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High precision and accuracy using low cost GNSS receivers and supporting technologies
PublikacjaThis chapter focuses on methods and techniques of positioning, based on the highly accurate and precise Global Navigation Satellite System (GNSS), which are available at a relatively low price. In this context, a comparison of different positioning methods provided by the free and open source software (FOSS) package called RTKLIB is given. Other aspects related to price reduction are also considered, including availability and...
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Application of Maximum-Length Sequences to impulse response measurement of hydroacoustic communications systems
PublikacjaThere is a growing interest in digital transmission of telemetry data on ultrasonic waves. The dependence of signal attenuation on squared frequency, specific to the hy-droacoustic systems, induces problems that do not exist in monochromatic, narrowband radio communications systems. For adapting the transmission parameters to current propagation conditions, a precise knowledge of instantaneous changes of channel performances is...
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Gendered entrepreneurship and its impact on firm innovativeness - a literature review.
PublikacjaEntrepreneurs gain a lot of attention in recent decades. Even if a precise definition of entrepreneur and entrepreneurship remains problematic, it is clear that there is a strong link between entrepreneurship and innovativeness, as well as between entrepreneur and innovation. In the current era of globalisation, the importance of innovations is as great as never before. And so is the importance of innovativeness determinants. Investigating...
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Evaluation Of Single Pole Auto-Reclosing Effectiveness With Nonlinear Secondary Arc Model
PublikacjaThe paper discusses two evaluation methods of single pole auto-reclosing process effectiveness in HV transmission lines. Secondary arc current and recovery voltage results obtained by load flow calculation are compared to the results obtained by the time domain simulations. Moreover, a non-linear secondary arc implementation is presented. The authors indicate, that precise representation of secondary electric arc leads to more...
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Error analysis of calculating average d-q current components using Regular Sampling and Park transformation in FOC drives
PublikacjaIn electric drives using voltage source inverters, motor currents contain ripple component resulting from pulse-width modulated (PWM) voltage. The frequency range of the ripples is much higher than the bandwidth of current control. Therefore the control is performed on the basis of a fundamental current component, i.e. average value with the averaging time being the PWM period. In majority of cases the average current is measured...
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Cathodic Protection System of the Spiral Classifier at the KGHM Polska Miedź S.A. Ore Concentration Plant—Case Study of Commissioning and Control of Operating Parameters
PublikacjaThe project involved designing, constructing and commissioning a cathodic protection system for a selected spiral classifier operating at the KGHM Polska Miedź S.A. Ore Concentration Plant (O/ZWR). The authors developed a concept and assumptions regarding the corrosion protection of a large industrial device using a cathodic protection system with an external power source. Pre-project studies included conducting a trial polarization...
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Ochrona powietrza - europejskie standardy
PublikacjaCurrent regulations in EU oblige every member country to cover the protection of the air as well as determine, in a bright and clear way, the responsibilities of the governments to monitor the condition and introduce ways of protection of the air from pollution. If the responsibilities imposed by the directive on evaluation and management of the air quality are obeyed by the respective organs of member countries of EU, then the...
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Secondary arc modelling for single pole reclosing analyses
PublikacjaThe paper discusses two evaluation methods of single pole auto-reclosing process effectiveness in HV transmission lines. Secondary arc current and recovery voltage calculation results obtained by load flow calculation are compared to the results obtained by the time domain simulations. Moreover, a nonlinear secondary arc model implementation is presented. The paper presents the study results for the three types of EHV transmission...
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Development of an Advanced Control Algorithm for DAB DC/DC Converters: Inrush Current Limitation and Enhanced Operation in Transient States.
PublikacjaThe publication addresses the dynamic state challenges encountered during development of a dual active bridge (DAB) converter within DC microgrid systems. The conventional startup method is identified as instigating a cascade of unfavorable outcomes, encompassing elevated starting current, transformer current asymmetry, DC voltage distortions, EMI and heightened thermal stress on semiconductor components. Additionally, it necessitates...
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The Conceptual Research over Low-Switching Modulation Strategy for Matrix Converters with the Coupled Reactors
PublikacjaIn this paper, different Pulse Width Modulation (PWM) strategies for operating with a low-switching frequency, a topology that combines Conventional Matrix Converters (CMCs), and Coupled Reactors (CRs) are presented and discussed. The principles of the proposed strategies are first discussed by a conceptual analysis and later validated by simulation. The paper shows how the combination of CMCs and CRs could be of special interest...
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Monitoring of a historic sacral building on an example Basilica St. Nicholas in Gdańsk
Publikacjahe paper describes the case of monitoring the technical condition of a historic sacral building after a failure and during renovation works. In order to monitor the condition of the building, safely conduct diagnostic work, identify the causes of failures andsafely carry out renovation works, a detailed Facility Monitoring Program has been developed, which has been implemented, is operational and is a source of valuable data used...
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Coastal zone monitoring using Sentinel-1 SAR polarymetry data
PublikacjaIn recent years the role of the surveillance and security of Polish boundaries has significantly increased. Polish coastal zone monitoring requires various approaches using various technological means in order to ensure the protection of Polish boundaries. In this paper, the authors discuss and present alternatives to underwater surveillance methods of coastal area analysis and monitoring using data retrieved from the newly developed...
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Multi-agent large-scale parallel crowd simulation
PublikacjaThis paper presents design, implementation and performance results of a new modular, parallel, agent-based and large scale crowd simulation environment. A parallel application, implemented with C and MPI, was implemented and run in this parallel environment for simulation and visualization of an evacuation scenario at Gdansk University of Technology, Poland and further in the area of districts of Gdansk. The application uses a...
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Analysis of thoracic regional impedance changes using PCA approach
PublikacjaA multichannel impedance and one lead electrocardiographic recording system has been developed. The impedance measurement unit is built using a four-electrode technique. It consists of a sinusoidal, 40 kHz, current source and five measurement channels. Circumferential current electrodes have been located at a neck and an abdomen. Voltagemeasurement disk electrodes formed five two-electrode measurement ports. The impedance change...
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ENERGY STORAGE IN COMPRESSED AIR – SOLUTION SUPPORTING RENEWABLE ENERGY SOURCES
PublikacjaThis article presents a brief description of a power system, the current national power system daily load, the use of wind power as a renewable energy source and its share in the national load. It also discusses the methods for storing energy, their characteristics and possible solutions. The power storage and generation solution proposed in the article is based on the collaboration between a gas turbine and an air storage system....
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Przekształtniki tranzystorowe działające w trybie prądu trójkątnego
PublikacjaPrzekształtniki oparte na węgliku krzemu mogą być analizowane jako źródła napięcia lub prądu niezależnie od topologii przy odpowiednich parametrach filtru wyjściowego. Szczególnie interesujące są falowniki napięcia działające w trybie prądu trójkątnego. W referacie przedstawiono sterowanie trójfazowym falownikiem napięcia posiadającym właściwości źródła prądu. Pokazano, jak dobrać parametry filtru wyjściowego falownika. Oceniono...
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The use of plate springs for preloading of a system of tapered roller bearings of a wind turbine gearbox
PublikacjaThe use of preloaded tapered roller bearings in wind turbine drive systems allows a transfer of load in the case of high variations of axial forces. The examined bearing system, a modification of a current design, consists of a pair of different sized bearings. Previous study showed the high sensitivity of tapered roller bearings on the existing radial interference. Dimensional tolerances used in the original design do not allow...
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Impact of digital signal processing on FOC current feedback in high-speed PMSM drive
PublikacjaIn applications where size and weight of the electric motor are among major design concerns, Permanent Magnet Synchronous Motors (PMSMs) with wide operational speed-range are commonly preferred. Due to limited inverter switching frequency, high-speed operation of a drive results in a low ratio between the switching frequency and the fundamental frequency of motor voltage. Such operating conditions have been recently identified...
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Wybrane metody diagnostyki łożysk silników indukcyjnych oparte o pomiar prądu
PublikacjaW artykule zawarto przegląd wybranych metod diagnostyki łożysk silnika indukcyjnego, bazujących na pomiarach prądu zasilającego. Jedno z nowych rozwiązań przetwarzania sygnałów zostało zaadaptowane przez autorów do stosowanego przez nich systemu diagnostycznego. Wyniki wstępnych badań symulacyjnych zweryfikowanych badaniami na rzeczywistym obiekcie wskazują, że rozwiązanie to ułatwia diagnozowanie. Autorzy zamierzają prowadzić...
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Model and laboratory simulation of a induction motor for diagnostic purposes
PublikacjaStatistics say that bearings are this part of induction motors which is most susceptible to damage. The equipment employed for bearing diagnostics usually makes use of vibrations as the criterion for technical condition of the bearings. A faulty bearing results in additional motor vibrations. They are reflected in the harmonic content of stator currents. In certain operating conditions the current signal is the sole source of information...
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Analysis of AC/DC/DC Converter Modules for Direct Current Fast-Charging Applications
PublikacjaThe paper is a comprehensive laboratory comparison study of two galvanic isolated solution off-board battery chargers: (1) Si-based cost-effective case, and (2) SiC-bidirectional ready for vehicle to grid concept case. All circuits are modular, and in both cases the DC/DC converter can be replaced according to the end user requirements (the coupled transformer remains the same and is constructed based on 12xC100 cores to avoid...
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The effects of offshoring to low-wage countries on domestic wages: a worldwide industrial analysis
PublikacjaThis paper extends the literature on the implications of offshoring for labour markets by investigating its effect on the wages of different skill groups in a broad global context. The analysis draws on input–output data from the WIOD project, and in the panel analysed (13 manufacturing industries, 40 countries, 1995–2009) we account for up to 96 % of the international trade in manufacturing inputs. Being particularly interested...
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The Impact of Micro-Sources on Voltage Distortions in a Power Grid
PublikacjaThe increase in the number of photovoltaic (PV) systems integrated with low voltage (LV) grids has led to a great need to analyse the impact of these systems on the quality of electricity and the reliability of its supply. This paper presents and compares the energy quality requirements imposed by various countries on photovoltaic plants. Then, based on real object tests and simulation in DIgSILENT PowerFactory, the impact has...
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REVIEW OF CURRENT RESEARCH ON CHITOSAN AS A RAW MATERIAL IN THREE-DIMENSIONAL PRINTING TECHNOLOGY IN BIOMEDICAL APPLICATIONS
PublikacjaThree-dimensional (3D) biomaterial manufacturing strategies show an extraordinary driving force for the development of innovative solutions in the biomedical sector, including drug delivery systems, disease modelling and tissue and organ engineering. Due to its remarkable and promising biological and structural properties, chitosan has been widely studied for decades in several potential applications in the biomedical field. However,...
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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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On extending open source IMS platform for integrated IPTV and VoIP services over IPv6
PublikacjaEven when IMS is the most popular platform for multimedia services, the open versions of IMS ecosystem are lacking in specified functionalities for IPTVv6 and VoIPv6 services. In this paper, we extend current client and server open source software in order to provide reliability and security to these multimedia services. As a part of our work the IMS architecture for conferencing system with proposed mechanisms to improve system...
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Common-Mode Voltage and Bearing Currents in PWM Inverters: Causes, Effects and Prevention
PublikacjaIn modern induction motor drives an increase of transistors' switching frequency and a decrease of switching times are the sources of some serious problems. The high dv/dt and the common mode voltage generated by the inverter PWM control results in the appearances of bearing currents, shaft voltages, motor terminal overvoltages, the decrease of motor efficiency, and electromagnetic interference. The aspects of common mode (CM)...
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BADANIA SYMULACYJNE PROWADZONE W ŚRODOWISKU SYSTEMU EKSPERTOWEGO STOSOWANE DO WSPOMAGANIA PROJEKTOWANIA UKŁADÓW AUTOMATYKI STATKU
PublikacjaW referacie przedstawiono wykorzystanie badań symulacyjnych jako źródła wiedzy dla systemu ekspertowego. Omawiany system służy wspomaganiu doboru elementów steru strumieniowego. Elementami tego systemu są: biblioteka struktur, biblioteka modeli, baza elementów oraz baza wiedzy. Jako przykład przedstawiono badania symulacyjne struktury steru strumieniowego zawierającej silnik indukcyjny, wał śrubowy, śrubę o skoku nastawnym oraz...
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Managing Quality Contests Based on Excellence Model at the Local Level. Selected Conditions and Problems – Case Study
PublikacjaThe aim of this article was to present characteristic phenomena accompanying competitions for quality awards based on the use of the organizational excellence models implemented at the regional level. Typical problems were identified, the understanding of which allows for a better use of the idea of excellence to raise the overall level of maturity of organizations aspiring to quality awards at every level. The results of self-assessment...
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Cyanides in the environment—analysis—problems and challenges
PublikacjaCyanide toxicity and their environmental impact are well known. Nevertheless, they are still used in the mining, galvanic and chemical industries. As a result of industrial activities, cyanides are released in various forms to all elements of the environment. In a natural environment, cyanide exists as cyanogenic glycosides in plants seeds. Too much consumption can cause unpleasant side effects. However, environmental tobacco smoke...
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Electron mobility variance in semiconductors: the variance approach
PublikacjaPraca przedstawia nowe podejście da analizy zjawisk losowych w półprzewodnikach. Uwzględnia kilka mechanizmów zjawisk fluktuacji ruchliwości w półprzewodnikach, prowadzących do powstawamai składowej szumów typu 1/f, dominujących w zakresie małych czetotliwości. Przedstawia analizę sposobu wyznaczenia stałej Hooge'a określającej intensywność szumów typu 1/f.The statistical non-triviality of current carrier mobility fluctuations...
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Cannabinoids: Challenges, opportunities and current techniques towards its extraction and purification for edibles
PublikacjaDue to the multiple health benefits associated with the consumption of cannabinoids, there is a current trend on continuing to explore their biological properties. Cannabidiol (CBD) is likely to be the most investigated endocannabinoid from the cannabis plant. Unfortunately, the purification of CBD from its natural source and psychotropic analogue (tetrahydrocannabinol, THC) is timely challenging for the research community based...
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Controlling nodal displacement of pantographic structures using matrix condensation and interior-point optimization: A numerical and experimental study
PublikacjaThis study presents an innovative approach for the precise control of nodal displacements in pantographic structures. The method is founded on the Matrix Condensation of Force Method, seamlessly integrated with an Interior Point Optimization algorithm. This combination offers a unique advantage by allowing users to manipulate displaced nodes within a defined coordination domain. Furthermore, this approach introduces the Interior...
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Modeling the impact of discretizing rotor angular position on computation of field-oriented current components in high speed electric drives
PublikacjaModern drives consist of alternating current electric motors, and the field-oriented control (FOC) of such motors enables fast, precise, and robust regulation of a drive's mechanical variables such as torque, speed, and position. The control algorithm, implemented in a microprocessor, requires feedback from motor currents, and the quality of this feedback is essential to a drive's control properties. Motor phase currents are sampled...
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Sound intensity distribution around organ pipe
PublikacjaThe aim of the paper was to compare acoustic field around the open and stopped organ pipes. The wooden organ pipe was located in the anechoic chamber and activated with a constant air flow, produced by an external air-compressor. Thus, long-term steady state response was possible to obtain. Multichannel acoustic vector sensor was used to measure the sound intensity distribution of radiated acoustic energy. Measurements have been...
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Synteza bezczujnikowego sterowania maszyną indukcyjną klatkową zasilaną z falownika prądu
PublikacjaSynteza bezczujnikowego sterowania maszyną indukcyjną klatkową zasilaną z falownika prądu stanowi cel niniejszej monografii. Praca zawiera podstawowe informacje na temat modelowania układu napędowego z maszyną indukcyjną klatkową zasilaną z falownika prądu. Przedstawiono informacje na temat linearyzacji nieliniowych obiektów. Na pod-stawie metody syntezy strukturalnej opracowano nowe transformacje do postaci zmien-nych multiskalarnych,...
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Air journal bearing utilizing near-field acoustic levitation: stationary shaft case
PublikacjaResults of a study to examine a unique idea of self-levitating journal bearing are presented in this paper. the idea represents a radical departure from the current bearing technology. it utilisesacoustic levitation, which relies on the sound energy radiated by an object supporting a load. acoustic levitation has been demonstrated to support loads of up to 10 kg. in order to support a load theacoustic wave emitted by the radiating...
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Bioactive Ingredients with Health-Promoting Properties of Strawberry Fruit (Fragaria x ananassa Duchesne)
PublikacjaStrawberries (Fragaria x ananassa Duchesne) belong to the berry group and are characterized primarily by delightful sensory properties. Due to their chemical composition, these fruits are a rich source of bioactive compounds that can modify the metabolic and physiological functions of the body. The aim of this work is to present the current state of research on bioactive ingredients found in these fruits in the context of their...
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Latest Achievements in Concrete Structures Three-Dimensional Printing
PublikacjaWe can hear about three-dimensional printed concrete structures for several years, up to date solutions in this technology allow entire printing settlements of tiny concrete houses. Due to technical limitations, these houses are still small and not very durable, but undoubtedly, this technology is developing. Home printed in three-dimensional technology can be an alternative to modular container buildings implemented in areas affected...
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Determination of toxic gases based on the responses of a single electrocatalytic sensor and pattern recognition techniques
PublikacjaA response from an electrocatalytic gas sensor contains fingerprint information about the type of gas and its concentration. As a result, a single gas sensor can be used for the determination of different gases. However, information about the type of gas and its concentration is hidden in the unique shape of the current–voltage response and it is quite difficult to explore. One of the ways to get precise information about the measured...
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Sensing the onset of epoxy coating degradation with combined Raman spectroscopy/atomic force microscopy/electrochemical impedance spectroscopy
PublikacjaThe paper presents the results of investigation on epoxy resin durability upon 12-week exposure to UV radiation. The aim was early determination of the onset of epoxy degradation and for this purpose an epoxy film on steel substrate systems were periodically inspected using Raman spectroscopy, atomic force microscopy and electrochemical impedance spectroscopy. The behaviour of examined polymer could be divided into three periods: immunity,...
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An application of acoustic sensors for the monitoring of road traffic
PublikacjaAssessment of road traffic parameters for the developed intelligent speed limit setting decision system constitutes the subject addressed in the paper. Current traffic conditions providing vital data source for the calculation of the locally fitted speed limits are assessed employing an economical embedded platform placed at the roadside. The use of the developed platform employing a low-powered processing unit with a set of microphones,...
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Using LSTM networks to predict engine condition on large scale data processing framework
PublikacjaAs the Internet of Things technology is developing rapidly, companies have an ability to observe the health of engine components and constructed systems through collecting signals from sensors. According to output of IoT sensors, companies can build systems to predict the conditions of components. Practically the components are required to be maintained or replaced before the end of life in performing their assigned task. Predicting...
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Effects of La0.8Sr0.2MnO3 and Ag electrodes on bismuth-oxide-based low-temperature solid electrolyte oxygen generators
PublikacjaIn this study, La0.8Sr0.2MnO3 (LSM) was used as the ceramic electrode in a (Bi1.50Y0.50)0.98Zr0.04O3+δ (BYO)-based solid electrolyte oxygen generator (SEOG) and its performance was compared with that of a previously studied high-fire Ag electrode. Among La0.6Sr0.4Co0.2Fe0.8O3, LaNi0.6Fe0.4O3, Cu1.4Mn1.6O4, and LSM materials, only LSM materials did not trigger any chemical reaction or interdiffusion with BYO at temperatures up to...
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Spinning Fluids Reactor: A new design of a gas – liquid contactor
PublikacjaCurrent trends in chemical reactor design are based on adapting these to the requirements of a particular chemical process. Processes involving reactions between the gas and liquid phase in particular require precise adjustment of all parameters. The common denominator for most modern design solutions is enhancement of the mass transfer area and the overall volumetric mass transfer coefficient. Gas – liquid contactors evolved from...
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Fabrication of high-density nitrogen-vacancy (NV) center-enriched diamond particles through methyl trityl amine (C20H19N) seeding
PublikacjaDiamond particles (DPs) show promise for advanced applications in bioimaging and quantum sensing due to the presence of defect centers. This work reports a unique growth process for diamond particles composed of nitrogen-vacancy centers (NV-DPs) using a methyl trityl amine (C20H19N) diamondoid seed, which acts as a nitrogen source for NV creation. Growth was performed via microwave plasma-assisted chemical vapor deposition in a...
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Dead-Time Effect Compensation Based on Additional Phase Current Measurements
PublikacjaThis paper proposes a new method of dead-time effect compensation. The proposed solution is based on additional phase current measurements realized by analog-to-digital converters. These measurements are carried out at the time instants specified by a pulsewidth-modulation (PWM) strategy. This makes it possible to estimate inverter currents at the commutation instants and, finally, to estimate the voltage error caused by dead time. This...
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Regional quality contests based on business excellence models – Pomeranian case study
PublikacjaCompetitions based on models of organizational excellence have significant potential. Organizations participating in these initiatives have the chance not only to get marketing benefits, but also gain comprehensive knowledge about their management systems. Moreover, thanks to the structure of models of excellence an organization can plan in detail the improvement activities in its main processes. The aim of the authors is to analyze...
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Extraction pathways and purification strategies towards carminic acid as natural-based food colorant: A comprehensive review
PublikacjaAs a current trend of fabricating healthier products, food manufacturing companies seek for natural-based food colorant aiming to replace the synthetic ones, which apart from meeting sensorial and organoleptic aspects, they can also act as health promoters offering additional added value. Carminic acid is a natural based food colorant typically found in several insect taxa. However, there are current approaches which pursue the...
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Experimental and theoretical study of a vertical tube in shell storage unit with biodegradable PCM for low temperature thermal energy storage applications
PublikacjaThis article presents the experimental investigations of the coconut oil-based TES module for HVAC applications in the ambient and-sub ambient temperature range. To properly study this problem modular experimental module and test loop were developed. Special attention has been paid to study the physical mechanism of the melting/solidification process for natural substance (coconut oil) which has perspectives to be used in thermal...