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Wyniki wyszukiwania dla: FEED SPEED
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Preliminary studies on the effect of feed speed on the colour change of wood
PublikacjaThis paper presents the results of preliminary analyses of the effect of cutting parameters on changes in the colour of wood. Beech wood cut with use circular saw was analysed. The cutting parameter tested was the feed speed, represented by the feed per tooth. Sawing processes with different feed per tooth ranging from 0.0008 mm to 0.09 mm were analysed. It was observed that over the entire range of feed rate per tooth analysed,...
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Effect of pine impregnation and feed speed on sound level and cutting power in wood sawing
PublikacjaThe sound levels along with the cutting power registered during the sawing process of the impregnated and non-impregnated pine wood at two feed speeds are shown and compared in this paper. Statistically significant differences in the acoustic signals occurred at the lower feed rate. The differences became smaller with an increase in the feed speed. In contrast to the sound signal, the differences...
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Theoretical and Actual Feed Per Tooth During Wood Sawing on an Optimizing Cross-Cut Saw
PublikacjaThe work presents the geometries of circular saw teeth, whose task is to divide the cross-cut of the cutting layer. For efficient machining on a cross-cut saw with high feed speed values (about 1 ms−1) maximal theoretical feeds per tooth are determined. These values were compared with the actual values determined during transverse cutting of pine wood on a special test stands in industrial conditions. In the experiment the rotational...
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Jumping Wave 2D Profiles
Dane BadawczeThe file contains 2D profiles obtained from a jumping wave study in front of the tool during burnishing of 1.0562 steel by the toroidal-cone tool. Burnishing speed 30.5 m/min, feed of burnishing 0.2mm/rev Force 550 and 800 N.
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The influence of feed rate and shear forces on the devulcanization process of ground tire rubber (GTR) conducted in a co-rotating twin screw extruder
PublikacjaThe search for new ways to recycling of rubber waste has been the aim of many studies conducted by research centers and companiesworldwide. The results of our investigations on the process of continuous thermomechanical devulcanization of ground tire rubber using a twin screw extruder are presented.We used a co-rotating twin screw extruder with a special configuration of plasticizing unit, enabling generation of considerable shear...
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SEM examination of surface layer of C45 steel after grinding on defferent depth
Dane BadawczeFerrite examination for the medium carbon structural steel with low content of Mn, Si, Cu, Cr and Ni after its grinding to a depth of 2 µm, 8 µm, 14 µm and 20 µm, at constant wheel circumferential speed of vs = 25 m/s and constant feed rate vft = 1 m/min. It was shown that the grinding of C45 steel causes strong work hardening of ferrite in surface...
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Vibration surveillance for efficient milling of flexible details fixed in adjustable stiffness holder
PublikacjaThe paper presents the results of research related to the possibility of using an intelligent workpiece holder with adjustable stiffness, during end milling process. Machining a one side supported flexible workpiece will be performed with constant spindle speed and feed speed. In order to avoid hazardous vibration, stiffness of the especially designed spring (mounted in a workpiece holder) will be modified off-line. In order to...
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Use of response surface methodology in characterization of properties of recycled high density polyethylene/ground tire rubber compositions
PublikacjaSearching for newways to utilize rubber and polymerwaste has been the focus of many studies conducted by research centers and companies worldwide. In this study, the influence of extrusion conditions on the properties of thermoplastic compositions containing post-production recycled high density polyethylene (PE-HD) and ground tire rubber (GTR) at 50:50 mass ratiowas examined. Response Surface Methodology (RSM) was used to determine...
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The methodology for determining of the value of cutting power for cross cutting on optimizing sawing machine
PublikacjaIn the article the methodology of forecasting the energy effects of the cross-cutting process using the classical method, which takes into account the specific cutting resistance, is presented. The values of cutting power for the cross-cutting process of two types of wood (softwood and hardwood) were forecasted for the optimizing sawing machine with using presented methodology. The cross-cutting process with high values of feed...
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Vibration Surveillance System with Variable Stiffness Holder for Milling Flexible Details
PublikacjaEfficient milling of the flexible details (i.e. rotor blades, thin-walled elements) using slender ball-end tools is a difficult task due to possibility of vibration occurrence. Because of the existence of certain conditions (small depths of cutting, regeneration phenomena), cutting process may lose stability and self-excited chatter vibration may appear. Frequency of the chatter vibration is close to dominant natural frequency...
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Modelling and Simulation of a New Variable Stiffness Holder for Milling of Flexible Details
PublikacjaModern industry expectations in terms of milling operations often demand the milling of the flexible details by using slender ball-end tools. This is a difficult task because of possible vibration occurrence. Due to existence of certain conditions (small depths of cutting, regeneration phenomena), cutting process may become unstable and self-excited chatter vibration may appear. Frequency of the chatter vibration is close to dominant...
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Analysis of Denoising Autoencoder Properties Through Misspelling Correction Task
PublikacjaThe paper analyzes some properties of denoising autoencoders using the problem of misspellings correction as an exemplary task. We evaluate the capacity of the network in its classical feed-forward form. We also propose a modification to the output layer of the net, which we called multi-softmax. Experiments show that the model trained with this output layer outperforms traditional network both in learning time and accuracy. We...
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Charakterystyka procesu ciągłej dewulkanizacji termomechanicznej z zastosowaniem metod doświadczalnych
PublikacjaBadano proces termomechanicznej dewulkanizacji rozdrobnionych odpadów gumowych prowadzono przy użyciu wytłaczarki dwuślimakowej współbieżnej o specjalnej konfiguracji układu uplastyczniającej, umożliwiającego wywieranie znacznych sił ścinających na miał gumowy. W badaniach doświadczalnych zastosowano metodę powierzchni odpowiedzi RSM (response surface methodology). Wyznaczono modele matematyczne wyrażające zmienność właściwości...
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Study of a Multicriterion Decision-Making Approach to the MQL Turning of AISI 304 Steel Using Hybrid Nanocutting Fluid
PublikacjaThe enormous use of cutting fluid in machining leads to an increase in machining costs, along with different health hazards. Cutting fluid can be used efficiently using the MQL (minimum quantity lubrication) method, which aids in improving the machining performance. This paper contains multiple responses, namely, force, surface roughness, and temperature, so there arises a need for a multicriteria optimization technique. Therefore,...
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The Influence of the Depth of Cut in Single-Pass Grinding on the Microstructure and Properties of the C45 Steel Surface Layer
PublikacjaThe paper contains the results of a metallographic examination and nanoindentation test conducted for the medium carbon structural steel with low content of Mn, Si, Cu, Cr, and Ni after its grinding to a depth ranging from 2 μm to 20 μm, at constant cutting speed (peripheral speed) of vs = 25 ms−1 and constant feed rate of vft = 1 m/min. Applied grinding parameters did not cause the surface layer hardening, which could generate...
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Statistical analysis and robust design of circularly polarized antennas using sequential approximate optimization
PublikacjaIn the paper, reliable yield estimation and tolerance-aware design optimization of circular polarization (CP) antennas is discussed. We exploit auxiliary kriging interpolation models established in the vicinity of the nominal design in order to speed up the process of statistical analysis of the antenna structure at hand. Sequential approximate optimization is then applied to carry out robust design of the antenna, here, oriented...
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Fracture Toughness and Shear Yield Strength Determination for Two Selected Species of Central European Provenance
PublikacjaWhen offcut of wood is formed by shearing, Atkins’s analyses of sawing processes can be applied. Using this modern approach, it is possible to determine the fracture toughness and shear yield strength of wood. This model is only applicable for the axial-perpendicular cutting direction because both of these parameters are suitable for the given direction of cutting edge movement and cannot be considered material constants. Alternatively,...
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On Alternative Approaches to Design of Corporate Feeds for Low-Sidelobe Microstrip Linear Arrays
PublikacjaTwo design approaches, illustrated by simulations and measurements, aiming at a systematic computer-aided design of printed circuit feeds for low-sidelobe microstrip antenna arrays are described. The novelty of these approaches resides in identification of the optimal feed architectures with subsequent simulation-based optimization of the feed and array aperture dimensions. In this work, we consider microstrip corporate feeds realizing...
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A rapid dispersive liquid–liquid microextraction of antimicrobial onion organosulfur compounds in animal feed coupled to gas chromatography-mass spectrometry
PublikacjaA rapid analytical procedure is proposed for determining two antimicrobial onion organosulfur compounds, propyl disulfide (PDS) and propyl propane thiosulfonate (PTSO), in animal feed. The use of PTSO as a natural ingredient in animal feed is allowed due to its antimicrobial activity against pathogenic organisms. Two analytical methodologies using gas chromatography coupled to mass spectrometry (GC-MS) are compared. After the extraction...
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Cleaner energy for sustainable future using hybrid photovoltaics-thermoelectric generators system under non-static conditions using machine learning based control technique
PublikacjaIn addition to the load demand, the temperature difference between the hot and cold sides of the thermoelectric generator (TEG) module determines the output power for thermoelectric generator systems. Maximum power point tracking (MPPT) control is needed to track the optimal global power point as operating conditions change. The growing use of electricity and the decline in the use of fossil fuels have sparked interest in photovoltaic-TEG...
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Effect of Laminar Pulsatile Fluid Flow on Separation of Volatile Organic Compounds from Aqueous Solution by a Hollow Fiber Membrane-Based Process
PublikacjaIn this study, a laminar pulsatile fluid flow was used for the separation of benzene, toluene, ethylbenzene, and xylene isomers (BTEX) from aqueous solutions. Polyether sulfone hollow fiber membrane has been applied to this process. The effects of BTEX concentration, and feed and extraction flow rates were examined. It was found that the application of the pulsatile fluid flow with...
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Effect of operating conditions on N 2 O production in an anammox sequencing batch reactor containing granular sludge
PublikacjaNitrous oxide (N2O) is one of the gases with the greatest impact in the atmosphere due to its persistence and significant contribution to the greenhouse effect. This study provides an insight into the dynamics of N2O production in wastewater nitrogen removal systems. A 10 L sequencing batch reactor containing enriched anammox biomass was subjected to different operational conditions, i.e., temperature, feed time, NO2 /NH4 þ ratio...
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Thermochemical Conversion of Biomass and Municipal Waste into Useful Energy Using Advanced HiTAG/HiTSG Technology
PublikacjaAn advanced thermal conversion system involving high-temperature gasification of biomass and municipal waste into biofuel, syngas or hydrogen-rich gas is presented in this paper. The decomposition of solid biomass and wastes by gasification is carried out experimentally with a modern and innovative regenerator and updraft continuous gasifier, among others. A ceramic high-cycle regenerator provides extra energy for the thermal conversion...
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The Influence of Low-Temperature Disintegration on the Co-Fermentation Process of Distillation Residue and Waste-Activated Sludge
Publikacja: Innovative low-temperature disintegration (process temperature 55 ◦C and oxygen concentration 0.2 mg/dm3 ) can be an economically rational technology to intensifying energy production from renewable sources. The proposed process can achieve a degree of disintegration—under optimal conditions—of about 50%, which is excellent when compared with other methods of feed pre-treatment. The low-temperature disintegration of distillation...
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Copolymerization of Styrene and Pentadecylphenylmethacrylate (PDPMA): Synthesis, Characterization, Thermomechanical and Adhesion Properties
PublikacjaThe copolymerization of styrene (St) with a bioderived monomer, pentadecylphenylmethacrylate (PDPMA), via atom transfer radical polymerization (ATRP) was studied in this work.The copolymerization reactivity ratio was calculated using the composition data obtained from1HNMR spectroscopy, applying Kelen-Tudos and Finemann-Ross methods. The reactivity ratio of styrene (r1=0.93) and PDPMA (r2=0.05) suggested random copolymerization...
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Topological modifications for performance improvement and size reduction of wideband antenna structures
PublikacjaCompact antennas belong to the key components of modern communication systems. Their miniaturization is often achieved by introducing appropriate topological changes such as simple ground plane slots or tapered feeds. More sophisticated modifications are rarely considered in the literature because they normally lead to significant increase of the number of tunable parameters, which makes the antenna design process more challenging....
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Simple design criteria and efficiency of hydrodynamic vortex separators
PublikacjaVortex separators are locally applied for waste water treatment in different systems - from storm waste water sewerage to water treatment in fish ponds. However, the methods for separator design presented in the literature are questionable. The paper presents two simple and functional criteria that were employed to construct a laboratory test stand. The test results gave positive feed back on the efficiency of vortex separators.
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Mercury concentrations in marine biota with special focus on grey and ringed seals
PublikacjaMarine organisms are exposed and sensitive to effects of environmental contamination by heavy metals including different forms of mercury. Baltic seals as the top predators of the marine ecosystem are even more endangered due to (considerable) longevity as well as a long biological half-time of toxin elimination. The concentrations of mercury in seals from the Baltic is poorly known, thus the aim of this work is to determine and...
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The possibility of use keratin products in various branches of industry
PublikacjaBird's feather, the main by-product of the poultry industry, are not enough utilized and negatively influencing the environment. They contain large amount of keratin, the protein with high cystine content. The aim of our work was to obtain hydrolysates and isolates of keratin, which can be used in various areas of food, cosmetics, pharmaceutical industry and as animal feed. Keratin can be hydrolyzed and extracted from feather after...
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Design optimization of novel compact circular polarization antenna
PublikacjaThe paper describes a structure and a design optimization procedure of a miniaturized circular polarization antenna with elliptical ground plane slots and feed line with stepped-impedance stubs. Constrained optimization of all antenna parameters is executed in order to explicitly reduce the antenna size while maintaining required impedance axial ratio bandwidth of 5 GHz to 7 GHz at the same time. The size of the optimized antenna...
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Bioactive and bioavailability of minerals in rats loaded with cholesterol and kiwi fruit
PublikacjaThe aim of this study was to compare the content of polyphenols (TP), minerals, ascorbic acid (AA) and total antioxidant capacities (TAC) of conventional and organic kiwifruit ‘Hayward’ treated with ethylene after harvest and to determine their influence on plasma TAC, mineral content in the liver and bioavailability (RBV — relative bioavailability value) in rats fed diet containing cholesterol. Organic and conventionally grown...
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Design of microstrip antenna subarrays: a simulation-driven surrogate-based approach
PublikacjaA methodology for computationally efficient simulation-driven design of microstrip antenna subarrays is presented. Our approach takes into account the effect of the feed (here, a corporate network) on the subarray side-lobe level and allows adjustment of both radiation and reflection responses of the structure under design within a single automated process. This process is realized as surrogate-based optimization that produces...
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Simulation-Driven Design of Microstrip Antenna Subarrays
PublikacjaA methodology for computationally efficient simulation-driven design of microstrip antenna subarrays is presented. Our approach takes into account the effect of the feed (e.g., a corporate network) on the subarray side lobe level and allows adjusting both radiation and reflection responses of the structure under design within a single automated process. This process is realized as surrogate-based optimization that produces designs...
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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
PublikacjaA 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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The Possibility to use a Nuclear Power Plant as a Source of Electrical Energy and Heat
PublikacjaIn this article issues concernig the possibility of nuclear power plant (NPP) operation also as a source of heat, which means combined heat and power production, have been described. CHP work is possible and profitable only in those areas where high thermal power demand occurs, which means near city agglomerations such as Warsaw or the Tri-City. Two levels of thermal power delivered to the heating system have been considered. Preliminary...
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Utilization of ionic liquids for the enrichment of biogas
PublikacjaThis article discusses the dependence of biogas composition on organic feed material. High amounts of CO2 decrease the calorific value of biogas. Several technologies are reviewed which can be used to increase the calorific value. Special emphasis is laid on ionic liquids as a new absorbing material. ILs have a number of advantages due to their unique properties such as: low melting point, high thermal conductivity, no flammability,...
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Laboratory bioreactor with pH control system for investigations of hydrogen production in the dark fermentation process
PublikacjaThe work presents the construction of a low-cost research bioreactor equipped with a pH control sys-tem. The developed bioreactor was applied for hydrogen production in the dark fermentation process using Enterobacter aerogenes ATCC 13048. Presented paper compares the results obtained during the process without and with pH regulation for different feed materials: glucose, energetic poplar hydro-lysates, acid whey and glycerol....
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Estimation of Broadband Complex Permeability Using SIW Cavity-Based Multimodal Approach
PublikacjaIn this article, an attractive multimodal substrate integrated waveguide (SIW) based methodology is presented for the characterization of magnetic materials in the broadband microwave frequency. The proposed approach employs a modified feed under-coupled SIW cavity instead of conventional feed over-coupled multiple SIW cavities; it uses the modified closedform expression, developed from the first principle to consider the effect...
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AN INNOVATIVE APPROACH TO PREDICTION ENERGETIC EFFECTS OF WOOD CUTTING PROCESS WITH CIRCULAR-SAW BLADES
PublikacjaIn the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. The aim of the paper is to present a new calculating model using the application of modern fracture mechanics and to compare cutting parameters of native beech, Bendywood...
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Low-Loss Mechanically Tunable Resonator and Phase Shifters in Groove Gap Waveguide Technology
PublikacjaThis research is focused on the design and realization of high-performance high-power variable phase shifters in groove gap waveguide technology. Specifically, it is shown that the unique characteristic of groove gap waveguides, which is its proper operation without the need for electrical connection between the top and bottom sections of the waveguide, can be used to design mechanically tunable devices. Using the proposed method,...
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Influence of drying mode and feed per tooth rate on the fine dust creation in pine and beech sawing on a mini sash gang saw
PublikacjaThe experimental results of the study focused on the effect of drying processes of modified air drying and warm air steam mixture drying of pine and beech wood on the size of sawdust particles created in cutting using PRW-15M sash gang saw, are presented in the paper. Particle size analysis of dry sawdust was performed using two methods—sieving method and laser diffraction analysis. The results showed that the drying process did...
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Design and optimization of a novel compact broadband linearly/circularly polarized wide-slot antenna for WLAN and Wi-MAX applications
PublikacjaA novel topologically modified structure of a compact low profile wide-slot antenna for broadband applications is presented. The antenna comprises a modified E-shaped slot with unequal arm lengths in the ground plane, and a parasitic quasi-rectangular loop placed coplanar with the feedline. For exciting orthogonal modes with equal amplitude, a single-point feeding technique with an asymmetrical geometry of the coplanar waveguide...
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Analysis of 2D Feature Spaces for Deep Learning-based Speech Recognition
Publikacjaconvolutional neural network (CNN) which is a class of deep, feed-forward artificial neural network. We decided to analyze audio signal feature maps, namely spectrograms, linear and Mel-scale cepstrograms, and chromagrams. The choice was made upon the fact that CNN performs well in 2D data-oriented processing contexts. Feature maps were employed in the Lithuanian word recognition task. The spectral analysis led to the highest word...
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Unity-Gain Zero-Offset CMOS Buffer with Improved Feedforward Path
PublikacjaA voltage unity-gain zero-offset CMOS amplifier with reduced gain error and increased PSRR (power supply rejection ratio) is proposed. The amplifier uses two feed mechanisms, negative feedback and supporting positive feedforward, to achieve low deviation from unit gain over the entire input range. The circuit, designed in a standard 180-nanometer 1.8-voltage CMOS process, is compared with two known buffers of similar topology,...
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Design and Optimization of a Compact Planar Radiator for UWB Applications and Beyond
PublikacjaA compact monopole antenna for ultra-wideband (UWB) and beyond applications has been proposed. The radiator is based on the monopole topology. The super-wideband behavior has been achieved using a combination of spline-based modifications applied to the driven element, as well as utilization of a tapered feed and a slot-modified ground plane. The electrical performance of the structure has been tuned using a numerical optimization...
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Neural networks and deep learning
PublikacjaIn this chapter we will provide the general and fundamental background related to Neural Networks and Deep Learning techniques. Specifically, we divide the fundamentals of deep learning in three parts, the first one introduces Deep Feed Forward Networks and the main training algorithms in the context of optimization. The second part covers Convolutional Neural Networks (CNN) and discusses their main advantages and shortcomings...
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Pervaporation of volatile organohalogen compounds throughpolydimethylsiloxane membrane
PublikacjaThe objective of this work was to apply dense polymeric membranes for pervaporation of tetrachloroethene from aqueous solution. Three membranes were evaluated: polydimethylsiloxane (PDMS-PV1 and PDMSPV2) membranes, and a PDMS with ZSM-5 zeolite filled (PERVAP-1070) membrane. The effect of feed composition on flux and selectivity was also investigated. Tested membranes showed good properties in the separation of tetrachloroethylene,...
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Servo tracking of targets at sea
PublikacjaW artykule przedstawiono propozycje systemu sterowania układem śledzącym umieszczonym na okręcie. Przedstawiono dynamikę błędów śledzenia obiektu we współrzędnych LOS (ang., Line - Of - Sight). Zostało wykazane, że regulacja błędów śledzenia LOS jest możliwa przy pomocy sprzężenia feed-forward od prędkości śledzonego obiektu. Ponieważ prędkość ta nie jest mierzalna zastosowano filtr Kalmana w celu jej estymacji. Ponieważ problem...
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Circularly Polarized Antenna Array design with the Potential of Gain-Size Trade-off and Omnidirectional Radiation for Millimeter-Wave Small Base Station Applications
PublikacjaThis paper presents the design and validation of a slot-patch-hybrid circularly polarized antenna array for 28 GHz millimeter (mm) wave (mm-wave) applications. The proposed design has a simple geometry that facilitates the fabrication process, which is otherwise a challenging task due to the sub-mm dimensions of the circuit in the mm-wave band. In the proposed structure, aperture-coupled series slot-fed array is utilized to excite...
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Morphology and local chain structure of polyamide 6 modified in the solid state with a semi-aromatic nylon salt
PublikacjaStructural and conformational differences between the polyamide 6 (PA6) homopolymer and two copolymers of PA6 modified in the solid state with 20 and 30 wt% of the semi-aromatic nylon salt of 1,5-diamino-2-methylpentane (Dytek A) and isophthalic acid (IPA) in the feed were investigated. Room temperature wide-angle X-ray diffraction (WAXD) analysis together with 13C{1H} cross-polarization/magic-angle spinning solid-state (CP/MAS)...