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Wyniki wyszukiwania dla: UNCERTAINTY OF MASS FLOW MEASUREMENT
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Novel fast analytical method for indirect determination of MCPD fatty acid esters in edible oils and fats based on simultaneous extraction and derivatization
PublikacjaA novel method for indirect determination of MCPD esters levels in lipid samples has been developed. The method is based on combination of extraction and derivatisation in the same sample preparation step. It is achieved by the application of diethyl ether as extraction solvent for isolation of released from esterified forms analytes from water phase and dilution solvent for solid PBA – derivatisation agent. It is a noteworthy...
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Reliable data-driven modeling of high-frequency structures by means of nested kriging with enhanced design of experiments
PublikacjaData-driven (or approximation) surrogate models have been gaining popularity in many areas of engineering and science, including high-frequency electronics. They are attractive as a way of alleviating the difficulties pertinent to high computational cost of evaluating full-wave electromagnetic (EM) simulation models of microwave, antenna, and integrated photonic components and devices. Carrying out design tasks that involve massive...
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Multi-fidelity robust aerodynamic design optimization under mixed uncertainty
PublikacjaThe objective of this paper is to present a robust optimization algorithm for computationally efficient airfoil design under mixed (inherent and epistemic) uncertainty using a multi-fidelity approach. This algorithm exploits stochastic expansions derived from the Non-Intrusive Polynomial Chaos (NIPC) technique to create surrogate models utilized in the optimization process. A combined NIPC expansion approach is used, where both...
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Reliable computationally-efficient behavioral modeling of microwave passives using deep learning surrogates in confined domains
PublikacjaThe importance of surrogate modeling techniques has been steadily growing over the recent years in high-frequency electronics, including microwave engineering. Fast metamodels are employed to speedup design processes, especially those conducted at the level of full-wave electromagnetic (EM) simulations. The surrogates enable massive system evaluations at nearly EM accuracy and negligible costs, which is invaluable in parameter...
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Effects of full displacement pile installation on the stress and deformation state of surrounding soil: review
PublikacjaSeveral field and model tests have been conducted to investigate the impact of pile installation on bearing capacity. However, little is known about how piles behave during installation, how they interact with the surrounding soil, and how this affects sandy soil properties. This review paper investigates the effect of pile driving on surrounding sandy soil as it compacts sandy soil near to the pile. For this purpose, various related...
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Predicting bankruptcy with the use of macroeconomic variables
PublikacjaRegarding the current global financial crisis, the firms can expect the increased uncertainty of their existence. The relevant literature includes extensive studies on bankruptcy prediction. Studies show that the most popular method used for prediction of firms' failures are discriminant analyses (30,3% of all models), then logit and probit models (21,3%), which all three are parametric models. The nature, the structure of the...
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Design-oriented modeling of antenna structures by means of two-level kriging with explicit dimensionality reduction
PublikacjaThe employment of full-wave electromagnetic (EM) analysis is a practical necessity in the design of contemporary antenna structures. This is because simpler models are generally not available or of limited accuracy. At the same time, EM-based design is computationally expensive. Consequently, the ways of accelerating tasks such as parametric optimization or uncertainty quantification have to be sought. A possible workaround that...
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Improved Modeling of Microwave Structures Using Performance-Driven Fully-Connected Regression Surrogate
PublikacjaFast replacement models (or surrogates) have been widely applied in the recent years to accelerate simulation-driven design procedures in microwave engineering. The fundamental reason is a considerable—and often prohibitive—CPU cost of massive full-wave electromagnetic (EM) analyses related to solving common tasks such as parametric optimization or uncertainty quantification. The most popular class of surrogates are data-driven...
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Expedited Acquisition of Database Designs for Reduced-Cost Performance-Driven Modeling and Rapid Dimension Scaling of Antenna Structures
PublikacjaFast replacement models have been playing an increasing role in high-frequency electronics, including the design of antenna structures. Their role is to improve computational efficiency of the procedures that normally entail large numbers of expensive full-wave electromagnetic (EM) simulations, e.g., parametric optimization or uncertainty quantification. Recently introduced performance-driven modeling methods, such as the nested...
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Strategic aspects in spatial planning - theory and practice in largest cities of Poland
PublikacjaThe rate of changes and the growing uncertainty rise to the need for a strategic approach to development planning, which is active and flexible in relation to the changing reality. Strategic planning, occurring in companies, was adapted by the social-economic development planning of self-government units. However, there are difficulties in applying the strategic planning in the spatial planning and integration of the two forms...
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Risk Modelling with Bayesian Networks - Case Study: Construction of Tunnel under the Dead Vistula River in Gdansk
PublikacjaThe process of decision-making in public procurement of construction projects during the preparation and implementation phases ought to be supported by risk identification, assessment, and management. In risk assessment one has to take into account factors that lead to risk events (background info), as well as the information about the risk symptoms (monitoring info). Typically once the risks have been assessed a decision-maker...
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Tolerance-Aware Optimization of Microwave Circuits by Means of Principal Directions and Domain-Restricted Metamodels
PublikacjaPractical microwave design is most often carried out in the nominal sense. Yet, in some cases, performance degradation due to uncertainties may lead to the system failing to meet the prescribed specifications. Reliable uncertainty quantification (UQ) is therefore important yet intricate from numerical standpoint, especially when the circuit at hand is to be evaluated using electromagnetic (EM) simulation tools. Tolerance-aware...
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Variable‐fidelity modeling of antenna input characteristics using domain confinement and two‐stage Gaussian process regression surrogates
PublikacjaThe major bottleneck of electromagnetic (EM)-driven antenna design is the high CPU cost of massive simulations required by parametric optimization, uncertainty quantification, or robust design procedures. Fast surrogate models may be employed to mitigate this issue to a certain extent. Unfortunately, the curse of dimensionality is a serious limiting factor, hindering the construction of conventional data-driven models valid over...
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Design-Oriented Two-Stage Surrogate Modeling of Miniaturized Microstrip Circuits with Dimensionality Reduction
PublikacjaContemporary microwave design heavily relies on full-wave electromagnetic (EM) simulation tools. This is especially the case for miniaturized devices where EM cross-coupling effects cannot be adequately accounted for using equivalent network models. Unfortunately, EM analysis incurs considerable computational expenses, which becomes a bottleneck whenever multiple evaluations are required. Common simulation-based design tasks include...
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Probabilistic seismic assessment of RC box-girder highway bridges with unequal-height piers subjected to earthquake-induced pounding
PublikacjaThis paper uses the probabilistic seismic assessment to study the effects of pounding and irregularity on the seismic behavior of typical concrete box-girder bridges with four levels of altitudinal irregularity. To extend the results for all bridges in the same class, uncertainty related to the earthquake, structural geometries, and materials are considered. Pounding is likely to take place in two cases: the first one concerns...
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Functional safety and reliability analysis methodoloogy for hazardous industrial plants
PublikacjaThis monograph is devoted to current problems and methods of the functional safety and reliability analyses of the programmable control and protection systems for industrial hazardous plants. The results of these analyses are useful in the process of safety management in life cycle, for effective reducing relevant risks at the design stage, and then controlling these risks during the operation of given installation. The methodology...
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ISLAMIC TAKAFUL: CZY SKUTECZNIE ZASTĄPIŁ UBEZPIECZENIA KOMERCYJNE? : ISLAMIC TAKAFUL: HAS IT SUCCESSFULLY SUBSTITUTED CONVENTIONAL INSURANCE?
PublikacjaIslamic finance is a fast developing sector mainly present in the Middle East, South-East Asia, Central Asia and to a smaller extent in Africa and Central Europe. Together with the rebirth of Islam in the second half of the 20th century, Islamic finance tends to cover the economic needs of all Muslims (including insurances). The Islamic finance system is based on several principles including three main prohibitions: Gharar (deceptive uncertainty),...
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Low-Cost and Highly-Accurate Behavioral Modeling of Antenna Structures by Means of Knowledge-Based Domain-Constrained Deep Learning Surrogates
PublikacjaThe awareness and practical benefits of behavioral modeling methods have been steadily growing in the antenna engineering community over the last decade or so. Undoubtedly, the most important advantage thereof is a possibility of a dramatic reduction of computational expenses associated with computer-aided design procedures, especially those relying on full-wave electromagnetic (EM) simulations. In particular, the employment of...
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Edible Lepidoptera as human foods – a comprehensive review
PublikacjaAs the global population continues to grow, traditional protein sources like meat and fish are becoming increasingly unsustainable due to their environmental impact. Edible insects, on the other hand, are highly nutritious, require minimal resources to produce, and emit significantly fewer greenhouse gases than traditional livestock. Lepidoptera, one of the most diverse insect orders, contains some popular edible species that have...
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Machine Learning Assisted Interactive Multi-objectives Optimization Framework: A Proposed Formulation and Method for Overtime Planning in Software Development Projects
PublikacjaMachine Learning Assisted Interactive Multi-objectives Optimization Framework: A Proposed Formulation and Method for Overtime Planning in Software Development Projects Hammed A. Mojeed & Rafal Szlapczynski Conference paper First Online: 14 September 2023 161 Accesses Part of the Lecture Notes in Computer Science book series (LNAI,volume 14125) Abstract Software development project requires proper planning to mitigate risk and...
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A novel hybrid adaptive framework for support vector machine-based reliability analysis: A comparative study
PublikacjaThis study presents an innovative hybrid Adaptive Support Vector Machine - Monte Carlo Simulation (ASVM-MCS) framework for reliability analysis in complex engineering structures. These structures often involve highly nonlinear implicit functions, making traditional gradient-based first or second order reliability algorithms and Monte Carlo Simulation (MCS) time-consuming. The application of surrogate models has proven effective...
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Investigation of Acoustic Properties of Poroelastic Asphalt Mixtures in Laboratory and Field Conditions
PublikacjaMeasures for the improvement of acoustic conditions in the vicinity of roads include the construction of pavement structures with low-noise surfaces with optimal macrotexture and the highest possible sound absorption coefficient. Laboratory evaluation of acoustic properties of a designed asphalt mixture before its placement in the pavement is a good solution. Currently, the most popular method for the determination of the sound...
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Estimation of Broadband Complex Permeability Using SIW Cavity-Based Multimodal Approach
PublikacjaIn this article, an attractive multimodal substrate integrated waveguide (SIW) based methodology is presented for the characterization of magnetic materials in the broadband microwave frequency. The proposed approach employs a modified feed under-coupled SIW cavity instead of conventional feed over-coupled multiple SIW cavities; it uses the modified closedform expression, developed from the first principle to consider the effect...
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Small city and a bridge. Landscape perspective
PublikacjaThe aim of the paper is to present the problems connected with the location of big infrastructure objects; like bridges; in close neighbourhood to the small cities located in valuable environment and landscape; and the ways to minimize the potential threats. The case study of the small town Wyszogrod in central Poland will be presented to illustrate the values of the environment and landscape; which could have been easily destroyed...
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Towards a method for detecting large roll motions suitable for oceangoing ships
PublikacjaThe concept of autonomous merchant ships is quite recent. The increasing interest in autonomous vessels is nowadays calling for smart technologies that are supposed to replace the human actions on board. This involves troublesome issues related to ship safety. In the future, decision-making processes that are conventionally performed by human beings on board ship will be moved ashore to the control centre and maybe even completely...
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Experimental and computational study on mechanical behaviour of carpentry corner log joints
PublikacjaThis work concerns experimental and numerical research on carpentry joints used in historic wooden buildings in southeastern Poland and western Ukraine. These structures are mainly sacred buildings, and the types of corner log joints characteristic of this region are primarily saddle-notch and dovetail joints; thus, these two types of joints were analysed in this study. The modelling of historic timber structures is a complex...
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Expedited Yield Optimization of Narrow- and Multi-Band Antennas Using Performance-Driven Surrogates
PublikacjaUncertainty quantification is an important aspect of engineering design, also pertaining to the development and performance evaluation of antenna systems. Manufacturing tolerances as well as other types of uncertainties, related to material parameters (e.g., substrate permittivity) or operating conditions (e.g., bending) may affect the antenna characteristics. In the case of narrow- or multi-band antennas, this usually leads to...
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Modeling of TEC Variations Based on Signals from Near Zenith GNSS Satellite Observed by Dense Regional Network
PublikacjaCurrently the substantial successes in high-resolution ionospheric mapping is declared in many publications. Nevertheless, up to now there are no examples of dynamic visualization of TEC disturbances on regional scale with as high resolution as tropospheric models. Over the years, ionosphere has been modeling basing on the simple assumption, that it is a thin layer, which surrounds the Earth at some arbitrary height. However, the...
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Exploring the impact of cultural context on eye-tracking studies of architectural monuments in selected European cities: Sustainable heritage management.
PublikacjaSustainable management of architectural heritage requires conducting an inclusive diagnosis of users’ opinions, considering both residents and tourists as the recipients of urban space. Given the cultural diversity within these groups, proposing the use of eye-trackers (ET) as an alternative to traditional public consultation prompts the need to assess the method’s advantages and disadvantages. It remains uncertain whether individuals...
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Global EM-Driven Optimization of Multi-Band Antennas Using Knowledge-Based Inverse Response-Feature Surrogates
PublikacjaElectromagnetic simulation tools have been playing an increasing role in the design of contemporary antenna structures. The employment of electromagnetic analysis ensures reliability of evaluating antenna characteristics but also incurs considerable computational expenses whenever massive simulations are involved (e.g., parametric optimization, uncertainty quantification). This high cost is the most serious bottleneck of simulation-driven...
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Recent advances in high-frequency modeling by means of domain confinement and nested kriging
PublikacjaDevelopment of modern high-frequency components and circuits is heavily based on full-wave electromagnetic (EM) simulation tools. Some phenomena, although important from the point of view of the system performance, e.g., EM cross-coupling effects, feed radiation in antenna arrays, substrate anisotropy, cannot be adequately accounted for using simpler means such as equivalent network representations. Consequently, the involvement...
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Performance-Driven Surrogate Modeling of High-Frequency Structures
PublikacjaThe development of modern high-frequency structures, including microwave and antenna components, heavily relies on full-wave electromagnetic (EM) simulation models. Notwithstanding, EM-driven design entails considerable computational expenses. This is especially troublesome when solving tasks that require massive EM analyzes, parametric optimization and uncertainty quantification be-ing representative examples. The employment of...
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Expedited Yield-Driven Design of High-Frequency Structures by Kriging Surrogates in Confined Domains
PublikacjaUncertainty quantification is an important aspect of engineering design, also pertaining to the development and performance evaluation of high-frequency structures systems. Manufacturing tolerances as well as other types of uncertainties, related to material parameters (e.g., substrate permittivity) or operating conditions (e.g., bending) may affect the characteristics of antennas or microwave devices. For example, in the case...
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The Response of Selected Domestic Capital Markets on the Development of COVID-19 Pandemic – a Broader View
PublikacjaObjective: The study examines how the record of the first, hundredth, thousandth, ten-thousandth, one-hundred-thousandth, and millionth cases of COVID-19 affected investor behaviour in capital markets. It also looks at whether the month in which the first case was recorded in a given market affected the direction and strength of investor reactions. Lastly, it verifies whether the two announcements made by the WHO related to COVID-19...
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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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Szacowanie niepewności funkcji przetwarzania przetwornika LEM CT -5T metodą Monte Carlo
PublikacjaW referacie zaprezentowano metodologię szacowania niepewności funkcji przetwarzania przetwornika prądowego, na przykładzie przetwornika LEM CT-5T, przy zastosowaniu metody opartej na Przewodniku GUM, z zastosowaniem prawa propagacji niepewności oraz metody numerycznej Monte Carlo. Przedstawiono szczegółową analizę doboru rozkładu wielkości wejściowej. W przypadku metody Monte Carlo dobór rozkładu wielkości wejściowych jest bardzo...
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Szacowanie niepewności funkcji przetwarzania przetwornika LEM CT -5T metodą Monte Carlo
PublikacjaW referacie zaprezentowano metodologię szacowania niepewności funkcji przetwarzania przetwornika prądowego, na przykładzie przetwornika LEM CT-5T, przy zastosowaniu metody opartej na Przewodniku GUM z zastosowaniem prawa propagacji niepewności oraz metody numerycznej Monte Carlo. Przedstawiono szczegółową analizę doboru rozkładu wielkości wejściowej. W przypadku metody Monte Carlo dobór rozkładu wielkości wejściowych jest bardzo...
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Accurate Modeling of Antenna Structures by Means of Domain Confinement and Pyramidal Deep Neural Networks
PublikacjaThe importance of surrogate modeling techniques has been gradually increasing in the design of antenna structures over the recent years. Perhaps the most important reason is a high cost of full-wave electromagnetic (EM) analysis of antenna systems. Although imperative in ensuring evaluation reliability, it entails considerable computational expenses. These are especially pronounced when carrying out EM-driven design tasks such...
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Knowledge-based performance-driven modeling of antenna structures
PublikacjaThe importance of surrogate modeling techniques in the design of modern antenna systems has been continuously growing over the recent years. This phenomenon is a matter of practical necessity rather than simply a fashion. On the one hand, antenna design procedures rely on full-wave electromagnetic (EM) simulation tools. On the other hand, the computational costs incurred by repetitive EM analyses involved in solving common tasks...
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Affective Learning Manifesto – 10 Years Later
PublikacjaIn 2004 a group of affective computing researchers proclaimed a manifesto of affective learning that outlined the prospects and white spots of research at that time. Ten years passed by and affective computing developed many methods and tools for tracking human emotional states as well as models for affective systems construction. There are multiple examples of affective methods applications in Intelligent Tutoring Systems (ITS)....
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Static electric multipole susceptibilities of the relativistic hydrogenlike atom in the ground state: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function
PublikacjaThe ground state of the Dirac one-electron atom, placed in a weak, static electric field of definite $2^{L}$ polarity, is studied within the framework of the first-order perturbation theory. The Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B: At. Mol. Opt. Phys. 30, 825 (1997); erratum R. Szmytkowski, J. Phys. B: At. Mol. Opt. Phys. 30, 2747 (1997)] is used to derive closed-form analytical...
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Flow Maps and Flow Patterns of R1233zd(E) in a Circular Minichannel at Low, Medium and High Values of Saturation Pressure
PublikacjaThere is a gap in knowledge regarding the flow pattern of low-boiling working fluids in the range of high saturation temperatures (above 120°C) and medium and high reduced pressures (0.5-0.9). Data are present in the literature for similar values of reduced pressures, but for lower values of saturation temperature. This is due to the existing refrigeration applications of these working fluids. At high values of reduced pressure,...
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Numerical Simulations for Transonic Flow in Control Valve
PublikacjaResults of numerical simulations for transonic flow in control valve are presented. The valve is the main part of an adaptive pneumatic shock absorber. Flow structure in the valve domain and the influence of the flow non-uniformity in the valve on a mass flow rate is investigated. Numerical simulation results are compared with experimental data.
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Experimental study of flow boiling pressure drop and heat transfer of R1233zd(E) at moderate and high saturation temperatures
PublikacjaThe paper presents the results of experimental study of flow boiling of R1233zd(E) in minichannel at moderate and high saturation temperatures. The heat transfer coefficient and pressure drop were measured for flow boiling in a stainless steel tube with 2 mm inside diameter and a length of 300 mm. Experiment has been conducted for saturation temperatures ranging from 83 to 145 °C which corresponds to values of reduced pressures...
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Wyrażanie niepewności za pomocą przedziałów
PublikacjaZ perspektywy dwóch różnych interpretacji prawdopodobieństwa - klasycznej (częstościowej) i subiektywnej (bayesowskiej) oraz propozycji nowego przewodnika ustalającego zasady obliczania i wyrażania niepewności pomiaru (GUM), porównano sposoby komunikowania niepewności za pomocą przedziałów: ufności, bayesowskiego, objęcia, rozszerzenia.
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Stability Assessment of Coastal Cliffs Incorporating Laser Scanning Technology and a Numerical Analysis
PublikacjaWe investigated the cli coast in Jastrzebia Gora, Poland. The measurements that were taken between 2014 and 2018 by applying terrestrial, mobile, and airborne laser scanning describe a huge geometric modification involving dislocations in a 2.5 m range. Dierential maps and a volumetric change analysis made it possible to identify the most deformed cli’s location. Part of the monitoring of coastal change involved the measurement...
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An experimental investigation on the effect of new continuous core-baffle geometry on the mixed convection heat transfer in shell and coil heat exchanger
PublikacjaIn the article, the authors presented the influence of continuous core-baffle geometry at mixed convection heat transfer in shell and coil heat exchanger. Experiments were carried out for a large power range, i.e. from 100W to 1200W and mass flow rates ranging from 0.01 kg/s to 0.025 kg/s. During the experiments, the mass flow rate of cooling water, the temperature of water at the inlet and outlet as well as the wall temperature...
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Improvement of radiotracers experiments in mass transfer processes
PublikacjaThe greatest part of industrial mass transfer is based on continuous transportation of different substances throughout especially constructed installations. In that kind of practice, a flow of such mass in each part determines the process unit and can be described by the residence time distribution (RTD) of the substance inside this unit. This parameter may be evaluated by the properly arranged tracer experiment. It is worthwhile...
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Szacowanie niepewności pomiarowej układu do diagnostyki łożysk opartej na analizie mocy chwilowej
PublikacjaW artykule przedstawiono sposób szacowania niepewności układu pomiarowego, składającego się z dzielnika napięcia oraz bocznika, który wykorzystano do badań diagnostycznych łożysk silników indukcyjnych. Wyniki analizy metrologicznej pozwalają sprecyzować, jakiej niepewności pomiarowej można się spodziewać, dokonując badań diagnostycznych łożysk silników indukcyjnych w określonych warunkach, na stanowisku badawczym metodą...
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Szacowanie niepewności pomiarowej układu do diagnostyki łożysk opartej na analizie mocy chwilowej.
PublikacjaW artykule przedstawiono metodologię szacowania niepewności pomiarowej wykorzystanego do badań diagnostycznych łożysk silników indukcyjnych układu pomiarowego, składającego się z dzielnika napięcia oraz bocznika. Wyniki tych analiz pozwalają spre-cyzować, jakiej niepewności pomiarowej można się spodziewać, dokonując badań diagnostycznych łożysk silników indukcyjnych w określonych warunkach, na stanowisku badawczym metodą pomiaru...