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INTER-LAYER SHARING OF BACKUP PATH CAPACITIES PROVIDING FAST SERVICE RECOVERY IN IP-MPLS/WDM NETWORKS
PublikacjaIn this paper, we investigate the issue of providing the transmission continuity in IP-MPLS/WDM networks in the presence of failures of nodes/links. Special focus is put on assuring fast restoration of flows affected after a failure in a scenario assuming sharing the backup path capacities in order to decrease the overall bandwidth consumption. In particular, we propose a new approach to inter-layer sharing of link capacity reserved...
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Design of Frequency-Reconfigurable Branch-Line Crossover Using Rectangular Dielectric Channels
PublikacjaThis paper presents an efficient yet straightforward passive reconfiguration technique to tune the operating frequency of a branch-line crossover (BLCO). The underlying principle is to fill rectangular dielectric channels (RDCs) prepared beforehand with either air or materials of different relative permittivity. Two configurations (one RDC and three RDCs in each arm) of the branch-line crossover are employed to estimate the tunability...
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Cellular network quality evaluation at a university campus on the eve of 5G
PublikacjaThanks to the availability of mobile devices and the spread of broadband access around the world, the number of network users continues to grow. This has raised user awareness when it comes to the quality of content they consume. Many service providers and operators focus on monitoring QoN (Quality of Network) and QoS (Quality of Service) parameters, particularly those influenced by bandwidth and latency. However, for most end-users,...
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An Off-Body Narrowband and Ultra-Wide Band Channel Model for Body Area Networks in a Ferry Environment
PublikacjaIn the article an off-body narrowband and ultra-wide band channel model for Body Area Networks in a ferry environment is described. A mobile, heterogeneous measurement stand, that consists of three types of devices: miniaturized mobile nodes, stationary reference nodes and a data acquisition server was developed. A detailed analysis of both radio channels parameters in untypical indoor environment was carried out. An analysis of...
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An Off-Body Narrowband and Ultra-Wide Band Channel Model for Body Area Networks in a Ferryboat Environment
PublikacjaIn the article an off-body narrowband and ultra-wide band channel model for body area networks in a ferryboat environment is described. Considering the limited number of publications there is a need to develop an off-body channel model, which will facilitate the design of radio links, both from the multimedia services provider and the security point of view, for body area networks in this atypical environment. A mobile heterogeneous...
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In-situ odd random phase electrochemical impedance spectroscopy study on the electropolymerization of pyrrole on iron in the presence of sodium salicylate – The influence of the monomer concentration
PublikacjaIn this work, the potentiostatic electropolymerization of polypyrrole (PPy) on iron in aqueous solution of sodium salicylate and pyrrole is studied in situ by odd random phase electrochemical impedance spectroscopy (ORP-EIS). The influence of the pyrrole concentration on the electrosynthesis process is investigated. The ORP-EIS technique ensures a reliable analysis of the PPy electrosynthesis on iron by means of an advanced data...
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The methodology of design of axial clearances compensation unit in hydraulic satellite displacement machine and their experimental verification
PublikacjaA new methodology of calculating the dimensions of the axial clearance compensation unit in the hydraulic satellite displacement machine is described in this paper. The methods of shaping the compensation unit were also proposed and described. These methods were used to calculate the geometrical dimensions of the compensation field in an innovative prototype of a satellite hydraulic motor. This motor is characterized by the fact...
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A method of determining and visualizing safe motion parameters of a ship navigating in restricted waters
PublikacjaThe paper presents a method of displaying ship collision avoidance information which is based on an unconventional Collision Threat Parameters Area (CTPA) technique. The solution presented here extends CTPA's functionality from past works by supporting navigation in restricted waters and handling ship domains analytically instead of numerically. It visualizes potential navigational threats as well as possible collision avoidance...
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an intelligent image processing sensor - the algorithm and the hardware implementation
PublikacjaW artykule przedstawiono algorytm przeznaczony do rozpoznawania obiektów ruchomych w obrazie do celu analizy ruchu pojazdów. Algorytm został zrealizowany w układzie FPGA.Ang.: This paper describes the idea and theimplementation of the robust algorithm dedicated toextraction of moving vehicles from real-time cameraimages for the evaluation of traffic parameters, suchas the number of vehicles, their direction of movementand their...
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Miniaturized passive emission test chamber for in-situ measurement of emissions of organic compounds
PublikacjaThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air (outdoor). One of the main groups of chemical compounds present in indoor air, with proven harmfulness to health,are volatile organic compounds (VOCs). VOCs present indoor comprise a wide variety of hydrocarbons and hydrocarbons derivatives including aliphatic, aromatics, alkylbenzens,...
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Laboratory investigation with subbottom parametric echosounder SES-2000 standard with an emphasis on reflected pure signals analysis
PublikacjaThe main goal of the paper is to describe correlations between measurements results of trials taken on Gulf of Gdańsk bottom sounded with parametric echosounder SES-2000 Standard and laboratory research where collected during survey sediments were measured. Stationary tests took place at Gdansk University of Technology where 30 meters long 1.8 meter deep and 3 meters wide water tank is located. Main lobe of antenna was directed...
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On local buckling of cold-formed channel members
PublikacjaThe paper deals with local buckling of the compressed flanges of cold-formed thin-walled channel beams subjected to pure bending or axially compressed columns. Arbitrarily shaped flanges of open cross-sections and the web-flange interactions are taken into account. Buckling deformation of a beam flange is described by displacement related to torsion of the flange about the line of its connection with the web. Total potential energy...
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Assessment of Lipophilicity Indices Derived from Retention Behavior of Antioxidant Compounds in RP-HPLC
PublikacjaReverse phase high pressure liquid chromatography was employed in order to evaluate the lipophilicity of antioxidant compounds from different classes, such as phenolic acids, flavanones, flavanols, flavones, anthocyanins, stilbenes, xantonoids, and proanthocyanidins. The retention time of each compound was measured using five different HPLC columns: RP18 (LiChroCART, Purosphere RP-18e), C8 (Zorbax, Eclipse XDBC8), C16-Amide (Discovery...
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On the Consumption of Multimedia Content Using Mobile Devices: a Year to Year User Case Study
PublikacjaIn the early days, consumption of multimedia content related with audio signals was only possible in a stationary manner. The music player was located at home, with a necessary physical drive. An alternative way for an individual was to attend a live performance at a concert hall or host a private concert at home. To sum up, audio-visual effects were only reserved for a narrow group of recipients. Today, thanks to portable players,...
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Indykatory mobilne GIS w analizie ruchu miejskiego
PublikacjaW ramach artykułu autorzy przedstawią możliwości monitorowania sytuacji komunikacyjnej miasta z wykorzystaniem autorskiego i dedykowanego systemu monitorowania ruchu w mieście, opartego o pakiet oprogramowania stacjonarnego i mobilnego przeznaczonego dla korporacji taxi. Celem publikacji jest przedstawienie założeń optymalnych i minimalnych do realizacji monitoringu ruchu w mieście. Przywołane zostaną autorskie próby wdrożeń rozwiązań...
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Triangulation-based Constrained Surrogate Modeling of Antennas
PublikacjaDesign of contemporary antenna structures is heavily based on full-wave electromagnetic (EM) simulation tools. They provide accuracy but are CPU-intensive. Reduction of EM-driven design procedure cost can be achieved by using fast replacement models (surrogates). Unfortunately, standard modeling techniques are unable to ensure sufficient predictive power for real-world antenna structures (multiple parameters, wide parameter ranges,...
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A Geometrically Simple Compact Wideband Circularly Polarized Antenna
PublikacjaA compact broadband wide-slot circular polarization (CP) antenna is proposed. An inverted L-shape parasitic strip at the open end of a microstrip line extension and a slot modification is applied to attain wideband CP. The advantage of this technique is simplicity which makes it readily re-designable for different frequency bands. To demonstrate the concept, three designs working at different frequencies are obtained. The redesign...
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Deep learning in the fog
PublikacjaIn the era of a ubiquitous Internet of Things and fast artificial intelligence advance, especially thanks to deep learning networks and hardware acceleration, we face rapid growth of highly decentralized and intelligent solutions that offer functionality of data processing closer to the end user. Internet of Things usually produces a huge amount of data that to be effectively analyzed, especially with neural networks, demands high...
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Overview of Approaches for Compensating Inherent Metamaterials Losses
PublikacjaMetamaterials are synthetic composite structures with extraordinary electromagnetic properties not readily accessible in ordinary materials. These media attracted massive attention due to their exotic characteristics. However, several issues have been encountered, such as the narrow bandwidth and inherent losses that restrict the spectrum and the variety of their applications. The losses have become the principal limiting factor...
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Sensitive simultaneous determination of 19 fluorobenzoic acids in saline waters by solid-phase extraction and liquid chromatography–tandem mass spectrometry
PublikacjaA solid-phase extraction (SPE) procedure using C18 stationary phase was optimized for the preconcentration of 19 fluorinated derivatives of benzoic acid (FBA): mono-, di-, tri-, and tetrafluorosubstituted in the ring, trifluoromethylbenzoic acid and 3,5-bistrifluoromethyl benzoic acid from undiluted salt-rich (>20%) reservoir waters. Quantitative (>90%) retention/elution of 16 out of 19 analyte compounds was achieved allowing a...
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Common methods for the chiral determination of amphetamine and related compounds II: Capillary electrophoresis and nuclear magnetic resonance
PublikacjaAmphetamine group and related ring-substituted substances are generally synthetic compounds, belonging to one of the most heavily abused drug groups in recent years. Some compounds in this class also originate from plants. Analysis of the enantiomers of AM-type compounds and metabolites is extremely important for a number of scientific disciplines. From studies of biological activity or mechanisms through determination of precursor...
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Evaluation of organic coatings condition with AFM-based method
PublikacjaThe paper presents an atomic force microscopy (AFM)-based approach to evaluation of local protective properties of organic coatings. Apart from topography, it provides local ac and dc characteristics of examined coating. The method consists in application of ac voltage perturbation signal between conductive AFM tip and coated metal substrate. The resulting current is used to determine local impedance characteristics. Both impedance...
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An investigation of selected monoaromatic hydrocarbons released from the surface of polystyrene lids used in coffee-to-go cups
PublikacjaA consumer trend towards the fast preparation of beverages has increased the popularity of hot beverages (especially coffee and tea) available in disposable containers called coffee-to-go cups with fitted polystyrene lids. Lids in contact with hot beverages may release low molecular weight organic compounds into the gaseous phase causing direct exposure of consumers to these compounds during drinking. The paper describes in detail...
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Hyperbolic heat conduction at a microscopic sliding contact with account of adhesion-deformational heat generation and wear
PublikacjaDifferent non-Fourier models were proposed to simulate temperatures in materials subjected to extremely fast thermal disturbances, when the speed of heat propagation should be concerned. The present study investigated temperature and heat balance at a microscopic sliding contact during a single frictional interaction based on the Cattaneo-Vernotte hyperbolic heat conduction equation. Two fundamental features of friction, namely,...
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Verification of Satellite Railway Track Position Measurements Making Use of Standard Co-Ordinate Determination Techniques
PublikacjaThe article presents the results of satellite railway track position measurements performed by a multidisciplinary research team, the members of which represented Gdansk University of Technology and Gdynia Maritime University. Measuring methods are described which were used for reconstructing the railway track axis position and diagnosing railway track geometry deformations. As well as that, the description of the novel method...
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Reducing the Uncertainty of the Moving Object Location Measurement with the Method of Quasi-Multiple Measurement in GNSS Technology in Symmetrical Arrangement
PublikacjaThe article presents a solution to the problem of limited accuracy of dynamic measurements performed with GNSS receivers. The proposed measurement method is a response to the needs related to the assessment of the measurement uncertainty of the position of the track axis of the rail transport line. However, the problem of reducing the measurement uncertainty is universal for many different situations where high accuracy of positioning...
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Design of a Multidomain IMS/NGN Service Stratum
PublikacjaThe paper continues our research concerning the Next Generation Network (NGN), which is standardized for delivering multimedia services with strict quality and includes elements of the IP Multimedia Subsystem (IMS). A design algorithm for a multidomain IMS/NGN service stratum is proposed, which calculates the necessary CSCF servers CPU message processing times and link bandwidths with respect to the given maximum values of mean...
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Diagonalized Macromodels in Finite Element Method for Fast Electromagnetic Analysis of Waveguide Components
PublikacjaA new technique of local model-order reduction (MOR) in 3-D finite element method (FEM) for frequency-domain electromagnetic analysis of waveguide components is proposed in this paper. It resolves the problem of increasing solution time of the reduced-order system assembled from macromodels created in the subdomains, into which an analyzed structure is partitioned. This problem becomes particularly relevant for growing size and...
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Evaluation of high-frequency roughness measurement errors for composite and ceramic surfaces after machining
PublikacjaPrecise characterisation of surface topography is of the greatest importance since many factors directly affect the accuracy of the whole measurement process. In this paper, the variety of surface topographies from machined composite and ceramic workpieces was studied with a special emphasis on the measurement results. Surfaces were subjected to the ground diamond, honing and milling processes. Measurement results were analysed...
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Rapid simulation-driven design of miniaturised dual-band microwave couplers by means of adaptive response scaling
PublikacjaOne of the major challenges in the design of compact microwave structures is the necessity of simultaneous handling of several objectives and the fact that expensive electromagnetic (EM) analysis is required for their reliable evaluation. Design of multi-band circuits where performance requirements are to be satisfied for several frequencies at the same time is even more difficult. In this work, a computationally efficient design...
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Numerically Efficient Miniaturization-Oriented Optimization of an Ultra-Wideband Spline-Parameterized Antenna
PublikacjaDesign of ultra-wideband radiators for modern handheld applications is a challenging task that involves not only selection of an appropriate topology, but also its tuning oriented towards balancing the electrical performance and size. In this work, a low-cost design of a compact, broadband, spline-parameterized monopole antenna has been considered. The framework used for the structure design implements trust-region-based methods,...
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An Innovative Antenna Array with High Inter Element Isolation for Sub-6 GHz 5G MIMO Communication Systems
PublikacjaA novel technique is shown to improve the isolation between radiators in antenna arrays. The proposed technique suppresses the surface-wave propagation and reduces substrate loss thereby enhancing the overall performance of the array. This is achieved without affecting the antenna’s footprint. The proposed approach is demonstrated on a four-element array for 5G MIMO applications. Each radiating element in the array is constituted...
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Asymmetrical-Slot Antenna with Enhanced Gain for Dual-Band Applications
PublikacjaDual-band operation is an important feature of antennas to be applied in modern communication systems. Although high gain of radiators is rarely of concern in urban areas with densely located broadcasting stations, it becomes crucial for systems operating in more remote environments. In this work, a dual-band antenna with enhanced bandwidth is proposed. The structure consists of a driven element in the form of an asymmetrical radiator/slot...
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Introduction to MIP synthesis, characteristics and analytical application
PublikacjaOne of the trends in analytical chemistry is associated with designing and developing new types of sample preparation techniques, which might significantly increase the efficiency and selectivity of the analytes isolation or/and preconcentration process. One of the most widely employed solutions are selective sorption materials, defined as molecularly imprinted polymers (MIPs), as well as the sorbents with the molecular fingerprint....
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A Method of Fast and Simultaneous Calibration of Many Mobile FMCW Radars Operating in a Network Anti-Drone System
PublikacjaA market for small drones is developing very fast. They are used for leisure activities and exploited in commercial applications. However, there is a growing concern for accidental or even criminal misuses of these platforms. Dangerous incidents with drones are appearing more often, and have caused many institutions to start thinking about anti-drone solutions. There are many cases when building stationary systems seems to be aimless...
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Mechatronic Design Towards Investigation of the Temporo-Mandibular Joint Behaviour
PublikacjaA significant problem of the temporo-mandibular joint (TMJ) research is lack of data concerning geometry and position of TMJ discs. It leads to necessity of developing a driving method of the process optimization, which is based on chosen techniques of mechatronic design. In particular, the latter concerns a technique of experimentally supported virtual prototyping. On this stage, the research is characterized by well-verified...
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Influence of Nitriding and Laser Remelting on Properties of Austenitic Stainless Steel Type X10CrNi18-8 and Cavitation Erosion Resistance
PublikacjaThe paper presents properties of surface layers. Surface layers were obtained by using low temperature glow–discharge nitriding process and laser remelting carried out on austenitic stainless steel type X10CrNi18-8. Investigations were done by using an Ultra Nanoindentation Tester (UNHT) in the Warsaw Institute of Fundamental Technological Research. The influence of the above mentioned...
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Entropy Measures in the Assessment of Heart Rate Variability in Patients with Cardiodepressive Vasovagal Syncope
PublikacjaSample entropy (SampEn) was reported to be useful in the assessment of the complexity of heart rate dynamics. Permutation entropy (PermEn) is a new measure based on the concept of order and was previously shown to be accurate for short, non-stationary datasets. The aim of the present study is to assess if SampEn and PermEn obtained from baseline recordings might differentiate patients with various outcomes of the head-up tilt test...
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Investigation of the electrochemical behaviour of AA1050 aluminium alloy in aqueous alkaline solutions using Dynamic Electrochemical Impedance Spectroscopy
PublikacjaThe paper presents the electrochemical behaviour of aluminium alloy AA1050 in aqueous alkaline media in the pH range 14–8.5. Electrochemical study was applied in order to obtain comprehensive information on the mechanism and kinetics of the process of anodic dissolution of aluminium, supplemented by monitoring of surface topography using an electron microscope. The corrosion rate of AA1050 increases with increasing concentration...
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A design framework for rigorous constrained EM-driven optimization of miniaturized antennas with circular polarization
PublikacjaCompact radiators with circular polarization are important components of modern mobile communication systems. Their design is a challenging process which requires maintaining simultaneous control over several performance figures but also the structure size. In this work, a novel design framework for multi-stage constrained miniaturization of antennas with circular polarization is presented. The method involves sequential optimization...
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3D Metamaterial Ultra-Wideband Absorber for curved surface
PublikacjaThis paper proposes a three-dimensional metamaterial absorber based on a resistive film patch array to develop a low-cost, lightweight absorber for curved surfaces. An excellent absorption over a large frequency band is achieved through two different yet controllable mechanisms; In the first mechanism, a considerable attenuation in the wave power is achieved via graphite resistive films. The absorption is then intensified through...
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Digital Transformation of Terrestrial Radio: An Analysis of Simulcasted Broadcasts in FM and DAB+ for a Smart and Successful Switchover
PublikacjaThe process of digitizing radio is far from over. It is an important interdisciplinary aspect, involving Big Data and AI (Artificial Intelligence) when it comes to classifying and handling content, and an organizational challenge in the Industry 4.0 concept. There exist several methods for delivering audio signals, including terrestrial broadcasting and internet streaming. Among them, the DAB+ (Digital Audio Broadcasting plus)...
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Overview of Metamaterials-Integrated Antennas for Beam Manipulation Applications: The Two Decades of Progress
PublikacjaMetamaterials (MMs) are synthetic composite structures with superior properties not found in naturally occurring materials. MMs have gained massive attention over the last two decades because of their extraordinary properties, such as negative permittivity and permeability. These materials enable many applications in communication subsystems, especially in the field of antenna design, to enhance gain, bandwidth, and efficiency,...
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Molecularly imprinted polymers applied in capillary electrochromatography and electrophoresis techniques
PublikacjaMolecularly imprinted polymers (MIPs) are synthetic materials with predetermined selectivity for a particular analyte or group of structure-linked chemicals which make them an ideal separation component. The process of developing and applying new types of MIPs in the field of environmental analytical chemistry has been broadly discussedi n many scientific studies in recent years. The use of new types of MIP sorbents as unique sorption...
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The emissions of monoaromatic hydrocarbons from small polymeric toys placed in chocolate food products
PublikacjaThe article presents findings on the emissions of selected monoaromatic hydrocarbons from children's toys placed in chocolate food products. The emission test system involved the application of a new type of microscale stationary emission chamber, μ-CTE™ 250. In order to determine the type of the applied polymer in the manufacture of the tested toys, Fourier transform infrared spectroscopy and thermogravimetric analysis coupled...
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Smooth least absolute deviation estimators for outlier-proof identification
PublikacjaThe paper proposes to identify the parameters of linear dynamic models based on the original implementation of least absolute deviation estimators. It is known that the object estimation procedures synthesized in the sense of the least sum of absolute prediction errors are particularly resistant to occasional outliers and gaps in the analyzed system data series, while the classical least squares procedure unfortunately becomes...
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Modelling of wastewater treatment plant for monitoring and control purposes by state - space wavelet networks
PublikacjaMost of industrial processes are nonlinear, not stationary, and dynamical with at least few different time scales in their internal dynamics and hardly measured states. A biological wastewater treatment plant falls into this category. The paper considers modelling such processes for monitorning and control purposes by using State - Space Wavelet Neural Networks (SSWN). The modelling method is illustrated based on bioreactors of...
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A System for Heart Sounds Classification
PublikacjaThe future of quick and efficient disease diagnosis lays in the development of reliable non-invasive methods. As for the cardiac diseases – one of the major causes of death around the globe – a concept of an electronic stethoscope equipped with an automatic heart tone identification system appears to be the best solution. Thanks to the advancement in technology, the quality of phonocardiography signals is no longer an issue. However,...
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Size-exclusion chromatography for the determination of the boiling point distribution of high-boiling petroleum fractions
PublikacjaThe paper describes a new procedure for the determination of boiling point distribution of high-boiling petroleum fractions using size exclusion chromatography with refractive index detector. Thus far, the determination of boiling range distribution by chromatography has been accomplished using simulated distillation with gas chromatography with the flame ionization detection. This study revealed that in spite of substantial differences...
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The Product of Matrix Metalloproteinase Cleavage of Doxorubicin Conjugate for Anticancer Drug Delivery: Calorimetric, Spectroscopic, and Molecular Dynamics Studies on Peptide–Doxorubicin Binding to DNA
PublikacjaMatrix metalloproteinases (MMPs) are extracellular matrix degradation factors, promoting cancer progression. Hence, they could provide an enzyme-assisted delivery of doxorubicin (DOX) in cancer treatment. In the current study, the intercalation process of DOX and tetrapeptide-DOX, the product of the MMPs' cleavage of carrier-linked DOX, into dsDNA was investigated using stationary and time-resolved fluorescence spectroscopy, UV-Vis...