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Wyniki wyszukiwania dla: COMMUTATION UNIT IN A MOTOR
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Inverse Flood Routing Using Simplified Flow Equations
PublikacjaThe paper considers the problem of inverse flood routing in reservoir operation strategy. The aim of the work is to investigate the possibility of determining the hydrograph at the upstream end based on the hydrograph required at the downstream end using simplified open channel flow models. To accomplish this, the linear kinematic wave equation, the diffusive wave equation and the linear Muskingum equation are considered. To achieve...
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Structure and transport properties of triple-conducting BaxSr1−xTi1−yFeyO3−δ oxides
PublikacjaIn this work, BaxSr1−xTi1−yFeyO3−δ perovskite-based mixed conducting ceramics (for x = 0, 0.2, 0.5 and y = 0.1, 0.8) were synthesized and studied. The structural analysis based on the X-ray diffraction results showed significant changes in the unit cell volume and Fe(Ti)–O distance as a function of Ba content. The morphology of the synthesized samples studied by means of scanning electron microscopy has shown different microstructures...
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Neural Approximators for Variable-Order Fractional Calculus Operators (VO-FC)
PublikacjaThe paper presents research on the approximation of variable-order fractional operators by recurrent neural networks. The research focuses on two basic variable-order fractional operators, i.e., integrator and differentiator. The study includes variations of the order of each fractional operator. The recurrent neural network architecture based on GRU (Gated Recurrent Unit) cells functioned as a neural approximation for selected...
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Power System Dynamics. Stability and Control. 3rd edition
PublikacjaComprehensive, state-of-the-art review of information on the electric power system dynamics and stability. It places the emphasis first on understanding the underlying physical principles before proceeding to more complex models and algorithms. The book explores the influence of classical sources of energy, wind farms and virtual power plants, power plants inertia and control strategy on power system stability. The book cover...
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Operational problems of large power diesel engines combusting biofuels, considered togetherwith assessment of their operation
PublikacjaWithin this article the issue of large power self ignition engines fed with biofuels has been undertaken. The analysis focused mainly on operation problems. There has been noticed some advantages and difficulties associated with the biofuel application to self ignition engines. The research problem has been characterised and the research purposes have been proposed enabling the most profitable formation of energetic features of...
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Evaluation of structural change during fast transformation process of cross-linked NR into liquid NR by light pyrolysis
PublikacjaThe presence of cross-linked networks in rubber creates a tremendous problem for recycling and reusing of waste rubber. Fast transformation of cross-linked natural rubber (NR) into liquid natural rubber was carried out by light pyrolysis in temperature range from 240 to 300 °C in variable time (in range: 1–30 min). The transformation efficiency was evaluated by measuring the sol fraction and the cross-link density of the gel fraction....
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Smart sustainable cities : Reconnaissance Study
PublikacjaThe global urban population is expected to grow by 63 percent between 2014 and 2050 – compared to an overall global population growth of 32 percent during the same period. Megacities with over 20-million inhabitants will see the fastest increase in population – and at least 13 new megacities are expected by 2030, in addition to the 28 existing today. The fastest growing urban centres contain around one-million inhabitants, and...
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No-Wait & No-Idle Open Shop Minimum Makespan Scheduling with Bioperational Jobs
PublikacjaIn the open shop scheduling with bioperational jobs each job consists of two unit operations with a delay between the end of the first operation and the beginning of the second one. No-wait requirement enforces that the delay between operations is equal to 0. No-idle means that there is no idle time on any machine. We model this problem by the interval incidentor (1, 1)-coloring (IIR(1, 1)-coloring) of a graph with the minimum...
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Measurement of luminance and color uniformity of displays using the large-format scanner
PublikacjaUniformity of display luminance and color is important for comfort and good perception of the information presented on the display. Although display technology has developed and improved a lot over the past years, different types of displays still present a challenge in selected applications, e.g. in medical use or in case of multi-screen installations. A simplified 9-point method of determining uniformity does not always produce...
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Advantageous conditions of saccharification of lignocellulosic biomass for biofuels generation via fermentation processes
PublikacjaProcessing of lignocellulosic biomass includes four major unit operations: pre-treatment, hydrolysis, fermentation and product purifcation prior to biofuel generation via anaerobic digestion. The microorganisms involved in the fermentation metabolize only simple molecules, i.e., monosugars which can be obtained by carrying out the degradation of complex polymers, the main component of lignocellulosic biomass. The object of this...
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The new concept of capillary forces aided evaporator for application in domestic organic rankine cycle
PublikacjaThis paper presents studies on the possibility of applying capillary forces induced in the porous structure to a modern design of evaporator. The potential application of such heat exchanger is for example an evaporator of the domestic micro combined heat and power (CHP) unit. One of the problems in the micro-CHP is excessive demand for pumping power. The proposed design helps in overcoming that issue. In the evaporator outlined...
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Possibility to use engine compression ignition engines in floating power plants marine
PublikacjaCompression-ignition engines used in ship technology as main propulsion engines are large units reaching even to 50-60 MW. The engines can be used in power industry for electricity generation in a simple or combined steam turbine system in combined heat and power plants. The leading engine in such an arrangement is an internal-combustion piston engine. The main propulsion engines are used in large piston internal-combustion engines...
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Feasibility of combined diesel engine - steam turbine in power station operating in the maritime
PublikacjaCompression-ignition engines used in ship technology as main propulsion engines are large units reaching even to 50-60 MW. Currently, the efficiency of such engines amounts to 45-50%. With such a large power unit, exhaust gases leaving the engine contain very large quantities of heat available for further treatment. Exhaust gases from the piston engine contain about 25% of the heat supplied to the engine in the fuel. Using the...
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Stability evaluation of the marine propulsion unit's mechanical system by means of vibration measurements and their analysis
PublikacjaIn this paper selected issues concerning vibration diagnosis of the mechanical system within marine propulsion units have been given. The analysis of vibration parameters was carried out on the basis of experimental examinations of a real object in which an exceedance of the allowable vibration's level had been observed. In the beginning, the vibration apparatus being on laboratory equipment of the Department of Ship Power Plants...
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Postquarter-Point Case of Ship’s Side-Berthing and Its Influence on Marine Fender Pitch
PublikacjaThis paper presents a critical analysis of some selected codes and practical recommendations used as basic rules in the design procedures of modern marine fender systems. The first part of the discussion pertains to the existing equations used in calculating the eccentricity coefficient in the ship’s kinetic energy equation and the maximum allowable fender pitch (spacing) in a set of fenders installed along a quay wall. A new approach...
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Efficiency of Artificial Intelligence Methods for Hearing Loss Type Classification: an Evaluation
PublikacjaThe evaluation of hearing loss is primarily conducted by pure tone audiometry testing, which is often regarded as golden standard for assessing auditory function. If the presence of hearing loss is determined, it is possible to differentiate between three types of hearing loss: sensorineural, conductive, and mixed. This study presents a comprehensive comparison of a variety of AI classification models, performed on 4007 pure tone...
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3-D Printable Metal-Dielectric Metasurface for Risley Prism-Based Beam-Steering Antennas
PublikacjaA 3-D printable, planar, metal-dielectric metasurface-based, 2-D beam-steering system for aperture-type antennas is presented in this paper. This beam steering system, also known as the near-field meta-steering system, comprises two fully passive phase-gradient metasurfaces placed in the antenna’s nearfield region to steer the radiation beam. To address the non-uniform electric field phase of the aperture antenna, phase correction...
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Reactivity of Phosphanylphosphinidene Complex of Tungsten(VI) toward Phosphines: A New Method of Synthesis of catena-Polyphosphorus Ligands
PublikacjaThe reactivity of an anionic phosphanylphosphinidene complex of tungsten(VI), [(2,6-i-Pr2C6H3N)2(Cl)- W(η2-t-Bu2P=P)]Li·3DME toward PMe3, halogenophosphines, and iodine was investigated. Reaction of the starting complex with Me3P led to formation of a new neutral phosphanylphosphinidene complex, [( 2,6-i-Pr2C6H3N)2(Me3P)W(η2-t-Bu2P=P)]. Reactions with halogenophosphines yielded new catena-phosphorus complexes. From reaction with...
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Efficient algorithm for blinking LED detection dedicated to embedded systems equipped with high performance cameras
PublikacjaThis paper presents the concept and implementation of an efficient algorithm for detection of blinking LED or similar signal sources. Algorithm is designed for embedded devices equipped with high performance cameras being a part of an indoor positioning embedded system. An algorithm to be implemented in such a system should be efficient in terms of computational power what is hard to be achieved when large amount of data from camera...
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An Intelligent Approach to Short-Term Wind Power Prediction Using Deep Neural Networks
PublikacjaIn this paper, an intelligent approach to the Short-Term Wind Power Prediction (STWPP) problem is considered, with the use of various types of Deep Neural Networks (DNNs). The impact of the prediction time horizon length on accuracy, and the influence of temperature on prediction effectiveness have been analyzed. Three types of DNNs have been implemented and tested, including: CNN (Convolutional Neural Networks), GRU (Gated Recurrent...
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Pluralist View on Inequality from Luxemburg Income Study (LIS)
PublikacjaThe authors start by reviewing the history of the Luxembourg Income Study (LIS), originating from an interdisciplinary project involving economists, sociologists, and political scientists, centered on the cross-country perspective in inequality analysis. They then conduct a meta-analysis of the papers produced by scholars who have taken advantage of the data availability, showing how the theme of income/wealth inequality has been...
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Voltage fluctuations on the main switchgear of the industrial power system supplying the rolling mill motors_part_2
Dane BadawczeThe dataset presents the voltage waveforms on the bus bars of the main switchgear of the industrial power network for the supply of rolling mills. The data was recorded during an experiment whose purpose was to determine a level of short-term and long-term flicker caused by voltage fluctuations. In the virtual application of flickermeter, a hardware...
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Funkcjonowanie zespołów napędu hydraulicznego maszyn w niskich temperaturach otoczenia
PublikacjaW pracy przedstawiono cztery warianty klasyfikacji rozruchów oziębionego napędu hydraulicznego. Pierwsza sytuacja dotyczy zagadnienia, w którym wszystkie zespoły układu napędowego wraz z olejem mają taką samą niską temperaturę podczas rozruchu. Pozostałe warianty odnoszą się do rozruchu w warunkach szoku termicznego wywołanych zasilaniem ciepłym czynnikiem roboczym oziębionych zespołów hydraulicznych. Rozruch zespołów...
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WYDATKI INWESTYCYJNE WOJEWÓDZTW SAMORZĄDOWYCH PO WPROWADZENIU INDYWIDUALNEGO WSKAŹNIKA ZADŁUŻENIA
PublikacjaOkreślenie dopuszczalnego poziomu zadłużenia jest ważną kwestią dla każdej jednostki samorządu terytorialnego w Polsce, a jej ranga jeszcze rośnie, jeśli samorząd odczuwa silną presję na dbanie o rozwój obszaru, na którym funkcjonuje, borykając się równocześnie z niedostatkiem dochodów. Taka sytuacja dotyczy większości województw samorządowych, które spośród wszystkich szczebli struktury samorządowej...
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A Data Driven Model for Predicting RNA-Protein Interactions based on Gradient Boosting Machine
PublikacjaRNA protein interactions (RPI) play a pivotal role in the regulation of various biological processes. Experimental validation of RPI has been time-consuming, paving the way for computational prediction methods. The major limiting factor of these methods has been the accuracy and confidence of the predictions, and our in-house experiments show that they fail to accurately predict RPI involving short RNA sequences such as TERRA RNA....
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Superconductivity in Metal-Rich Chalcogenide Ta2Se
PublikacjaThe metal–metal bond in metal-rich chalcogenide is known to exhibit various structures and interesting physical properties. Ta2Se can be obtained by both arc-melting and solid-state pellet methods. Ta2Se crystallizes a layered tetragonal structure with space group P4/nmm (No. 129; Pearson symbol tP6). Each unit cell consists of four layers of body-centered close-packing Ta atoms sandwiched between two square nets of Se atoms, forming...
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Retrievable strain measuring system in screw displacement piles - readings and results interpretation problems
PublikacjaStatic load tests on foundation piles are generally carried out in order to determine load – displacement characteristic of the pile. For more detailed information, e.g. force distribution along the shaft, load transfer mechanism and characteristics of soil-structure interaction (unit resistance curves t-z, q-z) additional pile instrumentation is required. Most popular techniques focus on direct concrete strain measurements and...
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Combined cold supply system for ship application based on low GWP refrigerants - Thermo-economic and ecological analyses
PublikacjaThe withdrawal of popular high-GWP refrigerants will significantly affect maritime industry. Refrigeration and air conditioning systems currently used on ships are not ready to fulfil future limitations. Therefore, there is a need for system, which will operate with low-GWP refrigerants and at the same time will be efficient and reliable in difficult environmental conditions. This paper explains the concept of a cold supply system,...
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Hierarchical dissolved oxygen control for activated sludge processes
PublikacjaA hierarchical controller for tracking the dissolved oxygen reference trajectory in activated sludge processes is proposed and investigated. The removal of nitrogen and phosphorous from wastewater is considered. Typically, an aeration system itself is a complicated hybrid nonlinear dynamical system with faster dynamics compared to the internal dynamics of the dissolved oxygen in a biological reactor. It is a common approach to...
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Process Control and Investigation of Oxidation Kinetics of Postoxidative Effluents Using Gas Chromatography with Pulsed Flame Photometric Detection (GC-PFPD)
PublikacjaThis article presents the results of investigations on the use of headspace analysis and gas chromatography with pulsed flame photometric detection (HSA-GC-PFPD) to evaluate the effectiveness of oxidation of postoxidative effluents from the production of bitumens. Samples of effluents from the bitumen oxidation unit were used in the experiments. In addition, the kinetics of effluent oxidation was also investigated. The content...
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The influence of screw configuration and screw speed of co-rotating twin screw extruder on the properties of products obtained by thermomechanical reclaiming of ground tire rubber
PublikacjaThe results of our investigations on the process of continuous thermomechanical reclaiming of ground tire rubber (GTR) carried out using a twin screw extruder are presented.We used a co-rotating twin screw extruder with a special configuration of plasticizing unit, enabling generation of considerable shear forces. The influence of screw configuration and screw speed on breaking of chemical crosslink bonds contained in ground tire...
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Elastic Fender-Dolphin Interaction for Economic Design of Berthing Dolphins
PublikacjaThe study addresses the question of the possible design benefits when considering the interaction between a modern marine modular rubber fender and a steel tubular pile substructure of a berthing dolphin. Absorption of the berthing kinetic energy of the vessel by a dualelasticity pile-fender berthing system is described in detail using the interactive treatment method (ITM). Application of the ITM is illustrated by a calculative...
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Investigation of the Combustion Processes in the Gas Turbine Module of an FPSO Operating on Associated Gas Conversion Products
PublikacjaIn this paper, we consider the issue of thermo-chemical heat recovery of waste heat from gas turbine engines for the steam conversion of associated gas for offshore vessels. Current trends in the development of offshore infrastructure are identified, and the composition of power plants for mobile offshore drilling units and FPSO vessels is analyzed. We present the results of a comparison of power-to-volume ratio, power-to-weight...
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The shallow sea experiment with usage of linear hydrophone array
PublikacjaPurpose of this article is to present designed and made linear hydrophone array and the results obtained during in situ trails on Gulf of Gdańsk. The measuring system allowed to localize hydrophones in the selected points and perform measurements in both the horizontal antenna positioning and vertical. Made in this way recordings allow creating accurate 3D imaging of sound intensity/propagation. During research three floating objects...
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The influence of feed rate and shear forces on the devulcanization process of ground tire rubber (GTR) conducted in a co-rotating twin screw extruder
PublikacjaThe search for new ways to recycling of rubber waste has been the aim of many studies conducted by research centers and companiesworldwide. The results of our investigations on the process of continuous thermomechanical devulcanization of ground tire rubber using a twin screw extruder are presented.We used a co-rotating twin screw extruder with a special configuration of plasticizing unit, enabling generation of considerable shear...
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Copper(I) halide cluster-based coordination polymers modulated by chiral ditopic dithiodianthranilide ligands: synthesis, crystal structure and photoluminescence
PublikacjaReaction of copper(I) halides with chiral dithiodianthranilidesmdtaandbdtaafforded polymeric complexeswhere polynuclear CuX clusters were linked together by ditopic bridging ligands into 1D chains or 2D layerstructures. In the case of racemic ligands double stranded chain polymers were formed where the Cu4X4(X = I or Br) cores are connected by enantiomeric pairs of the ditopic ligands. In contrast, a homochiralmdtaligand created...
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Experimental investigation on heat pipes supported by soy wax and lauric acid for electronics cooling
PublikacjaThis paper presents an experimental study of heat pipes for electronics cooling that were supported by energy storage materials (i.e. phase change materials - PCMs) coated at the adiabatic section. The PCMs utilized included two materials, namely lauric acid and soy wax, the latter being considered as a more cost-effective alternative. The study focused on three different powers: 20 W, 25 W, and 30 W. Both heating, cooling, and...
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Estimation of Screw Displacement Pile-Bearing Capacity Based on Drilling Resistances
PublikacjaThis article presents an engineering, empiricalmethod of estimating the bearing capacity and settlementcharacteristics Q-s of screw displacement piles andcolumns, based on soil resistance encountered during thedrilling to form piles/columns in the ground. The methodwas developed on the basis of correlation analyses of thetest results of 24 piles made during the “DPDT-Auger”research project (Krasiński et al., 2022a). In the proposedmethod,...
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Deformation of an elastic second gradient spherical body under equatorial line density of dead forces
PublikacjaWe consider deformations of an elastic body having initially a spherical shape. Assumed deformation energy depends on the first and second gradient of displacements. We apply an equatorial line density of dead loads, that are forces per unit line length directed in radial direction and applied along the equator of the sphere. We restrict ourselves our analysis to the case of linearized second strain gradient isotropic elasticity...
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An electric ring thruster as auxiliary manoeuvring propulsion system for watercraft - construction analysis
PublikacjaThe reported project aimed at examining properties and purposefulness of use of modern electromagneticbearings for a screw propeller in a prototype version of a synchronous ring motor with rare earths magnets.Bearings of this type generate electromagnetic forces which keep the rotor in a state of levitation. Therotating machine with magnetic bearings can work in any environment which reveals diamagnetic properties(air, vacuum,...
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Mechanochemical Energy Transduction during the Main Rotary Step in the Synthesis Cycle of F1-ATPase
PublikacjaF1-ATPase is a highly efficient molecular motor that can synthesize ATP driven by a mechanical torque. Its ability to function reversibly in either direction requires tight mechanochemical coupling between the catalytic domain and the rotating central shaft, as well as temporal control of substrate binding and product release. Despite great efforts and significant progress, the molecular details of this synchronized and fine-tuned...
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Microgrinding with single-disk lapping kinematics.
PublikacjaGrinding operations are carried out with a variety of tool-workpiece configurations. The selection of a grinding process for a particular application depends on part shape, part size, ease of fixture, requirements concerning the acceptable shape errors. It is evident that lapping is very effective in eliminating the waviness while surface grinding is not. Dual disk machines for the double face grinding with planetary kinematics...
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Diagnostyka łożysk silnika indukcyjnego na podstawie prądu zasilającego przy użyciu sztucznych sieci neuronowych
PublikacjaW artykule zawarto wyniki badań dotyczące diagnostyki łożysk silnika indukcyjnego na podstawie pomiarów prądu zasilającego z wyko-rzystaniem sztucznych sieci neuronowych. Zaprezentowano wyniki uczenia sieci oraz rezultaty testów przeprowadzonych na danych spoza zbioru uczącego. Badania wykonane zostały na obiektach z celowo wprowadzonymi uszkodzeniami łożysk. Przedstawiona nowa koncepcja zakłada użycie zestawu sieci neuronowych...
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Scheduling with Complete Multipartite Incompatibility Graph on Parallel Machines: Complexity and Algorithms
PublikacjaIn this paper, the problem of scheduling on parallel machines with a presence of incompatibilities between jobs is considered. The incompatibility relation can be modeled as a complete multipartite graph in which each edge denotes a pair of jobs that cannot be scheduled on the same machine. The paper provides several results concerning schedules, optimal or approximate with respect to the two most popular criteria of optimality:...
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Power Hardware-In-the-Loop Approach for Autonomous Power Generation System Analysis
PublikacjaThe article presents the Power Hardware-In-the-Loop (PHIL) dynamic model of a synchronous generator of 125 kVA for autonomous power generation system analysis. This type of system is typically composed of electrical energy sources in the form of several diesel generator units with synchronous machines, the main distribution switchboard and different loads. In modern power distribution systems, the proposed power management strategies...
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Detection of the Plant Pathogen Pseudomonas Syringae pv. Lachrymans on Antibody-Modified Gold Electrodes by Electrochemical Impedance Spectroscopy
PublikacjaThe present work describes an impedimetric immunosensor for Pseudomonas syringae pv. lachrymans (Psl) detection. This pathogen infects many crop species causing considerable yield losses, thus fast and cheap detection method is in high demand. In the assay, the gold disc electrode was modified with 4-aminothiophenol (4-ATP), glutaraldehyde (GA), and anti-Psl antibodies, and free-sites were blocked with bovine serum albumin (BSA)....
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Crystal structures of aminotransferases Aro8 and Aro9 from Candida albicans and structural insights into their properties
PublikacjaAminotransferases catalyze reversibly the transamination reaction by a ping-pong bi-bi mechanism with pyridoxal 5′-phosphate (PLP) as a cofactor. Various aminotransferases acting on a range of substrates have been reported. Aromatic transaminases are able to catalyze the transamination reaction with both aromatic and acidic substrates. Two aminotransferases from C. albicans, Aro8p and Aro9p, have been identified recently, exhibiting...
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Assessment of Supercapacitor’s Quality by Means of Low Frequency Noise
PublikacjaLow frequency noise is a well-known tool for quality and reliability assessment of electronic devices. This phenomenon is observed in different electrochemical devices as well (e.g., smart windows, electrochemical corrosion processes). Thus, we can assume that the same tool can be used to asses quality of supercapacitors. Their quality is usually determined only by capacitance and/or equivalent series resistance (ESR), or impedance....
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Evaluation of respiration capacity of VF in hybrid constructed wetland systems.
PublikacjaThree VF-beds operating in hybrid constructed wetlands in configuration HF-VF-HF were analysed. These hybrid constructed wetlands provide the II stage biological treatment. They are located in Pommerania voivodship, in Sarbsk, Wiklino and Wieszyno, and their capacities are 29.5, 14.2 and 21.6 m3/d, respectively. The article focuses on performance and operation of VF-CW plants during one year. Based on removal of organic matter...
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Testing Stability of Digital Filters Using Multimodal Particle Swarm Optimization with Phase Analysis
PublikacjaIn this paper, a novel meta-heuristic method for evaluation of digital filter stability is presented. The proposed method is very general because it allows one to evaluate stability of systems whose characteristic equations are not based on polynomials. The method combines an efficient evolutionary algorithm represented by the particle swarm optimization and the phase analysis of a complex function in the characteristic equation....