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The effectiveness of financial and economic regulation of land relations in the context of stimulating entrepreneurial activity in the regions of Ukraine
PublikacjaSolving the problem of enhancing the efficiency of the financial and economic regulation of land relations contributes to the development of entrepreneurship in Ukraine. The purpose of the paper is to determine new incentives for encouraging entrepreneurial activity by increasing the efficiency of the financial and economic regulation of land relations by local governments. The study is based on applying the method for predicting...
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Multiple Cues-Based Robust Visual Object Tracking Method
PublikacjaVisual object tracking is still considered a challenging task in computer vision research society. The object of interest undergoes significant appearance changes because of illumination variation, deformation, motion blur, background clutter, and occlusion. Kernelized correlation filter- (KCF) based tracking schemes have shown good performance in recent years. The accuracy and robustness of these trackers can be further enhanced...
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Experimental investigation of thermal energy storage in shell-and-multi-tube unit with nano-enhanced phase change material
PublikacjaThis 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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CAVER Analyst 1.0: graphic tool for interactive visualization and analysis of tunnels and channels in protein structures
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OPERATIONAL PROBLEMS OF CONSTRUCTED WETLAND FOR LANDFILL LEACHATE TREATMENT: CASE STUDY
PublikacjaThe present paper discusses the quality fluctuations of leachate from municipal landfill in Gdansk (Poland) over the last 5 years and the evaluation of a wetland system designed for treatment of the leachate. The research has been conducted during a 5-year period. The constructed wetland for leachate treatment was built in 2001; it consists of 2 horizontal subsurface flow reed beds, working in parallel. In the period 2005–2006...
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Bioterrorism — characteristics and possibilities of prevention
PublikacjaIn the paper bioterrorist threats have been presented. Historical background and possible methods of attacks have been described. The most dangerous pathogens and disease entities have been classified. Selected methods of detection and identification of biological weapon have been presented. The wireless system for threats monitoring — developed at Gdansk University of Technology — has been described.
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Overview of Scalability and Reliability Problem in SDN Networks
PublikacjaIn the paper an overview of scalability and reliability in the SDN (Software Defined Networks) networks has been presented. Problems and limitations for guaranteeing scalability and reliability in SDN networks have been indicated. Known methods for assuring scalability and reliability in SDN networks have been described. Projects from research communities for resolving issues with scalability and reliability in SDN networks have...
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Modeling process of planning finished product sales volumes at industrial enterprises in modern economic conditions
PublikacjaThis article presents improving the existing system of planning finished products sales volumes. The influencing factors of the sales volumes in modern economic conditions have been determined: falling world oil prices, the reduction of pipe consumption in the domestic market, the global pandemic. The algorithm of planning finished products sales volumes has been constructed. Calculations based on the Holt forecasting method has...
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Electrical and structural properties of Nb-doped SrTiO3
PublikacjaNiobium-doped strontium titanate synthesized via conventional solid-state reaction has been studied. Influence of niobium content on the lattice parameters and electrical conductivity has been reported. Various reduction conditions have been investigated. For samples reduced in hydrogen at 1400°C, a transition from thermally activated to metallic behavior has been observed. Maximum electrical conductivity (ca. 55 Scm−1 at 650°C)...
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Estimation of the angular position of a two-wheeled balancing robot using a real IMU with selected filters
PublikacjaA low-cost measurement system using filtering of measurements for two-wheeled balancing robot stabilisation purposes has been addressed in this paper. In particular, a measurement system based on gyroscope, accelerometer, and encoder has been considered. The measurements have been corrected for deterministic disturbances and then filtered with Kalman, α-β type, and complementary filters. A quantitative assessment of selected filters...
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Preliminary design of the last stage of supercritical steam turbine and proposition of anti-erosion coating for blades surface
PublikacjaIn this article a preliminary design of the last stage of supercritical steam turbine has been presented. A computational model of supercritical thermal cycle has been created in order to determine steam parameters at the stage inlet and outlet. The model was based on the structure of German coal-fired power plant Datteln 4. Further steam-flow parame-ters and dimensions of stator and rotor blades have been calculated analytically....
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Numerical and experimental propeller noise investigations
PublikacjaThe standard propeller has been investigated in model scale, using medium size cavitation tunnel. The hydroacoustic characteristics of propellers under different loading conditions have been investigated. Additionally the presented experimental results have been used for the verification of applied numerical approach. During both numerical and experimental analyses non-uniform inflow propeller’s conditions have been adapted. Good...
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Analysis of thoracic regional impedance changes using PCA approach
PublikacjaA multichannel impedance and one lead electrocardiographic recording system has been developed. The impedance measurement unit is built using a four-electrode technique. It consists of a sinusoidal, 40 kHz, current source and five measurement channels. Circumferential current electrodes have been located at a neck and an abdomen. Voltagemeasurement disk electrodes formed five two-electrode measurement ports. The impedance change...
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Collective citizens' behavior modelling with support of the Internet of Things and Big Data
PublikacjaIn this paper, collective human behaviors are modelled by a development of Big Data mining related to the Internet of Things. Some studies under MapReduce architectures have been carried out to improve an efficiency of Big Data mining. Intelligent agents in data mining have been analyzed for smart city systems, as well as data mining has been described by genetic programming. Furthermore, artificial neural networks have been discussed...
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Neural Networks, Support Vector Machine and Genetic Algorithms for Autonomous Underwater Robot Support
PublikacjaIn this paper, artificial neural networks, a classification technique called support vector machine and meta-heuristics genetic algorithm have been considered for development in autonomous underwater robots. Artificial neural networks have been used for seabed modelling as well as support vector machine has been applied for the obstacles classification to avoid some collision problems. Moreover, genetic algorithm has been applied...
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Towards Changes of Macro-Economic Structures in Middle Eastern Countries. Empirical Evidence for 1970–2018
PublikacjaMiddle East countries share a wide bundle of specific structural economic features and one of the latest is a high dependency of these economies on fossil fuels, which is quantitatively demonstrated through the share of oil and gas revenues in total export, but also in gross domestic product composition. This high economic dependency on natural resources on one hand has recently generated a material wealth of Middle Eastern countries...
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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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Rigid polyurethane foams modified with selected flame retardants
PublikacjaThe flame retardants: expandable graphite, triethylphosphatehas been used in rigid polyurethane foams (PUFs). The influence of fillers amounts on processing parameters, physical-mechanical properties (compression strength, density, water absorption, brittleness)and thermal properties (thermal stability) of such foams has been analyzed.The gel, cram and rise time for PUFs modified with flame retardant has been observed during synthesis...
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A case study of robust sliding mode control applied to inverted pendulum on a cart
PublikacjaA control problem of an inverted pendulum on a cart has been addressed in this paper. In particular, a synthesis of alternative sliding mode control for stabilisation of an inverted pendulum at an upper equilibrium point has been investigated. Hence, the feasibility of implementing the developed control system, taking into account primarily the friction of the cart against the gantry and the limited length of the gantry, in a real...
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A robust sliding mode observer for non-linear uncertain biochemical systems
PublikacjaA problem of state estimation for a certain class of non-linear uncertain systems has been addressed in this paper. In particular, a sliding mode observer has been derived to produce robust and stable estimates of the state variables. The stability and robustness of the proposed sliding mode observer have been investigated under parametric and unstructured uncertainty in the system dynamics. In order to ensure an unambiguous non-linear...
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Analysis of The Behavior of Foundations of Historical Buildings
PublikacjaThe article is devoted to the analysis of the behavior of the foundations of historic buildings. Some basic aspects of foundation engineering are discussed, with an emphasis placed on its development, applied techniques, and materials. Several different approaches and methods for the analysis of foundations of historical buildings are presented. A particular analysis has been focused on an example of a typical stone foundation...
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Apparent molar volumes, expansibilities, and isentropic compressibilities of selected electrolytes in methanol
PublikacjaDensities of solutions of sodium bromide, sodium perchlorate, sodium tetraphenylborate, and tetraphenylphosphonium bromide in methanol at the temperatures ranging from 283.15 to 313.15 K have been measured. Ultrasound velocities for the above systems at T = 298.15 K have been determined. From the obtained data, the partial molar volumes and the partial molar isentropic compressibilities for electrolytes in solution have been estimated....
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Big Data Processing by Volunteer Computing Supported by Intelligent Agents
PublikacjaIn this paper, volunteer computing systems have been proposed for big data processing. Moreover, intelligent agents have been developed to efficiency improvement of a grid middleware layer. In consequence, an intelligent volunteer grid has been equipped with agents that belong to five sets. The first one consists of some user tasks. Furthermore, two kinds of semi-intelligent tasks have been introduced to implement a middleware...
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An Improvement of Global Complex Roots and Poles Finding Algorithm for Propagation and Radiation Problems
PublikacjaAn improvement of the recently developed global roots finding algorithm has been proposed. The modification allows to shorten the computational time by reducing the number of function calls. Moreover, both versions of the algorithms (standard and modified) have been tested for numerically defined functions obtained from spectral domain approach and field matching method. The tests have been performed for three simple microwave...
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Task Assignments in Logistics by Adaptive Multi-Criterion Evolutionary Algorithm with Elitist Selection
PublikacjaAn evolutionary algorithm with elitist selection has been developed for finding Pareto-optimal task assignments in logistics. A multi-criterion optimization problem has been formulated for finding a set of Pareto- optimal solutions. Three criteria have been applied for evaluation of task assignment: the workload of a bottleneck machine, the cost of machines, and the numerical performance of system. The machine constraints have...
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Characterization of magnesium doped lanthanum orthoniobate synthesized by molten salt route
PublikacjaMolten salt synthesis method has been used to prepare the single phase magnesium doped lanthanum orthoniobate. The phase composition has been checked by X-ray diffraction method and the microstructure studies have been performed by scanning electron microscopy. The high temperature properties of the material have been investigated by thermogravimetry and electrochemical impedance spectroscopy. A dependence between sample total...
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Image Processing Techniques for Distributed Grid Applications
PublikacjaParallel approaches to 2D and 3D convolution processing of series of images have been presented. A distributed, practically oriented, 2D spatial convolution scheme has been elaborated and extended into the temporal domain. Complexity of the scheme has been determined and analysed with respect to coefficients in convolution kernels. Possibilities of parallelisation of the convolution operations have been analysed and the results...
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Effect of oxygenation time on signal of a sensor based on ionic liquids
PublikacjaThe paper presents an oxygen sensor based on ionic liquids and solid electrodes. The following ionic liquids have been employed: [BMIM][BF4], [HMIM][Cl], [BMIM][N(CN2)]. Minimum time of the sensor exposure to analyte, after which the signal (current intensity) was stable, has been evaluated. An impact of volumetric flow rate of analyte on the sensor exposure time and signal has been determined. A product of permeability coefficient...
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Metamaterial-Based Sub-Microwave Electromagnetic Field Energy Harvesting System
PublikacjaThis 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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Identification of Bodner-Partom model parameters for technical fabrics
PublikacjaThe thorough analysis of modeling technical fabrics behavior with the viscoplastic Bodner-Partom constitutive law is presented. The study has been focused on differences between the warp and weft direction of the material. To obtain the model’s parameters only the uniaxial tensile laboratory tests with three different, but constant strain rates are required. The parameters have been found for polyester fibers PVC coated fabrics:...
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EFFECTS OF DOPING ON STRUCTURE AND PHASE TRANSITION OF HIGH TEMPERATURE PROTON CONDUCTOR LaNb1-xMxO4-σ (M=As, Sb, V, Ta AND X=0,05 TO 0,3)
PublikacjaIn this work synthesis of lanthanum orthoniobate has been done. Doping by arsenic, antimony, vanadium or tantalum in 5% to 30% have been introduced. The relationship between doping type and percentage and structural properties of the material have been investigated.
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Multi-criterion, evolutionary and quantum decision making in complex systems
PublikacjaMulti-criterion, evolutionary and quantum decision making supported by the Adaptive Quantum-based Multi-criterion Evolutionary Algorithm (AQMEA) has been considered for distributed complex systems. AQMEA had been developed to the task assignment problem, and then it has been applied to underwater vehicle planning as another benchmark three-criterion optimization problem. For evaluation of a vehicle trajectory three criteria have...
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Analysis of the usage possibility of the electromagnetic curtain
PublikacjaIn the article the definition of IED has been presented as well as its classification and countering methods. The concept of AEGIS device for neutralization of RCIED has been presented. The usage possibility of AEGIS device in civilian environments has been analy sed
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Detection of damages in a rivetted plate
PublikacjaThe paper presents the results of damage detection in a riveted aluminium plate. The detection method has been based on Lamb wave propagation. The plate has been analysed numerically and experimentally. Numerical calculations have been carried out by the use of the time-domain spectral finite element method, while for the experimental analysis laser scanning Doppler vibrometry (LSDV) has been utilised. The panel has been excited...
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Parameters’ Identification of Perzyna and Chaboche Viscoplastic Models for Aluminum Alloy at Temperature of 120◦C
PublikacjaThe main purpose of this paper is the parameters identification of the Perzyna and the Chaboche models for the aluminum alloy at elevated temperature. The additional purpose is comparison of the results for these viscoplastic models. The results have been verified by the numerical simulation of the laboratory tests. The material parameters have been calculated on the basis of the uniaxial tension test. The determination of the...
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Study on the Influence of an Axial Distance Between Rotors on a Performance of a Small Counter-Rotating Wind Turbine
PublikacjaIn this paper, results of the investigation on the performance of a small counter-rotating wind turbinehas been presented. Computational Fluid Dynamics methodshave been used forwind turbine simulations. Rotors representation were introduced into computational domain by means of Actuator Line Model. Influence of an axial distance of CRWTrotorshas been investigated. In all studied configurations rotors were counter-rotating...
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Mechanical analysis of eccentric defected bilayer graphene sheets considering the van der Waals force
PublikacjaIn this article, we have tried to simulate nonlinear bending analysis of a double-layered graphene sheet which contains a geometrical imperfection based on an eccentric hole. The first-order shear deformation theory is considered to obtain the governing equations. Also, the nonlinear von Kármán strain field has been assumed in order to obtain large deformations. Whereas the double-layered graphene sheet has been considered, the...
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Antimicrobial Activity of Honey
PublikacjaHoney has had a valued place in traditional medicine for centuries. It was used to overcome liver, cardiovascular and gastrointestinal problems and for treatment of some types of infectious disease. Particularly, good results were achieved in the case of application of this product for therapy of infected, difficult to heal wounds. The high health-promoting properties of honey have been recently confirmed in many research investigations....
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Mixed integer nonlinear optimization of biological processes in wastewater sequencing batch reactor
PublikacjaWastewater treatment plays a key role for humanity. The waste entering lakes, rivers, and seas deteriorates daily quality of life. Therefore, it is very important to improve the efficiency of wastewater treatment. From a control point of view, a biological wastewater treatment plant is a complex, non-linear, multidimensional, hybrid control system. The paper presents the design of the optimizing hierarchical control system applied...
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Robust asymptotic super twisting sliding mode observer for non-linear uncertain biochemical systems
PublikacjaThe problem of state estimation (reconstruction of the state vector) for a given class of biochemical systems under uncertain system dynamics has been addressed in this paper. In detail, the bioreactor at a water resource recovery facility represents the considered biochemical systems. The biochemical processes taking place in the bioreactor have been modelled using an activated sludge model. Based on this model, an appropriate...
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An automatic selection of optimal recurrent neural network architecture for processes dynamics modelling purposes
PublikacjaA problem related to the development of algorithms designed to find the structure of artificial neural network used for behavioural (black-box) modelling of selected dynamic processes has been addressed in this paper. The research has included four original proposals of algorithms dedicated to neural network architecture search. Algorithms have been based on well-known optimisation techniques such as evolutionary algorithms and...
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Application of wet powder spraying for anode supported solid oxide fuel cell with a perowskite SrTi0.98Nb0.02O3-d anode
PublikacjaAnode-supported solid oxide fuel cell with SrTi0.98Nb0.02O3–d anode, yttria-stabilized zirconia electrolyte and La(Ni0.6Fe0.4) O3d cathode has been successfully fabricated and evaluated. Process of anode support fabrication has been presented. Wet powder spraying and high temperature sintering method have been studied and applied to deposit the thin electrolyte layer.In order to improve catalytic properties of the anode, it has...
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rigid polyurethane foams modified with selected nanofillers
PublikacjaThe nanofillers: natural montmoryllonite (MMT) - Bentonite, natural MMT modified with a quaternary ammonium salt - Cloisite30B, has been used in rigid polyurethane foams (PUFs). The influence of fillers amounts on processing parameters, physical-mechanical properties (density, water absorption, brittleness and compression strength) and thermal properties (thermal stability, fire behaviours) of such foams has been analysed. The...
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A selection of PID type controller settings via LQR approach for two-wheeled balancing robot
PublikacjaThe problem of PID type controller tuning has been addressed in this paper. In particular, a method of selection of PD settings based on the solution of linear–quadratic optimisation problem using the energy criterion has been investigated. Thus, the possibility of transforming optimal settings of the linear–quadratic regulator into the settings of the controller in the classical control system has been given. The presented methodology...
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Assessment of diversity and composition of bacterial community in Sludge Treatment Reed Bed systems
PublikacjaDue to their low emission of odours and lack of the need to apply additional chemical agents, sludge treatment reed beds (STRBs) constitute an economically feasible and eco-friendly approach to sewage sludge management. Correctly designed and operated STRBs ensure effective reduction of the dry matter content coupled with the mineralisation of organic compounds. Successful operation of STRBs relies on complex interactions between...
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Performance of data transmission in UMTS with turbo code about decreased number of states
PublikacjaIn the paper a structure of turbo encoder and decoder about decreased number of states has been described. The simulation results of transmission performance based on turbo coding without the reduction of the number of iterations for the uplink and downlink of WCDMA/FDD interface have been presented. The SOVA algorithm for turbo decoding has been used. The investigations have been carried out for Outdoor to Indoor & Pedestrian...
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1D portable optical coherence tomography system
Publikacja—Imaging methods are an expanding branch of technology, which involves data acquisition and analysis of images for research and diagnostics. This paper has been devoted to the description of the optical design for a one-dimensional, portable optical coherence tomography (OCT) system. The Mach-Zehnder interferometer has been designed in the presented study. The description of the construction and applied hardware solutions have...
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From structure to luminescence investigation of oxyfluoride transparent glasses and glass-ceramics doped with Eu3+/Dy3+ ions
PublikacjaGlasses and glass-ceramics with nominal composition 73 TeO2– 4BaO– 3Bi2O3–18SrF2-2RE2O3 (where RE = Eu, Dy) have been synthesized by conventional melt-quenching technique and subsequent heat treatment at 370 °C for 24 h in air atmosphere. Various Eu3+ to Dy3+ molar ratio have been applied to investigate luminescence properties in both glass and glass-ceramic matrices. Especially, white light emission through simultaneous excitation...
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Effect of manufacturing errors of the pad sliding surface on the performance of the hydrodynamic thrust bearing
PublikacjaIn the present study, investigation of the effect of manufacturing errors on the performance of large tilting pad thrust bearings has been performed, following a CFD-based Thermohydrodynamic analysis of a single pad. A 3D model has been generated, including the pad, the lubricant film and the corresponding part of the collar. The pad has been assumed to be deformed about the pivot point, due to thrust loading. Manufacturing errors...
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Impedance of cation-coupled electron transfer reaction: Theoretical description of one pathway process
PublikacjaIt has been assumed that cation electron coupled charge transfer can be conducted in accordance with two mutually coupled reactions. Using a differential method an expression was introduced which describes the impedance of a cation electron coupled transfer reaction. Also, an electrical equivalent circuit has been defined. The total faradaic impedance is the sum of electron transfer impedance and cation transfer impedance. Issues...