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BJS-03 DO WE NEED FIXATION OF THE MESH IN LAPAROENDOSCOPIC TECHNIQUES FOR M3 INGUINAL DEFECTS? AN EXPERIMENTAL STUDY
PublicationThe authors conducted a research experiment to verify the hypothesis that it is possible to preserve the mesh in the operating field in large direct hernias (M3) without the need to use fixing materials. The results showed that mesh fixation is not the only alternative to preventing recurrence in complex defects and that the type of implant seems to be a key factor from the point of view of mechanics and biophysics.
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Existence of unbounded solutions to parabolic equations with functional dependence
PublicationThe Cauchy problem for nonlinear parabolic differential-functional equations is considered. Under natural generalized Lipschitz-type conditions with weights, the existence and uniqueness of unbounded solutions is obtained in three main cases: (i) the functional dependence u(·); (ii) the functional dependence u(·) and ∂xu(·); (iii) the functional dependence u(·)and the pointwise dependence ∂xu(t,x).
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Membranowe przekrycia wiszące -zagadnienia konstrukcyjno-materiałowe. Membrane hanging roof - constructional-material problems.
PublicationArtykuł przedstawia przykłady zastosowania membranowych przekryć wiszących w budownictwie ogólnym. Dodatkowo zwraca uwagę na wybrane zagadnienia konstrukcyjno-materiałowe tego typu obiektów.This paper presents the application examples of membrane hanging roof in building engineering. Additionally, attention to the chosen constructional-material problems of this type of structures has been focused.
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Monometallic nanoparticles decorated and rare earth ions doped KTaO3/K2Ta2O6 photocatalysts with enhanced pollutant decomposition and improved H2 generation
PublicationNew, monometallic nanoparticles (MNPs) decorated surface and rare earth (RE) ions doped lattice of perovskite-type (KTaO3)/pyrochlore-type (K2Ta2O6) photocatalysts were successfully prepared by facile hydrothermal incorporation of RE ions into KTaO3/K2Ta2O6 lattices followed by photodeposition of MNPs. The impact of noble metal type (MNPs = Au, Pt, Rh) and rare earth dopant type (RE = Er, Pr) on the physicochemical properties correlated...
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Mural i jego rola w przestrzeni zurbanizowanej
PublicationCzym tak naprawdę jest mural? Definicji jest bardzo wiele. Według Słownika języka polskiego PWN mural to „wielkie malowidło wykonane bezpośrednio na ścianie budynku”. Pierwotnymi malowidłami tego typu były prace naskalne z epoki paleolitu. Następnie ważnymi epokami dla rozwoju tego typu prac był starożytny Egipt i starożytny Rzym. Samo słowo „mural” pochodzi z języka hiszpańskiego (h. mural – ścienny; malarstwo ścienne). To dzięki...
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Recovery and re-use of photovoltaic solar cells from crystalline silicon
PublicationCrystalline silicon-type PV modules consist, in order of mass, of glass, an aluminium frame, an EVA coating, solar cells, a terminal box, back film and tapping screws. From the economic point of view, pure silicon, recoverable from spent cells, is the most important material owing to its cost and shortage. For crystalline, silicon-based PV cells, the following chemical treatments were performed: removal of the metal coating, followed...
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Determination of toxic gases based on the responses of a single electrocatalytic sensor and pattern recognition techniques
PublicationA response from an electrocatalytic gas sensor contains fingerprint information about the type of gas and its concentration. As a result, a single gas sensor can be used for the determination of different gases. However, information about the type of gas and its concentration is hidden in the unique shape of the current–voltage response and it is quite difficult to explore. One of the ways to get precise information about the measured...
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New potential functions for greedy independence and coloring
PublicationA potential function $f_G$ of a finite, simple and undirected graph $G=(V,E)$ is an arbitrary function $f_G : V(G) \rightarrow \mathbb{N}_0$ that assigns a nonnegative integer to every vertex of a graph $G$. In this paper we define the iterative process of computing the step potential function $q_G$ such that $q_G(v)\leq d_G(v)$ for all $v\in V(G)$. We use this function in the development of new Caro-Wei-type and Brooks-type...
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DYNAMIC ANALYSIS OF HISTORIC RAILWAY BRIDGES IN POLAND IN THE CONTEXT OF ADJUSTING THEM TO PENDOLINO TRAINS
PublicationThe article presents the dynamic analysis of the historic railway bridge in Tczew as an example of the usefulness of such type of bridge for high-speed trains. The model of the bridge and the simulation of rolling stock passage was performed in SOFISTIK program. The scope of work includes experimental studies, the solution of the problem concerning the correct solution features dynamic model takes into account the dependencies...
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Analysis of abrasive particle trajectories during single-sided lapping process with driven conditioning ring
PublicationIn this paper new kinematics systems were studied for a single lapping process. In order to ensure the constant profile wear of the tool a standard kinematic system can be changed. Lapping is carried out by applying loose abrasive grains between two surfaces and causes a relative motion between them. The result is a finish of multi-directional lay. During process, the mechanism of surface formation are decisively affected by a...
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Discrimination of selected fungi species based on their odour profile using prototypes of electronic nose instruments
PublicationThe paper presents practical application of an electronic nose technique to fast and efficient discrimination of the samples of different fungi species such as: Penicillium chrysogenum, Cladosporium herbarum, Rhizopus oryzae, Alternaria alternata. Two prototypes of electronic nose instrument were utilized for investigation of discrimination capability with respect to odour profile of these fungi: the first prototype was based on...
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An improved scalable method of isolating asphaltenes
PublicationA new, improved and scalable procedure of asphaltene fraction isolation is presented and compared to standard test methods. The new procedure uses 1:40 feedstock to solvent (n-heptane) ratio (g/mL), filtration through a cellulosic thimble and extensive washing in a Soxhlet type extractor. The group type composition and purity of the asphaltene fractions have been examined using thin-layer chromatography with flame-ionization detection....
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An electronic nose based on the semiconducting and electrochemical gas sensors
PublicationThe practical application of human nose for fragrance recognition is severely limited by the fact that our sense of smell is subjective and gets tired easily. Consequently, there is a significant need for an instrument that can be a substitution of the human sense of smell. Development of an electronic nose devices is an active area of research starting from pioneering research of Dodd and Persuad in the mid-1980s. Such systems...
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Minichannel and minigap classification criteria based on the aspect ratio of the minigeometry: A numerical study
PublicationA detailed numerical investigation has been carried out to analyze the diabatic flow distribution and velocity profile in 18 minigeometries with various aspect ratios for V-type and I-type flow configurations (for 36 cases) assuming ethanol as a working fluid. The aim of the study is to distinguish the value of the aspect ratio for which the flow in minigeometry starts to be two-dimensional (minigap). Cases with a constant Reynolds...
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Evaluation of Medical Staff Satisfaction for Workplace Architecture in Temporary COVID-19 Hospital: A Case Study in Gdańsk, Poland
PublicationThis article analyses the architecture that was used in the temporary AmberExpo hospital in Gdańsk, Poland which was installed during the COVID-19 pandemic. The construction of this type of facility is often based on experimental approaches, aimed at caring for patients suffering from an infectious disease in emergency conditions. In order to assess the level of employee satisfaction with the architectural and technical elements...
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Study of Metrological Properties of Voltammetric Electrodes in the Time Domain
PublicationMetrological properties of voltammetric electrodes, in the situation where on their surface an electrochemical reaction of oxidizing/reduction takes place, were analyzed in this chapter. The properties of electrodes on which a reaction controlled by ion transport process takes place were taken into consideration. Also, it was analyzed how the electrode’s shape and the voltage polarizing the electrode influence this electrode’s...
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Determination of Odour Interactions in Gaseous Mixtures Using Electronic Nose Methods with Artificial Neural Networks
PublicationThis paper presents application of an electronic nose prototype comprised of eight sensors, five TGS-type sensors, two electrochemical sensors and one PID-type sensor, to identify odour interaction phenomenon in two-, three-, four- and five-component odorous mixtures. Typical chemical compounds, such as toluene, acetone, triethylamine, α-pinene and n-butanol, present near municipal landfills and sewage treatment plants were subjected...
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Propagation of initially sawtooth periodic and impulsive signals in a quasi-isentropic magnetic gas
PublicationThe characteristics of propagation of sawtooth periodic and impulsive signals at a transducer are analytically studied in this work. A plasma under consideration is motionless and uniform at equilibrium, and its perturbations are described by a system of ideal magnetohydrodynamic equations. Some generic heating/cooling function, which in turn depends on equilibrium thermodynamic parameters, may destroy adiabaticity of a flow and...
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Influence of process of straightening ship hull structure made of 316L stainless steel on corrosion resistance and mechanical properties
PublicationThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries, for architectural elements, and many others. The chemical composition of corrosion-resistant...
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MULTI-CRITERIA INVESTMENT DECISION SUPPORT MODEL USING FUZZY ANALYTIC HIERARCHY PROCESS (F-AHP) METHOD FOR POWER INDUSTRY
PublicationIn this paper, the comparative analysis of two wind farm construction projects was presented. This particular type of analysis is commonly applied before purchasing investment project being in a planning phase by a company interested in its development. Conduction of this type of analysis is prompted by the necessity to take into consideration the requirements of Polish legislation. Comparison of wind farm construction projects...
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Waste Tyres Pyrolysis for Obtaining Limonene
PublicationThis review deals with the technologies of limonene production from waste tyre pyrolysis. Thermal decomposition is attractive for tackling the waste tyre disposal problem, as it enables both: energy to be recovered and limonene to be obtained. This material management recycling of tyres is environmentally more beneficial than the burning of all valuable products, including limonene. Given this recoverability of materials from waste...
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Types of Markov Fields and Tilings
PublicationThe method of types is one of the most popular techniques in information theory and combinatorics. However, thus far the method has been mostly applied to one-dimensional Markov processes, and it has not been thoroughly studied for general Markov fields. Markov fields over a finite alphabet of size m ≥ 2 can be viewed as models for multi-dimensional systems with local interactions. The locality of these interactions is represented...
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Experimental investigation of thermal energy storage in shell-and-multi-tube unit with nano-enhanced phase change material
PublicationThis paper deals with thermal energy storage with use of nanoparticle enhanced phase change material in shell-and-multitube unit. The experiments are conducted under atmospheric pressure. Paraffin wax and two different fatty acids are used as base phase change material. Graphite and multi-walled carbon nanotubes serve as nanoparticles. Graphite nanoparticles are tested at the concentrations of 0.1%, 1% and 5% by weight, while multi-walled...
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EHD Flow Measured by 2D PIV in a Narrow Electrostatic Precipitator with Longitudinal Wire Electrode
PublicationIn this paper, results of the electrohydrodynamic (EHD) flow patterns in two narrow ESPs with longitudinally-to-flow wire electrode arepresented. The influence of the ESP geometry on the EHD flow generated in the ESP was investigated. The results obtained from 2-dimensional(2D) Particle Image Velocimetry (PIV) showed similarities and differences of the particle flow in the wire-plate and wire-cylinder type ESP.
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EHD Flow Measured by 2D PIV in a Narrow Electrostatic Precipitator with Longitudinally-to-flow Wire Electrode
PublicationIn this paper, results of the electrohydrodynamic (EHD) flow patterns in two narrow ESPs with longitudinally-to-flow wire electrode are presented. The influence of the ESP geometry on the EHD flow generated in the ESP was investigated. The results obtained from 2 dimensional (2D) Particle Image Velocimetry (PIV) showed similarities and differences of the particle flow in the wire-plate and wire-cylinder type ESP.
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Different types of solvability conditions for differential operators
PublicationSolvability conditions for linear differential equations are usually formulated in terms of orthogonality of the right-hand side to solutions of the homogeneous adjoint equation. However, if the corresponding operator does not satisfy the Fredholm property such solvability conditions may be not applicable. For this case, we obtain another type of solvability conditions, for ordinary differential equations on the real axis, and...
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Selective jamming of OFDM transmission in NB-IoT radio interface
PublicationThe paper presents the concept of smart jamming, which involves selective interference aimed at critical components of the OFDM signal. Research verifying the feasibility of this type of electronic attack are described. A realized testbed for jamming real NB-IoT signals in a downlink is presented. The test results demonstrate the feasibility of realizing selective jamming and its greater effectiveness compared to barrage interference.
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Application of method of differential magnetometric system for detection of sunken objects
PublicationThis paper presents a magnetometric system with scalar sensors mounted on two independent platforms, which is used to detect sunken shipwrecks. Increasing the distance between the sensors allows for more precise measurement of the difference in the magnetic induction module than in the case of sensors mounted e.g. on the aeroplane’s wings. This type of system makes it possible to enlarge detection range of the sunken wrecks.
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Comparison of target strength (TS) distributions obtained by means of the use of direct and indirect techniques in sea cages
PublicationThe aim of this study is to verify the reliability of a processing application developed for the indirect measurement of target strength (TS), with a view to the integration into a single-beam system for its utilization in fish farms. Dorsal and ventral measurements are carried out for gilt-head sea-bream (Spams Aurata) for 5 size classes using a split-beam EK60 echosounder and single-beam data obtained from one of the channels...
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Forced degradation studies of ivabradine and in silico toxicology predictions for its new designated impurities
PublicationAll activities should aim to eliminate genotoxic impurities and/or protect the API againstdegradation. There is a necessity to monitor impurities from all classification groups,hence ivabradine forced degradation studies were performed. Ivabradine was provedto be quite durable active substance, but still new and with insufficient stability data.Increased temperature, acid, base, oxidation reagents and...
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Business continuity management framework for Industry 4.0 companies regarding dependability and security of the ICT and ICS/SCADA system
PublicationThis chapter addresses a business continuity management (BCM) framework for the Industry 4.0 companies including the organizational and technical solutions, regarding the dependability and security of the information and telecommunication technology (ICT), and the industrial control system (ICS) / supervisory control and data acquisition (SCADA) system. These technologies and systems play nowadays important roles in modern advanced...
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Enhancing Economic Development Through ICT-Based Governance: Evidence for Developing Countries
Publicationhis shows novel empirical evidence on how e-government solutions enhance the emergence of inclusive societies, increase institutional quality, and through that channels dynamize economic development in developing countries. With this aim we examine digital development inequalities adopting 2 core ICT indicators: mobile cellular telephony and Internet users; and gross per capita income and Human Development Index to show the level...
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Joint experimental and theoretical study on electron scattering from titanium tetrachloride (TiCl4) molecule
PublicationAbsolute grand-total cross section for electron scattering from titanium tetrachloride, TiCl4, molecule was measured at electron-impact energies ranging from 0.3 to 300 eV, in the linear electron-transmission experiment. The elastic integral, differential, momentum transfer, and total ionization cross sections for TiCl4 molecule were also calculated for low and intermediate collisional energies at the level of various theories. The...
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Localization of impulsive disturbances in audio signals using template matching
PublicationIn this paper, a new solution to the problem of elimination of impulsive disturbances from audio signals, based on the matched filtering technique, is proposed. The new approach stems from the observation that a large proportion of noise pulses corrupting audio recordings have highly repetitive shapes that match several typical “patterns”. In many cases a representative set of exemplary pulse waveforms can be extracted from the...
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The Role of Electron Transfer in the Fragmentation of Phenyl and Cyclohexyl Boronic Acids
PublicationIn this study, novel measurements of negative ion formation in neutral potassium-neutral boronic acid collisions are reported in electron transfer experiments. The fragmentation pattern of phenylboronic acid is comprehensively investigated for a wide range of collision energies, i.e., from 10 to 1000 eV in the laboratory frame, allowing some of the most relevant dissociation channels to be probed. These studies were performed in...
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Effect of free water on the quasi‑static compression behavior of partially‑saturated concrete with a fully coupled DEM/CFD approach.
PublicationThe work aims to numerically investigate the quasi-static response of partially fluid-saturated concrete under two-dimensional uniaxial compression at the mesoscale. We investigated how the impact of free pore fluid content (water and gas) affected the quasi-static strength of concrete. The totally and partially fluid-saturated concrete behavior was simulated using an improved pore-scale hydro-mechanical model based on DEM/CFD....
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Control of mass concentration of reagents by sound in a gas with nonequilibrium chemical reactions
PublicationThe weakly nonlinear dynamics of a chemically reacting gas is studied. Nonlinear interaction of acoustic and nonacoustic types of motion are considered. We decompose the base equations using the relationships of the gas-dynamic perturbations specific for every type of motion. The governing equation for the mass fraction of a reagent influenced by dominating sound is derived and discussed. The conclusions concern the equilibrium...
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Analisys of the failure of fixator used in bone surgery
PublicationThe Gamma nail (fixator) made of stainless steel, which has broken in the body, was subjected to examination. The fixator was removed from the patient femur. The fracture occurred in the area of the nail hole after two months' stay in the organism. The research included chemical composition, hardness of the Gamma nail material and the observation and analysis of the type of fracture. The research showed the fatigue failure of the...
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New approach to noncausal identification of nonstationary stochastic systems subject to both smooth and abrupt parameter changes
PublicationIn this paper we consider the problem of finiteintervalparameter smoothing for a class of nonstationary linearstochastic systems subject to both smooth and abrupt parameterchanges. The proposed parallel estimation scheme combines theestimates yielded by several exponentially weighted basis functionalgorithms. The resulting smoother automatically adjustsits smoothing bandwidth to the type and rate of nonstationarityof the identified...
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Wear of Ultra-thin DLC or Tungsten-modified DLC Coatings under Reciprocating Sliding
PublicationIn the paper results are presented from tests in reciprocating sliding of self mated specimens of DLC and tungsten modified DLC coatings on stainless steel substrate. The contact geometry chosen for the research task was ball on flat. The contacts were lubricated either with distilled water or medical saline solution. Results are presented with regard to wear resistance as a function of material type and lubricant used.
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Polyethylene glycol-coated solid-phase microextraction fibres for the extraction of polar analytes-A review
PublicationThe article discusses the merits and limitations of commercially available solid-phase microextraction (SPME) fibres and compares them with the new type of extraction coatings, in particular those containing polyethylene glycol as sorbent, as well as the methods of the preparation of the latter. It also analyses their possible application for the extraction of a broad spectrum of analytes, with particular emphasis on the sampling...
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On a Method of Efficiency Increasing in Kaplan Turbine
PublicationThis paper presents a method of increasing efficiency in Kaplan-type turbine. The method is based on blade profile optimisation together with modelling the interaction between rotor and stator blades. Loss coefficient was chosen as the optimisation criterion, which is related directly to efficiency. Global optimum was found by means of Genetic Algorithms, and Artificial Neural Networks were utilised for approximations to reduce...
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Pressure Pulsations in Turbine Blade Seal
PublicationThe paper presents the results of experimental investigations into pressure forces generated in a turbine labyrinth seal. The experiments were performed on a single-stage air model turbine of the impulse type. The performed experimental research proved that in a shroud clearance the pressure pulsates and the effects of the nozzle trailing edge thickness as well as the influence of the rotor blades are observed. The exemplary results...
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Some new soliton solutions to the higher dimensional Burger–Huxley and Shallow water waves equation with couple of integration architectonic
PublicationIn this paper, we retrieve some traveling wave, periodic solutions, bell shaped, rational, kink and anti-kink type and Jacobi elliptic functions of Burger’s equation and Shallow water wave equation with the aid of various integration schemes like improved -expansion scheme and Jacobi elliptic function method respectively. We also present our solutions graphically in various dimensions.
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Kerogen to bitumen transformation with respect to host rock environment
PublicationResearch focuses on analyzing the role of rock constituents in kerogen transformation. It includes mineral and organic matter characterization, kerogen and bitumen isolation, quantification, and determination of the critical factors of transformation ratio concerning generating mobile versus less mobile hydrocarbons. The results indicate that the ratio mainly depends on the distribution and type of kerogen in the basin, and secondly...
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Sensorless Control of Induction Machine Supplied by Current Source Inverter
PublicationThe paper describes the voltage control technique of induction machines supplied by a current source inverter. The control system is based on proposed new multi-scalar variables, which are named “r.” The control system contains the output filter capacitor's model. In the sensorless control system the Z type backstepping speed observer was applied. The mathematical dependences are confirmed by simulation and experimental research.
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Efficient Complex Root Finding Algorithm for Microwave and Optical Propagation Problems
PublicationArticle relates to the use of innovative root finding algorithm (on a complex plane) to study propagation properties of microwave and optical waveguides. Problems of this type occur not only in the analysis of lossy structures, but also in the study of complex and leaky modes (radiation phenomena). The proposed algorithm is simple to implement and can be applied for functions with singularities and branch cuts in the complex plane...
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A concept of measurement system based on the Z-Wave standard
PublicationIn the paper a new concept of measurement system based on the Z-Wave standard is presented. This standard is dedicated to use mainly in home automation systems, but its properties enable to use it in dispersed measurement systems and support wireless communication between measurement nodes in a mesh-type network. In the paper basic metrological aspects of the Z-Wave standard and an example of impedance measurement system are discussed.
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Dynamiczna aplikacja Internetowa ASP.NET silnika indukcyjnego jako elementu wirtualnego laboratorium maszyn elektrycznych
PublicationTematem referatu jest dynamiczna aplikacja internetowa, która umożliwia symulację obwodową silnika indukcyjnego trójfazowego Sg 100 L2 z wykorzystaniem interfejsu przeglądarki WWW. Model matematyczny silnika jest zdefiniowany w tzw. osiach naturalnych i sformułowany na podstawie metody energetycznej Lagrange’a. Do implementacji modelu maszyny w aplikacji internetowej wybrano projekt typu Web Forms, który jest składnikiem środowiska...
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Superconductivity in CaBi2
PublicationSuperconductivity is observed with critical temperature Tc = 2.0 K in self-flux-grown single crystals of CaBi2. This material adopts the ZrSi2 structure type with lattice parameters a = 4.696(1) Å, b = 17.081(2) Å and c = 4.611(1) Å. The crystals of CaBi2 were studied by means of magnetic susceptibility, specific heat and electrical resistivity measurements. The heat capacity jump at Tc is DC/gTc = 1.41, confirming bulk superconductivity;...