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Rapid Re-Design and Bandwidth/Size Trade-Offs for Compact Wideband Circular Polarization Antennas Using Inverse Surrogates and Fast EM-Based Parameter Tuning
PublicationDesign of compact wideband circularly polarized (CP) antennas is challenging due to the necessity of simultaneous handling of several characteristics (reflection, axial ratio, gain) while maintaining a small size of the structure. Antenna re-design for various operating bands is clearly more difficult yet practically important because intentional reduction of the bandwidth (e.g., by moving the lower edge of the operating band up...
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New analytical sample preparation techniques in food flavour analysis
PublicationIn this chapter sample preparation techniques were broadly characterized and their applications in field of food analysis were presented. Usefulness of three extraction methods: SPME, SAFE and SDE for isolation of aroma compounds from complex food matrices was compared. Additionally, requirements for sample preparation methods using in food flavour analysis were detailed.
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Accelerometer-based Human Activity Recognition and the Impact of the Sample Size
PublicationThe presented study focused on the recognition of eight user activities (e.g. walking, lying, climbing stairs) basing on the measurements from an accelerometer embedded in a mobile device. It is assumed that the device is carried in a specific location of the user’s clothing. Three types of classifiers were tested on different sizes of the samples. The influence of the time window (the duration of a single trial) on selected activities...
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Applications of sample preparation techniques in the analysis of pesticides and PCBS in food
PublicationPestycydy oraz anality z grupy polichlorowanych bifenyli (PCB), można znaleźć w żywności w niewielkich stężeniach, jednak ich zdolność do kumulacji i toksyczność powodują konieczność oznaczanie tych związków w żywności. Analiza próbek żywności pod kątem obecności pestycydów i analitów z grupy PCB przysparza wiele trudności ze względu na specyfikę przygotowania próbki w oparciu o wieloetapowe operacje oczyszczania próbki zawierającej...
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Tetrapod trackways from the early Middle Devonian period of Poland
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Applications of Graphene-based Materials in Chromatography and Sample Preparation: A Review
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Development and validation of the attitude towards Surrogacy Scale in a polish sample
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Adaptation of the Four Forms of Employee Silence Scale in a Polish sample
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Thermally stimulated carrier transport due to stepwise sample heating.
PublicationPodano przybliżone rozwiązania równań nieizotermicznego transportu nośników w izolującym ciele stałym ze stanami pułapkowymi, dla przypadku krokowego ogrzewania próbki. Otrzymane wyniki zweryfikowano za pomocą symulacji Monte Carlo dla gaussowskiego rozkładu pułapek.
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Sample preparation and chromatographic analysis of acidic herbicides in soils and sediments
PublicationW pracy przedstawiono różne techniki przygotowania próbek i oznaczania herbicydów z grupy pochodnych fenoli i pochodnych kwasów karboksylowych w próbkach gleby. Opisano wybrane metody wzbogacania i izolacji analitów, m. in.: ekstrakcję za pomocą wodnych roztworów zasad i rozpuszczalników organicznych płynem w stanie nadkrytycznym, wodą w stanie podkrytycznym, cieczą pod zwiększonym ciśnieniem, cieczą wspomaganą mikrofalami. Niski...
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Surfactants application in sample preparation techniques: Insights, trends, and perspectives
PublicationSince the implementation of Green Chemistry into analytical practice, significant efforts have been made to improve the sustainability of chemical analysis. These include reducing the use of hazardous chemicals and solvents, minimizing waste, and improving energy efficiency. Surfactants can be applied in chemical analysis as an environmentally friendly alternative to conventional solvents and chemicals. The use of surfactants can...
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On Sample Rate Conversion Based on Variable Fractional Delay Filters
PublicationThe sample rate conversion algorithm based on variable fractional delay filters is often used if the resampling ratio cannot be expressed as the ratio of small integer numbers or if it is not constant. The main advantage of such solution is that it allows for arbitrary resampling ratios which can even be changed during the resampling process. In this paper a discussion on influence of different approaches to fractional filter...
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Sample preparation techniques for determination of pesticide residues in food samples
PublicationPesticides are very important in increasing the efficiency and quality of agricultural production. They are applied in many spheres of life, not only in agriculture, and their applications are expanding. Despite their numerous merits, pesticides are some of the most toxic substances contaminating our environment and have a negative impact on the human health. Properties of pesticides such as stability, ability to bioaccumulation...
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Progress in development of molecularly imprinted polymers as sorbents for sample preparation
PublicationSample preparation has been one of the most often investigated steps in analytical procedures.These investigations are focused on problems such as isolation of analytes from the sample matrix, matrix implification, analyte enrichment to the level above the detection limit of the instrumentation used, and the removal of interfering species to improve the final determination. Techniques based on solid (adsorption) and pseudo liquid...
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Sample preparation and recent trends in volatolomics for diagnosing gastrointestinal diseases
PublicationThe analysis of the human volatilome can be successfully used for rapid and non-invasive diagnostics of gastrointestinal diseases. However, the introduction of techniques based on detection of volatiles is limited, among other factors, by difficulties which arise during the sampling stage and instrumental analysis. The aim of this article was to review and discuss medical and analytical literature on the analysis of volatiles in...
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Chemical identification of rubber fender sample and hardness and density measurements
PublicationScope of testing: Chemical identification of rubber fender sample and hardness and density measurements. - Raport z badań zleconych - Numer umowy: 031178
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Preliminary study on icebreaking operation on the Middle and Lower Odra River
PublicationThe Odra-Vistula Flood Management Project (OVFMP) is implemented with the assistance of international financial institutions, including the International Bank for Reconstruction and Development and the Council of Europe Development Bank, as well as with the support of funding from the Cohesion Fund and the state budget. Aside from others, the objective of the OVFMP is to increase flood protection for people living in selected areas...
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Sample Rate Conversion Based on Frequency Response Masking Filter
PublicationThe sample rate conversion with high resampling ratios requires low-pass digital filters with very narrow transition band which results in high computational complexity and makes filter design problematic. Therefore in this work we propose to use the FRM method, which breaks the filter with a narrow transition band into a group of filters with reduced design requirements. These decreases the number of non-zero coefficients and...
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Arginine-, d-arginine-vasopressin, and their inverso analogues in micellar and liposomic models of cell membrane: CD, NMR, and molecular dynamics studies
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Boundary value problems with advanced arguments involving upper and lower solutions in reverse order
PublicationPraca dotyczy problemów brzegowych dla równań różniczkowo-całkowych pierwszego rzędu z argumentami wyprzedzonymi. Podano wystarczające warunki, dla których problemy dotyczące takich równań mają rozwiązania minimalne i maksymalne w odpowiadającym obszarze ograniczonym przez rozwiązania górne i dolne. W celu uzyskania wyników zastosowano nową metodę opartą na twierdzeniu Heikkila-Lakshmikantham'a. Wyniki zilustrowano na przykładzie.
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The Application of Cellulose Acetate Membranes for Separation of Fermentation Broths by the Reverse Osmosis: A Feasibility Study
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Hybrid Obfuscation Technique to Protect Source Code From Prohibited Software Reverse Engineering
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On the estimation of the design loads on container stacks due to excessive acceleration in adverse weather conditions
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Shaping the SPL Spectra of the Acoustic Noise Emitted by Inverter-Fed Indu- ction Motors
PublicationW artykule przedstawiono nowe podejście do zmniejszania wpływu właściwości mechanicznych maszyny na emitowany przez nią hałas akustyczny. Dokonano identyfikacji mechanicznych rezonansów maszyny wykorzystując modulację RPWM z losowym wyborem częstotliwości nośnej oraz modulację sigma delta, dla której otrzymano relatywnie płaskie widmo prądu. Skonstruowano na tej podstawie funkcję gęstości prawdopodobieństwa wyboru częstotliwości...
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Dead time effects compensation strategy by third harmonic injection for a five-phase inverter
PublicationThis paper proposes a method for compensation of dead-time effects for a fivephase inverter. In the proposed method an additional control subsystem was added to the field-oriented control (FOC) scheme in the coordinate system mapped to the third harmonic. The additional control loop operates in the fixed, orthogonal reference frame ( α - β coordinates) without the need for additional Park transformations. The purpose of this method...
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Application of persulfate-based oxidation processes to address diverse sustainability challenges: A critical review
PublicationOver the past years, persulfate (PS) is widely applied due to their high versatility and efficacy in decontamination and sterilization. While treatment of organic chemicals, remediation of soil and groundwater, sludge treatment, disinfection on pathogen microorganisms have been covered by most published reviews, there are no comprehensive and specific reviews on its application to address diverse sustainability challenges, including...
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Sensorless control system of induction machine supplied by voltage source inverter with output filter
PublicationThe paper focuses on sensorless control of the induction machines supplied by inverter with the output filters. “The novel” idea of the speed observer which is based on the backstepping approach is shown. The standard structure of the exponential observer is extended by the integrators and additional Z vector. The simulation and experimental results validate the proposed solution.
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The adaptive backstepping control of PMSM supplied by current source inverter for the field weakening region
PublicationThe sensorless control system of permanent magnet synchronous motor PMSM supplied by current source inverter for field weakening operation is presented in this paper. The adaptive backstepping control system and the backstepping speed observer are presented. The control system is based on multi-scalar variables. The control variables are: dc-link voltage and the output current vector pulsation. The control system was named voltage...
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Multilevel inverter neutral-point voltage sensor diagnostic based on the Extended Kalman Filter
PublicationA new algorithm for neutral point voltage imbalance estimation in DC link of the three-level (3L) neutral point clamped (NPC) voltage source inverter (VSI) is proposed. Application of the proposed algorithm does not require any additional sensors. The unbalanced voltage calculation is based on the information derived from the inverter output measured currents and from the knowledge of the load model parameters. In order to estimate...
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Geographic information system for remote integration of diverse under-water acoustic sensor data
PublicationMaritime and port areas throughout the world are exposed to many different hazards, like pollution, terrorism and natural disasters. Early detection, identification and preparation of appropriateesponse strategies is especially important in the case of semi-enclosed basins like the Baltic Sea, mainly due to the marine ecosystems' continuous absorption of pollutants including oil, heavy metals and chemicals. Many of those agents...
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The Adaptive Backstepping Control of Permanent Magnet Synchronous Motor Supplied by Current Source Inverter
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Errors in the analysis of series resonant inverter/converter assuming sinusoidal waveforms of voltage and current
PublicationIn this paper the theory and simulation results of the series resonant inverter / converter are presented. In this work the authors carried out a detailed comparative analysis of results obtained using the method of AC analysis in the steady state for the first harmonic with the results of computer simulation. The AC analysis under certain conditions can lead to errors disqualifying this method. In particular, these errors appear...
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MPPT and GMPPT Implementation for Buck-Boost Mode Control of quasi-Z-Source Inverter
PublicationThe focus is on the maximum power point tracking implementation for the buck-boost voltage mode control of a single-phase multilevel inverter based on a three-level neutral point clamped quasi-Z-source topology. To utilize shoot-through states only when boost function is needed and avoid it in the buck mode, two different control approaches are required. This work proposes merged control system which provides switching between...
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Optimizing FSO networks resilient to adverse weather conditions by means of enhanced uncertainty sets
PublicationThis work deals with dimensioning of wireless mesh networks (WMN) composed of FSO (free space optics) links. Although FSO links realize broadband transmission at low cost, their drawback is sensitivity to adverse weather conditions causing transmission degradation on multiple links. Hence, designing such FSO networks requires an optimization model to find the cheapest configuration of link capacities that will be able to carry...
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Trimethylamine N-oxide and the reverse cholesterol transport in cardiovascular disease: a cross-sectional study
PublicationThe early atherosclerotic lesions develop by the accumulation of arterial foam cells derived mainly from cholesterol-loaded macrophages. Therefore, cholesterol and cholesteryl ester transfer protein (CETP) have been considered as causative in atherosclerosis. Moreover, recent studies indicate the role of trimethylamine N-oxide (TMAO) in development of cardiovascular disease (CVD). The current study aimed to investigate the association...
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Unidirectional DC/DC Converter with Voltage Inverter for Fast Charging of Electric Vehicle Batteries
PublicationThe paper proposes the adaptation of the industrial plant’s power network to supply electric vehicle (EV) fast-charging converters (above 300 kW) using renewable energy sources (RESs). A 600 V DC microgrid was used to supply energy from RESs for the needs of variable speed motor drives and charging of EV batteries. It has been shown that it is possible to support the supply of drive voltage frequency converters (VFCs) and charging...
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Reducing common mode voltage and bearing currents in quasi - resonant DC - link inverter
PublicationIn the paper, a concept of separation of an inverter-fed induction motor drive from its mains supply by two transistor switches inserted in the dc-link circuit is reexamined based on the proposed parallel quasi-resonant dc-link inverter (PQRDCLI). The objective of the paper is to show an advantage of the proposed topology in limiting high frequency common mode voltage and bearing currents. In the laboratory setup, an induction...
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Quasi-resonant DC-link voltage inverter with enhanced zero-voltage switching control
PublicationA new topology modification of the parallel quasi-resonant circuit for a dc-link voltage inverter enables regulation of the zero voltage dc-link subperiods and the dc-link voltage gradient settings. The proposed circuit is based on four MOSFET switches with free-wheeling diodes for controlled quasi-resonant recharging between L-C tank in order to assure inverter zero voltage switching (ZVS) conditions. Design optimization of the...
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Hybridized Space-Vector Pulsewidth Modulation for Multiphase Two-Level Voltage Source Inverter
PublicationIn space vector pulsewidth modulation (SVPWM) algorithms for multiphase two-level voltage source inverters (VSI), the components of active vectors in all orthogonal spaces have to be calculated within the processor and stored in its memory. These necessitate intensive computational efforts of the processor and large memory space. This article presents a hybridized SVPWM for multiphase two-level VSI. In this algorithm, elements...
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Ciencia & Saude Coletiva
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Adolescencia e Saude
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Mundo da Saude
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Saude e Sociedade
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Digest of Middle East Studies
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Middle East Journal of Cancer
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Middle East Law and Governance
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Journal of the Middle East and Africa
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Middle East Development Journal
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Middle East Journal of Anesthesiology
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Review of Middle East Studies
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