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Search results for: efficiency
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Macromodeling techniques for accelerated finite element analysis
PublicationThis paper deals with the Model Order Reduction applied locally in the Finite Element Method (FEM) analysis. Due to the reduction process, blocks of FEM system matrices associated with selected subregions of the computational domain are projected onto the subspaces spanned by the vectors of suited orthogonal projection basis. In effect, large and sparse FEM matrices are replaced with small and dense ones, called macromodels. This...
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Adapting the pinch point analysis to improve the ORC design process
PublicationPinch point analysis can be adapted so as to assist in the early stages of designing the ORC systems. Typically used in determining the working parameters of heat exchangers, it can be employed to improve the heat fitting between the source of heat and the working fluids of the ORC system. To attain the parametric match, an algorithm was built enabling quick estimation of the possible heat reception by the specific working fluid....
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Novel 5.1 Downmix Algorithm with Improved Dialogue Intelligibility
PublicationA new algorithm for 5.1 to stereo downmix is introduced, which addresses the problem of dialogue intelligibility. The algorithm utilizes proposed signal processing algorithms to enhance the intelligibility of movie dialogues, especially in difficult listening conditions or in compromised speaker setup. To account for the latter, a playback configuration utilizing a portable device, i.e. an ultrabook, is examined. The experiments...
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The effect of laser on metal surfaces for multidisciplinary usage in material and thermal engineering
PublicationThe subject of heat transfer and cooling systems is still a matter of contention in many different fields of science and industry. Infrigidation is much more difficult than warming, and so, much more needed in more and more different devices, starting from massive industrial machinery and air conditioning in commercial buildings, up to micro and nano-surgery tools. In fact, the size of many cooling systems is still a problem. It...
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ZASTOSOWANIE MACIERZY PSEUDO ODWROTNEJ W METODACH ALOKACJI PĘDNIKÓW UKŁADU DYNAMICZNEGO POZYCJONOWANIA STATKU
PublicationUkłady kontroli alokacji pędników stanowią ważną część systemów dynamicznego pozycjonowania na statku. Określają one sygnały sterujące nastawami pędników, na podstawie uogólnionego wektora sił wzdłużnej, poprzecznej i momentu skręcającego, uzyskiwanych z prawa sterowania. W artykule przedstawiono wybrane algorytmy kontroli alokacji pędników, różniące się sposobem wyznaczania macierzy pseudo odwrotnej oraz algorytm bezpośredniej...
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Możliwości ograniczenia zużycia energii napędowej urządzeń przez optymalizację doboru wymienników ciepła, właściwą konfigurację i kontrolę przepływu płynów roboczych
PublicationArtykuł poświęcony możliwości ograniczenia zużycia energii napędowej urządzeń na drodze optymalizacji doboru wymienników ciepła, właściwej konfiguracji i kontroli przepływu płynów roboczych. Przedstawiono w nim ocenę zużycia energii w systemach energetycznych o największej energochłonności w realiach Polski. Zwrócono uwagę na możliwość wykorzystania wymienników ciepła o wysokiej efektywności dla zmniejszenia oporu przenoszenia...
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Electrohydrodynamic Flow Patterns in a Narrow Electrostatic Precipitator with Longitudinal Wire Electrode for Various Electrode Geometries
PublicationRecently narrow electrostatic precipitators (ESPs) have become a subject of interest because of their possible application in diesel engines. In this paper results of 2-dimensional (2D) Particle Image Velocimetry (PIV) measurements of the flow patterns in a narrow ESP for a various electrode geometries are presented. The PIV measurements were carried out in the observation plane that is perpendicular to the ESP duct. The ESP was...
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Hybrid constructed wetlands for the National Parks in Poland - a case study, requirements, dimensioning, preliminary results
PublicationWater and wastewater management, especially in rural areas, greatly affects loads of nutrients discharged to the Baltic Sea. In Poland, this management is unbalanced because of the dispersed development and in many locations con struction of sewerage system is uneconomic or even impossible. For this reason, a significant part of sewage from single-family houses in rural areas must be discharged into domestic sewage systems. The...
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Wastewater treatment by means of Advanced Oxidation Processes at basic pH conditions: A review
PublicationAdvanced oxidation processes (AOPs) have been used as an alternative and effective option for treatment of industrial wastewater, especially in the case of the non-biodegradable compounds. Despite of several well developed AOPs, the majority of them are effective only at acidic or neutral pH, namely Fenton related processes, making the list of available effective advanced oxidation technologies strongly limited. In many cases,...
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Modes of Failure Analysis in Reinforced Concrete Beam Using Laser Scanning and Synchro-Photogrammetry
PublicationThe following paper reveal the limitations and possibilities of terrestrial laser scanning technology adaptation in diagnostics of reinforced concrete beams. In this paper, authors present potential spectrum of TLS use in modes of failure analysis of R-C beams and determines under which conditions the laser technologies might be applied. Research was carried out at the Regional Laboratory of Structural Engineering at Gdansk University...
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The use of constructed wetlands for the treatment of industrial wastewater
PublicationConstructed wetlands are characterized by specific conditions enabling simultaneous various physical and biochemical processes. This is the result of specific environment for the growth of microorganisms and hydro-phytes (aquatic and semiaquatic plants) which are capable of living in aerobic, anaerobic and facultative anaerobic conditions. Their interaction contributes to the intensification of oxidation and reduction responsible...
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Analysis of different tillage implements with respect to reduced fuel consumption, tractor operating speed and its wheel slippage
PublicationNowadays the prices of agricultural farm produced products are increasing with ant-speed and the prices of input for raising crops are increasing with rocket-speed. Therefore, there is a dire need to conduct some important studies to innovate the techniques which can lower the costs of crop production. In this context, this study was conducted to evaluate the consumption of fuel at different tillage implements, tractor operating...
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Different design aspects of an Organic Rankine Cycle turbine for electricity production using a geothermal binary power plant
PublicationIn recent years, pressure has been growing to increase the share of renewable energy sources in electricity generation, which may offer opportunities for the development of geothermal energy in regions that have been so far considered unprofitable in this respect. One such country currently undergoing an energy transition is Poland in which low-temperature geothermal resources are currently used for district heating and recreation...
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Influence of the low ambient temperature on the start-up process of hydraulic pumps
PublicationStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of pressure drop in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump working chambers with...
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25 years of research and experiences about the application of constructed wetlands in southeastern Poland
PublicationThis paper is a review of research and experiences related to the application of constructed wetland systems (CWs) in southeastern Poland in 1992–2016. On the basis of literature data, a comparison between pollutant removal efficiencies of one-stage and hybrid CWs was made. Some problems regarding the operation of these treatment plants were also presented. Data from various facilities indicate that one-stage CWs with horizontal...
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Denitrifcation rate in the mainstream deammonification
PublicationThe conventional processes of biological nitrogen removal based on nitrification and denitrification does not fit properly into the concept of the circular economy. As the alternative one should consider the deammonification process, which is a combination of partial nitrification (nitritation) and Anammox processes. It consists of removing ammonium nitrogen from wastewater under anaerobic conditions by a group of autotrophic microorganisms....
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Cyclodextrin polymers as efficient adsorbents for removing toxic non-biodegradable pimavanserin from pharmaceutical wastewaters
PublicationPresence of even small amount of active pharmaceutical ingredients in the environment carries risks tohuman and animal health, presenting an important issue. The paper presents issues related to the newdrug - pimavanserin (PMV). Biological treatment efficiency of pimavanserin (PMV) was evaluated usinglab-scale Sequencing Batch Reactor (SBR). It has been shown to have a negative effect on aquatic or-ganisms by classifying it as...
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Long-term operating conditions for different sorption materials to capture phosphate from domestic wastewater
PublicationThis paper presents the results of a study on the possibility of applying various configured filters filled with a mixture of Rockfos® and Leca® material for the effective capture of phosphate from domestic wastewater. The tests were carried out for two years at two wastewater flow rates (20 and 40 L/day) in three pairs of filtration columns with a volume of filter material equal to 20 liters each. Columns 1A and 1B were filled...
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Understanding the Electronic Structure and Optical Properties of Vacancy-Ordered Double Perovskite A2BX6 for Optoelectronic Applications
PublicationOver the past few years, metal halide perovskite solar cells have made significant advances. Currently, the single-junction perovskite solar cells reach a conversion efficiency of 25.7%. Perovskite solar cells with a wide band gap can also be used as top absorber layers in multi-junction tandem solar cells. We examined the dynamical and thermal stability, electronic structure, and optical features of In2PtX 6 (X = Cl, Br, and I)...
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Evaluation of polycaprolactone as a new sorbent coating for determination of polar organic compounds in water samples using membrane–SPME
PublicationCommercially available solid-phase microextraction fibers used for isolation of polar analytes are based on the adsorption phenomenon. In consequence, typical limitations bonded with analytes displacement and matrix effects are very frequent. In the present study, alternative solution is described. Polycaprolactone (PCL) was used for the first time as sorbent to isolate polar organic compounds from water samples using the membrane–solid-phase...
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Modes of Failure Analysis in Reinforced Concrete Beam Using Laser Scanning and Synchro-Photogrammetry - How to apply optical technologies in the diagnosis of reinforced concrete elements?
PublicationThe following paper reveal the limitations and possibilities of terrestrial laser scanning technology adaptation in diagnostics of reinforced concrete beams. In this paper, authors present potential spectrum of TLS use in modes of failure analysis of R-C beams and determines under which conditions the laser technologies might be applied. Research was carried out at the Regional Laboratory of Structural Engineering at Gdansk University...
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Portable raman spectrometer for maritime security applications
PublicationThe fast identification of explosives, narcotics and other chemicals carried on board of ships or transported in containers to the harbors is an important problem of maritime security. Raman spectroscopy is widely used for fast identification of various chemicals. Continuous progress in the field of photonics has resulted in commercial availability of low-power compact Raman spectrometers which can be integrated into portable systems....
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Fast, sensitive and reliable multi-residue method for routine determination of 34 pesticides from various chemical groups in water samples by using dispersive liquid – liquid microextraction coupled with gas chromatography – mass spectrometry
PublicationA simple and efficient dispersive liquid-liquid microextraction technique (DLLME) was developed by using a mixture of two solvents: 40 μL of tetrachlorethylene (extraction solvent) and 1.0 mL of methanol (disperser solvent), which was rapidly injected with a syringe into 10mL ofwater sample. Some important parameters affecting the extraction efficiency, such as type and volume of solvents, water sample volume, extraction time,...
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Waste materials assessment for phosphorus adsorption toward sustainable application in circular economy
PublicationPhosphorus is the main determinant of nutrient enrichment in the water bodies. Many resources including nutrients may be shortly exhausted, assuming current consumption. This scenario leads to growing interest in resources recovery and/or reuse, which together with sustainable energy consumption and waste reduction are the main courses of the circular economy. Usage of coagulants in wastewater treatment plants (WWTP) does not allow...
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Synthesis of Cyano-Benzylidene Xanthene Synthons Using a Diprotic Brønsted Acid Catalyst, and Their Application as Efficient Inhibitors of Aluminum Corrosion in Alkaline Solutions
PublicationNovel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene–aldehyde compound. Different xanthene concentrations (ca. 0.1–2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were...
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Magnetic deep eutectic solvents as efficient media for extraction of furfural and 5-hydroxymethylfurfural from aqueous samples
PublicationThe extraction of furfural (FF) and 5-hydroxymethylfurfural (HMF) from hydrolysates is currently one of the main challenges in bio-refinery. In this work, the separation of FF and HMF from the aqueous phase was carried out using a new type of green solvents – Magnetic Deep Eutectic Solvents (MDES). A conductor-like screening model for realistic solvents (COSMO-RS) was used for the preselection of 400 MDES. MDES which exhibit the...
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Sonocatalytic degradation of Bisphenol A from aquatic matrices over Pd/CeO2 nanoparticles: Kinetics study, transformation products, and toxicity
PublicationIn this work, different ratios of palladium – cerium oxide (Pd/CeO2) catalyst were synthesized and characterized, while their sonocatalytic activity was evaluated for the degradation of the xenobiotic Bisphenol A (BPA) from aqueous solutions. Sonocatalytic activity expressed as BPA decomposition exhibited a volcano-type behavior in relation to the Pd loading, and the 0.25Pd/CeO2 catalyst characterized by the maximum Pd dispersion...
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Processing of Biomass Prior to Hydrogen Fermentation and Post-Fermentative Broth Management
PublicationUsing bioconversion and simultaneous value-added product generation requires purifica- tion of the gaseous and the liquid streams before, during, and after the bioconversion process. The effect of diversified process parameters on the efficiency of biohydrogen generation via biological pro- cesses is a broad object of research. Biomass-based raw materials are often applied in investigations regarding biohydrogen generation using...
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Photocatalytic degradation and pollutant-oriented structure-activity analysis of carbamazepine, ibuprofen and acetaminophen over faceted TiO2
PublicationPhotocatalytic degradation of carbamazepine, ibuprofen, acetaminophen and phenol was studied in the presence of anatase photocatalyst, exposing three different crystal facets in the majority of {0 0 1}, {1 0 0} or {1 0 1}. It was found that octahedral anatase particles exposing {1 0 1} facets allow to achieve the best degradation and mineralization of all persistent organic pollutants. This confirms that the previous findings,...
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Computational Complexity and Its Influence on Predictive Capabilities of Machine Learning Models for Concrete Mix Design
PublicationThe design of concrete mixtures is crucial in concrete technology, aiming to produce concrete that meets specific quality and performance criteria. Modern standards require not only strength but also eco-friendliness and production efficiency. Based on the Three Equation Method, conventional mix design methods involve analytical and laboratory procedures but are insufficient for contemporary concrete technology, leading to overengineering...
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Integracja bezprzewodowych heterogenicznych sieci IP dla poprawy efektywności transmisji danych na morzu
PublicationWraz ze wzrostem istotności środowiska morskiego w naszym codziennym życiu np. w postaci zwiększonego wolumenu transportu realizowanego drogą morską. czy zintensyfikowanych prac dotyczących obserwacji i monitoringu środowiska morskiego, wzrasta również potrzeba opracowania efektywnych systemów komunikacyjnych dedykowanych dla tego środowiska. Heterogeniczne systemy łączności bezprzewodowej integrowane na poziomie warstwy sieciowej...
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Initial Considerations
PublicationChemical processes have made use of a wide number of volatile organic solvents due to their efficiency in countless unit operations. The increasing knowledge on the environmental, health, and safety hazards associated to their use has significantly contributed to the search for greener alternatives. The primary purpose of this book is to provide an overview of alternative solvents with reduced issues that have successfully replaced...
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Self–Organizing Map representation for clustering Wikipedia search results
PublicationThe article presents an approach to automated organization of textual data. The experiments have been performed on selected sub-set of Wikipedia. The Vector Space Model representation based on terms has been used to build groups of similar articles extracted from Kohonen Self-Organizing Maps with DBSCAN clustering. To warrant efficiency of the data processing, we performed linear dimensionality reduction of raw data using Principal...
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Recent progress in research on the cutting processes of wood. A review COST Action E35 2004-2008: Wood machining - micromechanics and fracture
PublicationZaprezentowano postępy w badaniach przecinania drewna ze szczególnym uwzględnieniem nowych metod dedykowanych zwiększeniu wydajności materiałowej w tartacznictwie. Zademonstrowano przydatność współczesnej mechaniki pękania do szacowania mocy skrawania dla pił, których wartości rozwarcia są różne od pił użytych w badaniach skrawalnościowych. W tych ostatnich wyznaczano wiązkość materiału obrabianego oraz naprężenia tnące. Badania...
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Shipping Safety Management on Polish Inland Waterways
PublicationOver the past years, the role of inland waterway transport has increased compared to other modes of transport. The increasing intensity of the inland vessel traffic significantly affects the safety of navigation. The article analyses the main causes of accidents and incidents that occurred on the Odra Waterway and Lower Vistula. The authors have classified those accidents and suggested possible directions for the development of...
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A Biofeedback System that Uses the Game to Study Electrical Muscle Activity
PublicationThe aim of this project was to design a system that will allow performing repetitive muscle exercises using a biofeedback device. It is supposed to enhance the motivation and attractiveness of the performed tasks thanks to an interactive game developed for mobile devices with the Android operating system. The built-in calibration mechanisms enable the users to play a game that is independent of their abilities which evens out the...
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BIOVAC® WASTEWATER TREATMENT PLANTS IN THE MOUNTAIN NATIONAL PARKS.
PublicationThis paper presents characteristics of the Biovac® wastewater treatment plants operating in the mountain areas of the Polish national parks (NP): Tatrzanski NP and Babiogórski NP as well as in the West Spitsbergen NP. On the basis of the laboratory tests performed on raw sewage and the final effluent the efficiency of the wastewater treatment plants was evaluated. It was found that high COD values and rather high COD / BOD5 ratios...
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The Concept of a Methodology for Selecting the Optimal Parameters of Heat Received from a Nuclear Power Plant Operating in a Partial Cogeneration Mode
PublicationThe paper presents the concept of the objective function which is to allow the selection of optimal parameters of the district heating system using a nuclear power plant operating in partial cogeneration mode. The concept is based on research carried out a number of years ago. The size of annual expenses was proposed as the objective function, which allows to compare the operation of a nuclear power plant in partial cogeneration...
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On root finding algorithms for complex functions with branch cuts
PublicationA simple and versatile method is presented, which enhances the complex root finding process by eliminating branch cuts and branch points in the analyzed domain. For any complex function defined by a finite number of Riemann sheets, a pointwise product of all the surfaces can be obtained. Such single-valued function is free of discontinuity caused by branch cuts and branch points. The roots of the new function are the same as the...
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Instantaneous Impedance Analysis of Non-Stationary Corrosion Process: a Case Study of Carbon Steel in 1M HCl
PublicationThe paper concerns the problem of evaluation of stationarity of carbon steel corrosion in 1M HCl. Comparison of corrosion rate with addition of corrosion inhibitor to the reference measurement is the most often used way of evaluating inhibitor efficiency. Such an approach is valid only if corrosion rate is a stationary process. Two complementary techniques were used simultaneously: volumetric analysis of evolved hydrogen and instantaneous...
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Self-Organizing Map representation for clustering Wikipedia search results
PublicationThe article presents an approach to automated organization of textual data. The experiments have been performed on selected sub-set of Wikipedia. The Vector Space Model representation based on terms has been used to build groups of similar articles extracted from Kohonen Self-Organizing Maps with DBSCAN clustering. To warrant efficiency of the data processing, we performed linear dimensionality reduction of raw data using Principal...
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Fluctuation-enhanced scent sensing using a single gas sensor
PublicationScent or aroma sensing during aromatherapy can be carried out by applying only a single resistance gas sensor (TGS - Taguchi Gas Sensors). This paper considers the efficiency of detection of essential oils by DC resistance and its fluctuations observed in TGS sensors. A detailed study has been conducted for scents emitted by five popular essential oils using three sensor types (TGS 2600, TGS 2602, TGS 823). The research was focused...
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Koszty eksploatacyjne sprężarek chłodniczych
PublicationWielkością charakteryzującą efektywność sprężarki przy uwzględnieniu jej pracy przy zmiennych parametrach otoczenia jest europejski wskaźnik sezonowej efektywności energetycznej ESEER (European Seasonal Energy Efficiency Ratio). Wskaźnik ten obliczany jest z uwzględnieniem zmiany temperatury otoczenia, zapotrzebowania wydajności chłodniczej oraz czasu pracy sprężarek w ciągu roku. W artykule przedstawiono przykład doboru sprężarek...
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Analytical eco-scale for assessing the greenness of analytical procedures
PublicationWe propose the analytical eco-scale as a novel comprehensive approach to evaluating the greenness of analytical methodology. It is based on assigning penalty points to parameters of an analytical process that are not in agreement with the ideal green analysis. This approach compares different parameters and different steps of the analytical process. Traditional green chemistry metrics 9e.g. Atom Economy, E-factor and Reaction Mass...
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Recent progress in research on the cutting processes of wood. A review COST Action E35 2004-2008: Wood machining - micromechanics and fracture
PublicationZaprezentowano postępy w badaniach przecinania drewna ze szczególnym uwzględnieniem nowych metod dedykowanych zwiększeniu wydajności materiałowej w tartacznictwie. Zademonstrowano przydatność współczesnej mechaniki pękania do szacowania mocy skrawania dla pił, których wartości rozwarcia są różne od pił użytych w badaniach skrawalnościowych. W tych ostatnich wyznaczano wiązkość materiału obrabianego oraz naprężenia tnące. Badania...
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Aqueous Molybdate Provides Effective Corrosion Inhibition of WE43 Magnesium Alloy in Sodium Chloride Solutions
PublicationCorrosion and corrosion inhibition of WE43 magnesium alloy were investigated in NaCl solutions containing different amounts of sodium molybdate. Electrochemical, microscopic, and spectroscopic experiments were utilized to examine the mechanism of corrosion inhibition by molybdates. Electrochemical data showed that Na2MoO4 inhibitor provides reliable inhibition at concentrations at and above 100 mM. Raman and XPS spectroscopy demonstrated...
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Optimization model of agile team’s cohesion
PublicationTeam’s cohesion is one of the most important factors of IT project execution effectiveness. Optimization of team’s cohesion gives the possibility of reducing the risk of project failure. It also allows to increase the teamwork efficiency and thus optimize time of tasks execution, increase the guarantee of maintaining the scope of the project and the chance of achieving a given level of products quality. This article presents determination...
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Collective citizens' behavior modelling with support of the Internet of Things and Big Data
PublicationIn this paper, collective human behaviors are modelled by a development of Big Data mining related to the Internet of Things. Some studies under MapReduce architectures have been carried out to improve an efficiency of Big Data mining. Intelligent agents in data mining have been analyzed for smart city systems, as well as data mining has been described by genetic programming. Furthermore, artificial neural networks have been discussed...
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A multistage turbine for a micro power plant
PublicationThis paper presents results of a design analysis of a multi-stage turbine for the cogeneration micro-power plant working in accordance with Organic Rankine Cycle (ORC). The heat power of the plant is assumed equal to 20 kW and the corresponding available electric output is estimated to be of about 3 kW. Different variants of the radial and axial-flow turbines have been considered, while the detailed results of the calculations...
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Bacterial nanocellulose as a microbiological derived nanomaterial
PublicationBacterial nanocellulose (BNC) is a nanofibrilar polymer produced by strains such as Gluconacetobacter xylinus, one of the best bacterial species which given the highest efficiency in cellulose production. Bacterial cellulose is a biomaterial having unique properties such as: chemical purity, good mechanical strength, high flexibility, high absorbency, possibility of forming any shape and size and many others. Such a large number...