engines are presented in this article. A relation between parameters of the engine and the generator are shown. Recommendations contained in the standards and technical literature are systematized. The scheme and methodology for evaluating rated power of the generator set, based on laboratory research, are suggested. Also, the main problems which...
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Analysis of higher recombination orders in organic bulk heterojunction solar cells
PublikacjaRecently, it has been experimentally demonstrated that an order of nongeminate recombination exceeds two in some types of organic bulk heterojunction donor-acceptor structures. This result is different than for the case of bimolecular recombination described by Langevin theory. Although several theoretical explanations of this effect have been presented, the origin of higher recombination orders is still questionable. In this work,...
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Dilemmas associated with the implementation of quality management systems in Polish smaller health care units
PublikacjaThe article presents the considerations and recommendations for the implementation of the process-oriented quality management systems (QMS) in small health care units. As an example, the unit providing services for children with disabilities (therapy and rehabilitation) localized in northern part of Poland have been selected. The essential elements of the implementation of the quality system, taking into account the objectives...
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RADIATION OF HIGH INTENSITY SOUND BY CIRCULAR DISC BY MEANS OF THE NUMERICAL METHOD
PublikacjaThe main goal of this paper is to find sound pressure distribution radiated by the circular piezoelectric disc that vibrates with the finite amplitude. There has been presented the pressure distribution close to the radiating surface. Also it is shown the sound pressure distribution in the 3D form. The mathematic modeling was carried out on the base of the nonlinear acoustic equation with the proper boundary condition. The axial...
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Air flow phenomena in the model of the blind drift
PublikacjaIn the presented paper, Particle Image Velocimetry (PIV) has been used to investigate flow pattern and turbulent structure in the model of blind drift. The presented model exist in mining, and has been analyzed to resolve ventilation issues. Blind region is particularly susceptible to unsafe methane accumulation. The measurement system allows us to evaluate all components of the velocity vector in channel cross-section simultaneously....
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Electron energy-loss spectroscopy of excited states of the pyridine molecules
PublikacjaElectron energy-loss spectra of the pyridine, C5H5N, molecules in the gas phase have been measured to investigate electronic excitation in the energy range 3.5–10 eV. The applied wide range of residual electron energy and the scattering angle range from 10 ◦ to 180 ◦ enabled to differentiate between optically-allowed and -forbidden transitions. These measurements have allowed vertical excitation energies of the triplet excited...