Filtry
wszystkich: 423
wybranych: 401
Wyniki wyszukiwania dla: EXPERIMENTAL METHODS
-
NONSTRUCTURAL STIFFNESS ASSESSMENT IN INSTRUMENTED STEEL BUILDINGS
PublikacjaLateral stiffness of nonstructural components may significantly influence the initial stiffness of the entire structure and consequently alter its dynamic characteristics. While methods for simulating structural members are well-established, approaches for modeling nonstructural components that also participate in seismic response are notably less developed. In this paper a simplified, physically-intuitive approach for estimating...
-
New empirical correlations for the viscosity of selected organic phase change materials
PublikacjaAlthough there are many methods and instruments for measuring viscosity, it is still difficult to determine a reliable value of the dynamic viscosity of complex chemicals such as paraffins and fatty acids. This is due to the complex and heterogeneous structure of these compounds in the case of commercial products. On the other hand, the measuring instrument should be selected very carefully, including its measuring principle and...
-
Numerical analyses of novel prefabricated structural wall panels in residential buildings based on laboratory tests in scale 1:1
PublikacjaThe paper presents experimental and numerical investigations on novel prefabricated composite building wall panels for residential building constructions. The wall panels were composed of reinforced concrete ribbed elements with the core from the EPS foam as the thermal insulation. The wall panels in the full-scale 1:1 were subjected to vertical loads. In the first step, the experiments were analysed with simple usual static methods....
-
Model studies to identify input parameters of an algorithm controlling electric supply/consumption process by underground iron ore enterprises
PublikacjaPurpose is the development of the research format of a mathematical model to select and assess input parameters of an algorithm controlling distribution of electric energy flows in the monitoring structure of electricity supply/ consumption by using equipment of mining enterprises engaged in underground iron ore raw materials extraction. Methods. The analytical research involved a theory of random processes adapted to the real...
-
Identification of category associations using a multilabel classifier
PublikacjaDescription of the data using categories allows one to describe it on a higher abstraction level. In this way, we can operate on aggregated groups of the information, allowing one to see relationships that do not appear explicit when we analyze the individual objects separately. In this paper we present automatic identification of the associations between categories used for organization of the textual data. As experimental data...
-
Effect of Surface Treatment of Halloysite Nanotubes (HNTs) on the Kinetics of Epoxy Resin Cure with Amines
PublikacjaThe epoxy/clay nanocomposites have been extensively considered over years because of their low cost and excellent performance. Halloysite nanotubes (HNTs) are unique 1D natural nanofillers with a hollow tubular shape and high aspect ratio. To tackle poor dispersion of the pristine halloysite (P-HNT) in the epoxy matrix, alkali surface-treated HNT (A-HNT) and epoxy silane functionalized HNT (F-HNT) were developed and cured with...
-
Simultaneous voltammetric determination of Cd2+, Pb2+, and Cu2+ ions captured by Fe3O4@SiO2 core-shell nanostructures of various outer amino chain length
PublikacjaIn the present study, we examined a novel functionalised magnetic nanoparticles Fe3O4@SiO2-Nn as a nano adsorbent for binding of Cd2+, Pb2+, Cu2+ ions in an aqueous solution. First, we obtained the nanoparticles functionalised with various carbon chains containing different number of amino groups: (3-amino)propyltriethoxysilane (Fe3O4@SiO2-N1), N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (Fe3O4@SiO2-N2) and N1-(3-trimethoxysilylpropyl)diethylenetriamine...
-
Uproszczone metody obliczania wyboczenia silosów z blachy falistej wzmocnionych słupami na podstawie analizy MES i wyników doświadczalnych
PublikacjaRozprawa doktorska dotyczy zagadnienia stateczności i nośności granicznej stalowych silosów z płaszczem z blachy falistej wzmocnionych pionowymi słupami. Przeprowadzono zaawansowane analizy numeryczne MES oraz badania doświadczalne dotyczące wyboczenia/stateczności analizowanych silosów. Analizy numeryczne zostały przeprowadzone w zakresie liniowej oraz nieliniowej analizy stateczności, z uwzględnieniem wstępnych imperfekcji geometrycznych...
-
Comparison and Analysis of Service Selection Algorithms
PublikacjaIn Service Oriented Architecture, applications are developed by integration of existing services in order to reduce development cost and time. The approach, however, requires algorithms that select appropriate services out of available, alternative ones. The selection process may consider both optimalization requirements, such as maximalization of performance, and constraint requirements, such minimal security or maximum development...
-
Estimation of nonstructural stiffness in instrumented steel frames
PublikacjaLateral stiffness of nonstructural components may significantly influence the initial stiffness of the entire structure and consequently alter its dynamic characteristics. While methods for simulating structural members are well-established, approaches for modeling nonstructural components that also participate in seismic response are notably less developed. In this paper a simplified, physically-intuitive approach for estimating...
-
Full scale CFD seakeeping simulations for case study ship redesigned from V-shaped bulbous bow to X-bow hull form
PublikacjaIncreasing propulsion efficiency, safety, comfort and operability are of the great importance, especially for small ships operating on windy sites like the North Sea and the Baltic Sea. Seakeeping performance of ships and offshore structures can be analysed by different methods and the one that is becoming increasingly important is CFD RANS. The recent development of simulation techniques together with rising HPC accessibility...
-
Multiaspect measurement analysis of breaking energy recovery
PublikacjaNowadays the issue of electric energy saving in public transport is becoming a key area of interest, which is connected both with a growth of environmental awareness in the society and an increase in the prices of fuel and electricity. That is why the reduction of energy consumption by increasing electrified urban transport, such as trams, trolleybuses, light rail and underground is becoming an increasingly important issue. Energy...
-
Next generation automatic IP configuration deployment issues
PublikacjaAlthough Dynamic Host Configuration Protocol for IPv6 (DHCPv6) protocol was defined in 2003, it was designed as a framework rather than a complete solution to the automatic configuration in IPv6 networks. There are still some unsolved problems and new options yet to be defined. One example of such case is Fully Qualified Domain Name (FQDN) option, which final version has been published in late 2007. It describes DHCPv6 client...
-
AC motor feeding cable consequences on EMC performance of ASD
PublikacjaHigh level of conducted EMI emissions of adjustable speed drives (ASD) is one of the most difficult problems in contemporary applications. Many investigations are carried out in order to find more effective methods allowing to predict this emission at early stage of design, and therefore to predict adequate countermeasures. This paper deals with the method which allows to estimate by simulation the influence of motor feeding cable...
-
Immittance Studies of Bi6Fe2Ti3O18 Ceramics
PublikacjaResults of studies focusing on the electric behavior of Bi6Fe2Ti3O18 (BFTO) ceramics are reported. BFTO ceramics were fabricated by solid state reaction methods. The simple oxides Bi2O3, TiO2, and Fe2O3 were used as starting materials. Immittance spectroscopy was chosen as a method to characterize electric and dielectric properties of polycrystalline ceramics. The experimental data were measured in the frequency range D = (101–107)...
-
QRS Morphology-Based EDR Signal—Factors Determining its Properties
PublikacjaRespiration-induced signals contain a clinically significant information. It could be obtained utilizing both direct and indirect methods. ECG-Derived Respiration (EDR) method is the latter one. However, in this case, two approaches could be distinguished. First one is based on determining changes in the morphology of QRS complexes while the second one is based on the Respiratory Sinus Arrhythmia (RSA) mechanism. The former approach...
-
A review on application of artificial neural network (ANN) for performance and emission characteristics of diesel engine fueled with biodiesel-based fuels
PublikacjaBiodiesel has been emerging as a potential and promising biofuel for the strategy of reducing toxic emissions and improving engine performance. Computational methods aiming to offer numerical solutions were inevitable as a study methodology which was sometimes considered the only practical method. Artificial neural networks (ANN) were data-processing systems, which were used to tackle many issues in engineering and science, especially...
-
Consideration of Pseudo Strain Energy in Determination of Fatigue Life and Microdamage Healing of Asphalt Mastics
PublikacjaRest periods between cyclic loads can lead to recovery of damage and extension of fatigue life. This phenomenon is referred to as healing. Healing is clearly observed in bituminous materials, such as asphalt mastics, which belong to the components of asphalt mixtures. Due to the nature of road pavement traffic loading, which is characterized by series of intermittent pulses with rest periods, consideration of healing is necessary...
-
Analysis of Modal Parameters Using a Statistical Approach for Condition Monitoring of the Wind Turbine Blade
PublikacjaThe primary objective of the presented paper is the numerical and experimental investigation related to developing a useful diagnostic method, which can be used for determining the site and size of damage in laminated shells of wind turbine blades. The described detection technique is based on the analysis of low frequencies bending vibrations mode shapes of rotor blades. The authors used the commonly applied statistics methods...
-
Nanokrystaliczne warstwy ceramiczne otrzymywane metodą pirolizy aerozolowej w tlenkowych ogniwach paliwowych
PublikacjaNiniejsza rozprawa doktorska dotyczy badań materiałów wytwarzanych w postaci cienkich, nanokrystalicznych warstw ceramicznych metodą pirolizy aerozolowej dla zastosowań w tlenkowych ogniwach paliwowych (SOFC). Badane są trzy możliwe obszary zastosowań wytwarzanych warstw tj. osadzanie powłok ochronnych na stalowych interkonektorach dostarczających gazy do elektrody tlenowej, wytwarzanie bariery ochronnej zapobiegającej dyfuzji...
-
ECHOES REDUCTION DURING DIGITAL DATA TRANSMISSION IN HYDROACOUSTIC CHANNEL – LABORATORY EXPERIMENT
PublikacjaThe possibility of using a hydroacoustic channel for digital data transmission is very limited. This is due to the effect of multipath propagation of the emitted acoustic wave and the damping of the mechanical wave in this medium, which increase with frequency. The first of these phenomena results in inter-symbol interference disturbances in data transmission systems, including even hundreds of symbols. Due to the number of reflections...
-
Full-scale CFD simulations for the determination of ship resistance as a rational, alternative method to towing tank experiments
PublikacjaResults of ship resistance predictions obtained from towing tank experiments are affected by the method used to extrapolate from a model scale to a ship scale. Selection of method to determine a form factor is subjective and the extrapolation method is accurate for typical hull forms. For innovative hull forms the proper method for calculating the form factor is questionable. Moreover, the influence of the extrapolation method...
-
Waterborne polyesters partially based on renewable resources
PublikacjaA new experimental approach for preparing biobased, water-soluble polyesters via titanium(IV) n-butoxide-catalyzed bulk polycondensation is presented. In the described method polymers were obtained from isosorbide, maleic anhydride and poly(ethylene glycol). The chemical structure of the synthesized polyesters was confirmed using 2D NMR spectroscopy and by titration methods. Careful analysis of 2D NMR spectra viz. Correlation Spectra...
-
Desirability-based optimization of dual-fuel diesel engine using acetylene as an alternative fuel
Publikacjahe study examined the dual-fuel engine performance employing acetylene gas as primary fuel and diesel as pilot fuel. The engine's operational parameters were adjusted using the Box-Behnken design, and the results were recorded. The best operating settings were yielded as 81.25 % engine load, 4.48 lpm acetylene gas flow rate and the compression ratio were 18. At this optimized setting the BTE was 27.1 % and the engine emitted 360...
-
High resolution X-ray diffractometry and reflectometry of semiconductor nano- and micro- structures based on X-ray refractive optics
PublikacjaIn this thesis proposed, discussed and studied novel synchrotron X-ray diffractometry and reflectometry methods based on a refractive optics. The experimental results obtained from the ID06 beamline at ESRF, Grenoble, France are presented and analyzed in this work to demonstrate a high angular and space resolution in addition to the opportunity to manage in situ and on operando experiments with the help of proposed X-ray optical...
-
Photosensitive and pH-dependent activity of pyrazine-functionalized carbazole derivative as promising antifungal and imaging agent
PublikacjaCarbazole skeleton plays a significant role as a structural scaffold of many pharmacologically active compounds. Pyrazine-functionalized carbazole derivative was constructed by coupling 2-amino-5-bromo-3-methylaminepyrazine (ABMAP) into 3 and 6 positions of the carbazole ring. Multi-experimental methods were used, e.g., potentiometric, spectroscopic (ATR, UV, XRD powder,1H and13C NMR), electrochemical (cyclic voltammetry), and...
-
Effect of temperature and composition on physical properties of deep eutectic solvents based on 2-(methylamino)ethanol – measurement and prediction
PublikacjaNovel deep eutectic solvents were synthesized using 2-(methylamino)ethanol as hydrogen bond donor with tetrabutylammonium bromide or tetrabutylammonium chloride or tetraethylammonium chloride as hydrogen bond acceptors. Mixtures were prepared at different molar ratios of 1:6, 1:8 and 1:10 salt to alkanolamine and then Fourier Transform Infrared Spectroscopy measurements were performed to confirm hydrogen bonds interactions between...
-
Modelling charge transfer processes in C2+ -tetrahydrofuran collision for ion-induced radiation damage in DNA building blocks
PublikacjaInvestigations of collision-induced processes involving carbon ions and molecules of biological interest in particular DNA building blocks, are crucial to model the effect of radiation on cells in order to improve medical treatments for cancer therapy. Using carbon ions appears to be one of the most efficient ways to increase biological effectiveness to damage cancerous cells by irradiating deep-seated tumors. Therefore, interest...
-
Space Vector Pulsewidth Modulation Strategy for Multilevel Cascaded H-Bridge Inverter With DC-Link Voltage Balancing Ability
PublikacjaSpace vector pulsewidth modulation (SVPWM) algorithms for cascaded H-bridge multilevel (CHB ML) inverter usually provide the possibility of using several combinations of active voltage vectors to generate the same output voltage vector. For preselected H-bridges, some of them may generate output voltages opposite to the assumed direction. This results in the change of the dc-link voltages of these H-bridges in the opposite direction...
-
A New Approach to Assess Quality of Motion in Functional Task of Upper Limb in Duchenne Muscular Dystrophy
Publikacja(1) Background: This study presents a new method for the motion quantitative analysis of Duchenne muscular dystrophy patients (DMD) performing functional tasks in clinical conditions. (2) Methods: An experimental study was designed to define how different levels of external mass (light and heavy) influence the performance of the upper limbs of a tested DMD and reference subject (RS) during horizontal movements (level of the waist)...
-
Inverse surrogate modeling for low-cost geometry scaling of microwave and antenna structures
PublikacjaPurpose–The purpose of this paper is to investigate strategies for expedited dimension scaling ofelectromagnetic (EM)-simulated microwave and antenna structures, exploiting the concept of variable-fidelity inverse surrogate modeling.Design/methodology/approach–A fast inverse surrogate modeling technique is described fordimension scaling of microwave and antenna structures. The model is established using referencedesigns obtained...
-
The Positioning Accuracy of BAUV Using Fusion of Data from USBL System and Movement Parameters Measurements
PublikacjaThe article presents a study of the accuracy of estimating the position coordinates of BAUV (Biomimetic Autonomous Underwater Vehicle) by the extended Kalman filter (EKF) method. The fusion of movement parameters measurements and position coordinates fixes was applied. The movement parameters measurements are carried out by on-board navigation devices, while the position coordinates fixes are done by the USBL (Ultra Short Base...
-
New synthesis route of highly porous InxCo4Sb12 with strongly reduced thermal conductivity
PublikacjaHighly porous, In-filled CoSb3 skutterudite materials with an attractive thermoelectric figure of merit (ZT * 1) and corresponding dense samples were fabricated through the cost-effective method of reduction in oxides in dry hydrogen and the pulsed electric current sintering (PECS) method, respectively. The reduction process was described in detail using in situ thermogravimetric analysis of Co2O3, Sb2O3 and In(NO3)35H2O separately...
-
The influence of reactions conditions on aggregation of dyes used in biochemistry
PublikacjaSelf-association of dyes and related substances is a very important phenomenon in many fields of applied chemistry. It is also fundamental model reaction of many kinds of molecular interactions such as the micelle formation of amphiphilic substances and the binding of small organic molecules to macromolecules. In spite of many studies concerning the dimerization equilibria of dyes and related substances, the mechanism seems not...
-
Ionic liquids for nano- and microstructures preparation. Part 1: Properties and multifunctional role
PublikacjaIonic liquids (ILs) are a broad group of organic salts of varying structure and properties, used in energy conversion and storage, chemical analysis, separation processes, as well as in the preparation of particles in nano- and microscale. In material engineering, ionic liquids are applied to synthesize mainly metal nanoparticles and 3D semiconductor microparticles. They could generally serve as a structuring agent or as a reaction...
-
Micropatterning of BiVO 4 Thin Films Using Laser-Induced Crystallization
PublikacjaRelatively high temperatures even up to 500 °C are required to obtain bismuth vanadate (BiVO4) films with the scheelite monoclinic (s-m) structure that shows the highest photocatalytic activity. This requirement limits the possible choice of substrates. Moreover, high quality thin layers of crystalline BiVO4 cannot be prepared with current methods. In this study a light-induced crystallization approach is presented, which is a...
-
S-scheme heterojunction Bi2O3-ZnO/Bentonite clay composite with enhanced photocatalytic performance
PublikacjaThe industrial waste water is always a bottleneck problem in the modern civilization of the present era. In a quest to develop effective methods for the elimination of lethal pollutants from the waste water and water remediation, this work is focused on the development of a rapid and proficient approach for preparing supported binary metal oxide catalyst for photocatalytic advance oxidation process used in waste water treatment...
-
Material Parameters Identification of Historic Lighthouse Based on Operational Modal Analysis
PublikacjaIn the present paper, the identification of the material parameters of a masonry lighthouse is discussed. A fully non-invasive method was selected, in which the material properties were determined via numerical model validation applied to the first pair of natural frequencies and their related mode shapes, determined experimentally. The exact structural model was built by means of the finite element method. To obtain experimental...
-
Numerical Issues and Approximated Models for the Diagnosis of Transmission Pipelines
PublikacjaThe chapter concerns numerical issues encountered when the pipeline flow process is modeled as a discrete-time state-space model. In particular, issues related to computational complexity and computability are discussed, i.e., simulation feasibility which is connected to the notions of singularity and stability of the model. These properties are critical if a diagnostic system is based on a discrete mathematical model of the flow...
-
RESEARCH OF HYDRAULIC PISTON PUMPS’ START-UP IN LOW AMBIENT TEMPERATURES
PublikacjaStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of increase of resistance of cold oil flow in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump...
-
Deep eutectic solvent-based shaking-assisted extraction for determination of bioactive compounds from Norway spruce roots
PublikacjaPolyphenolic compounds play an essential role in plant growth, reproduction, and defense mechanisms against pathogens and environmental stresses. Extracting these compounds is the initial step in assessing phytochemical changes, where the choice of extraction method significantly influences the extracted analytes. However, due to environmental factors, analyzing numerous samples is necessary for statistically significant results,...
-
Bacteriophages as potential tools for use in antimicrobial therapy and vaccine development
PublikacjaThe constantly growing number of people suffering from bacterial, viral, or fungal infections, parasitic diseases, and cancers prompts the search for innovative methods of disease prevention and treatment, especially based on vaccines and targeted therapy. An additional problem is the global threat to humanity resulting from the increasing resistance of bacteria to commonly used antibiotics. Conventional vaccines based on bacteria...
-
Revisiting the estimation of cutting power with different energetic methods while sawing soft and hard woods on the circular sawing machine: a Central European case
PublikacjaIn the classical approaches, used in Central Europe in practice, cutting forces and cutting power in sawing processes of timber are commonly computed by means of the specific cutting resistance kc. It needs to be highlighted that accessible sources in handbooks and the scientific literature do not provide any data about wood provenance, nor about cutting conditions, in which cutting resistance has been empirically determined. In...
-
Sustainability of Civil Structures through the Application of Smart Materials: A Review
PublikacjaEvery year, structural flaws or breakdowns cause thousands of people to be harmed and cost billions of dollars owing to the limitations of design methods and materials to withstand extreme earthquakes. Since earthquakes have a significant effect on sustainability factors, there is a contradiction between these constraints and the growing need for more sustainable structures. There has been a significant attempt to circumvent...
-
Fouling mechanisms in anoxic-aerobic sequencing batch membrane bioreactor based on adapted Hermia models and main foulant characteristics
PublikacjaVarious derivatives of Hermia models (complete pore blocking, intermediate pore blocking, cake layer formation, and standard pore blocking) and different assessments of foulant characteristics have long been used to determine the membrane fouling mechanisms. Accordingly, this study aims to adapt Hermia models and their combination according to the operating conditions of an anoxic-aerobic sequencing batch membrane bioreactor (A/O-SBMBR)....
-
Feature Weighted Attention-Bidirectional Long Short Term Memory Model for Change Detection in Remote Sensing Images
PublikacjaIn remote sensing images, change detection (CD) is required in many applications, such as: resource management, urban expansion research, land management, and disaster assessment. Various deep learning-based methods were applied to satellite image analysis for change detection, yet many of them have limitations, including the overfitting problem. This research proposes the Feature Weighted Attention (FWA) in Bidirectional Long...
-
Green monoterpenes based deep eutectic solvents for effective BTEX absorption from biogas
PublikacjaThe combustion of biogas which contains significant amounts of monoaromatic hydrocarbons, i.e. benzene, ethylbenzene, toluene, and xylene (BTEX) can cause many technological, environmental, and health problems. Therefore, in these studies, a new physical absorption method based on deep eutectic solvents (DES) consisting of monoterpenes and carboxylic acids was developed for BTEX removal. A total of 39 DES were synthesized, of which...
-
Adversarial attack algorithm for traffic sign recognition
PublikacjaDeep learning suffers from the threat of adversarial attacks, and its defense methods have become a research hotspot. In all applications of deep learning, intelligent driving is an important and promising one, facing serious threat of adversarial attack in the meanwhile. To address the adversarial attack, this paper takes the traffic sign recognition as a typical object, for it is the core function of intelligent driving. Considering...
-
Eu2Mg3Bi4: Competing Magnetic Orders on a Buckled Honeycomb Lattice
PublikacjaThe honeycomb lattice and its derived variants provide information on modeling and designing quantum magnets. A novel magnetic material, Eu2Mg3Bi4, which stabilizes in a previously unknown buckled honeycomb lattice, was discovered by high-pressure and high-temperature methods. We report here on the synthesis exploration of pure single crystals, structural determination of the buckled honeycomb lattice of europium moments, and experimental observation...
-
Thermal Energy Storage with PCMs in Shell-and-Tube Units: A Review
PublikacjaThe paper presents a survey of the experimental and numerical studies of shell-and-tube systems in which phase change material (PCM) is used. Due to the multitude of design solutions for shell-and-tube systems, the emphasis is placed on double-tube (DT), triplex-tube (TT), and multitube (MT) units. Additionally, only single-pass systems are considered. Particular attention is paid to the method of heat transfer intensification....