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Mixed conductivity in tungstenite-phosphate glasses containing alkali metal ions
PublikacjaThe conductivity of glasses in the 50WO3-(50-x)P2O5-xA2O (A = Na, K, Cs) system has been investigated as a function of composition. It is shown that in tungstenite-phosphate glasses containing different alkali metal ions the conductivity decreases with an increase in the alkali metal ion content. A decrease in conductivity is larger for heavier ions and reaches more than seven orders of magnitude in the case of glass containing...
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Employment and export specialisation along the development path: some robust evidence
PublikacjaThis paper contributes to the literature on the evolution of overall specialisation along the process of economic development by simultaneously estimating 'specialisation curves' emerging from fully comparable employment and export statistics in a sample of 32 economies (1980-2000). We apply semiparametric estimation methods, which allow us to combine the flexibility of the estimation with the inclusion of country-specific effects,...
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Dynamics of mechanical model of implant-tissue system in ventral hernia repair
PublikacjaThe paper deals with a finite element modelling of implants in the problem of ventral hernia repair. The synthetic mesh implanted in the abdomen during surgery is here modelled as a membrane structure. Thesystem undergoes the internal abdominal pressure that occurs during the postoperative cough, the load identified in the literature as the main cause of the connection failure and hernia recurrence. The model can be used to estimate...
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An Objective Focussing Measure for Acoustically Obtained Image
PublikacjaIn scientific literature many parameters of an image sharpness can be defined, that can be used for the evaluation of display energy concentration (EC). This paper proposes a new, simple approach to EC quantitative evaluation in spectrograms, which are used for the analysis and visualization of sonar signals. The presented approach of the global-image EC measure was developed to the evaluation of EC in arbitrary direction (or at...
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Power converter interface for urban DC traction substations - solutions and functionality.
PublikacjaThis paper focuses on extending an urban DC traction substation functionality by means of an additional power converter interface (PCI). In particular, by enabling bidirectional energy exchange between LV DC traction grid, AC grid and V2G chargers. Among other things, the presented material compares general attributes of the most promising DC/DC converters that can be used in a PCI, meet the requirements of galvanic isolation and...
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Review and Indication of Key Activities for Energy Management Improvement in DC Microgrids
PublikacjaDC MicroGrids (MG) must have Energy Management Systems (EMS) to guarantee efficient, dependable, and environmentally friendly electricity. The application of Model Predictive Control (MPC), proved to be helpful due to its adaptability and capacity to use non-linear models. This paper, based on an extensive literature review, identifies and discusses the three key activities to improve the characteristics of DC microgrids, i.e.:...
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Control system for contactless electrical energy transfer with varying air gap
PublikacjaInductive power transfer (IPT) is a system by which electrical energy may be transmitted without electrical connection through a large air gap between coils. Systems usually considered in the literature are the ones with a constant air gap. The paper describes the analysis of IPT, which allows for supplying an electrical load in the conditions of slow, in relation to the dynamics of power supply, changes in the dimensions of the...
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An assessment of teeth quality of the mini gang saw blade
PublikacjaIn this work, the assessment of the effect of the operating time (90 min.) of the mini gang saw blades during sawing Scotch pine (Pinus sylvestris L.) samples upon changes of the saw blade teeth sharpness (bluntness), which was defined as an effective radius of the nose ρ , has been described. The research activities have been carried out on the Nikon Ti-S optical microscope equipped with the Nikon DS-30W camera allowing high-speed...
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On the correlation between magnetoacoustic emission and magnetostriction dependence on the applied magnetic field
PublikacjaThe correlation between magnetoacoustic emission signal envelopes and magnetostriction curves is investigated. Two sets of samples are being considered: tempered martensitic steel and plastically deformed ferritic steel. It is shown that even though some general relations may be observed, as was demonstrated in the literature, the correlation is not always present. One may not expect to change both quantities in the same way if...
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On power stream in motor or drive system
PublikacjaIn a motor or in a drive system the quantity of power increases in the direction opposite to the direction of power flow. Energy losses and energy efficiency of a motor or a drive system must be presented as functions of physical quantities independent of losses. Such quantities are speed and load. But the picture of power stream in a motor or in a drive system is presented in the literature in the form of traditional Sankey...
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Heat transfer in plate heat exchanger channels: experimental validation of selected correlation equations
PublikacjaThis study is focused on experimental investigation of selected type of brazed plate heat exchanger. The Wilson approach was applied in order to estimate heat transfer coefficients for the PHEx passages. The main aim of the paper was to experimentally check ability of several correlations published in the literature to predict heat transfer coefficients by comparison experimentally obtained data with appropriate predictions. The...
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Revision of Biological Methods for Determination of EDC Presence and Their Endocrine Potential
PublikacjaEndocrine-disrupting compounds (EDC) are chemicals responsible for disturbances in the hormonal balance of organisms. This group of chemicals includes both egzogenic and endogenic substances or their mixtures that impact functioning of natural hormones in organisms. In the available literature one can find information on the application of chromatographic and related techniques in the analysis of environmental samples for detection,...
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TOXICOLOGICAL ASSESSMENT OF FOOD PACKAGES EXTRACTS
PublikacjaIn the scientific literature related to the widely understood issue of packaging materials designed to have contact with food (Food Contact Materials – FCM) there is much information on raw materials used for their production, their physiochemical properties, types and parameters. There is also a great number of publications on the management and disposal of used packaging. Unfortunately, not much attention is given to the matters...
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Multiacces quantum communication and product higher rank numerical range
PublikacjaIn the present paper we initiate the study of the product higher rank numerical range. The latter, being a variant of the higher rank numerical range, is a natural tool for study- ing a construction of quantum error correction codes for multiple access channels. We review properties of this set and relate it to other numerical ranges, which were recently introduced in the literature. Further, the concept is applied to the construction...
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Piezo 2011, Electroceramics for End-Users VI
PublikacjaThis work extends a power harvesting with using piezoelectric materials. Experimental presents the development of a piezoelectric MEMS generator which has the ability to scavenge mechanical energy of ambient vibrations from their surroundings and transform it into electrical energy that can be used in energy storage applications. Recent literature shows that piezoelectric transduction has received the most attention for vibration-to-electricity...
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Inlet air fogging of marine gas turbine in power output loss compensation
PublikacjaThe use of inlet air fogging installation to boost the power for gas turbine engines is widely applied in the power generation sector. The application of fogging to mechanical drive is rarely considered in the literature [1]. This paper will cover some considerations relating to its application to gas turbines in ship drive. There is an important evaporative cooling potential throughout the world when the dynamic data is evaluated,...
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INFLUENCE OF A VERTEX REMOVING ON THE CONNECTED DOMINATION NUMBER – APPLICATION TO AD-HOC WIRELESS NETWORKS
PublikacjaA minimum connected dominating set (MCDS) can be used as virtual backbone in ad-hoc wireless networks for efficient routing and broadcasting tasks. To find the MCDS is an NP- complete problem even in unit disk graphs. Many suboptimal algorithms are reported in the literature to find the MCDS using local information instead to use global network knowledge, achieving an important reduction in complexity. Since a wireless network...
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Evaluating Business Accelerator Participants’ Experiences – Effectuation at Play?
PublikacjaResponding to the new phenomena in entrepreneurship ecosystems in Poland, the author undertakes the study that aims to explore experiences of participants of (pre)accelerator programme for start-ups. Clipster is a business an acceleration incubation programme, where participants have a unique co-living opportunity and work on their new venture ideas. With phenomenological interviews with six nascent entrepreneurs - participants...
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Evaluating Business Accelerator Participants’ Experiences – Effectuation at Play?
PublikacjaResponding to the new phenomena in entrepreneurship ecosystems in Poland, the author undertakes the study that aims to explore experiences of participants of (pre)accelerator programme for start-ups. Clipster is a business an acceleration and incubation programme, where participants have a unique co-living opportunity and work on their new venture ideas. With phenomenological interviews with six nascent entrepreneurs - participants...
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Sample preparation and recent trends in volatolomics for diagnosing gastrointestinal diseases
PublikacjaThe analysis of the human volatilome can be successfully used for rapid and non-invasive diagnostics of gastrointestinal diseases. However, the introduction of techniques based on detection of volatiles is limited, among other factors, by difficulties which arise during the sampling stage and instrumental analysis. The aim of this article was to review and discuss medical and analytical literature on the analysis of volatiles in...
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The Use of Vegetables in the Biomonitoring of Cadmium and Lead Pollution in the Environment
PublikacjaLead and cadmium emitted from various anthropogenic sources have the ability to accumulate in tissues of living organisms. The phenomenon of accumulation of metals in the body is harmful and undesirable. On the other hand, the ability of plants to accumulate heavy metals from the individual elements of the environment has been used in biomonitoring of pollution. Leaf and root of vegetables have particular predisposition for accumulating...
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TOTAL SHIP OPERABILITY – REVIEW, CONCEPT AND CRITERIA
PublikacjaThe ship operability can be understood and analysed in different manners, and its quality is described using different indexes by different authors. Practically, there is no general and widely accepted description of total ship operability in the literature, nor in the rules of classification societies, which would include both seakeeping and manoeuvrability characteristics of a ship, and simultaneously take into account all ship...
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Effect of band gap on power conversion efficiency of single-junction semiconductor photovoltaic cells under white light phosphor-based LED illumination
PublikacjaOn the basis of the detailed balance principle, curves of efficiency limit of single-junction photovoltaic cells at warm and cool white light phosphor-based LED bulbs with luminous efficacy exceeding 100 lm/W have been simulated. The effect of energy band gap and illuminance on the efficiencies at warm and cool light is discussed. The simulations carried out show that maximum power conversion efficiency at 1000 lx reaches 52.0%...
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Heat transfer in plate heat exchanger channels: experimental validation of selected correlation equations
PublikacjaThis study is focused on experimental investigation of selected type of brazed plate heat exchanger. The Wilson approach was applied in order to estimate heat transfer coefficients for the PHEx passages. The main aim of the paper was to experimentally check ability of several correlations published in the literature to predict heat transfer coefficients by comparison experimentally obtained data with appropriate predictions. The...
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The Taxonomy Spatial Measure of Development in the Standard of Living Analysis
PublikacjaIncorporation of spatial relationships in the construction of taxonomy measure of development is gaining popularity in Polish literature. However, there is no one common idea concerning how the spatial relationship should be taken into account when creating a synthetic variable nor, indeed, where the spatial weight matrix should be placed. It seems that the inclusion of spatial relationships is more important in smaller regions’...
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Effect of Sinusoidal Corrugated Geometries on the Vibrational Response of Viscoelastic Nanoplates
PublikacjaThe vibrational behavior of viscoelastic nanoplates with a corrugated geometry is a key topic of practical interest. This problem is addressed here for wrinkled nanoplates with small corrugations related to incorrect manufacturing. To this end, a new One-Variable First-order Shear Deformation plate Theory (OVFSDT) is proposed in a combined form with a non-local strain gradient theory. The Kelvin–Voigt model is employed to describe...
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Energy Efficiency and Economic Policy: Comprehensive Theoretical, Empirical, and Policy Review
PublikacjaIn this paper, we analyze the role of economic policy in prompting energy efficiency. This study reviews three aspects, theoretical, empirical, and existing policies to evaluate the relationship of energy efficiency and economic policy. This study furthermore identifies the existing issues from a policy perspective in energy efficiency. Although not all public policies may be justified, it suggests that these types of financial...
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A derivatisation agent selection guide
PublikacjaThe development of new tools for providing high quality information in a cost-effective and expeditious way is one of the main aims of analytical chemistry. Remarkably, the introduc- tion of the 12 principles of green chemistry paved the way forward for the development of analytical methodologies that are, ideally, inherently safe for the operator and the environ- ment, with the least possible consumption of energy and chemicals,...
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[soft skills] Scientific databases and information skills
Kursy Online{mlang pl} Dyscyplina: wszystkie dyscypliny Zajęcia obowiązkowe dla doktorantów I roku Prowadzący: Liczba godzin: 5 Forma zajęć: wykład {mlang} {mlang en} Discipline: all disciplines Obligatory course for 1st-year PhD students Academic teacher: Total hours of training: 5 teaching hours Course type: lecture {mlang} Soft skills Area II - researcher's workshop "Scientific databases and information skills" The training...
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AUTOMATYCZNA KLASYFIKACJA MOWY PATOLOGICZNEJ
PublikacjaAplikacja przedstawiona w niniejszym rozdziale służy do automatycznego wykrywania mowy patologicznej na podstawie bazy nagrań. W pierwszej kolejności przedstawiono założenia leżące u podstaw przeprowadzonych badan wraz z wyborem bazy mowy patologicznej. Zaprezentowano również zastosowane algorytmy oraz cechy sygnału mowy, które pozwalają odróżnić mowę niezaburzoną od mowy patologicznej. Wytrenowane sieci neuronowe zostały następnie...
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ANALIZA BIBLIOMETRYCZNA BADAŃ NAD KONKURENCYJNOŚCIĄ MIĘDZYNARODOWĄ
PublikacjaCelem artykułu jest prezentacja wyników metaanalizy prac naukowych z zakresu międzynarodowej konkurencyjności, opublikowanych w ciągu ostatnich siedemdziesięciu lat w bazach ISI Web of Science oraz EconLit. W analizie wykorzystane zostały podstawowe metody bibliometryczne przy wsparciu oprogramowania HistCite. Przeprowadzona analiza umożliwiła ocenę w czasie rozwoju badań nad międzynarodową konkurencyjnością oraz identyfikację...
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Kształtowanie wartości wskaźników płynności finansowej przez przedsiębiorstwa z sektora MSP w zależności od osiąganej rentowności aktywów
PublikacjaW artykule przedstawiono różnice w sposobie kształtowania wartości wskaźników z obszaru płynności finansowej pomiędzy przedsiębiorstwami z sektora MSP w zależności od osiąganego przez nie poziomu rentowności aktywów. W trakcie przeprowadzonych badań uwzględniono 109 174 sprawozdania finansowe przedsiębiorstw, prowadzących działalność gospodarczą w 27 różnych działach gospodarki narodowej. Do potwierdzenia zróżnicowania płynności...
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Wartości rekomendowane wskaźników sprawności działania dla przedsiębiorstw z sektora MSP
PublikacjaNiniejszy artykuł poświęcony jest zagadnieniu sprawności działania małych i średnich przedsiębiorstw. W trakcie przeprowadzonych badań wykorzystano 34 820 sprawozdania finansowe przedsiębiorstw. Dla potwierdzenia zróżnicowania sprawności działania w zależności od przynależności sektorowej przedsiębiorstwa wykorzystano test nieparametryczny Kruskala – Wallisa. Zawarte w artykule wyniki badań dowodzą, że MSP należące do różnych działów...
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Nowatorskie podejście do zarządzania jakością w branży morskiej na przykładzie stoczni Ostróda Yacht
PublikacjaArtykuł opisuje podejście procesowe funkcjonujące w jednej z największych polskich stoczni jachtowych Ostróda Yacht. Stocznia ta stanowi ilustrację – zakończonej z sukcesem – implementacji narzędzi Lean Production i stanowi przykład dla innych przedsiębiorstw w Polsce. Celem niniejszej publikacji jest ukazanie nowatorskiego podejścia do zarządzania jakością w stoczni jachtowej, które przyniosło korzyści zarówno z poziomu zarządzania...
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Szyby zespolone w systemach fasadowych
PublikacjaW artykule przedstawiono wybrane kryteria techniczne stosowane do oceny jakościowej izolacyjnych szyb zespolonych. Bazując na własnych doświadczeniach, autor zwrócił uwagę na pojawiające się problemy w trakcie odbiorów technicznych na budowie. Przedstawiono także krótki przegląd literatury z zakresu szkła budowlanego i szyb zespolonych.
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O projektowaniu ściany szczelinowej
PublikacjaW pracy przedstawiono proces weryfikacji i porównania obliczeń otrzymanych z programu bazującego na metodzie elementów skończonych z wynikami analitycznymi dla analizowanej ściany szczelinowej z przyporą ziemną. Dodatkowo autorzy dokonali krótkiego przeglądu literatury z zakresu ścian szczelinowych.
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Adaptive Wavelet-Based Correction of Non-Anechoic Antenna Measurements
PublikacjaNon-anechoic measurements represent an affordable alternative to evaluation of antenna performance in expensive, dedicated facilities. Due to interferences and noise from external sources of EM radiation, far-field results obtained in non-ideal conditions require additional post-processing. Conventional correction algorithms rely on manual tuning of parameters, which make them unsuitable for reliable testing of prototypes. In this...
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Rebuilding Bailey Bridge to Bridge With Bascule Span – A Case Study
PublikacjaThe structural analysis of a road foldable prefabricated steel Bailey- type bridge located over the Tuga River in Żelichowo, Poland is performed in this paper. Interesting and untypical bridge redevelopment performed made it possible to lift the middle foldable bridge span by approximately 4.0 m concerning the existing state. The paper begins with a survey of literature carried out on the investigations of foldable Bailey-type...
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Automatic Correction of Non-Anechoic Antenna Measurements using Low-Pass Filters
PublikacjaPrototype measurements belong to key steps in the development of antenna structures. They are normally performed in expensive facilities, such as anechoic chambers (ACs). Alternatively, antenna performance can be extracted (at a low cost) in non-anechoic conditions upon appropriate post-processing. Unfortunately, existing correction algorithms are difficult to set up and prone to failure, which limits their practical usefulness....
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Correlation between structural and electrical properties in highly porous (Y,Sr)(Ti,Nb)O3-delta SOFC anodes
PublikacjaIn order to find a relationship between structural and electrical properties, niobium and yttrium doped SrTiO3 ceramics were prepared via solid-state reaction. The samples were sintered in hydrogen and air conditions. The samples were also fabricated with a pore-former to obtain highly porous specimens. The electrical properties of Nb-doped SrTiO3 samples and yttrium and niobium co-doped SrTiO3 were compared. The comparable electrical...
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On the hat problem, its variations, and their applications
PublikacjaThe topic of our paper is the hat problem in which each of n players is randomly fitted with a blue or red hat. Then everybody can try to guess simultaneously his own hat color by looking at the hat colors of the other players. The team wins if at least one player guesses his hat color correctly, and no one guesses his hat color wrong; otherwise the team loses. The aim is to maximize the probability of a win. There are known many...
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Internationalization of Born Globals from Theoretical Perspective
PublikacjaThe paper discusses the evolution of theoretical approaches towards internationalisation process of firms, especially SMEs. It clarifies the definitions of born global (BG) firm, presents its characteristics and the specifics of its internationalisation process. The objective of this paper is to present internationalisation process of born global firm from theoretical perspective. The article starts with presentation of the oldest...
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The criteria for evaluation and selection the best tender applied by the authorities in Poland and selected EU countries
PublikacjaThe aim of the regulation in EU countries concerning public procurement is to ensure efficient spending of funds by evaluating and choosing the most advantageous offer. The aim of the conducted research is to determine the extent the Polish contracting entities benefit from the possibility of broad selection of various criteria for tender evaluation. On the basis of the analysis of 500 notices on work procedures conducted in the...
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Chemical and Mechanical Properties of 70-Year-Old Concrete
PublikacjaThe aim of this research is to determine the durability and strength of concrete continuous footing based on the chosen mechanical, physical, and chemical properties of the concrete. The presented investigations constitute some opinions from experts on the bearing capacity of concrete continuous footing and the possibilities of carrying additional loads and extended working life. The cylindrical specimens were taken from continuous...
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Inter-governmental Collaborative Networks for Digital Government Innovation Transfer -Structure, Membership, Operation
PublikacjaDigital government refers to the transformation of government organizations and their relationships with citizens, business and each other through digital technology. It entails digital innovation in processes, services, organizations, policies, etc. which are increasingly developed and tested in one country and transferred, after adaptation, to other countries. The process of innovation transfer and the underlying information...
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A New Geodetic Method of Examination of Geometrical Conditions of a Crane Bridge
PublikacjaSafety is one of the key aspects related to crane-based material transport. In order to ensure safe crane operation and material transport, it is necessary to meet certain geometrical conditions. The authors addressed the geometrical conditions of a crane bridge, a substantial crane component. The paper presents the method to compute displacement components of points on the top of a bridge crane relative to their design position....
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Water uptake in protective organic coatings and its reflection in measured coating impedance
PublikacjaWater uptake in commercially available epoxy coating on mild steel using impedance spectroscopy and gravimetry was studied. The water content in the coating was determined using the Brasher-Kingsbury equation and various methods of coating capacitance calculation used in the literature. The obtained results were compared with reference gravimetric data. An overestimation of values obtained from impedance data in relation to gravimetric...
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Accuracy of Differential Phase Delay Estimation for GPS Spoofing Detection
PublikacjaGPS spoofing is an attack based on transmission of false signals to target receivers, in order to force the computation of incorrect time, position or velocity information. It is a threat which is recently considered with continuously growing awareness. There is a need for effective way of GPS spoofing detection. Many groups of methods are proposed in the literature. Spatial processing methods are considered to be robust in a wide...
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Legal destructive entrepreneurship in the modern economy
PublikacjaMotivation: Usually examples of activities that have a positive impact on the economy of the state are cited. Destructive entrepreneurship refers to activities that have negative impact on the economy. This phenomenon is relatively new in the literature and does not yet have a precise definition. Aim: The aim of this article is to attempt a definition of the phenomenon of legal destructive entrepreneurship. The author also analysed...
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THE INFLUENCE OF THE EVOLUTION OF DAYLIGHTING SYSTEMS OF EXHIBITION SPACE ON THE ARCHITECTURE OF THE MUSEUM'S BUILDING
PublikacjaThe paper deals with the architecture of museums as dependent on the ways of lighting the exhibition space. The work focuses on the analysis of the influence of daylighting systems on shaping the museum's architecture in the period from the Renaissance to modern times. The method of work includes studying literature and the case study of the objects characteristic of the presented concepts and lighting systems. The results of the...