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Search results for: heart rate variability
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Removal of lead ions from wastewater using lanthanum sulfide nanoparticle decorated over magnetic graphene oxide
PublicationIn this study, the new lanthanum sulfide nanoparticle (La2S3) was synthesized and incorporated onto magnetic graphene oxide (MGO) sheets surface to produce potential adsorbent (MGO@LaS) for efficient removal of lead ions (Pb2+) from wastewater. The synthesized MGO@LaS adsorbent was characterized using Fourier transform infrared spectroscopy, field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. The...
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Studying of polyoxadiazole with Si atom in the backbone
PublicationPurpose: The aim of this paper is to show properties of spin-coated thin films of new polymer having siliconatom in the backbone. This amorphous polymer has appeared to be applied as active films in organic devices (asOLED).Design/methodology/approach: Thin films of 4-(diphenyl(4-(4-(5-(p-tolyoxy)phenyl)-1,3,4-oxadiazol-2-yl)phenyloamino)methyl)-phenyl)silyl)-1-methylbenzamide (Oxad–Si-B) were obtained by spin-coating method.The...
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Enhanced capacitance of composite TiO2 nanotube / boron-doped diamond electrodes studied by impedance spectroscopy
PublicationWe report on the novel composite nanostructures based on boron-doped diamond thin film grown on top of TiO2 nanotubes. The nanostructures made of BDD-modified titania nanotubes showed an increase in activity and performance when used as electrodes in electrochemical environments. The BDD thin films (~200-500 nm) were deposited using microwave plasma assisted chemical vapor deposition (MW PA CVD) onto anodically fabricated TiO2...
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Emission profile of butan-2-one oxime from commercially available neutral silicone sealant
PublicationThe paper presents results of research on emission profile of butan-2-one oxime (methyl ethyl ketoxime, MEKO) released from two types of commercially available neutral silicone sealants: silicone type ‘S’ and silicone type ‘T’. To determine the emissions from silicone samples, the system consists of a stationary emission chamber, and the thermal desorption-gas chromatography-mass spectrometry system was applied. First, the research...
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Melanoma skin cancer detection using mask-RCNN with modified GRU model
PublicationIntroduction: Melanoma Skin Cancer (MSC) is a type of cancer in the human body; therefore, early disease diagnosis is essential for reducing the mortality rate. However, dermoscopic image analysis poses challenges due to factors such as color illumination, light reflections, and the varying sizes and shapes of lesions. To overcome these challenges, an automated framework is proposed in this manuscript. Methods: Initially, dermoscopic...
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Time window based features extraction from temperature modulated gas sensors for prediction of ammonia concentration
PublicationElectronic gas recognition systems, in literature commonly referred as electronic noses, enable the recognition of a type and a concentration of various volatile compounds. Typical electronic gas-analyzing device consists of four main elements, namely, gas delivery subsystem, an array of gas sensors, data acquisition and power supply circuits and data analysis software. The commercially available metal-oxide TGS sensors are widely...
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ADAPTATION OF THE ACTIVATED SLUDGE TO THE DIGESTATE LIQUORS DURING THE NITRIFICATION AND DENITRIFICATION PROCESSES
PublicationThe activated sludge process of the digestate liquors after chemical separation was conducted using a 10 L lab-scale sequencing batch reactor (SBR) and a 0.50 m3 pilotscale SBR independently (with pH control). Due to the relatively high concentration of free ammonia (FA), clear inhibitory effects of the digestate liquors on the nitrifying bacteria were observed. The adaptation of the activated sludge to the toxicity was evaluated...
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Facile formation of self-organized TiO2 nanotubes in electrolyte containing ionic liquid - ethylammonium nitrate and their remarkable photocatalytic properties
PublicationThe oriented TiO2 nanotube arrays (NTs) are identified as a stable, active and recyclable photocatalytic surface. However, their photoactivity is strictly depended on morphology (especially length), which could be controlled by anodic oxidation parameters, including electrolyte properties. To control the morphology, were successfully synthesized a series of NTs by a novel approach where ionic liquid (IL), ethylammonium nitrate...
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The Influence of Microstructure on the Passive Layer Chemistry and Corrosion Resistance for Some Titanium-Based Alloys
PublicationThe effect of microstructure and chemistry on the kinetics of passive layer growth and passivity breakdown of some Ti-based alloys, namely Ti-6Al-4V, Ti-6Al-7Nb and TC21 alloys, was studied. The rate of pitting corrosion was evaluated using cyclic polarization measurements. Chronoamperometry was applied to assess the passive layer growth kinetics and breakdown. Microstructure influence on the uniform corrosion rate of these alloys...
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Electrochemical degradation of textile dyes in a flow reactor: effect of operating conditions and dyes chemical structure
PublicationIn this study, electrochemical oxidation of five azo dyestuffs (Yellow D-5GN, Red D-B8, Ruby F-2B, Blue D-5RN, Black DN), that are widely used in the textile industry, was investigated in a flow reactor. BDD electrode with a high boron doping level (C/B = 10 000) was prepared and used. Two configurations of reactor were considered, i.e., one with the undivided cell, and the other with the cell divided by anodic and cathodic compartments....
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Role of the disulfide bond in stabilizing and folding of the fimbrial protein DraE from uropathogenic Escherichia coli
PublicationDr fimbriae are homopolymeric adhesive organelles of uropathogenic Escherichia coli composed of DraE subunits, responsible for the attachment to host cells. These structures are characterized by enormously high stability resulting from the structural properties of an Ig-like fold of DraE. One feature of DraE and other fimbrial subunits that makes them peculiar among Ig-like domain-containing proteins is a conserved disulfide bond...
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The miniaturised emission chamber system and home-made passive flux sampler studies of monoaromatic hydrocarbons emissions from selected commercially-available floor coverings
PublicationThe estimation of the emission rate of organic compounds released from various types of indoor materials can be performed using stationary environmental test chambers (ETC) classified as ex-situ methods or small-scale portable analytical devices based on the use of passive technique at the stage of analytes sampling from the gaseous phase (in-situ methods). The paper presents results of emissions of selected organic compounds from...
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Flow maldistribution and its mitigation in mini heat exchangers
PublicationIn the present paper, a detailed numerical investigation has been carried out to analyze the flow maldistribution in 50 parallel 1 mm x 1 mm rectangular minichannels and 1 mm depth minigap section with rectangular, trapezoidal, triangular or concave mani-folds in Z-type flow configuration (16 different cases). The working medium was ethanol and the mass flow rate was 5×10-4 kg/s. Both sections was heated from the bottom side. Heat...
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One Europe, one product, two prices - the price disparity in the EU
PublicationThe price dispersion in the European Union in the last fifteen years (1990-2005) is analysed. The analysis of price convergence is examined on aggregate and disaggregate levels. The macro approach is based on Comparative Price Level index calculated as the ratio between PPPs and exchange rate. The disaggregate analysis utilizesactual prices of 148 individual products sold in the 15 capital cities of the EU. The calculations comprise...
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The multivariate multilevel analisis of different regional factors impact on road saferty in european country regions = Wielopoziomowa analiza wieloczynnikowa wpływu różnych charakterystyk regionalnych na poziom bezpieczeństwo ruchu w regionach krajów europejskich
PublicationIn this research, the effect of the European regional differences on the risk of been killed in road accident in these regions is investigated. Factors which differentiate regions can be described as automotive, economic, infrastructural, demographic, geographic. Analyzed risk, counted as regional fatality rate was modeled by the Poisson model. Because of regional diversity of Poisson distribution parameters, the Poisson distribution...
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Comparison of Tracking Methods in Respect of Automation of Animal Behavioral Test
PublicationAutomation in experiments carried out on animals is getting more and more important in research. Computers take over laborious and time-consuming activities like recording and analysing images of experiment scene. The first step in an image analysis is finding and distinguishing between the observed animals, and then tracking all objects during the experiment. In this paper four tracking methods are presented. Quantitative and...
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On noncausal weighted least squares identification of nonstationary stochastic systems
PublicationIn this paper, we consider the problem of noncausal identification of nonstationary, linear stochastic systems, i.e., identification based on prerecorded input/output data. We show how several competing weighted (windowed) least squares parameter smoothers, differing in memory settings, can be combined together to yield a better and more reliable smoothing algorithm. The resulting parallel estimation scheme automatically adjusts...
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On noncausal identification of nonstationary stochastic systems
PublicationIn this paper we consider the problem of noncausal identification of nonstationary,linear stochastic systems, i.e., identification based on prerecorded input/output data. We show how several competing weighted least squares parameter smoothers, differing in memory settings, can be combined together to yield a better and more reliable smoothing algorithm. The resulting parallel estimation scheme automatically adjusts its smoothing...
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Red Algae – An Alternative Source of Carbon Material for Energy Storage Application
PublicationNew electrode material obtained by pyrolysis of aquatic biomass macro (red algae) soaked with glucose solution has been characterized by SEM, EDX and Raman spectroscopy. Graphitized carbon was identified by Raman spectroscopy. Galvanostatic cyclic polarization of the materials in contact with 1M LiPF6 electrolyte in EC:DMC (1:1 v/v) and Li as a counter electrode was performed. Specific capacity of the novel material was enhanced...
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Limiting distribution of Lempel Ziv'78 redundancy
PublicationWe show that the Lempel Ziv'78 redundancy rate tends to a Gaussian distribution for memoryless sources. We accomplish it by extending findings from our 1995 paper [3]. We present a new simplified proof of the Central Limit Theorem for the number of phrases in the LZ'78 algorithm. As in our 1995 paper, here we first analyze the asymptotic behavior of the total path length in a digital search tree (a DST) built from independent sequences....
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On the Limiting distribution of Lempel Ziv'78 Redundancy for Memoryles Sources
PublicationWe show that the Lempel Ziv'78 redundancy rate tends to a Gaussian distribution for memoryless sources. We accomplish it by extending findings from our 1995 paper [3]. We present a new simplified proof of the Central Limit Theorem for the number of phrases in the LZ'78 algorithm. As in our 1995 paper, here we first analyze the asymptotic behavior of the total path length in a digital search tree (a DST) built from independent sequences....
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Discussion of “Development of an Accurate Time integration Technique for the Assessment of Q-Based versus h-Based Formulations of the Diffusion Wave Equation for Flow Routing” by K. Hasanvand, M.R. Hashemi and M.J. Abedini
PublicationThe discusser read the original with great interest. It seems, however, that some aspects of the original paper need additional comments. The authors of the original paper discuss the accuracy of a numerical solution of the diffusion wave equation formulated with respect to different state variables. The analysis focuses on nonlinear equations in the form of a single transport equation with the discharge Q (volumetric flow rate)...
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Study of the Effect of Filling Thermoplastic Medical Polyurethane with PVA, PLA or Diatomite on the Relaxation Times Distributions of 1H NMR
PublicationIn this work, to characterize the mobility of diferent sections of the macromole‑ cules of polyurethane (PUR), polyvinyl alcohol (PVA), and polylactic acid (PLA), as well as the density of crosslinks of the polymer chains when using fllers, we used the distributions of spin–lattice and spin–spin relaxation times for the protons. It is shown that the rigidity of the thermoplastic polymers depends on the sizes of the granules of...
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GENERALISED HERSCHEL MODEL APPLIED TO BLOOD FLOW MODELLING
PublicationThis paper introduces a new rheological model of blood as a certain generalisation of the standard Herschel-Bulkley model. This model is a rheological constitutive equation and belongs to the group of the so-called generalised Newtonian fluids. Experimental data is compared with results, obtained from the new model, to demonstrate that it allows for the best agreement together with Luo-Kuang model. The new model may be easily implemented...
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Reliable underwater communication system for shallow coastal waters
PublicationThis paper presents a reliable and robust low data rate spread spectrum approach which is implemented in the acoustic underwater communication system for shallow coastal waters. It shows operation assumptions of spread spectrum techniques based on the wellknown Shannon equation. It describes two methods of spread spectrum: frequency hopping spread spectrum and direct sequence spread spectrum; their block diagram and their characteristics...
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Turmeric nanofiber-encapsulated natural product formulation act as a phytogenic feed additive—A study in broilers on growth performance, biochemical indices of blood, and E. coli in cecum
PublicationA phytogenic feed additive (PFA) formulation was prepared with bioactive molecules—curcuminoids, gingerol, and carvacrol by encapsulating in nanofiber isolated from turmeric spent (turmeric nanofiber, TNF). This formulation was completely characterized by scanning electron microscope, ultra performance liquid chromatography, and gas chromatography and evaluated for its efficacy. PFA-encapsulated TNF (PFA@TNF) considerably increased...
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New data acquisition system for birch sap concentrate production using the reverse osmosis technology
PublicationThe work presents a simple electronic device that helps to monitor the basic parameters of the reverse osmosis (RO) system during the concentration of birch tree sap. The construction costs are low (around 150 Euro) but the functionality of the device is high. It has an in-build two channel conductometer and can measure the volumetric flow rate of two streams of liquids. The collected data are transmitted wirelessly via Bluetooth...
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Kinetics of nitrogen removal processes in constructed wetlands
PublicationThe aim of this paper is to present a state-of-the-art review of the kinetics of nitrogen removal in constructed wetlands. Biological processes of nitrogen removal from wastewater can be described using equations and kinetic models. Hence, these kinetic models which have been developed and evaluated allow for predicting the removal of nitrogen in treatment wetlands. One of the most important, first order removal model, which is...
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Tolerance-Aware Optimization of Microwave Circuits by Means of Principal Directions and Domain-Restricted Metamodels
PublicationPractical microwave design is most often carried out in the nominal sense. Yet, in some cases, performance degradation due to uncertainties may lead to the system failing to meet the prescribed specifications. Reliable uncertainty quantification (UQ) is therefore important yet intricate from numerical standpoint, especially when the circuit at hand is to be evaluated using electromagnetic (EM) simulation tools. Tolerance-aware...
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Antenna Optimization Using Machine Learning with Reduced-Dimensionality Surrogates
PublicationIn modern times, antenna design has become more demanding than ever. The escalating requirements for performance and functionality drive the development of intricately structured antennas, where parameters must be meticulously adjusted to achieve peak performance. Often, global adjustments to geometry are necessary for optimal results. However, direct manipulation of antenna responses evaluated with full-wave electromagnetic (EM)...
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Monitoring strategy for industrially contaminated rivers - A study of all year round behaviour of Klodnica river catchment, upper Silesia, Poland
PublicationThe study was undertaken to thoroughly characterise the contamination of water in industrially influenced river Klodnica, in order to explore monitoring strategies in case of limited analytical capacity. Statistical analysis undertaken after a short study was found to be helpful in reducing monitoring efforts in the future.Klodnica river is located within area of dominating coal mining, metallurgy, and additionally being influenced...
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Molecular Dynamics to Predict Cryo-EM: Capturing Transitions and Short-Lived Conformational States of Biomolecules
PublicationSingle-particle cryogenic electron microscopy (cryo-EM) has revolutionized the field of the structural biology, providing an access to the atomic resolution structures of large biomolecular complexes in their near-native environment. Today’s cryo-EM maps can frequently reach the atomic-level resolution, while often containing a range of resolutions, with conformationally variable regions obtained at 6 Å or worse. Low resolution...
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Rapid multi-objective optimization of antennas using nested kriging surrogates and single-fidelity EM simulation models
PublicationEver increasing performance requirements make the design of contemporary antenna systems a complex and multi-stage process. One of the challenges, pertinent to the emerging application areas but also some of the recent trends (miniaturization, demands for multi-functionality, etc.), is the necessity of handling several performance figures such as impedance matching, gain, or axial ratio, often over multiple frequency bands. The...
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Preliminary Identification of Quantitative Factors Determining the Duration of Court Proceedings in Commercial Cases
PublicationPurpose: The aim of the article was to identify factors that are linear combinations of the variables under scrutiny that affect the duration of court proceedings. Design/Methodology/Approach: This research was conducted on commercial cases, based on the Principal Components Analysis (PCA). The original variables were grouped into factors that are correlated with each other. The Kaiser Criterion (own value >1) was chosen as the...
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Validated HPTLC method for determination of ledol and alloaromadendrene in the essential oil fractions of Rhododendron tomentosum plants and in vitro cultures and bioautography for their activity screening
PublicationRhododendron tomentosum (Ledum palustre) is a bog shrub used in traditional medicine for treatment of respiratory and rheumatic diseases. Due to the large variability of the chemical composition of its essential oil, depending on the habitat, the in vitro cultures were established as the alternative source of the volatile fraction. There is a need to monitor a quality of the field grown as well as in vitro plant material, especially...
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Nondestructive global corrosion measurement using guided wavefield data
PublicationMetallic structures often face degradation, and corrosion ranks among the most prevalent forms of deterioration. Accurate quantification of corrosion is crucial, especially for structures exposed to harsh environmental conditions, such as marine vessels and offshore installations. Because the traditional measurement methods based on scanning by ultrasonic gauge are time-consuming and provide only rough information on the thickness...
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Rapid Antenna Optimization with Restricted Sensitivity Updates by Automated Dominant Direction Identification
PublicationMeticulous tuning of geometry parameters turns pivotal in improving performance of antenna systems. It is more and more often realized using formal optimization methods, which is demonstrably the most efficient way of handling multiple design variables, objectives, and constraints. Although in some cases a need for launching global search arises, a typical design scenario only requires local optimization, especially when a decent...
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The effect of thermal modification on the quality of the milled surface of beech and pine wood
PublicationThe article deals with the effect of thermal modification on the quality of the created surface during milling on CNC milling cutters. The quality of the created surface is evaluated based on surface roughness, specifically its roughness parameter Ra. The observed surface is created by a shank cutter with a diameter of 20 mm and three cutting edges in a spiral at a standard speed of 18,000. min-1. The article compares thermally...
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Historical carpentry corner log joints—Numerical analysis within stochastic framework
PublicationThe paper presents the results of numerical analysis performed on historical, traditional carpentry corner logjoints of two basic topologies: the short-corner dovetail connection and the saddle notch connection. These types of carpentry joints are commonly used in currently preserved objects of wooden architecture. All connections have been modelled in pinewood, which has been defined in the Finite Element software MSC.Marc/Mentat...
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Inhomogeneity of low-noise wearing courses evaluated by tire/road noise measurements using the close-proximity method
PublicationPerforming numerous analyses of tire/road noise measurements on low-noise pavements during the last several years, the authors observed significant inhomogeneity of the wearing course in numerous cases, while similar problems were almost non-existent when dense pavements were measured. Three main causes of low-noise pavement inhomogeneity can be defined. The first one is imperfections in the technology used for asphalt mix production...
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Efficient Calibration of Cost-Efficient Particulate Matter Sensors Using Machine Learning and Time-Series Alignment
PublicationAtmospheric particulate matter (PM) poses a significant threat to human health, infiltrating the lungs and brain and leading to severe issues such as heart and lung diseases, cancer, and premature death. The main sources of PM pollution are vehicular and industrial emissions, construction and agricultural activities, and natural phenomena such as wildfires. Research underscores the absence of a safe threshold for particulate exposure,...
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Quantum randomness protected against detection loophole attacks
PublicationDevice and semi-device-independent private quantum randomness generators are crucial for applications requiring private randomness. However, they are vulnerable to detection inefficiency attacks and this limits severely their usage for practical purposes. Here, we present a method for protecting semi-device-independent private quantum randomness generators in prepare-and-measure scenarios against detection inefficiency attacks....
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Performance evaluation and model-based optimization of the mainstream deammonification in an integrated fixed-film activated sludge reactor
PublicationThis study aimed to model and optimize mainstream deammonification in an integrated fixed-film activated sludge (IFAS) pilot plant under natural seasonal temperature variations. The effect of gradually decreasing temperature on the performance was evaluated during a winter season and a transition period to summer conditions, and the correlation of the performance parameters was investigated using principal component analysis (PCA)....
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A FPTAS for minimizing total completion time in a single machine time-dependent scheduling problem
PublicationIn this paper a single machine time-dependent scheduling problem with total completion time criterion is considered. There are given n jobs J1,…,Jn and the processing time pi of the ith job is given by pi=a+bisi, where si is the starting time of the ith job (i=1,…,n),bi is its deterioration rate and a is the common base processing time. If all jobs have deterioration rates different and not smaller than a certain constant u>0,...
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Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines. Part II. Unsteady processes
PublicationThe second part of the article presents the results of operating diagnostic tests of a two- and three-shaft engine with a separate power turbine during the start-up and acceleration of the rotor units. Attention was paid to key importance of the correctness of operation of the automatic engine load control system, the input for which, among other signals, is the rate of increase of the exhaust gas flow temperature. The article...
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Extremophile Deinococcus geothermalis as potential source of proteolytic enzymes
PublicationAmong many extremozymes, thermophilic enzymes have attracted most attention during the past four decades. Such enzymes are of considerable industrial and biotechnological interest due to the fact that the enzymes are better suited for harsh industrial processes. There are many advantages of conducting industrial processes at high temperature, such as the increased solubility of many polymeric substrates, resulting in decreased...
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A digital implementation of the PSK transmitter and receiver as multirate algorithms of the digital signal processing
PublicationIn this paper designs of the transmitter and the receiver of PSK signals as three-rate algorithms of the digital signal processing are described. Additionally we show the examples of the transmitter and the receiver of the following signals: BPSK, QPSK. We discussed also an influence of the cascade of the shaping filter and the receiving filter on the intersymbol interference in the received complex envelope.W pracy opisano projektowanie...
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Parametric method for evaluating optimal ship deadweight
PublicationThe paper presents a method of choosing the optimal value of the cargo ships deadweight. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper ship for a given transportation task. The deadweight is determined on the basis of a selected economic measure of the transport effectiveness of ship – the Required Freight Rate (RFR). The...
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Effect of microstructure on mechanical properties of BA1055 bronze castings
PublicationThe article presents research results performed on aluminum bronze CuAl10Fe5Ni5 (BA1032) castings used for marine propellers. Metallographic studies were made on light microscope and a scanning electron microscope to assess quantitatively and qualitatively the alloy microstructure. It has been shown that the shape, size and distribution of the iron-rich phase precipitates in bronze microstructure significantly affect its mechanical...
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The selected effects of high temperature air-steam mixture wood drying
PublicationThe results of properties change of beech wood after drying process are presented. The wood taken to experiments was from northern part of Pomeranian region in Poland. Before the main high temperature drying process using air-steam mixture, wood was initially dried in an open air conditions. The high temperature drying process was conducted at temperature 120oC, humidity 48%, flow rate of drying medium 2.5m/s and atmospheric pressure....