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Search results for: GAMMA ABSORPTION TECHNIQUE
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Geographic information system for remote integration of diverse under-water acoustic sensor data
PublicationMaritime and port areas throughout the world are exposed to many different hazards, like pollution, terrorism and natural disasters. Early detection, identification and preparation of appropriateesponse strategies is especially important in the case of semi-enclosed basins like the Baltic Sea, mainly due to the marine ecosystems' continuous absorption of pollutants including oil, heavy metals and chemicals. Many of those agents...
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Photophysics of Soret-Excited Tin(IV) Porphyrins in Solution
PublicationThe photophysics of low-chlorin tin(IV) tetraphenylporphyrin dihydroxide, a core building block for axially substituted supramolecular tin porphyrin constructs, has been studied in a variety of hydrogen-bonding, nonpolar, and aprotic polar solvents using steady-state, nanosecond, and femtosecond time-resolved emission, and femtosecond time-resolved absorption methods. In hydrogen-bonding solvents the metalloporphyrin exists as...
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Optoelectronic device for hematocrit measurements
PublicationAn optoelectronic system for measurements of hematocrit level (HCT) in the whole human blood is presented. Proposed system integrates a dedicated optoelectronic sensor, a microcontroller and a small LCD display in a low cost, battery-powered, handheld device. Chosen method for determining blood hematocrit level is based on optical properties of whole blood in visible and NIR wavelength range. Measurements with the use of proposed...
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Sodium alginate decreases the permeability of intestinal mucus
PublicationIn the small intestine the nature of the environment leads to a highly heterogeneous mucus layer primarily composed of the MUC2 mucin. We set out to investigate whether the soluble dietary fibre sodium alginate could alter the permeability of the mucus layer. The alginate was shown to freely diffuse into the mucus and to have minimal effect on the bulk rheology when added at concentrations below 0.1%. Despite this lack of interaction...
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Self-Association of Amphotericin B: Spontaneous Formation of Molecular Structures Responsible for the Toxic Side Effects of the Antibiotic
PublicationAmphotericin B (AmB) is a lifesaving antibiotic used to treat deep-seated mycotic infections. Both the pharmaceutical activity and highly toxic side effects of the drug rely on its interaction with biomembranes, which is governed by the molecular organization of AmB. In the present work we present detailed analysis of self-assembly of AmB molecules in different environments, interesting from the physiological standpoint, based...
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Ultrafast Intramolecular Relaxation and Wave-Packet Motion in a Ruthenium-Based Supramolecular Photocatalyst
PublicationThe hydrogen-evolving photocatalyst [(tbbpy)2 Ru(tpphz)Pd(Cl)2 ](2+) (tbbpy=4,4'-di-tert-butyl-2,2'-bipyridine, tpphz=tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]phenazine) shows excitation-wavelength-dependent catalytic activity, which has been correlated to the localization of the initial excitation within the coordination sphere. In this contribution the excitation-wavelength dependence of the early excited-state relaxation...
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Photophysics of Ru(II) Dyads Derived from Pyrenyl-Substitued Imidazo[4,5-f][1,10]phenanthroline Ligands.
PublicationThe photophysics of a series of Ru(II) dyads based on the 2-(1-pyrenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline ligand was investigated. The ability of these metal complexes to intercalate DNA and induce cell death upon photoactivation makes them attractive photosensitizers for a range of photobiological applications, including photodynamic therapy. In the present study, time-resolved transient absorption and emission spectroscopy...
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Properties of Thermally Dewetted Thin Au Films on ITO-Coated Glass for Biosensing Applications
PublicationNoble metal nanostructures are object of great interest due to their unique optical and electronic properties exploited in nanotechnology, medicine, biochemistry, and surface-enhanced spectroscopies. In this work, the Au nanoparticle (NP) structures for application in biosensing obtained by dewetting are investigated in dependence on their preparation conditions. Structures are produced from thin Au films (5–30 nm) sputtered onto...
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Precipitation of Spherical Vaterite Particles via Carbonation Route in the Bubble Column and the Gas-Lift Reactor
PublicationSpherical vaterite particles were produced by carbonation of calcium chloride solution with addition of ammonia to facilitate CO2 absorption. Synthesis of calcium carbonate was carried out in a bubble column or gas-lift reactor. The course of the reaction was monitored by pH measurements. Precipitated solids were analyzed by Fourier-transformed infrared spectroscopy, x-ray powder diffraction and scanning electron microscopy, and...
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Photoluminescence of partially reduced Eu2+/Eu3+ active centers in a NaF–Al2O3–P2O5 glassy matrix with tunable smooth spectra
PublicationIn 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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Fast-response optoelectronic detection of explosives’ residues from the nitroaromatic compounds detonation: field studies approach
PublicationWe are presenting an application of optoelectronic nitrogen dioxide (NO2) analyzer based on cavity enhanced absorption spectroscopy in the detection of traces of explosives after detonation. It has been shown that the analyzer using blue-violet laser is able to detect explosive residues after the detonation of various amounts of nitroaromatic compounds (75g-1kg) with higher efficiency than the HPLC soil sample testing equipment,...
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Laser induced formation of copper species over TiO2 nanotubes towards enhanced water splitting performance
PublicationWe proposed fast and scalable route where the ordered TiO2 nanotubes coated with thin copper layers were annealed by the laser beam of 355 nm wavelength at different fluencies in the range of 15–120 mJ/cm2. As a result, copper species are integrated with the titania substrate and the formed material exhibits unique optical absorption bands in the visible range. Moreover, X-ray photoelectron spectroscopy analysis reveals the formation...
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Light-Modulated Sunscreen Mechanism in the Retina of the Human Eye
PublicationThe functioning of the human eye in the extreme range of light intensity requires a combination of the high sensitivity of photoreceptors with their photostability. Here, we identify a regulatory mechanism based on dynamic modulation of light absorption by xanthophylls in the retina, realized by reorientation of pigment molecules induced by trans–cis photoisomerization. We explore this photochemically switchable system using chromatographic...
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Metamaterial-Based Sub-Microwave Electromagnetic Field Energy Harvesting System
PublicationThis paper presents the comprehensive analysis of the sub-microwave, radio frequency band resonant metastructures’ electromagnetic properties with a particular emphasis on the possibility of their application in energy harvesting systems. Selected structures based on representative topologies of metamaterials have been implemented in the simulation environment. The models have been analyzed and their substitute average electromagnetic...
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Application of TOPSIS for Selection and Assessment of Analytical Procedures for Ibuprofen Determination in Wastewater
PublicationThis paper describes the possible implementation of the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) as green analytical chemistry metrics tools. TOPSIS is one of the multi-criteria decision analysis (MCDA) tools that is applied in the selection of the best alternative from many possible. In this case we have applied it to assess the nineteen analytical procedures for ibuprofen determination in wastewater...
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AFM-assisted investigation of conformal coatings in electronics
PublicationPurpose – This paper aims to presents a new method of investigation of local properties of conformal coatings utilized in microelectronics. Design/methodology/approach – It is based on atomic force microscopy (AFM) technique supplemented with the ability of local electrical measurements, which apart from topography acquisition allows recording of local impedance spectra, impedance imaging and dc current mapping. Potentialities...
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SURFACTANTS IN KLODNICA RIVER (KATOWICE, POLAND). PART II. QUATERNARY AMMONIUM COMPOUNDS
PublicationThe paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative...
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Comparison of different techniques for extracting Polychlorinated Biphenyls from bottom sediment samples using Isotope Dilution Mass Spectrometry
PublicationIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. The main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sediment reference material (METRANAL 2) with the use of different solvents (dichloromethane, hexane, and toluene); the process...
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A Review: Applications of the Spectral Finite Element Method
PublicationThe Spectral Finite Element Technique (SFEM) has Several Applications in the Sciences, Engineering, and Mathematics, which will be Covered in this Review Article. The Spectral Finite Element Method (SFEM) is a Variant of the Traditional Finite Element Method FEM that Makes use of Higher Order Basis Functions (FEM). One of the most Fundamental Numerical Techniques Employed in the Numerical Simulation is the SFEM, which Outperforms...
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A Study of Mutual Coupling Suppression between Two Closely Spaced Planar Monopole Antenna Elements for 5G New Radio Massive MIMO System Applications
Publication5G NR (new radio) introduces the concept of massive MIMO (multiple-input-multiple-output) technology, in which a larger number of antenna arrays are installed on the transceiver. Due to the increased number of antenna elements allocated close to each other (approximately at half-wavelength distance), mutual coupling becomes a serious problem leading to performance degradation of the MIMO communication system. In this communication,...
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Global Complex Roots and Poles Finding Algorithm in C × R Domain
PublicationAn algorithm to find the roots and poles of a complex function depending on two arguments (one complex and one real) is proposed. Such problems are common in many fields of science for instance in electromagnetism, acoustics, stability analyses, spectroscopy, optics, and elementary particle physics. The proposed technique belongs to the class of global algorithms, gives a full picture of solutions in a fixed region ⊂ C × R and...
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Multimodal analysis of traction forces and the temperature dynamics of living cells with a diamond-embedded substrate
PublicationCells and tissues are constantly exposed to chemical and physical signals that regulate physiological and pathological processes. This study explores the integration of two biophysical methods: traction force microscopy (TFM) and optically detected magnetic resonance (ODMR) to concurrently assess cellular traction forces and the local relative temperature. We present a novel elastic substrate with embedded nitrogen-vacancy microdiamonds...
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Adaptive identification of sparse underwater acoustic channels with a mix of static and time-varying parameters
PublicationWe consider identification of sparse linear systems with a mix of static and time-varying parameters. Such systems are typical in underwater acoustics (UWA), for instance, in applications requiring identi- fication of the acoustic channel, such as UWA communications, navigation and continuous-wave sonar. The recently proposed fast local basis function (fLBF) algorithm provides high performance when identi- fying time-varying systems....
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Image Segmentation of MRI image for Brain Tumor Detection
Publicationthis research work presents a new technique for brain tumor detection by the combination of Watershed algorithm with Fuzzy K-means and Fuzzy C-means (KIFCM) clustering. The MATLAB based proposed simulation model is used to improve the computational simplicity, noise sensitivities, and accuracy rate of segmentation, detection and extraction from MR...
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seafloor characterisation combined approach using multibeam sonar echo signal processing and image analysis
PublicationThe authors propose the approach to seafloor characterisation which relies on the combined, concurrent use of two different techniques: (i) multibeam sonar image analysis and (ii) multibeam seabed echoes processing. The first technique is based on constructing the grey-level sonar images of the seabed extracted from the echoes received in the consecutive soundings. Then, the set of parameters describing the local region of sonar...
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Frequency response spectra applied to assess efficiency of the training techniques
PublicationThe purpose of the research is to assess the increase of the muscle strength and power. Movement of the human body when the moving one impacts a stationary or moving body is taken under consideration. The waveform produced by an impact is transformed into frequency domain. The acceleration record is transformed as a complex spectrum, by the use of a Discrete Fourier Transformation. In this paper the applications of the discrete...
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LC-MS and LC-NMR as Complementary Techniques for the Determination of Pharmaceuticals in Dosage Formulations
PublicationPharmaceuticals contain not only pharmacologically active compounds but also a range of excipients. The danger exists that impurities may also be present in such drugs, which may adversely affect their efficacy and even endanger patient health and life. Monitoring the composition of pharmaceutical products is therefore essential. The trace amounts of such impurities in pharmaceuticals are often identified and determined with liquid...
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Integrating Experience-Based Knowledge Representation and Machine Learning for Efficient Virtual Engineering Object Performance
PublicationMachine learning and Artificial Intelligence have grown significant attention from industry and academia during the past decade. The key reason behind interest is such technologies capabilities to revolutionize human life since they seamlessly integrate classical networks, networked objects and people to create more efficient environments. In this paper, the Knowledge Representation technique of Set of Experience...
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Shape and force control of cable structures with minimal actuators and actuation
PublicationShape adjustment and stress control can be considered as one of the effective parameters in prestressed cable structures since such structures are widely constructed nowadays due to their characteristics. The assembly errors and applied loads hugely affect the cables’ nodal positions and stress due to their delicacy. The former could disturb the shape, which affects the appearance and the function of the structure. In contrast,...
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Experience Based Decisional DNA (DDNA) to Support Sustainable Product Design
PublicationThis paper presents the idea of providing engineering design knowledge to designers working on sustainable product design and development process. The new product development process often requires significant amount of design knowledge which can be saved and recalled by designers during the design process. This knowledge is very important for successful sustainable product development as it can include material selection, product...
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Machine Learning and Electronic Noses for Medical Diagnostics
PublicationThe need for noninvasive, easy-to-use, and inexpensive methods for point-of-care diagnostics of a variety of ailments motivates researchers to develop methods for analyzing complex biological samples, in particular human breath, that could aid in screening and early diagnosis. There are hopes that electronic noses, that is, devices based on arrays of semiselective or nonselective chemical sensors, can fill this niche. Electronic...
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Ion Chromatography with Pulsed Amperometric Detection for Determining Cyanide in Urine and Meconium Samples
PublicationThe parents’ addictions and eating habits have a significant influence on the child’s growth. The first stool of a newborn baby provides a large amount of information about xenobiotics transmitted by the mother’s body. The analytical technique used in the study is ion chromatography with pulsed amperometric detection (IC-PAD). The biological samples, which were obtained from women staying in a maternity ward and their partners,...
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UHF ESPAR antenna for simple Angle of Arrival estimation in UHF RFID applications
PublicationAn electronically switched beam antenna for localization of passive UHF RFID tags based on a simple Angle of Arrival (AoA) technique is proposed‥ Detailed antenna design and realization are presented together with corresponding simulations and measurement results. Experimental tests with passive UHF RFID tag show the validity of theoretical assumptions for application of the antenna in UHF RFID based localization systems.
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Rapid design optimization of compact couplers using response features and adjoint sensitivities
PublicationA technique for rapid EM-driven design optimization of compact microwave couplers is presented. Our approach exploits response features and adjoint sensitivities and allows for low-cost design closure both in terms of performance enhancement and structure miniaturization. It is demonstrated using a compact rat-race coupler working at 1 GHz and compared to adjoint-based gradient optimization.
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New method of IEEE 802.15.4a UWB Impulse Radio Spectrum Shaping
PublicationThis paper presents a new technique of IEEE 802.15.4a ultra-wideband signal spectrum control, based on changes in sequences of transmitted pulses with very short duration time. Basic parameters of UWB signal and outline of proposed spectrum shaping methods are briefly described. The main part of the paper presents influence of signal and algorithms parameters on the results of spectrum shaping.
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A New Quaternion Encryption Scheme for Image Transmission
PublicationQuaternions are hypercomplex number of rank 4. They are often applied to mechanics in three-dimensional space and considered as one of the best ways to represent rotations. In this paper a new encryption scheme, based on the rotation of data vector in three-dimensional space around another quaternion (key) is proposed. A computer-based simulation was created to analyze the potential of the proposed encryption technique.
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Monotone iterative method for first-order differential equations at resonance
PublicationThis paper concerns the application of the monotone iterative technique for first-order differential equations involving Stieltjes integrals conditions. We discuss such problems at resonance when the measure in the Stieltjes integral is positive and also when this measure changes the sign. Sufficient conditions which guarantee the existence of extremal, unique and quasi-solutions are given. Three examples illustrate the results.
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OPTIMIZATION OF NASICON PREPARATION METHOD
PublicationNasicon is a solid conductor which has an ability to conduct Na+ ions and it is used in solid gas sensors. In this article a method of Nasicon preparation appropriate for gas sensing application by solgel technique is presented. Influence of the fabrication process parameters on properties of obtained samples was determined. Results of X-Ray diffraction, density, porosity, conductivity, and activation energies measurement are presented.
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ART WORKSHOP PLEIN AIR
e-Learning CoursesART WORKSHOP PLEIN AIR Outdoor classes in the field of painting for students of the first year of the Faculty of Architecture are aimed at shaping basic painting skills. Students continue to learn the basics of the tempera painting technique, which they learned in the second semester. Learning the basics of the painting workshop is carried out by looking for combinations of forms, mutual color relationships and the influence...
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Macromodels for Efficient Analysis of Open-Region Problems Using the Finite Element Method
PublicationThis paper presents a local model-order reduction, called macromodeling, applied to speed-up the simulations of open-region problems, analyzed by means of finite element method. This technique is illustrated by a numerical example, which deals with a dielectric resonator antenna (DRA). The obtained results show that the proposed approach is reliable and can significantly increase the standard finite element method efficiency.
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The energy consumption during the birch tree sap concentration process using the reverse osmosis system
PublicationBirch tree sap was concentrated by mens of the reversed osmosis technique. The energy consumption in a small-scale pilot apparatus was estimated. The threshold value for the water removal above which the specific energy consumption significantly increased was identified. Below the threshold value the reversed osmosis had low energy demand and could be an attractive method for the production of birch tree sap-based beverages.
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Resonant Frequencies in the Open Microstrip Structures Placed on Curved Surfaces
PublicationThe paper presents the research on open microstrip structures placed on curved surfaces such as cylindrical, elliptical or spherical. The numerical analysis of investigated structures is based on expansion of electric and magnetic fields into suitable function series. Utilizing the continuity conditions the boundary problem is formulated which is solved with the use of method of moments. The investigated structures find application...
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Green Analytical Chemistry Approaches in Sample Preparation
PublicationThis chapter presents environmentally friendly solutions for sample preparation. Attention is focused on extraction techniques and the minimization of organic solvent consumption, as the large quantitiesused in analytical laboratories are a pressing environmental problem. Solventless sample preparation techniques, alternative solvents, mediated extractions are discussed. The principle of each technique isbriefly described, together...
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Non-intrusive infrared-free eye tracking method
PublicationIn the paper a technique of eye tracking based on visible light is presented. The approach described does not require an additional hardware equipment used in the infrared eye tracking system. First, examples of existing eye tracking techniques were presented. Then, the proposed algorithm of image processing and the process of determining the eye position are described. The engineered eye tracking application was tested and the...
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Time-domine Dipole Fields in acoustic and Elektromagnetics
PublicationThe ultrawideband (UWB) radio technique presents a challenge not just for technology. The UWB carrier-free pulses act at a close distance, their electromagnetic fields being very different from classic monochromatic plane wave. The author proposes to adapt a time-domian approach to analysis of broadband spherical fields, both acoustic and electromagnetic, in fundamental cases of quasi-point physical sources.
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Green function diagonal for a class of heat equations
PublicationA construction of the heat kernel diagonal is considered as element of generalized zeta function theory, which gradient at the origin defines determinant of a differential operator in a technique for regularizing quadratic path integral. Some classes of explicit expressions of the Green function in the case of finite-gap potential coefficient of the heat equation are constructed. An algorithm and program for Mathematica are presented...
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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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A Self-Adaptive Complex Root Tracing Algorithm for the Analysis of Propagation and Radiation Problem
PublicationAn improved complex root tracing algorithm for radiation and propagation issues is proposed. The approach is based on a self-adaptive discretization of Cauchy’s argument principle for a C × R space and requires a reduced number of function calls in comparison to other procedures presented in the literature. A few different examples concerning propagation and radiation problems have been considered to verify the validity and efficiency...
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LCT, PIV and IR Imaging Detection in Selected Technical and Biomedical Applications
PublicationPaper presents the brief summary of the history of Thermochromic liquid crystals (TLC), Particle Image Velocimetry (PIV) and Infrared Imaging Themography (IR). Principal methods and tools are described and some examples are presented. With this objective, a new experimental technique have been developed and applied to the study of heat and mass transfer and for biomedical diagnosis. Selected results of experiments using these methods...
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E-MEDIACJE JAKO PRZEDSIĘBIORCZA STRATEGIA ROZWIĄZYWANIA KONFLIKTÓW = E-mediation – the entrepreneurial strategy of conflict resolution
PublicationArtykuł dotyczy tematu e-mediacji, które są nowoczesną metodą rozwiązywania konfliktów gospodarczych, zakładającą zastosowanie innowacyjnych rozwiązań informatycznych w procesie zarzadzania konfliktem. Zaprezentowano wyniki badań, które przeprowadzono na grupie polskich przedsiębiorców, by zweryfikować postawy wobec e-mediacji i gotowość korzystania z tego rozwiązania w sytuacjach konfliktowych.