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Wyniki wyszukiwania dla: abandonment ratio
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Technological vs. Non-Technological Mindsets: Learning From Mistakes, and Organizational Change Adaptability to Remote Work
PublikacjaThe permanent implementation of the change in working methods, e.g., working in the virtual space, is problematic for some employees and, as a result, for management leaders. To explore this issue deeper, this study assumes that mindset type: technological vs. non-technological, may influence the organizational adaptability to change. Moreover, the key interest of this research is how non-technological mindsets...
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Performance evaluation and model-based optimization of the mainstream deammonification in an integrated fixed-film activated sludge reactor
PublikacjaThis 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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Relationship between wages, labour productivity and unemployment rate in new EU member countries
PublikacjaThe main aim of this article is to find out the extent to which relative labour productivity and relative unemployment rate changes determine relative wage changes. We use average annual macro-data for the period 2002-2013 for Poland and other 5 new EU members: Estonia, Hungary, Slovak, Czech Republic and Slovenia. Using Poland as benchmark, rst we examine the correlation between wage, productivity and unemployment rate changes...
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Property-performance relationship of core-shell structured black TiO2 photocatalyst for environmental remediation
PublikacjaUnderstanding the relationship between the properties and performance of black titanium dioxide with core-shell structure (CSBT) for environmental remediation is crucial for improving its prospects in practical applications. In this study, CSBT was synthesized using a glycerol-assisted sol-gel approach. The effect of different water-to-glycerol ratios (W:G = 1:0, 9:1, 2:1, and 1:1) on the semiconducting and physicochemical properties...
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Deep compaction control of sandy soils
PublikacjaVibroflotation, vibratory compaction, micro-blasting or heavy tamping are typical improvement methods for the cohesionless deposits of high thickness. The complex mechanism of deep soil compaction is related to void ratio decrease with grain rearrangements, lateral stress increase, prestressing effect of certain number of load cycles, water pressure dissipation, aging and other effects. Calibration chamber based interpretation...
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Al(III) and Cu(II) simultaneous foam separation: Physicochemical problems
PublikacjaSimultaneous removal of Al(III) and Cu(II) from dilute aqueous solutions by ion and precipitate flotation methods is investigated. Influence of the pH of the initial solution, the surface active collector concentration and the gas flow rate on the final removal ratio and the course of ion and precipitate flotations is presented. Results show that simultaneous flotations of Al(OH)3 and Cu(OH)2 insoluble species occur allowing to...
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On the tendency of temperature and electric field dependences of interface recombination in P3HT:PCBM organic bulk heterojunction solar cells
PublikacjaWe demonstrate theoretical explanation of the temperature and electric field dependences of recombination coefficients in an organic P3HT:PCBM bulk heterojunction solar cell. Based onthe model of interface recombination, two analytical formulas describing the relative ratio of the interface (γI ) to the Langevin (γL) recombination coefficients have been derived. Our analysis indicates that the sign of parameters φT and φF determines...
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A decision-making system supporting selection of commanded outputs for a ship's propulsion system with a controllable pitch propeller
PublikacjaThe ship's operators have to make decisions regarding the values of commanded outputs (commanded engine speed and pitch ratio) which ensure maximum vessel speed and minimum fuel consumption. Obviously, the presented decision problems are opposed. Therefore, there is a need for a compromise solution that enables more flexible vessel voyage planning. This paper deals with development of a computer-aided system supporting selection...
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Anisotropic mechanical behavior and auxeticity of penta-graphene: Molecular statics/molecular dynamics studies
PublikacjaWe investigate the mechanical properties of penta-graphene (PG), a recently proposed two-dimensional carbon allotrope using atomistic simulation techniques combined with the empirical description of interatomic interactions. We report on the dependence of its three in-plane mechanical moduli (i.e. Young's modulus, Poisson's ratio and shear modulus) on the deformation direction, strain and temperature. We show that PG displays a...
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COMPARISON OF INVESTMENT PERFORMANCE MEASURES USING THE EXAMPLE OF SELECTED STOCK EXCHANGES
PublikacjaIn the following paper, the main objective is to examine whether the selection of the performance measure influences the evaluation of individual investments and the performance rankings generated on that basis. This study presents the values of 16 performance indicators along with their detailed descriptions. All calculations were made using the R program, and the source code can be found at the end of the article. Nine selected...
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CFD Simulations and Tests of a Prototype Flow Control Valve
PublikacjaIn this paper a prototype of a flow control valve is described and numerically simulated. The flow control valve is used in hydraulic systems to maintain constant fluid flow despite changing loads of a receiver. The standard construction of this type of valves is modified mainly by eliminating the spring. The prototype consists the hydrostatically unloaded throttle valve and pressure ratio valve substituting pressure difference...
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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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Struktura źródeł finansowania ponadprzeciętnie rentownych przedsiębiorstw z sektora MSP
PublikacjaCelem artykułu jest przedstawienie w przekroju sektorowym kształtowania struktury finansowania przez MSP uzyskujące ponadprzeciętnie wysoką rentowność aktywów. W trakcie przeprowadzonych badań uwzględniono 109 174 sprawozdań finansowych przedsiębiorstw prowadzących działalność gospodarczą w 27 różnych działach gospodarki narodowej. Sektorowe zróżnicowanie wartości wskaźników struktury źródeł finansowania zostało potwierdzone przy...
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Identyfikacja parametrów dynamicznych want mostu Rędzińskiego we Wrocławiu
Publikacjathe paper presents results of dynamic analysis conducted on stay-cables of rędziński bridge in wrocław. identified in situ dynamic parameters (natural frequency and logarithmic decrement damping ratio) of selected stays were and compared to the values featured in the project.
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Experimental study on effectiveness of polymer dampers in reduction of structural vibrations
PublikacjaVibrations of civil engineering structures, generated by dynamic loads, may be very dangerous to the structures themselves as well as may have significant influence on human perception and comfort. A number of different methods have been proposed in order to minimize such situations. This concern newly designed structures as well as those which dynamic properties have to be modified due to problems with excessive vibrations. One...
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Synthesis and characterization of biopolyols through biomass liquefaction of wood shavings and their application in the preparation of polyurethane wood composites
PublikacjaThe sustainability of production systems in wood processing, wood industry, and wooden waste disposal is an important issue for European industry and society. Proper development of products based on renewable wood resources gives an opportunity to provide materials with long-term environmental, social, and economic sustainability. This study aims to establish a new way of forestry and agricultural waste materials utilization by...
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Structure-property relationships in peroxide-assisted blends of poly(ε-caprolactone) and poly(3-hydroxybutyrate)
PublikacjaPoly(ε-caprolactone) and poly(3-hydroxybutyrate) (PCL/PHB) blends in two weight ratios (75/25 and 50/50) were reactively compatibilized in the presence of di-(2-tert-butyl-peroxyisopropyl)-benzene and dicumyl peroxide as free radical initiators. Rheological, mechanical, thermal properties and morphological features, as well as the chemical structure of PCL/PHB blends were investigated. It was found that regardless of PCL/PHB blend...
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The changes of crosslink density of polyurethanes synthesised with using recycled component. Chemical structure and mechanical properties investigations.
PublikacjaThis paper aims at the utilisation of glycerolysate (Gly) obtained in polyurethane recycling process by means of crude glycerine, which has in its structure hydroxyl end groups that allow for further processing. Polyurethanes (PUs) were synthesised using prepolymer method with the mixture of neat polyol and glycerolysate, in different ratios, with 4,4-diphenylmethane diisocyanate (MDI). The prepolymer was subsequently extended...
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Experimental study on the effectiveness of polymer dampers in reduction of structural vibrations
PublikacjaVibrations of civil engineering structures, generated by dynamic loads, may be very dangerous to the structures themselves as well as may have significant influence on human perception and comfort. A number of different methods have been proposed in order to minimize such situations. This concern newly designed structures as well as those which dynamic properties have to be modified due to problems with excessive vibrations. One...
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Linear viscoelastic transversely isotropic model based on the spectral decomposition of elasticity tensors
PublikacjaThe linear viscoelasticity is still a useful model in the engineering for studying the behavior of materials loaded with different loading rates (frequencies). Certain types of materials reveal also an anisotropic behavior: fiber reinforced composites, asphalt concrete mixtures, or wood, to name a few. In general, researchers try to identify experimentally the dependence of engineering constants like: directional Young’s moduli...
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A method of the UMTS-FDD network design based on universal load characteristics
PublikacjaIn the paper an original method of the UMTS radio network design was presented. The method is based on simple way of capacity-coverage trade-off estimation for WCDMA/FDD radio interface. This trade-off is estimated by using universal load characteristics and normalized coverage characteristics. The characteristics are useful for any propagation environment as well as for any service performance requirements. The practical applications...
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Cognitive network model dedicated to transport system telematics
PublikacjaThe paper defines the concept of cognitive radio, in the context of transport systems, with particular emphasis on modern ecological concept of “green cognitive radio”. In addition, in the paper a modified cognitive network model dedicated to transport system telematics is proposed and presented. Algorithms to support the functioning of the cognitive radio are discussed. Sensors necessary to use the network to support cognitive...
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Experimental investigation of the PEM fuel cells performance for automotive and stationary applications
PublikacjaThe aim of the study was to provide dynamic characteristics of the PEM fuel cell system consisted of Nexa modules, provide steady-state characteristics of the for different values of air excess ratio and steady-state characteristics for different stack temperatures and given load.
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Współpracować i konkurować w szkolnictwie wyższym – czy to ma sens? Analiza wybranych związków statystycznych
PublikacjaCel: Celem głównym artykułu jest wykazanie, że współpraca i pozycja konkurencyjna uczelni są ze sobą powiązane. Celem szczegółowym jest wykazanie, że sukces, jakim jest uzyskanie finansowania projektu badawczego jest powiązany z poziomem współpracy międzynarodowej konkurujących uczelni, a także z relacją liczby studentów do liczby nauczycieli akademickich. Materiał i metoda: W artykule przyjęto metodę ilościową, której elementem...
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OPROGRAMOWANIE I SPRZĘT W TECHNOLOGII RADIA PROGRAMOWALNEGO
PublikacjaTechnologia radia programowalnego (ang. Software Defined Radio) umożliwia realizację urządzeń pracujących w różnego rodzaju cywilnych i wojskowych systemach radiowych. W pracy zaprezentowano zagadnienia dotyczące koncepcji realizacji radia programowalnego. Zaprezentowano oprogramowanie GNU Radio, służące do realizacji operacji przetwarzania sygnałów w torach nadawczo-odbiorczych urządzeń zrealizowanych w technologii SDR. Przedstawiono...
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Electrochemical behavior of a composite material containing 3D-structured diatom biosilica
Publikacja3D-structured diatom biosilica mixed with conducting carbon black was investigated as an active electrode material for lithium-ion batteries. Diatom biosilica was obtained by cultivation of the selected diatom species under laboratory conditions. Several instrumental techniques (XRD, FTIR, Raman, SEM-EDX, TGA) were used to characterize the physicochemical properties of applied biosilica. It was evidenced that the prepared new composite...
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Flexomagnetic response of buckled piezomagnetic composite nanoplates
PublikacjaIn this paper, the equation governing the buckling of a magnetic composite plate under the influence of an in-plane one-dimensional magnetic field, assuming the concept of flexomagnetic and considering the resulting flexural force and moment, is investigated for the first time by different analytical boundary conditions. To determine the equation governing the stability of the plate, the nonlocal strain gradient theory has been...
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Deep eutectic solvents based assay for extraction and determination of zinc in fish and eel samples using FAAS
PublikacjaA new assay based on effective (high recovery) extraction by means of deep eutectic solvents (DESs) was developed for ppb level determination of zinc in fishes and eel samples. Choline chloride and Phenol in a 1:2 M ratio was selected as optimal DES-based extraction solvent. 8-Hydroxy quinoline was used as a chelating agent for zinc ions. The optimized conditions were found at pH value of 8, ligand concentration of 10 mg/L, THF...
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REALIZACJA INTERFEJSU RADIOWEGO OFDM W TECHNOLOGII RADIA PROGRAMOWALNEGO DO ZASTOSOWAŃ TRANSPORTOWYCH
PublikacjaMetoda wielodostępu OFDM, jest stosowana obecnie w wielu standardach łączności radiowej, w tym w standardzie IEEE802.11p, który jest przewidziany do wykorzystania w Samochodowym Systemie Komunikacji. Technologia radia programowalnego (ang. Software Defined Radio) umożliwia realizacje urządzeń pracujących z tą metodą wielodostępu. W referacie zaprezentowano oprogramowanie GNU Radio i środowisko graficzne GNU Radio Companion służące...
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Application of discrete wavelet transform in seismic nonlinear analysis of soil–structure interaction problems
PublikacjaSimulation of soil-structure interaction (SSI) effects is a time-consuming and costly process. However, ignoring the influence of SSI on structural response may lead to inaccurate results, especially in the case of seismic nonlinear analysis. In this paper, wavelet transform methodology has been utilized for investigation of the seismic response of soil-structure systems. For this purpose, different storey outrigger braced buildings...
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REALIZACJA INTERFEJSU RADIOWEGO OFDM W TECHNOLOGII RADIA PROGRAMOWALNEGO DO ZASTOSOWAŃ WOJSKOWYCH
PublikacjaMetoda wielodostępu OFDM, jest stosowana obecnie w wielu standardach łączności radiowej, w tym w standardzie IEEE802.11p, który jest przewidziany do realizacji transmisji danych pomiędzy pojazdami, oraz pomiędzy pojazdami i infrastrukturą znajdującą się w pobliżu drogi. Technologia radia programowalnego (ang. Software Defined Radio) umożliwia realizacje urządzeń pracujących z tą metodą wielodostępu. W referacie zaprezentowano oprogramowanie...
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Badanie i analiza efektywności alokacji strumieni danych w heterogenicznej sieci WBAN
PublikacjaW niniejszej dysertacji doktorskiej poddano dyskusji efektywność alokacji strumieni danych w heterogenicznej radiowej sieci WBAN (Wireless Body Area Networks). Biorąc pod uwagę dynamiczny rozwój nowoczesnych sieci radiokomunikacyjnych piątej generacji (5G), którego część stanowią radiowe sieci działające w obrębie ciała człowieka, bardzo ważnym aspektem są metody maksymalizujące wykorzystanie dostępnych zasobów czasowo –częstotliwościowych...
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An Empirical Propagation Model for Corridors in Office Buildings
PublikacjaThis paper presents an empirical propagation path loss model for corridors in office buildings. The proposed model estimates changeable character of radio signal attenuation, based on a special approach as a combination of the simple free-space model with the author’s model. The measurement stand and measurement scenario are described. The propagation path loss research have been made in corridor for different frequencies in range...
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Mathematical model defining volumetric losses of hydraulic oil compression in a variable capacity displacement pump
PublikacjaThe objective of the work is to develop the capability of evaluating the volumetric losses of hydraulic oil compression in the working chambers of high pressure variable capacity displacement pump. Volumetric losses of oil compression must be determined as functions of the same parameters, which the volumetric losses due to leakage, resulting from the quality of design solution of the pump, are evaluated as dependent on and also...
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Rotor Blade Geometry Optimisation in Kaplan Turbine
PublikacjaThe paper presents the description of method and results of rotor blade shape optimisation. The rotor blading constitutes a part ofturbine flow path. Optimisation consists in selection of the shape that minimises ratio of polytrophic loss. Shape of the blade isdefined by the mean camber line and thickness of the airfoil. Thickness is distributed around the camber line based on the ratio ofdistribution. Global optimisation was done...
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Numerical Study of Concrete Mesostructure Effect on Lamb Wave Propagation
PublikacjaThe article presents the results of the numerical investigation of Lamb wave propagation in concrete plates while taking into account the complex concrete mesostructure. Several concrete models with randomly distributed aggregates were generated with the use of the Monte Carlo method. The influence of aggregate ratio and particle size on dispersion curves representing Lamb wave modes was analyzed. The results obtained for heterogeneous...
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Improvement of Performance Level of Steel Moment-Resisting Frames Using Tuned Mass Damper System
PublikacjaIn this paper, parameters of the tuned mass dampers are optimized to improve the performance level of steel structures during earthquakes. In this regard, a six-story steel frame is modeled using a concentrated plasticity method. Then, the optimum parameters of the Tuned Mass Damper (TMD) are determined by minimizing the maximum drift ratio of the stories. The performance level of the structure is also forced to be located in a...
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Driver’s Condition Detection System Using Multimodal Imaging and Machine Learning Algorithms
PublikacjaTo this day, driver fatigue remains one of the most significant causes of road accidents. In this paper, a novel way of detecting and monitoring a driver’s physical state has been proposed. The goal of the system was to make use of multimodal imaging from RGB and thermal cameras working simultaneously to monitor the driver’s current condition. A custom dataset was created consisting of thermal and RGB video samples. Acquired data...
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Application analysis of a hybrid solid oxide fuel cell-gas turbine system for marine power plants
PublikacjaThe results of theoretical studies of the possibilities of using hybrid solid oxide fuel cell–gas turbine (SOFC-GT) systems for marine power plants are presented. A 500 kW auxiliary marine power plant scheme using stacks of SOFCs in combination with a regenerative gas turbine operating with over-expansion based on our recent patent application is proposed. The results of mathematical modelling showed the opportunity to obtain a...
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Isolation and some properties of collagen from the backbone of Baltic cod(Gadus morhua)
PublikacjaOssein from Baltic cod backbone was obtained after extraction of non-collagenous protein with 0.1 M NaOH solution and demineralization with 1.0 M HCl solution. The extractions were performed at 4 C for24, 48 and 72 h using a solid/solution ratio from 1:4 to 1:8 (w/v). After 48 h of extraction in 0.5 M acetic acid only about 25% of collagen was dissolved. After 48 h of extraction at optimal concentration of pepsin(4 mg/g ossein)...
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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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Investigations on strength and fracture in RC beams scaled along height or length
PublikacjaThe objective of the present paper is to identify experimentally and theoretically differing failure mechanisms in reinforced concrete beams subjected to four-point bending for a separate variation of the depth and length at the constant thickness. Experiments were performed on reinforced concrete beams under four-point bending. Different failure mechanisms included steel yielding, diagonal tension or shear- compression depending...
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Subjective and Objective Comparative Study of DAB+ Broadcast System
PublikacjaBroadcasting services seek to optimize their use of bandwidth in order to maximize user’s quality of experience. They aim to transmit high-quality digital speech and music signals at the lowest bitrate. They intend to offer the best quality under available conditions. Due to bandwidth limitations, audio quality is in conflict with the number of transmitted radio programs. This paper analyzes whether the quality of real-time digital...
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Downlink Capacity-Coverage Trade-off Estimation Based on Measurement of WCDMA/FDD Interface Load
PublikacjaThe method of capacity-coverage trade-off determination by using of universal load characteristics and normalized coverage curves for the WCDMA/FDD radio interface has been presented. The practical applications of discussed method for UMTS radio network planning process and network exploitation has been mentioned.
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ZRÓŻNICOWANIE STRUKTURY KAPITAŁOWO-MAJĄTKOWEJ W ZALEŻNOŚCI OD WIELKOŚCI PRZEDSIĘBIORSTWA
PublikacjaW artykule przedstawiono różnice w kształtowaniu struktury kapitałowo-majątkowej pomiędzy małymi, średnimi i dużymi przedsiębiorstwami. W trakcie przeprowadzonych badań uwzględniono 97 471 sprawozdań finansowych przedsiębiorstw, prowadzących działalność gospodarczą w 12 różnych działach polskiej gospodarki narodowej. Do potwierdzenia zróżnicowania struktury kapitałowo-majątkowej w zależności od wielkości przedsiębiorstwa wykorzystano...
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Realizacja mobilnego urządzenia do wytwarzania kurtyny elektromagnetycznej do zastosowań specjalnych
PublikacjaIn the article the assumptions, design and realisation of the technological demonstrator of a mobile device for generating an electromagnetic curtain (AEGIS) were presented, both in the area of hardware and software. The device is designed to block radio communication by which it is possible to detonate the Radio Controlled Improvised Explosive Devices (RCIEDs). The preliminary laboratory tests of the demonstrator for generating...
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Elemental composition, environment of deposition of the Lower Carboniferous Emma Fiord Formation oil shale in Arctic Canada
PublikacjaThe sedimentary succession of 51-m consisting of a thin coal seam (1 m) and oil shale with a marlstone and carbonate-mudstone matrix of the Lower Carboniferous (Viséan) Emma Fiord Formation located on the Grinnell Peninsula, Devon Island, Arctic Canada was examined. The techniques used include reflected light microscopy, and instrumental neutron activation analysis (INAA) for elemental concentration, and inductively coupled plasma...
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ZRÓŻNICOWANIE PŁYNNOŚCI FINANSOWEJ W ZALEŻNOŚCI OD WIELKOŚCI PRZEDSIĘBIORSTWA
PublikacjaW artykule przedstawiono różnice w sposobie kształtowania wartości wskaźników z obszaru płynności finansowej pomiędzy małymi, średnimi i dużymi przedsiębiorstwami. W trakcie przeprowadzonych badań uwzględniono 97 471 sprawozdań finansowych przedsiębiorstw, prowadzących działalność gospodarczą w 12 różnych działach polskiej gospodarki narodowej. Do potwierdzenia zróżnicowania płynności finansowej w zależności od wielkości przedsiębiorstwa...
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Zróżnicowanie zadłużenia w zależności od wielkości przedsiębiorstwa
PublikacjaW artykule przedstawiono różnice w sposobie kształtowania wartości wskaźników z obszaru zadłużenia pomiędzy małymi, średnimi i dużymi przedsiębiorstwami. W trakcie przeprowadzonych badań uwzględniono 97 471 sprawozdań finansowych przedsiębiorstw, prowadzących działalność gospodarczą w 12 różnych działach polskiej gospodarki narodowej. Do potwierdzenia zróżnicowania zadłużenia w zależności od wielkości przedsiębiorstwa wykorzystano...
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Collagen type II–hyaluronan interactions – the effect of proline hydroxylation: a molecular dynamics study
PublikacjaHyaluronan–collagen composites have been employed in numerous biomedical applications. Understanding the interactions between hyaluronan and collagen is particularly important in the context of joint cartilage function and the treatment of joint diseases. Many factors affect the affinity of collagen for hyaluronan. One of the important factors is the ratio of 3- or 4-hydroxy proline to proline residues. This article presents...