Filtry
wszystkich: 1872
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: acoustic biomass estimation
-
Acoustic journal bearing - A search for adequate configuration
PublikacjaClassical non-contact bearings are already used in a number of specialist applications but there are somespecialist areas where they cannot be used for variety of reasons and acoustic sliding bearings could be an alternative. The paper presents the quest for a configuration of an acoustic journal bearing and shows that the overall shape of the bearing and its geometry are of a vital importance for the load capacity oft he bearing....
-
Machine learning for the management of biochar yield and properties of biomass sources for sustainable energy
PublikacjaBiochar is emerging as a potential solution for biomass conversion to meet the ever increasing demand for sustainable energy. Efficient management systems are needed in order to exploit fully the potential of biochar. Modern machine learning (ML) techniques, and in particular ensemble approaches and explainable AI methods, are valuable for forecasting the properties and efficiency of biochar properly. Machine-learning-based forecasts,...
-
Processing of Biomass Prior to Hydrogen Fermentation and Post-Fermentative Broth Management
PublikacjaUsing bioconversion and simultaneous value-added product generation requires purifica- tion of the gaseous and the liquid streams before, during, and after the bioconversion process. The effect of diversified process parameters on the efficiency of biohydrogen generation via biological pro- cesses is a broad object of research. Biomass-based raw materials are often applied in investigations regarding biohydrogen generation using...
-
Signatures and acoustic images of objects moving in water
PublikacjaObservation of underwater space is part of a generaltrend, which primary purpose is to protect and increasesafety in the selected area. The basic aim of the paper ispresentation of designated acoustic characteristics typicalfor objects moving on the water surface and under water,which represent some knowledge about detection of theseobjects. Create a catalog of acoustic signature and not onlyacoustic, as well as acoustic images...
-
FTIR spectrum for biologically pre-treated lignocellulosic biomass
Dane BadawczeDataset contains FTIR spectrum data for lignocellulosic biomass obtained during the biological pretreatment period with the application of wild red, white and brown Rot Fungi.
-
Biomass of macrophytobentos in the Puck Bay in 2010-2018
Dane BadawczeThe database contains data on qualitative composition and biomass of macrophytobenthos (flower plants and macroalgae) in samples collected in the Puck Bay area (Gulf of Gdańsk, southern Baltic Sea) at 20 stations between 2010-2018. The database contains information on sampling sites (region, geographical coordinates, depth), sample characteristics (date,...
-
Identification of Unstable Reference Points and Estimation of Displacements Using Squared Msplit Estimation
PublikacjaThe article presents a new version of the method for estimating parameters in a split functional model, which enables the determination of displacements of geodetic network points with constrained datum. The main aim of the study is to present theoretical foundations of Msplit CD estimation and its basic properties and possible applications. Particular attention was paid to the efficacy of the method in the context of geodetic...
-
Novel Biomass-Based Polymers: Synthesis, Characterization, and Application
PublikacjaA wide range of polymers were prepared from biomass-derivatives, using different polymerization mechanisms. Well-defined, fully hydroxy-functional polyesters based on aliphatic diols were synthesized, using either conventional metal-based catalysts or the organic superbase 1,5,7-triazabicyclododecene (TBD). Unsaturated polyesters were also made, offering additional functionality to these biobased resins. Metal-catalyzed or enzymatic...
-
Production of hydrogen from biomass and its separation using membranetechnology
PublikacjaHydrogen is an important raw material for chemical industry and feasible renewable energy carrier that could replace fossil fuels. However, the specie seldom exists in a form of pure H2. Therefore, to obtain hydrogen in volumes suitable to be used as a raw material it is necesary to decompose hydrogen-rich compounds. The carbohydrate-rich biomass can be an important source of hydrogen by applying the process of dark fermentation....
-
Acoustic heating produced in resonators filled by a newtonian fluid
PublikacjaAcoustic heating in resonators is studied. The governing equation of acoustic heating is derived by means of the special linear combination of conservation equations in differential form, allowing the reduction of all acoustic terms in the linear part of the final equation, but preserving terms belonging to the thermal mode responsible for heating. This equation is instantaneous and includes nonlinear acoustic terms that form a...
-
The Examination of the Upper Layers of the Seabed by the Means of the Acoustic Methods
PublikacjaPropagation of acoustic waves in the sea, in particular in shallow sea, depends on several factors. The basic of them are source power and frequency of acoustic waves, spatial distribution inhomogeneous medium in which acoustic wave propagates, and distributions of speed of sound and density of seawater. The coastal conditions, which limit water medium from above (free surface of the sea) and from bottom (the seabed), are no less...
-
Theoretical Model of Acoustic Wave Propagation in Shallow Water
PublikacjaThe work is devoted to the propagation of low frequency waves in a shallow sea. As a source of acoustic waves, underwater disturbances generated by ships were adopted. A specific feature of the propagation of acoustic waves in shallow water is the proximity of boundaries of the limiting media characterised by different impedance properties, which affects the acoustic field coming from a source situated in the water layer “ deformed”...
-
Measurements of transmission properties of Acoustic Communication Channels
PublikacjaTough transmission properties of shallow water acoustic channels (SWAC) highly limit the use of underwater acoustic communication (UAC) systems. An adaptive matching of modulation and signaling schemes to instantaneous channel conditions is needed for reliabledata communications. This creates, however, unique challenges for designers when compared to radio transmission systems. When communication system elements are in move, the...
-
Acoustic heating produced in the thermoviscous flow of a Bingham plastic
PublikacjaThis study is devoted to the instantaneous acoustic heating of a Bingham plastic. The model of the Bingham plastic's viscous stress tensor includes the yield stress along with the shear viscosity, which differentiates a Bingham plastic from a viscous Newtonian fluid. A special linear combination of the conservation equations in differential form makes it possible to reduce all acoustic terms in the linear part of of the final equation...
-
Acoustic heating produced in the thermoviscous flow of a bingham plastic
PublikacjaThis study is devoted to the instantaneous acoustic heating of a Bingham plastic. The model of the Bingham plastic's viscous stress tensor includes the yield stress along with the shear viscosity, which differentiates a Bingham plastic from a viscous Newtonian fluid. A special linear combination of the conservation equations in differential form makes it possible to reduce all acoustic terms in the linear part of of the final equation...
-
Conversion of Biomass and Municipal Wastes into Syngas and Hydrogen using Highly Preheated Agent (HTAG)
PublikacjaGasification is considered to be one of the most promising energy recovery technologies for the widespread utilization of biomass and wastes. During this process raw feedstock is converted into a combustible gas, which can then be burnt to produce thermal energy, or to run engines for mechanical or electrical power. The studies of biomass gasification demonstrate it as a friendly alternative to fossil fuels as one of renewable...
-
Liquefaction of macroalgae Enteromorpha biomass for the preparation of biopolyols by using crude glycerol
PublikacjaThis article describes the liquefaction process of macroalgae Enteromorpha with the use of crude glycerol as a solvent and a reagent, aimed at obtaining of new bio-polyols, which are characterized with respect to their chemical structure, physical and thermal properties. Six different biopolyols were prepared. In order to optimize the liquefaction of algal biomass for the best bio-polyol properties, two catalysts (sulfuric or orthophosphoric...
-
Active Suppression of Nonstationary Narrowband Acoustic Disturbances
PublikacjaIn this chapter, a new approach to active narrowband noise control is presented. Narrowband acoustic noise may be generated, among others, by rotating parts of electro-mechanical devices, such as motors, turbines, compressors, or fans. Active noise control involves the generation of “antinoise”, i.e., the generation of a sound that has the same amplitude, but the opposite phase, as the unwanted noise, which causes them to interfere...
-
Key issues in modeling and optimization of lignocellulosic biomass fermentative conversion to gaseous biofuels
PublikacjaThe industrial-scale production of lignocellulosic-based biofuels from biomass is expected to benefit society and the environment. The main pathways of residues processing include advanced hydrolysis and fermentation, pyrolysis, gasification, chemical synthesis and biological processes. The products of such treatment are second generation biofuels. The degree of fermentation of organic substances depends primarily on their composition...
-
Lattice filter based autoregressive spectrum estimation with joint model order and estimation bandwidth adaptation
PublikacjaThe problem of parametric, autoregressive model based estimation of a time-varying spectral density function of a nonstationary process is considered. It is shown that estimation results can be considerably improved if identification of the autoregressive model is carried out using the two-sided doubly exponentially weighted lattice algorithm which combines results yielded by two one-sided lattice algorithms running forward in...
-
On Some Aspects of Fish Target Strength Estimation in Shallow Waters
PublikacjaThe theory of acoustic surveys for determining fish abundance are well established in fishery acoustics. The origins of the estimation are related to overcoming the problem of unknown position of target in the beam using statistical inversion. Although recently researchers use more sophisticated echosounders that provides more informative data allowing for direct solution it is known that the results are biased due to not ideally...
-
Generation of inhibitory compounds during pre-treatment of lignocellulosic biomass
Dane BadawczeDataset contains calibration curves and typical resultsa obtained during biomass pre-treatment. Data are converted from digital raw files to xlsx files
-
Acoustic Hysteresis in Flows with Different Kinds of Relaxation and Attenuation
PublikacjaGraphs in the thermodynamic plane acoustic pressure versus excess acoustic density representing acoustic hysteresis, are considered as indicators of relaxation processes, equilibrium parameters of a flow, and kinds of wave exciters. Some flows with deviation from adiabaticity are examined: the Newtonian flow of a thermocon- ducting gas, the flow of a gas with vibrational relaxation, the flow of liquid electrolyte with a chemical...
-
Efficiency of acoustic heating produced in the thermoviscous flow of a fluid with relaxation
PublikacjaInstantaneous acoustic heating of a fluid with thermodynamic relaxation is the subject of investigation. Among others, viscoelastic biological media described by the Maxwell model of the viscous stress tensor, belong to this type of fluid. The governing equation of acoustic heating is derived by means of the special linear combination of conservation equations in differential form, allowing the reduction of all acoustic terms in...
-
Estimation of Average Speed of Road Vehicles by Sound Intensity Analysis
PublikacjaConstant monitoring of road traffic is important part of modern smart city systems. The proposed method estimates average speed of road vehicles in the observation period, using a passive acoustic vector sensor. Speed estimation based on sound intensity analysis is a novel approach to the described problem. Sound intensity in two orthogonal axes is measured with a sensor placed alongside the road. Position of the apparent sound...
-
Recovery of Anammox Biomass at Short Hydraulic Retention Time in a MBR Reactor
PublikacjaThe anammox system has been consider as an economical option for treating high concentration of nitrogen and poor in biodegradable orgaednic carbon wastewaters. This process is attractive option compared with conventional nitrogen removal because it provides a significant saving in aeration and organic addition for denitrification. The anammox technology has been applied mostly for concentrated nitrogenous wastewater containing...
-
Prediction of the Mechanical Properties of P91 Steel by Means of Magneto-acoustic Emission and Acoustic Birefringence
PublikacjaThe paper describes an application of nondestructive volumetric magnetic and ultrasonic techniques for evaluation of the selected mechanical parameter variations of P91 steel having direct influence on its suitability for further use in critical components used in power plants. Two different types of deformation processes were carried out. First, a series of the P91 steel specimens was subjected to creep and second, one to plastic...
-
A system for acoustic field measurement employing cartesian robot
PublikacjaA system setup for measurements of acoustic field, together with the results of 3D visualisations of acoustic energy flow are presented in the paper. Spatial sampling of the field is performed by a Cartesian robot. Automatization of the measurement process is achieved with the use of a specialized control system. The method is based on measuring the sound pressure (scalar) and particle velocity (vector) quantities. The aim of the...
-
Limitations of WSSUS modeling of stationary underwater acoustic communication channel
PublikacjaPerformances of underwater acoustic communication (UAC) systems are strongly related to specific propagation conditions of the underwater channel. Due to their large variability, there is a need for adaptive matching of the UAC systems signaling to the transmission properties of the channel. This requires a knowledge of instantaneous channel characteristics, in terms of the specific parameters of stochastic models. The wide-sense...
-
Creating Acoustic Maps Employing Supercomputing Cluster
PublikacjaThe implemented online urban noise pollution monitoring system is presented with regard to its conceptual assumptions and technical realization. A concept of the noise source parameters dynamic assessment is introduced. The idea of noise modeling, based on noise emission characteristics and emission simulations, was developer and practically utilized in the system. Furthermore, the working system architecture and the data acquisition...
-
The Course and the Effects of Agricultural Biomass Pyrolysis in the Production of High-Calorific Biochar
PublikacjaThe thermal pyrolysis of agriculture biomass has been studied in a fixed-bed reactor, wherethe pyrolysis was conducted at a steady temperature of 800◦C. This work analyses the pyrolysisproducts of six agricultural wastes: pistachio husks, walnut husks, sunflower hulls, buckwheat husks,corncobs and coconut shells. The conducted research compared examples of large waste biomassstreams from different parts of the world as a potential...
-
Designing acoustic scattering elements using machine learning methods
PublikacjaIn the process of the design and correction of room acoustic properties, it is often necessary to select the appropriate type of acoustic treatment devices and make decisions regarding their size, geometry, and location of the devices inside the room under the treatment process. The goal of this doctoral dissertation is to develop and validate a mathematical model that allows predicting the effects of the application of the scattering...
-
Lattice filter based multivariate autoregressive spectral estimation with joint model order and estimation bandwidth adaptation
PublikacjaThe problem of parametric, autoregressive model based estimation of a time-varying spectral density function of a multivariate nonstationary process is considered. It is shown that estimation results can be considerably improved if identification of the autoregressive model is carried out using the two-sided doubly exponentially weighted lattice algorithm which combines results yielded by two one-sided lattice algorithms running...
-
Acoustic emission studies of the 7075 aluminium alloy pitting corrosion process
Dane BadawczeThe dataset contains the cyclic polarization studies and corresponding acoustic emission measurements, revealing the pitting corrosion process of the passive layer at the surface of the 7075 aluminum alloy in the borate buffer with different chloride ions concentrations, in the range between 0.05 and 25 mM.
-
Thermochemical Conversion of Biomass and Municipal Waste into Useful Energy Using Advanced HiTAG/HiTSG Technology
PublikacjaAn advanced thermal conversion system involving high-temperature gasification of biomass and municipal waste into biofuel, syngas or hydrogen-rich gas is presented in this paper. The decomposition of solid biomass and wastes by gasification is carried out experimentally with a modern and innovative regenerator and updraft continuous gasifier, among others. A ceramic high-cycle regenerator provides extra energy for the thermal conversion...
-
Action-reaction based synthesis of acoustic wavefield equations
PublikacjaThe analysis of acoustic fields is usually based on the well-known mathematics of second order partial differential equations called wave equations. The author explores the duality and symmetry of linear fluid mechanics and develops two distinct equations of acoustics on the basis of a causal approach to local small-scale phenomena. Wavefields that are solutions of these equations have different composition, the spherical pressure...
-
Detection of Water on Road Surface with Acoustic Vector Sensor
PublikacjaThis paper presents a new approach to detecting the presence of water on a road surface, employing an acoustic vector sensor. The proposed method is based on sound intensity analysis in the frequency domain. Acoustic events, representing road vehicles, are detected in the sound intensity signals. The direction of the incoming sound is calculated for the individual spectral components of the intensity signal, and the components...
-
Acoustic Sensing Analytics Applied to Speech in Reverberation Conditions
PublikacjaThe paper aims to discuss a case study of sensing analytics and technology in acoustics when applied to reverberation conditions. Reverberation is one of the issues that makes speech in indoor spaces challenging to understand. This problem is particularly critical in large spaces with few absorbing or diffusing surfaces. One of the natural remedies to improve speech intelligibility in such conditions may be achieved through speaking...
-
Diatoms Biomass as a Joint Source of Biosilica and Carbon for Lithium-Ion Battery Anodes
PublikacjaThe biomass of one type cultivated diatoms (Pseudostaurosira trainorii), being a source of 3D-stuctured biosilica and organic matter—the source of carbon, was thermally processed to become an electroactive material in a potential range adequate to become an anode in lithium ion batteries. Carbonized material was characterized by means of selected solid-state physics techniques (XRD, Raman, TGA). It was shown that the pyrolysis...
-
Hydrogen production from biomass using dark fermentation
PublikacjaHydrogen applicability in the power, chemical and petrochemical industries is constantly growing. Efficientmethods of hydrogen generation from renewable sources, including waste products, are currently being de-veloped, even though hydrogen is mainly produced through steam reforming or thermal cracking of natural gasor petroleum fractions. In paper alternative methods of hydrogen production with a particular emphasis on darkfermentation...
-
Multifunctional catalyst-assisted sustainable reformation of lignocellulosic biomass into environmentally friendly biofuel and value-added chemicals
PublikacjaRapid urbanization is increasing the world's energy demand, making it necessary to develop alternative energy sources. These growing energy needs can be met by the efficient energy conversion of biomass, which can be done by various means. The use of effective catalysts to transform different types of biomasses will be a paradigm change on the road to the worldwide goal of economic sustainability and environmental protection. The...
-
Auto adaptation of mobile device characteristics to various acoustic conditions
PublikacjaThe proposed methodology of auto adaptation of the mobile device characteristics to various acoustic conditions is presented in the paper. The first goal of this study was to determine the parameters of the acoustic path of the mobile device, for both transmitting (speaker) and receiver (microphone). Results of the measurement of characteristics of mobile devices were presented. Information about characteristics of individual parts...
-
Empirical analyses of robustness of the square Msplit estimation
PublikacjaThe paper presents Msplit estimation as an alternative to methods in the class of robust M-estimation. The analysis conducted showed that Msplit estimation is highly efficient in the identification of observations encumbered by gross errors, especially those of small or moderate values. The classical methods of robust estimation provide then unsatisfactory results. Msplit estimation also shows high robustness to single gross errors...
-
total number and biomass of bacteria in drinking water distribution systems.
PublikacjaIn the vast water supply network using traditional methods of treatment it is often impossible to maintain a constant and acceptable microbiological quality of water. In Poland the main reason of bacterial re-growth is presence of organic matter and nutrients in the circulating water and prolonged water retention in the network systems due to the decrease of water consumption, which has been observed for the last 20 years. In the...
-
Measurements of acoustic crosstalk cancellation efficiency in mobile listening conditions
PublikacjaThe cancellation of acoustic crosstalk is employed to enhance the stereo image in mobile listening conditions. The implementation of the crosstalk cancellation algorithm in Matlab is introduced. The measurement signals and equipment are described. A practical setup employing a mobile computer and a head and torso simulator is employed. The results of the measurements provided conclusions regarding the employment of acoustic crosstalk...
-
Time-domine Dipole Fields in acoustic and Elektromagnetics
PublikacjaThe ultrawideband (UWB) radio technique presents a challenge not just for technology. The UWB carrier-free pulses act at a close distance, their electromagnetic fields being very different from classic monochromatic plane wave. The author proposes to adapt a time-domian approach to analysis of broadband spherical fields, both acoustic and electromagnetic, in fundamental cases of quasi-point physical sources.
-
Shallow Water Experiment of OFDM Underwater Acoustic Communications
PublikacjaThe large variability of communication properties of underwater acoustic channels, and especially the strongly varying instantaneous conditions in shallow waters, is a challenge for the designers of underwater acoustic communication (UAC) systems. The use of phase modulated signals does not allow reliable data transmission through such a tough communication channel. However, orthogonal frequency-division multiplexing (OFDM), being...
-
Microstructure–Property Relationship of Polyurethane Foams Modified with Baltic Sea Biomass: Microcomputed Tomography vs. Scanning Electron Microscopy
PublikacjaIn this paper, novel rigid polyurethane foams modified with Baltic Sea biomass were compared with traditional petro-based polyurethane foam as reference sample. A special attention was focused on complex studies of microstructure, which was visualized and measured in 3D with high-resolution microcomputed tomography (microCT) and, as commonly applied for this purpose, scanning electron microscopy (SEM). The impact of pore volume,...
-
INFLUENCE OF TEMPERATURE ON THE ACTIVITY OF ANAMMOX GRANULAR BIOMASS - SHORT AND LONG-TERM ASPECT
PublikacjaThe aim of this study was to determine a short-term and long-term effect of temperature on the anammox process rate and determination of temperature coefficients in the Arrhenius and Ratkowski equations. The short-term effects of temperature on the anammox biomass were investigated in batch tests at ten different temperatures in the range of 10-55 ̊C. The maximum rate 1.3 gN (gVSS·d)-1 observed at 40 ̊C. The minimum rate, close...
-
Propagation of acoustic pulses in some fluids with yield stress
PublikacjaThis study is devoted to the derivation of approximate equations governing acoustic pulses in flows with yieldstress, including some time-dependent flows with a slow dependence on time of yield stress and apparent viscosity. Themodeling of yield stress and apparent viscosity in the vicinity of a zero deformation rate allows us to consider a thixotropicfluid as a Bingham plastic with coefficients that are dependent on time. The...