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Search results for: inverse saddle
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Buzz-based recognition of the honeybee colony circadian rhythm
PublicationHoneybees are one of the highly valued pollinators. Their work as individuals is appreciated for crops pollination and honey production. It is believed that work of an entire bee colony is intense and almost continuous. The goal of the work presented in this paper is identification of bees circadian rhythm with a use of sound-based analysis. In our research as a source of information on bee colony we use their buzz that have been...
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Various cases of preservation and adaptive reuse Heritage Buildings in the Port of Gdynia
PublicationThe port of Gdynia contains a diverse range of heritage assets, starting with its spatial layout which is an urban concept designed in the first half of the 1920s. It is important to point out, this historically-shaped harbor space is preserved in its general idea and still functioning in port activities. Another significant element is the structural, technological solution which was the basis for constructing the entire port area...
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Study of the NO2 sensing mechanism of PEDOT-RGO film using in situ Raman Spectroscopy
PublicationIn this work, the mechanism of the NO2 reaction with PEDOT-RGO composite film has been investigated via in situ Raman spectroscopy. Reduced graphene oxide (RGO), poly(3,4-ethylenedioxytiophene)-reduced graphene oxide (PEDOT-RGO) and poly(3,4-ethylenedioxytiophene)/ClO4− (PEDOT/ClO4−) films were fabricated using an electrodeposition method and used as resistance sensors of gaseous nitrogen dioxide. The experimental results indicate...
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KONCEPCJA DWU-ŚMIGŁOWEJ ELEKTROWNI WIATROWEJ I ELEKTROWNI SZCZYTOWO-POMPOWEJ NA WZGÓRZU SZUBIENICZNYM
PublicationDogodne warunki terenowe Wzgórza Szubienicznego w Gdańsku oraz istniejąca tam infrastruktura stanowią podstawę do rozważenia koncepcji doposażenia instalacji badawczej Laboratorium Innowacyjnych Technologii Elektroenergetycznych i Integracji Odnawialnych Źródeł Energii LINTE^2 w skojarzony, hydro-wiatrowy zespół wytwórczy. W artykule zaproponowano koncepcję budowy elektrowni pompowo-szczytowej z turbinami Francisa oraz elektrowni...
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Sektorowe zróżnicowanie płynności finansowej przed-siębiorstw
PublicationPłynność finansowa warunkuje prawidłowość funkcjonowania całej firmy. Uzależniona jest od niej możliwość przetrwania przedsiębiorstwa na rynku oraz perspektywa jego rozwoju. Artykuł podejmuje tematykę zróżnicowania płynności finansowej przedsiębiorstw w zależności od ich przynależności sek-torowej. Z przeprowadzonych badań wynika, że wartość wskaźników z obsza-ru płynności finansowej jest silnie zróżnicowana w przekroju sektorowym....
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Metodyka projektowania i eksploatacji dróg szynowych z wykorzystaniem mobilnych pomiarów satelitarnych
PublicationW pracy zostały przedstawione aplikacyjne możliwości metody mobilnych pomiarów satelitarnych w projektowaniu i eksploatacji dróg szynowych. Pokazano wizualizację położenia toru kolejowego, omówiono sposoby oceny odcinków prostych toru i odcinków położonych w łuku oraz tworzenie poligonu kierunków głównych trasy. Szczególną uwagę poświęcono opracowanej analitycznej metodzie projektowania, omawiając jej algorytmy obliczeniowe: projektowania...
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Potencjał strategii slow city dla rozwoju miast kształtujących się metropolii polskich. Na przykładzie Pucka i Kartuz miast Obszaru Metropolitalnego Gdańsk-Sopot-Gdynia
PublicationW artykule wskazano możliwości wykorzystania filozofii ruchu Slow, do wykształcenia nowego modelu Metropolitalnych Slow City (MSC). Odniesiono się do założeń ruchu Cittaslow, pokazując potencjały dla alternatywnego kierunku strategii rozwojowej w duchu „miast dobrego życia” dla ośrodków w granicach obszarów metropolitalnych. W podsumowaniu założenia teoretyczne zilustrowano przykładem innowacyjnego modelu projektu rewitalizacji...
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Determination of short-chain monocarboksylic acids in cattle farm and dairy industry wastewater
PublicationThe paper describes application of various techniques to determine short-chain monocarboksylic acids (SCMAs) in samples from the successive steps from milk production: from wastewater from cattle farm to wastewater from dairy industry. Each technique of sample preparation is followed by gas chromatographic analysis.
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EM-Driven Size Reduction and Multi-Criterial Optimization of Broadband Circularly-Polarized Antennas Using Pareto Front Traversing and Design Extrapolation
PublicationMaintaining small size has become an important consideration in the design of contemporary antenna structures. In the case of broadband circularly polarized (CP) antennas, miniaturization is a challenging process due to the necessity of simultaneous handling of electrical and field properties (reflection, axial ratio, gain), as well as ensuring sufficient frequency range of operation, especially at the lower edge of the antenna...
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Performance-Driven Surrogate Modeling of High-Frequency Structures
PublicationThe 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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Shape-controllable synthesis of GdVO4 photocatalysts and their tunable properties in photocatalytic hydrogen generation
PublicationNovel visible light responsive materials for water splitting are essential for the efficient conversion of solar energy into hydrogen bond energy. Among other semiconductors, gadolinium orthovanadate has appropriate conduction and valence band edges positioned to split water molecules and a narrow band gap that allows the use of visible light for hydrogen generation. Thus, we present here that hydrogen evolution under visible light...
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Wire Arc Additive Manufactured Mild Steel and Austenitic Stainless Steel Components: Microstructure, Mechanical Properties and Residual Stresses
PublicationWire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and other alternative heat sources such as laser and electron beams, the process is currently receiving much attention in the industrial production sector. The gas...
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Advanced polarization sensitive analysis in optical coherence tomography
PublicationThe optical coherence tomography (OCT) is an optical imaging method, which is widely applied in variety applications. This technology is used to cross-sectional or surface imaging with high resolution in non-contact and non-destructive way. OCT is very useful in medical applications like ophthalmology, dermatology or dentistry, as well as beyond biomedical fields like stress mapping in polymers or protective coatings defects detection....
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Development and Validation of SPE-HPLC-MS/MS Method for Determining Cyclophosphamide in Surface Waters
PublicationA rapid and selective method for trace amounts determination of cyclophosphamide in surface water samples has been developed. A solid phase extraction SPE method for extraction and clean-up procedure has been optimized for determination by reversed-phase high-performance liquid chromatography with tandem mass spectrometry. The analyses proceed in the positive ion mode by means of the electrospray ionization method (ESI). Clean...
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Corporate social responsibility and forward default risk under firm and industry heterogeneity
PublicationObjective: This study aims to evaluate the impact of corporate social responsibility on forward default risk (FDR) under the setting of firm and industry heterogeneity. Research Design & Methods: This study evaluated the impact of corporate social responsibility (CSR) on FDR using the data of 497 companies from 2007-2021 in the S&P 500 index, taking into account firm and industry heterogeneity aspects. This study utilized instrumental...
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Regulacja napięcia w sieci nN z rozproszonymi źródłami energii
PublicationPodłączanie rozproszonych źródeł energii do sieci energetycznych niskiego napięcia powoduje powstawanie problemów zmienności i niesymetrii napięcia, zwłaszcza w przypadku dużych odległości od transformatora zasilającego. W skrajnych przypadkach zachodzi konieczność redukcji mocy generowanej przez źródło podczas oddawaniu energii do sieci. Rozwiązaniem tego problemu jest zastosowanie energoelektronicznego regulatora napięcia składającego...
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Metody strojenia regulatorów typu PID z wykorzystaniem technologii syntezy regulatorów od stanu
PublicationUkłady sterujące typu PID są jednymi z najbardziej popularnych regulatorów wykorzystywanych w układach regulacji. W związku z tym znanych jest szereg metod doboru wartości ich parametrów (nastaw). Obok różnych metod inżynierskich czy analitycznych strojenia tego typu regulatorów, dostępne są również podejścia bazujące na optymalizacji. Wskaźnikiem jakości znajdującym w nich zastosowanie jest np. całka z kwadratu uchybu. W artykule...
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Analiza danych osobowych przetwarzanych w systemach telekomunikacyjnych klasy IP PBX oraz metod ich anonimizacji za pomocą systemów SBC
PublicationOpisano wyniki realizacji pracy, dotyczącej analizy systemu telekomunikacyjnego, opartego na technologii VoIP, pod względem wymagań prawnych powstałych wraz z wejściem w życie przepisów Ogólnego Rozporządzenia o Ochronie Danych Osobowych (RODO). Przedstawiono wyniki analizy przykładowego systemu IP PBX Asterisk oraz wykorzystywanego w nim protokołu sygnalizacyjnego SIP, w kontekście przetwarzania danych osobowych, a także metody...
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Wpływ technicznych włókien celulozowych na wybrane właściwości kompozytów kauczuku naturalnego
PublicationCelem niniejszej pracy było zbadanie wpływu technicznych włókien celulozowych (dodanych w ilości 10, 20, 30 i 40 phr) jako naturalnego napełniacza na wybrane właściwości kompozytów na osnowie kauczuku naturalnego. Zbadano właściwości wulkanizatów przy statycznym rozciąganiu, w próbie rozdzierności, a także twardość, elastyczność przy odbiciu oraz ścieralność otrzymanych materiałów. Wyniki badań zostały porównane z wulkanizatem...
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Analiza przestrzenna sprzedaży paliw
PublicationZe względu na zmieniające się warunki i niepewność ekonomiczną gospodarowania, przeprowadzane badania dotyczące popytu na paliwa płynne dotyczą głównie zmian popytu w czasie, rzadziej w przestrzeni. Jednak rozwój narzędzi ekonometrycznych, który dokonał się w latach dziewięćdziesiątych, umożliwił nie tylko badania zmian popytu wynikające ze związków przyczynowo-skutkowych zachodzących w czasie, ale również w przestrzeni oraz w...
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Influence of pyrolysis atmosphere on the lithium storage properties of carbon-rich polymer derived SiOC ceramic anodes
PublicationPolymer derived carbon-rich SiOC ceramics are prepared from polysiloxane precursors through a pyrolysis process at 1000 °C using pure argon and argon/hydrogen mixture as pyrolysis atmosphere. The precursor is synthesized from a linear (Si–H)-containing polysiloxane cross-linked with divinylbenzene using hydrosilylation reaction in the presence of a platinum catalyst. Pyrolysis in Ar/H2 mixtures, compared to the treatment under...
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Transformational Leadership and Acceptance of Mistakes as a Source of Learning: Poland-USA Cross-Country Study
PublicationThis study explores the influence of transformational leadership on internal innovativeness mediated by mistakes acceptance, including country and industry as factors to be considered and gender and risk-taking attitude as moderators. General findings, primarily based on the US samples (healthcare, construction, and IT industry), confirmed that transformational leadership and internal innovativeness are mediated by mistakes acceptance...
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Analysis of the Possibilities of Applying 3D Print Methods for the Needs of Ship-Building Industry
PublicationArticle presents the analysis of applying additive and hybrid manufacturing methods and its impact on dynamic stiffness of prepared samples. Dynamic analysis of the handle bracket specimens consisted in plotting the resonance curves and using these curves to estimate the dynamic stiffness of elements produced with additive manufacturing technology. Authors focused especially on 3D print in Fused Deposiotion Modeling/Fused Filament...
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Study of the effect of residues of pharmaceuticals on the environment on the example of bioassay Microtox®
PublicationResidues of pharmaceuticals present in the aqueous environment can be found in a mixture of different substances wherein drugs not remain inert with respect to each other. In such mixtures a phenomenon of synergism or antagonism may occur, which can contribute to increase or decrease the overall toxicity of the mixture of drugs. Pharmaceuticals namely: diclofenac (sodium salt), oxyteracycline hydrochloride, fluoxetine hydrochloride,...
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Big Data Analytics for ICT Monitoring and Development
PublicationThe expanded growth of information and communication technology has opened new era of digitization which is proving to be a great challenge for researchers and scientists around the globe. The utmost paradigm is to handle and process the explosion of data with minimal cost and discover relevant hidden information in the least amount of time. The buzz word “BIG DATA” is a widely anticipated term with the potential to handle heterogeneous,...
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Virtual Whiteboard: A gesture-controlled pen-free tool emulating school whiteboard
PublicationIn the paper the so-called Virtual Whiteboard is presented which may be an alternative solution for modern electronic whiteboards based on electronic pens and sensors. The presented tool enables the user to write, draw and handle whiteboard contents using his/her hands only. An additional equipment such as infrared diodes, infrared cameras or cyber gloves is not needed. The user's interaction with the Virtual Whiteboard computer...
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Local electrochemical impedance spectroscopy in dynamic mode of galvanic coupling
PublicationA novel method that combines local electrochemical impedance spectroscopy and mapping in dynamicmode is proposed. Method was validated over two galvanic couplings, namely zinc/copper and cad-mium/copper. Impedance spectrum response for all measuring points was obtained by means ofsimultaneous implementation of selected range of frequencies. Proposed method allows the measure-ment in a more time-efficient manner, at the same time...
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Direct determination of cadaverine in the volatile fraction of aerobically stored chicken breast samples
PublicationTo supplement the currently used methods for poultry meat shelf life assessment, it might be necessary to develop a technique for rapid headspace analysis of volatiles with no prior sample preparation step. Biogenic amines, in particular cadaverine, are considered meat spoilage indicators. Described in this article are the results of a preliminary investigation of the applicability of proton transfer reaction mass spectrometry...
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Nanoindentation tests titanium alloy Ti-6Al-4V after interference laser treatment
PublicationThe study aimed was to assess selected mechanical properties of surface layers obtained after interference laser treatment – DLIL of titanium alloy Ti-6Al-4V used for implants. The samples were melted in still air at room temperature, for this purpose Nd:YAG laser was used, the number of laser shots was variable. Next, nanoindentation tests were performed, based on which Young’s modulus and nanohardness in the obtained surface...
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Scaling Up the Process of Titanium Dioxide Nanotube Synthesis and Its Effect on Photoelectrochemical Properties
PublicationIn this work, for the first time, the influence of scaling up the process of titanium dioxide nanotube (TiO2NT) synthesis on the photoelectrochemical properties of TiO2 nanotubes is presented. Titanium dioxide nanotubes were obtained on substrates of various sizes: 2 × 2, 4 × 4, 5 × 5, 6 × 6, and 8 × 8 cm2. The electrode material was characterized using scanning electron microscopy as well as Raman and UV–vis spectroscopy in order...
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Focused ion beam-based microfabrication of boron-doped diamond single-crystal tip cantilevers for electrical and mechanical scanning probe microscopy
PublicationIn this paper, the fabrication process and electromechanical properties of novel atomic force microscopy probes utilising single-crystal boron-doped diamond are presented. The developed probes integrate scanning tips made of chemical vapour deposition-grown, freestanding diamond foil. The fabrication procedure was performed using nanomanipulation techniques combined with scanning electron microscopy and focused ion beam technologies....
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EXAMINATION OF SOL-GEL DERIVED HYDROXYAPATITE ENHANCED WITH SILVER NANOPARTICLES USING OCT AND RAMAN SPECTROSCOPY
PublicationHydroxyapatite (HAp) has been attracting widespread interest in medical applications. In a form of coating, it enables to create a durable bond between an implant and surrounding bone tissues. With addition of silver nanoparticles HAp should also provide antibacterial activity. The aim of this research was to evaluate the composition of hydroxyapatite with silver nanoparticles in a non-destructive and non-contact way. For control measurements...
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The impact of cold plasma on the phenolic composition and biogenic amine content of red wine
PublicationThe effect of cold plasma (CP) on phenolic compound (PC) and biogenic amine (BA) contents of red wine was investigated for the first time. The influence of CP was compared with the effects of a wine preservation using potassium metabisulfite and a combined method. The PC profile was determined by UPLC-PDA-MS/MS while BAs using DLLME-GC–MS. Chemometric analysis also was used. The content of PCs was 3.1% higher in the sample preserved...
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An assessment of health status and health behaviours in adolescents: main points and methods of the SOPKARD-Junior programme.
PublicationThe study involved preparing and implementing a model of screening assessments for adolescents and comparison of anthropometric examinations between the population of the SOPKARD-Junior programme and representative sample of Polish children in the same years.Additionally, data concerning attendance rates for particular examinations carried out under SOPKARD-Junior programme were presented.Revier2,comment 1
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Investor confidence and high financial literacy jointly shape investments in risky assets
PublicationHouseholds consistently invest less in equities and bonds than predicted by economic theory. We explain this from a behavioral economics perspective and distributional analysis using rich US survey microdata. We find that higher investor self-confidence in her financial abilities and financial literacy jointly increase the probability of investing in equities. Conditional on participation, confidence in the macroeconomy additionally...
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Supporting Software Project Management Processes Using the Agent System
PublicationThe natural development of information technology area stimulates intense growth of various technologies which support basic organization processes. The range of technologies implies appropriate management thereof, as well as accurate correspondence with conducted activities. Abandonment of activities within individual branches in favour of project approach to performed assignments (especially those connected with software development)...
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Progress in module design for membrane distillation
PublicationThere have been tremendous advances in membrane distillation (MD) since the concept was introduced in 1961: new membrane designs and process configurations have emerged, and its commercial viability has been evaluated in several pilot-scale studies. However, its high energy consumption has hindered its commercialization. One of the most promising ways to overcome this obstacle is to develop more energy-efficient membrane modules....
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Improved maximum power point tracking algorithms by using numerical analysis techniques for photovoltaic systems
PublicationSolar photovoltaic (PV) panels generate optimal electricity when operating at the maximum power point (MPP). This study introduces a novel MPP tracking algorithm that leverages the numerical prowess of the predictor-corrector method, tailored to accommodate voltage and current fluctuations in PV panels resulting from variable environmental factors like solar irradiation and temperature. This paper delves into the intricate dynamics...
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A conceptual framework for digital tax administration - A systematic review
PublicationTax administrations worldwide have become highly digitised with a diverse and sophisticated array of e-services to enhance the taxpayer experience. Nevertheless, given the high rates of failure of e-government services, it is critical to understand the factors that are essential to the success of a digital tax system. Drawing on a systematic review of ninety-six publications across the digital taxation, taxation, and information...
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INTRODUCING GREENERY INTO A BUILDING BASED ON ITS IMPACT ON HUMAN WELLBEING - REVIEW OF THEORIES AND METHODS IN ARCHITECTURE
PublicationGreenery around and within buildings is an integral part of architectural space. Although science is providing more and more knowledge about the impact of greenery on human well-being, there is still a lack of guidelines on how to apply this knowledge in architectural design. The purpose of this review article is to prepare the ground for further research on how to support architectural design in integrating greenery as a co-creative...
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Fault-tolerant performance of the novel five-phase doubly-fed induction generator
PublicationThe article presents the concept of a new design of a multi-phase doubly-fed induction generator (DFIG). The innovative design approach uses a five-phase power supply from the rotor side of the generator with a three-phase classic stator power supply. Modern three-phase doubly-fed induction generators are the dominant choice for Wind Energy Conversion Systems (WECS). Solutions of this type are sensitive to the loss of at least...
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Topological extraordinary optical transmission
PublicationΤhe incumbent technology for bringing light to the nanoscale, the near-field scanning optical microscope, has notoriously small throughput efficiencies of the order of 10^4-10^5 or less. We report on a broadband, topological, unidirectionally guiding structure, not requiring adiabatic tapering and, in principle, enabling near-perfect (∼100%) optical transmission through an unstructured single arbitrarily subdiffraction slit at...
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Bio-mitigation of organic pollutants using horseradish peroxidase as a promising biocatalytic platform for environmental sustainability
PublicationA wide array of environmental pollutants is often generated and released into the ecosystem from industrial and human activities. Antibiotics, phenolic compounds, hydroquinone, industrial dyes, and Endocrine-Disrupting Chemicals (EDCs) are prevalent pollutants in water matrices. To promote environmental sustainability and minimize the impact of these pollutants, it is essential to eliminate such contaminants. Although there are...
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Coastline change-detection method using remote sensing satellite observation data
PublicationCoastal zones are not only the fundaments for local economics based on trade, shipping and transport services, but also a source of food, energy and resources. Apart from offering diverse opportunities for recreation and tourism, coastal zones provide protection against storms and other meteorological disturbances. Environmental information is also essential because of the direct influence on a country’s maritime zones, which are...
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Comparison of heat transfer characteristics in surface cooling with boiling microjets of water, ethanol and HFE7100
PublicationThe basis of microjet technology is to produce jets which impinge the surface at the stagnation point with a very high kinetic energy. Main objective of this paper was to investigate the physical phenomena occurring on solid surfaces upon impingement of the single microjet in case of three fluids, namely water, ethanol and HFE7100. Intense heat transfer in the impact zone of microjet has been examined and described with precise...
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Heat transfer characteristics of hybrid microjet – Microchannel cooling module
PublicationThe paper presents experimental investigation of heat transfer intensification in a microjet–microchannel cooling module. Applied technology takes benefits from two very attractive heat removal techniques. When jets are impinging on the surface, they have a very high kinetic energy at the stagnation point, also in microchannels boundary layer is very thin allowing to obtain very high heat fluxes. Main objective of this paper was...
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Evolving gene regulatory networks controlling foraging strategies of prey and predators in an artificial ecosystem
PublicationCo-evolution of predators and prey is an example of an evolutionary arms race, leading in nature to selective pressures in positive feedback. We introduce here an artificial life ecosystem in which such positive feedback can emerge. This ecosystem consists of a 2-dimensional liquid environment and animats controlled by evolving artificial gene regulatory networks encoded in linear genomes. The genes in the genome encode chemical...
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Chromatographic lipophilicity determination using large volume injections of the solvents non-miscible with the mobile phase
PublicationA new perspective in the lipophilicity evaluation through RP-HPLC is permitted by analysis of the retentionfactor (k) obtained by injecting large volumes of test samples prepared in solvents immiscible withmobile phase. The experiment is carried out on representative groups of compounds with increasedtoxicity (mycotoxins and alkaloids) and amines with important biological activity (naturally occurringmonoamine compounds and related...
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Miniaturized Passive Emission Chambers for In Situ Measurement of Emissions of Volatile Organic Compounds
PublicationThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air. The presence of dangerous chemical compounds in indoor air can have an adverse impact on human health and cause numerous diseases of the respiratory and circulatory systems. Such harmful chemicals get into indoor air as a result of their emission from building and indoor materials....
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Bezczujnikowe sterowanie trakcyjnym silnikiem IPMSM małej mocy
PublicationThis paper describes an algorithm for estimation of IPMSM angular rotor position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. Control of the IPMSM electromagnetic torque requires a precise estimation of the rotor angular position throughout the wide speed range. This involves using a set of estimation methods switched with the dependence on the actual rotor...