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Numerically efficient algorithm for compact microwave device optimization with flexible sensitivity updating scheme
PublikacjaAn efficient trust-region algorithm with flexible sensitivity updating management scheme for electromagnetic (EM)-driven design optimization of compact microwave components is proposed. During the optimization process, updating of selected columns of the circuit response Jacobian is performed using a rank-one Broyden formula (BF) replacing finite differentiation (FD). The FD update is omitted for directions sufficiently well aligned...
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Is Artificial Intelligence Ready to Assess an Enterprise’s Financial Security?
PublikacjaThis study contributes to the literature on financial security by highlighting the relevance of the perceptions and resulting professional judgment of stakeholders. Assessing a company’s financial security using only economic indicators—as suggested in the existing literature—would be inaccurate when undertaking a comprehensive study of financial security. Specifically, indices and indicators based on financial or managerial reporting...
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Ship domain applied to determining distances for collision avoidance manoeuvres in give-way situations
PublikacjaShip domain is often used in marine navigation and marine traffic engineering as a safety condition. The basic idea behind those applications is that an encounter of two or more ships can be considered safe if neither of ship domains is intruded by other ships. Research utilising this approach has been documented in numerous works, including publications on optimising collision avoidance manoeuvres performed to fulfil domain-based...
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ANALYSIS OF ROLLING RESISTANCE OF TIRES WITH RUN FLAT INSERT APPLYING DRUM METHOD AND RADIAL CHARACTERISTIC
PublikacjaThis paper presents analysis of rolling resistance of tires with RUN FLAT insert applying drum method and radial characteristic. The conducted studies indicated changes in operational properties of wheel, occurring as a result of inflation pressure drop in the wheel. As regards radial elasticity, such changes result in significant drop of radial rigidity and increase of static deflection and increase of tire rolling resistance....
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Connection matrix theory for discrete dynamical systems
PublikacjaIn [C] and [F1] the connection matrix theory for Morse decomposition is developedin the case of continuous dynamical systems. Our purpose is to study the case of discrete timedynamical systems.
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INNOVATIVE THERMODYNAMICAL CYCLES BASED ON ENHANCEMENT MASS, MOMENTUM, ENTROPY AND ELECTRICITY TRANSPORT DUE TO SLIP, MOBILITY, TRANSPIRATION, ENTROPY AND ELECTRIC JUMPS AS WELL AS OTHER NANO-FLOWS PHENOMENA
PublikacjaIn our work, a further development of the authors model of thermo-chemical flow of fuel, air, oxygen, steam water, species, ionic and electron currents within nano channels and nano-structures of novel devices is presented. Different transport enhancement models are taken into account -among them the most important are: the velocity slip connected with complex external friction, the Darcy mobility and the Reynolds transpiration....
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Manufacture and research of TPS/PE biocomposites properties
PublikacjaIn this paper the process of native starch preparing for modification by extrusion and manufacture of biocomposites is presented. The first aim of this study was to determine the mixing and granulating condition of native starch to obtain granulated native starch. For mixing and granulation of native starch Intensive Mixer manufactured by Maschinenfabrik Gustav Eirich was used. Mixing and granulation in a single process is a new...
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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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Multi-criteria Robot Selection Problem for an Automated Single-Sided Lapping System
PublikacjaFlat lapping is a crucial process in a number of precision manufacturing technologies. Its aim is to achieve extremely high flatness of the workpiece. Single-sided lapping machines have usually standard kinematic systems and are used in conjunction with conditioning rings, which are set properly be-tween the center and the periphery of the lapping plate. In this paper, instead of conventional single-side lapping machine, an automated...
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Controlled grafting of vinylic monomers on polyolefins: a robust mathematical modeling approach
PublikacjaExperimental and mathematical modeling analyses were used for controlling melt free-radical grafting of vinylic monomers on polyolefins and, thereby, reducing the disturbance of undesired cross-linking of polyolefins. Response surface, desirability function, and artificial intelligence methodologies were blended to modeling/optimization of grafting reaction in terms of vinylic monomer content, peroxide initiator concentration,...
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Proposal of New Tracer Concentration Model in Lung PCT Study Comparison with Commonly Used Gamma-variate Model
PublikacjaPerfusion computed tomography (pCT) is one of the methods that enable non-invasive imaging of the hemodynamics of organs and tissues. On the basis of pCT measurements, perfusion parameters such as blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface (PS) are calculated and then used for quantitative evaluation of the tissue condition. To calculate perfusion parameters it is necessary to approximate...
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Numerical Analysis of Recharge Rates and Contaminant Travel Time in Layered Unsaturated Soils
PublikacjaThis study focused on the estimation of groundwater recharge rates and travel time of conservative contaminants between ground surface and aquifer. Numerical simulations of transient water flow and solute transport were performed using the SWAP computer program for 10 layered soil profiles, composed of materials ranging from gravel to clay. In particular, sensitivity of the results to the thickness and position of weakly permeable...
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Diagnostic Model of Crankshaft Seals
PublikacjaT he paper presents a research stand being a diagnostic model of radial lip seals used, among others, on crankshafts of piston combustion engines in order to identify the correctness of their operation. The possibility of determining the technical condition of lip seals on the basis of the proposed coefficient of correctness of operation has been described. T he basic features of seals influencing their correctness of...
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Study of Slip Effects in Reverse Roll Coating Process Using Non-Isothermal Couple Stress Fluid
PublikacjaThe non-isothermal couple stress fluid inside a reverse roll coating geometry is considered. The slip condition is considered at the surfaces of the rolls. To develop the flow equations, the mathematical modelling is performed using conservation of momentum, mass, and energy. The LAT (lubrication approximation theory) is employed to simplify the equations. The closed form solution for velocity, temperature, and pressure gradient...
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Analytical chemistry in technical approaches: immobilization of biosorbent waste containing heavy metals in cemented materials
PublikacjaAn ecologically safe and economically justified method of stabilization of the used biosorbents was developed. Sorbent contaminated with heavy metals has been successfully solidified/stabilized using a hydraulic binder. The test results indicated that up to 1% of the biosorbent residue used could be added without compromising the compressive strength of the mortar. The compressive strength of the modified mortars did not change...
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Self-Adaptive Mesh Generator for Global Complex Roots and Poles Finding Algorithm
PublikacjaIn any global method of searching for roots and poles, increasing the number of samples increases the chances of finding them precisely in a given area. However, the global complex roots and poles finding algorithm (GRPF) (as one of the few) has direct control over the accuracy of the results. In addition, this algorithm has a simple condition for finding all roots and poles in a given area: it only requires a sufficiently dense...
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High-Temperature Tensile Behaviour of GTAW Joints of P92 Steel and Alloy 617 for Two Different Fillers
PublikacjaThis study explores the high-temperature (HT) tensile rupture characteristics of a dissimilar gas-tungsten-arc-welded (GTAW) joint between P92 steel and Alloy 617, fabricated using ER62SB9 and ERNiCrCoMo-1 fillers. The high-temperature tensile tests were performed at elevated temperatures of 550 ◦C and 650 ◦C. An optical microscope (OM) and a field emission scanning electron microscope (FESEM) were utilized to characterize the...
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Fault detection in the marine engine using a support vector data description method
PublikacjaFast detection and correct diagnosis of any engine condition changes are essential elements of safety andenvironmental protection. Many diagnostic algorithms significantly improve the detection of malfunctions.Studies on diagnostic methods are rarely reported and even less implemented in the marine engine industry.To fill this gap, this paper presents the Support Vector Data Description (SVDD) method as applied to thefault detection...
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Seismic probabilistic assessment of steel and reinforced concrete structures including earthquake-induced pounding
PublikacjaRecent earthquakes demonstrate that prioritizing the retrofitting of buildings should be of the utmost importance for enhancing the seismic resilience and structural integrity of urban structures. To have a realistic results of the pounding effects in modeling process of retrofitting buildings, the present research provides seismic Probability Factors (PFs), which can be used for estimating collision effects without engaging in...
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Effective Gap Size Index for Determination of Optimum Separation Distance Preventing Pounding between Buildings during Earthquakes
PublikacjaSeismic excitations may lead to collisions between adjacent civil engineering structures causing major damage. In this paper, an effective equation for calculating the gap size index is proposed so as to provide the optimum separation distance preventing structural pounding during different earthquakes. Evaluation of the best prediction of the required separation distance between two adjacent buildings was carried out by using...
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Tin Oxide Encapsulated into Pyrolyzed Chitosan as a Negative Electrode for Lithium Ion Batteries
PublikacjaTin oxide is one of the most promising electrode materials as a negative electrode for lithium-ion batteries due to its higher theoretical specific capacity than graphite. However, it suffers lack of stability due to volume changes and low electrical conductivity while cycling. To overcome these issues, a new composite consisting of SnO2 and carbonaceous matrix was fabricated. Naturally abundant and renewable chitosan was chosen...
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Nuclear Magnetic Resonance Metabolomics Reveals Qualitative and Quantitative Differences in the Composition of Human Breast Milk and Milk Formulas
PublikacjaCommercial formula milk (FM) constitutes the best alternative to fulfill the nutritional requirements of infants when breastfeeding is precluded. Here, we present the comparative study of polar metabolite composition of human breast milk (HBM) and seven different brands of FM by nuclear magnetic resonance spectroscopy. The results of the multivariate data analysis exposed qualitative and quantitative differences between HBM and...
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Hybrid Finite Element Method Development for Offshore Structures’ Calculation with the Implementation of Industry Standards
PublikacjaIn the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulation and evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modeling and solution rely on finite element methods and cover the simulation of the structure’s properties along with the influence of the marine environment – sea currents, wave and wind loading,...
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Improving Traffic Light Recognition Methods using Shifting Time-Windows
PublikacjaWe propose a novel method of improving algorithms recognizing traffic lights in video sequences. Our focus is on algorithms for applications which notify the driver of a light in sight. Many existing methods process images in the recording separately. Our method bases on the observation that real-life videos depict underlying continuous processes. We named our method FSA (Frame Sequence Analyzed). It is applicable for any underlying...
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Experimental research of the effect of face milling strategy on the flatness deviations
PublikacjaIn this paper the dependencies between face milling strategy of EN AW6082-T6 aluminum alloy samples, with difference thicknesses (6, 8, and 12 mm) and two cold rolling directions, and flatness deviations were presented. Three strategies of milling included different proportions of material removed from both sides of the plates. This approach allowed to control the proportions of residual surface stresses on both sides of the specimens,...
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Processing of Ce0.8Gd0.2O2-δ barrier layers for solid oxide cells: The effect of preparation method and thickness on the interdiffusion and electrochemical performance
PublikacjaCe0.8Gd0.2O1.9 (CGO) barrier layers are required to mitigate the chemical reactions between Sr-containing oxygen electrode materials and Zr-based oxygen ion conductors in high-temperature solid oxide cells. Barrier layers produced by different methods were studied in this work. As a reference, a cell with no barrier layer was measured. The application of the powder-processed barrier layers, considerably increases the performance....
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Ranking Speech Features for Their Usage in Singing Emotion Classification
PublikacjaThis paper aims to retrieve speech descriptors that may be useful for the classification of emotions in singing. For this purpose, Mel Frequency Cepstral Coefficients (MFCC) and selected Low-Level MPEG 7 descriptors were calculated based on the RAVDESS dataset. The database contains recordings of emotional speech and singing of professional actors presenting six different emotions. Employing the algorithm of Feature Selection based...
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Bio-Based Polyurethane Composites and Hybrid Composites Containing a New Type of Bio-Polyol and Addition of Natural and Synthetic Fibers
PublikacjaThis article describes how new bio-based polyol during the liquefaction process can be obtained. Selected polyol was tested in the production of polyurethane resins. Moreover, this research describes the process of manufacturing polyurethane materials and the impact of two different types of fibers—synthetic and natural (glass and sisal fibers)—on the properties of composites. The best properties were achieved at a reaction temperature...
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Multi-objective design optimization of antennas for reflection, size, and gain variability using kriging surrogates and generalized domain segmentation
PublikacjaCost-efficient multi-objective design optimization of antennas is presented. The framework exploits auxiliary data-driven surrogates, a multi-objective evolutionary algorithm for initial Pareto front identification, response correction techniques for design refinement, as well as generalized domain segmentation. The purpose of this last mechanism is to reduce the volume of the design space region that needs to be sampled in order...
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Application of Structural Control Systems for the Cables of Cable-Stayed Bridges: State-of-the-Art and State-of-the-Practice
PublikacjaStay cables are one of the key elements of cable-stayed bridges and are characterized by lightweight, low inherent damping, and high flexibility. They are continuously subjected to small-to large-amplitude vibrations due to various types of dynamic loads that may, in the long term, cause fatigue and fracture problems for the cable system, and may eventually compromise the safety of cable-stayed bridges. Thus, several countermeasures...
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Optimized Computational Intelligence Model for Estimating the Flexural Behavior of Composite Shear Walls
PublikacjaThis article presents a novel approach to estimate the flexural capacity of reinforced concrete-filled composite plate shear walls using an optimized computational intelligence model. The proposed model was developed and validated based on 47 laboratory data points and the Transit Search (TS) optimization algorithm. Using 80% of the experimental dataset, the optimized model was selected by determining the unknown coefficients of...
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Review of the Usefulness of Various Rotational Seismometers with Laboratory Results of Fibre-Optic Ones Tested for Engineering Applications
PublikacjaStarting with descriptions of rotational seismology, areas of interest and historical field measurements, the fundamental requirements for rotational seismometers for seismological and engineering application are formulated. On the above basis, a review of all existing rotational seismometers is presented with a description of the principles of their operation as well as possibilities to fulfill formulated requirements. This review...
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Design and distribution of air nozzles in the biomass boiler assembly
PublikacjaDue to energy crisis as well as increasing pollution of the environment, renewable energy sources usage increases all over the world. These facts encouraged authors to start research over developing a uniform biomass boiler calculation model. This paper presents a design of biomass boiler assembly created for ORC (Organic Rankine Cycle) unit since these systems could achieve strong position in energy industry....
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The structure of knowledge resources supporting a model of IT technologies architecture = Struktury zasobów wiedzy wspierających model architektury technologii IT
PublikacjaThis paper introduces an abstract model for tools used in the software engineering process. The main goal of the research is to develop a universal model which allows a description of tools used in the process. The model supports a decision making process and gives an option to choose the best tooling for the situation. The model considers many factors including, but not exclusive to, the company structure, project environment...
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The evolving structure of Polish exports (1994-2010) - diversification of products and trade partners.
PublikacjaThis paper presents empirical evidence on the diversification process concerning Polish exports (1994–2010), compared to European and global samples of countries. It analyzes both the commodity structure of Polish trade and the geographical diversification of Poland’s trading partners. The analysis draws on highly disaggregated data on exports (HS 6 digit) and combines descriptive analysis with non-parametric, semi-parametric and...
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Softly Switched Robustly Feasible Model Predictive Control for Nonlinear Network Systems
PublikacjaIt is common that an efficient constrained plant operation under full range of disturbance inputs require meeting different sets of control objectives. This calls for application of model predictive controllers each of them being best fit into specific operating conditions. It further requires that not only designing robustly feasible model predictive controllers is needed to satisfy the real plant state/output constraints, but...
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Multiple sound sources localization in free field using acoustic vector sensor
PublikacjaMethod and preliminary results of multiple sound sources localization in free field using the acoustic vector sensor were presented in this study. Direction of arrival (DOA) for considered source was determined based on sound intensity method supported by Fourier analysis. Obtained spectrum components for considered signal allowed to determine the DOA value for the particular frequency independently. The accuracy of the developed...
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Pressure-induced phase transitions in LnTe (Ln=La, Gd, Ho, Yb) and AmTe
PublikacjaThe structural behaviour under compression of different lanthanide (La, Gd, Ho, Yb) and actinide (Am) monochalcogenides is studied by means of in situ high-pressure x-ray diffraction. All the investigated compounds crystallize at ambient conditions within a cubic (B1) NaCl-type structure but show different behaviours at high pressures. LaTe and AmTe undergo B1 to B2 (CsCl-type structure) phase transitions, starting at 9 GPa and...
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Quality measure of VoIP services in carrier grade systems
PublikacjaThis paper describes passive measurement method of VoIP services quality in carrier grade systems, engaging slight system resources. Measurement is based on analyzing quality information in sender and receiver reports in RTCP packets sent by the end points of RTP session. Data is analyzed and stored by Session Boarder Controllers SBC. Objective evaluation of VoIP calls is based on quality information of IP connection and voice...
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Comparison of High Performance Liquid Chromatography Methods with Different Detectors for Determination of Steroid Hormones in Aqueous Matrices
PublikacjaThis paper presents the development and comparison of procedures for the qualitative and quantitative determination of five estrogenic compounds (17-a-ethynylestradiol, estrone, estradiol, estriol, and progesterone) in drinking water and wastewater samples. Five extraction columns and two disks were tested for their efficiency. The C18 columns were superior on the basis of cost for solid phase extraction of drinking water or sewage....
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Low-Cost EM-Simulation-Driven Multi-Objective Optimization of Antennas
PublikacjaA surrogate-based method for efficient multi-objective antenna optimization is presented. Our technique exploits response surface approximation (RSA) model constructed from sampled low-fidelity antenna model (here, obtained through coarse-discretization EM simulation). The RSA model enables fast determination of the best available trade-offs between conflicting design goals. A low-cost RSA model construction is possible through...
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A Regular Expression Matching Application with Configurable Data Intensity for Testing Heterogeneous HPC Systems
PublikacjaModern High Performance Computing (HPC) systems are becoming increasingly heterogeneous in terms of utilized hardware, as well as software solutions. The problems, that we wish to efficiently solve using those systems have different complexity, not only considering magnitude, but also the type of complexity: computation, data or communication intensity. Developing new mechanisms for dealing with those complexities or choosing an...
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Relation-based Wikipedia Search System for Factoid Questions Answering
PublikacjaIn this paper we propose an alternative keyword search mechanism for Wikipedia, designed as a prototype solution towards factoid questions answering. The method considers relations between articles for finding the best matching article. Unlike the standard Wikipedia search engine and also Google engine, which search the articles content independently, requiring the entire query to be satisfied by a single article, the proposed...
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A new quaternion-based encryption method for DICOM images
PublikacjaIn this paper, a new quaternion-based lossless encryption technique for digital image and communication on medicine (DICOM) images is proposed. We have scrutinized and slightly modified the concept of the DICOM network to point out the best location for the proposed encryption scheme, which significantly improves speed of DICOM images encryption in comparison with those originally embedded into DICOM advanced encryption standard...
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Rapid multi-objective antenna design using point-by-point Pareto set identification and local surrogate models
PublikacjaAntenna design is inherently a multicriterial problem.Determination of the best possible tradeoffs between conflicting objectives (a so-called Pareto front), such as reflection response, gain, and antenna size, is indispensable from the designer’s point of view, yet challenging when high-fidelity electromagnetic (EM) simulations are utilized for performance evaluation. Here, a novel and computationally...
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Pressure drop of HFE7000 and HFE7100 during flow condensation in minichannels
PublikacjaAttention is focused on the issues of flow resistance and pressure drop of perspective refrigeration fluids during condensation in the two-phase flow in minichannels. The case of the flow through a cylindrical single channel of 2.3 mm inner diameter was carefully analyzed. Pressure drop tests have been performed in diabatic flow conditions. The effect of heat flux, mass flux, vapour quality and saturation temperature on the two-phase...
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Eqiuitable coloring of corona products of cubic graphs is harder than ordinary coloring
PublikacjaA graph is equitably k-colorable if its vertices can be partitioned into k independent sets in such a way that the number of vertices in any two sets differ by at most one. The smallest k for which such a coloring exists is known as the equitable chromatic number of G. In this paper the problem of determinig the equitable coloring number for coronas of cubic graphs is studied. Although the problem of ordinary coloring of coronas...
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Testbed analysis of video and VoIP transsmission performance in IEEE 802.11 b/g/n networks
PublikacjaThe aim of the work is to analyze capabilities and limitations of different implementations of IEEE 802.11 technologies (IEEE 802.11 b/g/n), utilized for both video streaming and VoIP calls directed to mobile devices. Our preliminary research showed that results obtained with currently popular simulation tools can be drastically different than these possible in real-world environment, so, in order to correctly evaluate performance...
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The Method of Multi-criteria Analysis to Support the Decision on Load or Micro-generation Connection to a Low- or Medium-voltage Power Grid
PublikacjaThis paper presents a method that supports the decision in terms on selecting the best option of a load connection to a low- or medium-voltage power distribution grid, and of a micro-generation source connection to a low-voltage grid. The method is based on the search for the option with the lowest aggregate assessment measure, which is the weighted average of partial assessment measures determined for each of eight considered...
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Rheological characteristics of oligomeric semiproducts gained via chemical degradation of polyurethane foam using crude glycerin in the presence of different catalysts
PublikacjaPolyurethane (PU) recycling is a topic of growing interest due to the increasing amount of polyurethane waste. The main purpose of polyurethane chemical recycling is to recover the starting polyol. In this study, a method of polyurethane thermochemical recycling, glycerolysis by means of crude glycerin, is proposed. This work presents a comparative study of commercial catalysts used in order to accelerate the decomposition process,...