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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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Implementation of spatial/polarization diversity for improved-performance circularly polarized multiple-input-multiple-output ultra-wideband antenna
PublikacjaIn this paper, spatial and polarization diversities are simultaneously implemented in an ultra-wideband (UWB) multiple-input-multiple-output (MIMO) antenna to reduce the correlation between the parallel-placed radiators. The keystone of the antenna is systematically modified coplanar ground planes that enable excitation of circular polarization (CP). To realize one sense of circular polarization as well as ultra-wideband operation,...
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Interdisciplinary e-collaboration tools / Narzędzia interdyscyplinarnej e-współpracy
PublikacjaW projektach interdyscyplinarnych niezwykle ważnym czynnikiem jest aktywne konsultowanie i bezpośrednie zastosowanie relatywnie nowo powstałej dziedziny zwanej współpracą interdyscyplinarną. Nawiązywanie interdyscyplinarnej współpracy przynosi wiele korzyści, jednakże niejednokrotnie wiąże się z licznymi problemami i niedogodnościami, a także koniecznością ciągłego doszkalania się i rozszerzania kompetencji zawodowych. Na podstawie...
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Thermoplastic elastomer filaments and their application In 3D printig
PublikacjaThe paper provides an overview on the materials used in the 3D printing technology (the Polish and foreign market) with a particular focus on flexible filaments and their possible application in the industry. There are described the techniques of 3D printing and modern filaments available on the market. There is observed the increase of interest in the production of products from filaments based on thermoplastic elastomers (TPE),...
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Application of analytical methods for the determination of bioactive compounds in some berries
PublikacjaFluorometry, ESI-MS, FTIR, and radical scavenging assays were used for characterization of bioactive compounds and the levels of their antioxidant activities. Polyphenols, flavonoids, anthocyanins, and ascorbic acid and the level of antioxidant activity of water extracts of “Murtilla-like” [Myrteola nummularia (Poiret) Berg.], and other widely consumed berries were determined and compared. The contents of bioactive compounds and...
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LABORATORIUM SZYBKIEGO PROTOTYPOWANIA : Inżynieria odwrotna
PublikacjaSzybkie prototypowanie (ang. Rapid Prototyping) i inżynieria odwrotna (ang. Reverse Engineering) są jednymi z najbardziej dynamicznie rozwijających się działów komputerowego wspomagania projektowania, wytwarzania i realizacji prac inżynierskich (CAD/CAM/CAE). Inżynieria odwrotna stanowi zwykle wyjściowy etap szybkiego prototypowania. Udostępnia ona metody generowania wirtualnych modeli 3D istniejących obiektów w wyniku ich pomiarów....
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Multi-objective optimization of expensive electromagnetic simulation models
PublikacjaVast majority of practical engineering design problems require simultaneous handling of several criteria. For the sake of simplicity and through a priori preference articulation one can turn many design tasks into single-objective problems that can be handled using conventional numerical optimization routines. However, in some situations, acquiring comprehensive knowledge about the system at hand, in particular, about possible...
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Optymalizacja postaci konstrukcyjnej dynamometru-uchwytu próbek badanych wwarunkach mikrooscylacji. W: [CD-ROM] III Konferencja Naukowo-Techniczna SYMULACJA 2002. Wdzydze Kiszewskie, 16 - 18 październik 2002. Tarnowskie Góry: MESco**2002 [16 s. 19 rys. bibliogr. 9 poz.]
PublikacjaW ramach badań tribologicznych prowadzonych w Katedrze Konstrukcji i Eksplo-atacji Maszyn Politechniki Gdańskiej zaprojektowano i skonstruowano stanowi-sko z głowicą SOOG do wyznaczenia odporności materiałów ślizgowych na zuży-cie w warunkach mikroprze-mieszczeń w płaszczyźnie ślizgania. Specyfika sta-nu obciążenia próbek z badanych materiałów, wymagała zastosowania wielu ory-ginalnych rozwiązań konstrukcyjnych. Do głównych...
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The Effect of Steaming Beech, Birch and Maple Woods on Qualitative Indicators of the Surface
PublikacjaThis work presents the effect of steaming beech, birch and maple woods on the resulting quality of the milled wood surface. The steaming process of the studied woods results in a targeted change in the color of the wood, which changes from the original light white-gray color to fine reddishbrown to dark brown color shades that are more or less saturated depending on the temperature of the saturated water steam. The color changes...
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Dual-Activity Fluoroquinolone-Transportan 10 Conjugates offer alternative Leukemia therapy during Hematopoietic Cell Transplantation
PublikacjaHematopoietic cell transplantation (HCT) is often considered a last resort leukemia treatment, fraught with limited success due to microbial infections, a leading cause of mortality in leukemia patients. To address this critical issue, we explored a novel approach by synthesizing antileukemic agents containing antibacterial substances. This innovative strategy involves conjugating fluoroquinolone antibiotics, such as ciprofloxacin...
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Smart Decisional DNA Technology to Enhance Industry 4.0 Environment in Conjunction with Conventional Manufacturing
PublikacjaKnowledge-based support has become an indispensable part not only to the traditional manufacturing set-ups but also to the new fast-emerging Industry 4.0 scenario. In this regard, successful research has been performed and extensively reported to develop Decisional DNA based knowledge representation models of engineering object and engineering process called Virtual engineering object (VEO), Virtual engineering process (VEP) and...
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Highly crystalline colloidal nickel oxide hole transport layer for low-temperature processable perovskite solar cell
PublikacjaHighly crystalline NiOX usually requires high annealing temperature (>300 °C) which is incompatible with flexible substrate and might consume high amount of energy. Herein, we demonstrate a facile emulsion process to synthesize highly crystalline, low temperature deposition (<150 °C) and solution processable NiOx nanoparticles (NPs) as a hole transport layer for the perovskite solar cells (PVSCs). A novel surfactant of tetramethylammonium...
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Comparison of Renewable Energy Sources in ‘New’ EU Member States in the Context of National Energy Transformations
PublikacjaThe European Union strives to create sustainable, low-carbon economies; therefore, energy policies of all member states should move towards renewable energy sources (RES). That concerns also the so-called new EU member states. These countries, on the one hand, are characterized by significant historical similarities in terms of post-communist legacy and adopted development strategies linked with the EU membership, and on the other...
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Rapid tolerance‐aware design of miniaturized microwave passives by means of confined‐domain surrogates
PublikacjaThe effects of uncertainties, primarily manufacturing tolerances but also incomplete information about operating conditions or material parameters, can be detrimental to the performance of microwave components. Quantification of such effects is essential to ensure a meaningful evaluation of the structure, in particular, its reliability under imperfect fabrication procedures. The improvement of the circuit robustness can be achieved...
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Low-cost performance-driven modelling of compact microwave components with two-layer surrogates and gradient kriging
PublikacjaUtilization of electromagnetic (EM) simulation tools has become indispensable for reliable evaluation of microwave components. As the cost of an individual analysis may already be considerable, the computational overhead associated with EM-driven tasks that require massive simulations (e.g., optimization) may turn prohibitive. One of mitigation methods is the employment of equivalent network models. Yet, they are incapable of accounting...
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Effect of the integration into Global Value Chains on the employment contract in Central and Eastern European countries
PublikacjaResearch background: In the era of globalization, there is a need to address decent work deficits in Global Value Chains (GVCs). The forms of working conditions reveal a broad dispersion of contents. The literature review exposes hardly any Europe-focused research assessing the socioeconomic impact of global production links and going beyond their pure economic effects assessed in terms of employment, productivity or wages. Purpose...
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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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Knowledge Sharing in the COVID-19 Era of Remote Teaching: What Can Academia Learn from Business?
PublikacjaPurpose: The aim of this paper is to investigate how universities may benefit from experiences of businesses that were also forced to use remote forms of business operations. Methodology: The paper uses in-depth interviews to explore the possibilities of knowledge sharing improvements at the university-level teaching, based on the experiences elicited in the business sector. The theoretical sampling was used to find informants...
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Generalized Formulation of Response Features for Reliable Optimization of Antenna Input Characteristics
PublikacjaElectromagnetic (EM)-driven parameter adjustment has become imperative in the design of modern antennas. It is necessary because the initial designs rendered through topology evolution, parameter sweeping, or theoretical models, are often of poor quality and need to be improved to satisfy stringent performance requirements. Given multiple objectives, constraints, and a typically large number of geometry parameters, the design closure...
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Multiple Cues-Based Robust Visual Object Tracking Method
PublikacjaVisual object tracking is still considered a challenging task in computer vision research society. The object of interest undergoes significant appearance changes because of illumination variation, deformation, motion blur, background clutter, and occlusion. Kernelized correlation filter- (KCF) based tracking schemes have shown good performance in recent years. The accuracy and robustness of these trackers can be further enhanced...
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On Improved-Reliability Design Optimization of High-Frequency Structures Using Local Search Algorithms
PublikacjaThe role of numerical optimization has been continuously growing in the design of high-frequency structures, including microwave and antenna components. At the same time, accurate evaluation of electrical characteristics necessitates full-wave electromagnetic (EM) analysis, which is CPU intensive, especially for complex systems. As rigorous optimization routines involve repetitive EM simulations, the associated cost may be significant....
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Enhanced-Performance Circularly Polarized MIMO Antenna with Polarization/Pattern Diversity
PublikacjaDesign of a compact wideband circularly polarized (CP) multiple-input multiple-output (MIMO) antenna with polarization diversity is proposed and characterized for off-body communication. The antenna is based on a simple coplanar waveguide (CPW)-fed monopole extension of the microstrip line. The orthogonal field components required by CP are induced using a simply modified right/left side ground plane. In particular, a stub extending...
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ANALIZA AERODYNAMICZNA ŁOPAT NA PRZYKŁADZIE PROJEKTU DWUWIRNIKOWEJ TURBINY WIATROWEJ MAŁEJ MOCY
PublikacjaW artykule przedstawiono proces projektowania oraz analizy aerodynamicznej łopat turbiny wiatrowej z wykorzystaniem metody BEMT (ang. Blade Element Momentum Theory). Dokonano doboru profili aerodynamicznych oraz opisano procedurę wyznaczania optymalnego rozkładu kątów zwichrowania i długości cięciw profili w funkcji długości łopaty dla założonych parametrów wejściowych. Dokonano obliczenia działających sił oraz generowanej mocy...
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Towards Hybrid Urban Mobility: Kick Scooter as a Means of Individual Transport in the City
PublikacjaThe characteristic feature of a contemporary city is its inconvenience and oppressiveness caused by the hitherto dominant paradigm of urban planning based on car mobility. As a result, the inhabitants have to cope with air pollution, noise, spatial barriers, sedentary lifestyle and other factors which worsen their health and quality of life. Ecological and physically activating urban mobility thus plays an increasingly important...
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DATABASE AND BIGDATA PROCESSING SYSTEM FOR ANALYSIS OF AIS MESSAGES IN THE NETBALTIC RESEARCH PROJECT
PublikacjaA specialized database and a software tool for graphical and numerical presentation of maritime measurement results has been designed and implemented as part of the research conducted under the netBaltic project (Internet over the Baltic Sea – the implementation of a multi-system, self-organizing broadband communications network over the sea for enhancing navigation safety through the development of e-navigation services.) The...
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The thermostability, bioactive compounds and antioxidant activity of some vegetables subjected to different durations of boiling: investigation in vitro
PublikacjaThis research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of theirbioactive compounds, antioxidant activity and thermostability.It was found that polyphenols (mg GAE/g), flavanols (mg GAE/g), flavonoids (mg CE/g), anthocyanins (mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots...
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Studies on removal of Zn(II), Cd(II) and Pb(II) ions in polymer inclusion membrane transport with calix[4]-crown-6 derivatives
PublikacjaZbadano selektywność procesu wydzielania jonów cynku(II), kadmu(II) i ołowiu(II) z wodnych roztworów azotanowych zawierających równomolową mieszaninę tych trzech metali (cMe= 0,01 M) w procesie transportu przez polimerowe membrany inkluzyjne (PIM) przy użyciu w roli przenośników jonów pochodnych kaliks[4]-korony-6. Membrany typu PIM syntezowano z trójoctanu celulozy (nośnik), eteru o?nitrofenylopentylowego (pastyfikator) i pochodnych...
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Dimensionality-Reduced Antenna Modeling with Stochastically Established Constrained Domain
PublikacjaOver the recent years, surrogate modeling methods have become increasingly widespread in the design of contemporary antenna systems. On the one hand, it is associated with a growing awareness of numerical optimization, instrumental in achieving high-performance structures. On the other hand, considerable computational expenses incurred by massive full-wave electromagnetic (EM) analyses, routinely employed as a major design tool,...
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Trust Management Method for Wireless Sensor Networks
PublikacjaA Wireless Sensor Network (WSN) is a network of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. and to cooperatively pass their data to the main location. The first wireless network that bore any real resemblance to a modern WSN is the Sound Surveillance System (SOSUS), developed by the United States Military in the 1950s to detect and track Soviet...
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Cost-Efficient EM-Driven Size Reduction of Antenna Structures by Multi-Fidelity Simulation Models
PublikacjaDesign of antenna systems for emerging application areas such as the Internet of Things (IoT), fifth generation wireless communications (5G), or remote sensing, is a challenging endeavor. In addition to meeting stringent performance specifications concerning electrical and field properties, the structure has to maintain small physical dimensions. The latter normally requires searching for trade-off solutions because miniaturization...
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Electrocatalytic performance of oxygen-activated carbon fibre felt anodes mediating degradation mechanism of acetaminophen in aqueous environments
PublikacjaCarbon felts are flexible and scalable, have high specific areas, and are highly conductive materials that fit the requirements for both anodes and cathodes in advanced electrocatalytic processes. Advanced oxidative modi- fication processes (thermal, chemical, and plasma-chemical) were applied to carbon felt anodes to enhance their efficiency towards electro-oxidation. The modification of the porous anodes results in increased...
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The termostability, bioactive compounds and antioxidant activity of some vegetables subjected to different durations of boiling: investigation in vitro.
PublikacjaThis research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of theirbioactive compounds, antioxidant activity and thermostability. It was found that polyphenols (mg GAE/g), flavanols (mg GAE/g), flavonoids (mg CE/g), anthocyanins(mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots...
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Modeling external carbon addition in combined N-P activated sludge systems with an extension of the IWA Activated Sludge Models
PublikacjaThe aim of this study was to expand the IWA Activated Sludge Model No. 2d (ASM2d) to account for a newly defined readily biodegradable substrate that can be consumed by polyphosphate accumulating organisms (PAOs) under anoxic and aerobic conditions, but not under anaerobic conditions. The model change was to add a new substrate component and process terms for its use by PAOs and other heterotrophic bacteria under anoxic and aerobic...
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Modeling external carbon addition in combined N-P activated sludge systems with an extension of the IWA Activated Sludge Models
PublikacjaThe aim of this study was to expand the IWA Activated Sludge Model No. 2d (ASM2d) to account for a newly defined readily biodegradable substrate that can be consumed by polyphosphate accumulating organisms (PAOs) under anoxic and aerobic conditions, but not under anaerobic conditions. The model change was to add a new substrate component and process terms for its use by PAOs and other heterotrophic bacteria under anoxic and aerobic...
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Compulsive sexual behavior and dysregulation of emotion
PublikacjaIntroduction Dysregulation of emotion (DE) is commonly seen in individuals suffering from compulsive sexual behavior (CSB), as well as represents a crucial element of its common comorbidities like mood, anxiety, and substance use disorders. Aim To investigate the links between CSB and DE. Methods A review of pertinent literature on CSB and DE was performed using EBSCO, PubMed, and Google Scholar databases. Main Outcome Measure...
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Wybrane problemy szlifowania powierzchni płaskich z kinematyką docierania
PublikacjaW pracy przedstawiono teoretyczne i doświadczalne podstawy szlifowania powierzchni płaskich z kinematyką docierania. Dokonano kompleksowej analizy zastosowanych układów kinematycznych szlifierek. Przeprowadzono eksperymenty szlifowania jednostronnego ściernicami o spoiwie galwanicznym z ziarnami diamentowymi (D107, D64 i D46) oraz z regularnego azotku boru (B107 i B64). Innowacyjność ściernic polegała na zróżnicowanym utwierdzeniu...
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Entrepreneurial intentions of students from Latvia, Poland, and Ukraine: The role of perceived entrepreneurial education results
PublikacjaOur main aim is to establish which factors influence entrepreneurial intentions, with a particular focus on the role of entrepreneurial education and university support in Central and Eastern European countries (CEE). To verify hypotheses quantitative research was conducted using surveys among 2,085 first-year undergraduate students from three technical universities in three countries: Latvia, Poland and Ukraine. The results of...
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Comparing Apples and Oranges: A Mobile User Experience Study of iOS and Android Consumer Devices
PublikacjaWith the rapid development of wireless networks and the spread of broadband access around the world, the number of active mobile user devices continues to grow. Each year more and more terminals are released on the market, with the smartphone being the most popular among them. They include low-end, mid-range, and of course high-end devices, with top hardware specifications. They do vary in build quality, utilized type of material,...
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Exposure to Bisphenol A Analogs and the Thyroid Function and Volume in Women of Reproductive Age—Cross-Sectional Study
PublikacjaBisphenols (BPs) are commonly known plastifiers that are widely used in industry. The knowledge about the impact of BPs on thyroid function is scarce. Proper thyroid functioning is especially important for women of reproductive age, as hypothyroidism affects fertility, pregnancy outcomes and the offspring. There are no studies analyzing the influence of BPs on thyroid function and volume in non-pregnant young women. The aim of...
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Thermoluminescence glow curves and deconvoluted glow peaks of Ge doped flat fibers at ultra-high doses of electron radiation
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Pavement ageing influence on tyre/road noise
PublikacjaRoad surface should be constructed in a way that ensures safe and comfortable traffic conditions, not only when it is newly paved but also during its entire lifetime. An important factor in the asphalt mixture design process is also the expected pavement durability and stability of pavement properties over time. In many countries, road surface starts to play a significant role in traffic noise reduction actions. Selecting a particular...
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Highly crystalline colloidal nickel oxide hole transport layer for low-temperature processable perovskite solar cell
PublikacjaHighly crystalline NiOX usually requires high annealing temperature (>300 °C) which is incompatible with flexible substrate and might consume high amount of energy. Herein, we demonstrate a facile emulsion process to synthesize highly crystalline, low temperature deposition (<150 °C) and solution processable NiOx nanoparticles (NPs) as a hole transport layer for the perovskite solar cells (PVSCs)....
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Determination of the Major By-Products of Citrus hystrix Peel and Their Characteristics in the Context of Utilization in the Industry
PublikacjaKaffir lime (Citrus hystrix) is a popular citrus in Southeast Asia. Despite the growing interest in the peel of the fruit, the leaves are the most frequently used part of the fruit. The aim of the study was to determine the main by-products of the peel, such as pectins, minerals, essential oil, and bioactive compounds, and to evaluate the possibility of using them in various branches of industry. In the study of the essential oil...
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Modelowanie systemów energetycznych wytwarzania energii elektrycznej i ciepła do celów planowania rozwoju - wybrane zagadnienia
PublikacjaSystemy energetyczne wymagają przemian technologicznych w kierunku neutralności klimatycznej. W Polsce, w której systemie elektroenergetycznym i systemach ciepłowniczych dominują przestarzałe elektrownie i ciepłownie węglowe, dążenie do minimalizacji wpływu na środowisko wiąże się z wysokimi kosztami. Dlatego należy szukać optymalnych ścieżek roz-woju energetyki, aby osiągnąć ambitne długoterminowe cele strategiczne, przy minimalizacji...
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On Nature-Inspired Design Optimization of Antenna Structures Using Variable-Resolution EM Models
PublikacjaNumerical optimization has been ubiquitous in antenna design for over a decade or so. It is indispensable in handling of multiple geometry/material parameters, performance goals, and constraints. It is also challenging as it incurs significant CPU expenses, especially when the underlying computational model involves full-wave electromagnetic (EM) analysis. In most practical cases, the latter is imperative to ensure evaluation reliability....
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Sterownik PLC jako urządzenie IED zgodne ze standardem IEC 61850
PublikacjaWraz z rozwojem elektroenergetyki, w stacjach i sieciach elektroenerge- tycznych instalowanych jest coraz więcej cyfrowych urządzeń i układów realizujących złożone funkcje sterowni- cze, nadzorujące i zabezpieczeniowe [1] [2]. Obecnie, większość z tych urządzeń standardowo umożliwia również zdal- ne sterowanie, monitoring i akwizycję danych, wykorzystując jeden z wielu protokołów opracowanych dla prze- mysłowych...
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Study of Multi-Class Classification Algorithms’ Performance on Highly Imbalanced Network Intrusion Datasets
PublikacjaThis paper is devoted to the problem of class imbalance in machine learning, focusing on the intrusion detection of rare classes in computer networks. The problem of class imbalance occurs when one class heavily outnumbers examples from the other classes. In this paper, we are particularly interested in classifiers, as pattern recognition and anomaly detection could be solved as a classification problem. As still a major part of...
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Zastosowanie trendów przełącznikowych w analizie płac realnych w Polsce
PublikacjaStreszczenie W początkowej części artykułu zostały przedstawione i omówione informacje o poziomie miesięcznych nominalnych płac (WN) oraz indeksie cen dóbr konsumpcyjnych (ICK) w gospodarce polskiej w latach 1995-2015. Następnie opisano poziomy realnych płac (W) wyrażone w cenach roku 2015. Na bazie tych informacji przedstawiono i przedyskutowano zagadnienia dotyczące rocznych przyrostów płac realnych oraz ich rocznych stóp wzrostu....
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Essays on China's international trade - focus on One-Belt One-Road initiative
PublikacjaThis thesis explores China's international trade from trade, global value chains (GVCs) and export diversity, focusing on the "One-Belt One-Road" (OBOR) initiative proposed at the end of 2013. Specifically, I verify the potential association of OBOR with bilateral imports and exports in the first chapter. Then the relationship between OBOR and GVCs has been explored in Chapter 2. And I have extended the research in GVCs to China's...
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TIME- AND FREQUENCY-DOMAIN QUASI-2D SMALL-SIGNAL MOSFET MODELS
PublikacjaA novel approach to small-signal MOSFET modeling is presented in this book. As a result, time- and frequency-domain physics-based quasi-2D NQS four-terminal small-signal MOSFET models are proposed. The time-domain model provides the background to a novel DIBL-included quasi‑2D NQS four-terminal frequency-domain small-signal MOSFET model. Parameters and electrical quantities of the frequency-domain model are described by explicit...