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Credibility of Threats to Jam Anonymous Traffic Remapping Attacks in Ad Hoc WLANs
PublikacjaIn ad hoc networks, selfish stations can pursue a better quality of service (QoS) by performing traffic remapping attacks (TRAs), i.e., by falsely assigning their traffic to a higher priority class, which can hurt honest stations’ QoS. To discourage the attackers, honest stations can announce their dissatisfaction with the perceived QoS. If such a threat fails, a costly data frame jamming defense can be launched. We analyze the...
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Selektywne zakłócanie transmisji OFDM w interfejsie radiowym NB-IoT
PublikacjaW artykule przedstawiono zagadnienie tzw. inteligentnego zagłuszania, polegającego na selektywnym zakłócaniu krytycznych składowych sygnału OFDM. Opisane zostały badania weryfikujące możliwość przeprowadzenia tego rodzaju ataku elektronicznego. Przedstawiono zrealizowane stanowisko badawcze, umożliwiające zakłócanie rzeczywistych sygnałów NB-IoT w łączu w dół. Wyniki badań wykazują możliwość realizacji selektywnego zagłuszania...
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Assessment of the ice jam potential on regulated rivers and reservoirs with the use of numerical model results
PublikacjaThis study presents an attempt at estimating the jam potential on rivers with significant anthropogenic intervention in the course or flow characteristics of the river. The DynaRiCE model was used for forecasting both the place and time of an ice jam occurrence. In this modified method, two ice parameters are subjected to analysis, namely the relative ice-to-water velocity (vi/vw),and the ice thickness to single floe thickness...
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Numerical modeling of the combustion in a lab-scale pulverized-coal fired combustion chamber
PublikacjaThis work presents results of numerical modeling of the combustion process inside a lab-scale drop-tube chamber, designed to investigate the slagging properties of the flue ashes, created through the solid fuel firing. Interaction between turbulence and chemistry is accounted by use of probability density function (PDF). FLUENT inputs for non-premixed combustion chemistry modeling are defined. A discrete second phase of the coal...
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Numerical modeling of the combustion in a lab-scale pulverized-coal fired combustion chamber
PublikacjaThis work presents results of numerical modeling of the combustion process inside a lab-scale drop-tube chamber, designed to investigate the slagging properties of the flue ashes, created through the solid fuel firing. Interaction between turbulence and chemistry is accounted by use of probability density function (PDF). FLUENT inputs for non-premixed combustion chemistry modeling are defined. A discrete second phase of the coal...
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Torque capacity of multidisc wet clutch with reference to friction occurrence on its spline connections
PublikacjaIn this article developed mathematical model that includes friction occurrence on spline connections is presented. The work also contains results of experimental research on torque capacity of multidisc wet clutch. These results are expressed as a function of contact pressure for different number of friction surfaces. Due to increased interest in research concerning multidisc wet clutches it is essential to determine impact of...
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Exploring the role of social networks among entrepreneurial Polish immigrants
PublikacjaThe paper reports on the explanatory case study among seven Polish enterprising migrants from Aberdeen Scotland. The aim of the paper is to examine role of social support structure and social networks for enterprising Poles. It also attempts to extend of Waldinger et al (2000) ethnic business development model in the context of entrepreneurial strategies taken from by immigrants from their country of origin, claiming that transition...
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DEVELOPMENT OF THE ALGORITHM OF POLISH LANGUAGE FILM REVIEWS PREPROCESSING
PublikacjaThe algorithm and the software for conducting the procedure of Preprocessing of the reviews of films in the Polish language were developed. This algorithm contains the following steps: Text Adaptation Procedure; Procedure of Tokenization; Procedure of Transforming Words into the Byte Format; Part-of-Speech Tagging; Stemming / Lemmatization Procedure; Presentation of Documents in the Vector Form (Vector Space Model) Procedure; Forming...
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FEM ANALYSIS AND EXPERIMENTAL TESTS OF RIGID RISER HANGING SYSTEM
PublikacjaThe article presents the analysis, project, and experimental examination of an original rigid riser for Coil Tubing Pipes. The principle of riser operation is based on the use of friction forces. The research included the FEM analysis of the designed riser, calculations of the required bolt tensions, and checking the effect of the clamping force on stress distribution in the pipeline. The results of computer simulation were verified...
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Sharp transitions in low-number quantum dots Bayesian magnetometry
PublikacjaWe consider Bayesian estimate of static magnetic field, characterized by a prior Gaussian probability distribution, in systems of a few electron quantum dot spins interacting with infinite temperature spin environment via hyperfine interaction. Sudden transitions among optimal states and measurements are observed. Usefulness of measuring occupation levels is shown for all times of the evolution, together with the role of entanglement...
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Human Centric Lighting. The New X Factor?
PublikacjaWe live in challenging times, and one could even claim we’re experiencing a revolution in lighting with LED technology taking over the world. Part of this rapid change involves a concept called Human Centric Lighting (HCL). In Frankfurt this year, during Light+Building, it was the buzzword, with nearly every second manufacturer’s stand claiming they had figured out the special formula necessary to create perfect HCL illumination....
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The Impact of Trade Integration with the European Union on Productivity in a Posttransition Economy: The Case of Polish Manufacturing Sectors
PublikacjaThis paper addresses the relationship between productivity growth in Polish manufacturing sectors and forces stemming from trade integration with the European Union. Empirical analysis (1995-2006) is based on sector-level bilateral data concerning both domestic (Polish) and foreign (partner countries from the enlarged European Union) markets' characteristics and their degree of openness. The main results indicate that, both in...
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Improving automatic surveillance by sound analysis
PublikacjaAn automatic surveillance system, based on event detection in the video image can be improved by implementing algorithms for audio analysis. Dangerous or illegal actions are often connected with distinctive sound events like screams or sudden bursts of energy. A method for detection and classification of alarming sound events is presented. Detection is based on the observation of sudden changes in sound level in distinctive sub-bands...
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Monitoring of Caged Bluefin Tuna Reactions to Ship and Offshore Wind Farm Operational Noises
PublikacjaUnderwater noise has been identified as a relevant pollution affecting marine ecosystems in different ways. Despite the numerous studies performed over the last few decades regarding the adverse effect of underwater noise on marine life, a lack of knowledge and methodological procedures still exists, and results are often tentative or qualitative. A monitoring methodology for the behavioral response of bluefin tuna (Thunnus thynnus)...
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Sonar Pulse Detection Using Chirp Rate Estimation and CFAR Algorithms
PublikacjaThis paper presents a new approach to sonar pulse detection. The method uses chirp rate estimators and algorithms for the adaptive threshold, commonly used in radiolocation. The proposed approach allows detection of pulses of unknown parameters, which may be used in passive hydrolocation or jamming detection in underwater communication. Such an analysis is possible thanks to a new kind of imaging, which presents signal energy in...
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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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ATTEMPT AT EVALUATING THE INFLUENCE OF BENDING STRESS ON SHAFT WEAR PROCESSES IN WATER LUBRICATED SLIDING BEARING WITH A RUBBER BUSHING
PublikacjaWater lubricated bearings find increasingly wide application in shipbuilding or hydro–power industry, the popularity stemming from their numerous advantages. Unfortunately, as it turns out, water lubricated bearings do not always meet expectations, as on occasion they become subject to intense, premature wear which requires costly repair. One of the still unexplained phenomena is the process of excessive bearing wear, in particular...
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Numerical Modeling of Water and Ice Dynamics for Analysis of Flow Around the Kiezmark Bridge Piers
PublikacjaThis paper presents the results of a numerical model study on the effect of ice on the proposed bridge piers in the Vistula River outlet and its effect on flow conditions in the river. The model DynaRICE is used in this study, which is a two-dimensional hydro-ice dynamic numerical model developed for dynamic ice transport and jamming in rivers. To simulate river hydrodynamics in the vicinity of the bridge piers, 2-dimensional numerical...
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Comparative analysis of spectral and cepstral feature extraction techniques for phoneme modelling
PublikacjaPhoneme parameter extraction framework based on spectral and cepstral parameters is proposed. Using this framework, the phoneme signal is divided into frames and Hamming window is used. The performances are evaluated for recognition of Lithuanian vowel and semivowel phonemes. Different feature sets without noise as well as at different level of noise are considered. Two classical machine learning methods (Naive Bayes and Support...
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AEGIS – Mobile Device for Generating Electromagnetic Curtain for Special Applications and Countering the Threats of RCIED
PublikacjaIn the article the assumptions, design and realization of the technological demonstrator of a mobile device for generating an electromagnetic curtain (with a cryptonym AEGIS) were presented, both in the area of hardware and software. The device is designed to block the radio communication systems by which it is possible to detonate the Radio Controlled Improvised Explosive Devices (RCIEDs). The preliminary laboratory tests of the...
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DETERMINATION OF SEAKEEPING PERFORMANCE FOR A CASE STUDY VESSEL BY THE STRIP THEORY METHOD
PublikacjaThe increase of seakeeping performance is of particular importance for car and passenger ferries, service ships in the gas and oil extraction industry and offshore wind power farm industry, as well as for special purpose ships (including military applications). In the water areas of the Baltic Sea, North Sea, and Mediterranean Sea, which are characterised by a short and steep wave, the hull shape has a substantial impact on the...
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Roads unsafety - social costs
PublikacjaThe condition of road safety has a significant impact on the quality of citizens' life. Yearly, one in a hundred families in Poland suffers because of road accidents. It is affected by them not only in material terms but first and foremost in moral terms. Road accidents are one of the main causes of degradation in the quality of life. In Poland we hardly know anything about the fate of the road traffic victims, their life problems...
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Device for spoofing in global positioning system
PublikacjaThis article describes the device which may be used to generate false GPS signals and emit them into radio communication channel. Such attack is called GPS spoofing. Each GPS receiver which remains in the range of a spoofing device (called spoofer) indicates time and position coordinates which are predetermined by the spoofer’s operator. Spoofing may be used e.g. in order to disable the terrorist group from obtaining correct navigation...
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Amino Acid Based Antimicrobial Agents – Synthesis and Properties
PublikacjaStructures of several dozen of known antibacterial, antifungal or antiprotozoal agents are based on the amino acid scaffold. In most of them, the amino acid skeleton is of a crucial importance for their antimicrobial activity, since very often they are structural analogs of amino acid intermediates of different microbial biosynthetic pathways. Particularly, some aminophosphonate or aminoboronate analogs of protein amino acids are...
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CSR – A FASHION OR REAL COMMITMENT? THE CASE OF POLISH LISTED COMPANIES
PublikacjaThis article, without claiming to be the ultimate reference, aims at assessing the social commitment of the large and solid financially, listed on the Warsaw Stock Exchange (WSE), Polish companies, on the eve of the implementation of the EU directive on disclosure of non-financial and diversity information (2014/95/EU). The selected companies seem perfect to form a vanguard of CSR in Poland, but the results of the analysis indicate...
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Accurate and continuous adhesive fracture energy determination using an instrumented wedge test
PublikacjaThe wedge test and the related double cantilever beam test are practical methods of assessing structural adhesive fracture energy. In the former, and to a lesser extent the latter, a recognised problem is the difficulty of following the length of the growing crack, required to calculate fracture energy with any accuracy. We present a novel method of measurement of crack length that has the advantages of being accurate and allowing...
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Bridging the gap between architectural and environmental engineering education in the context of climate change
PublikacjaIndicated in this article is the urgent need to adjust architectural education to the challenges triggered by climate change. Although reports on the future scenarios for cities are alarming, documents that set criteria for architectural education do not indicate competencies related to climate change adaptation and mitigation, mainly by avoiding environmental engineering considerations. An immediate answer to this problem could...
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Możliwości zamiany elektrycznych przepływomierzy powietrza stosowanych w silnikach spalinowych samochodów
PublikacjaW artykule przedstawiono podstawowe typy przepływomierzy powietrza, stosowane w silnikach spalinowych samochodów: z klapąspiętrzającą, HLM, HFM, Vortex i MAP. Przedstawiono wyniki badania tych przepływomierzy na specjalnie przygotowanym stanowisku pomiarowym. Przeanalizowano możliwość ich zamiany i zweryfikowano taką możliwość w praktyce.
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Review of ship safety domains: Models and applications
PublikacjaShip safety domain is a term which is widely used in research on collision avoidance and traffic engineering among others. Classic ship domains have been compared in multiple reports. However, up till now there has been no work summing up contemporary research in this field. The paper offers a systematic and critical review of the newer ship domain models and related research. It discusses multiple differences in approach to ship...
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The Perception of an Entrepreneur’s Structural, Relational and Cognitive Social Capital among Young People in Poland - An Exploratory Study
PublikacjaThe goal of the current paper is to verify how an entrepreneur’s structural, relational and cognitive social capital levels are perceived by young people in Poland. The research involved a group of 374 undergraduate business students from a Polish university as participants. Participants completed a survey on entrepreneurial cognitions. It was found that participants assess the level of an entrepreneur’s social capital as relatively...
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In uence of Low-Level Features Extracted from Rhythmic and Harmonic Sections on Music Genre Classi cation
PublikacjaWe present a comprehensive evaluation of the infuence of 'harmonic' and rhythmic sections contained in an audio file on automatic music genre classi cation. The study is performed using the ISMIS database composed of music files, which are represented by vectors of acoustic parameters describing low-level music features. Non-negative Matrix Factorization serves for blind separation of instrument components. Rhythmic components...
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Quantifying wage effects of offshoring: import- versus export-based measures of production fragmentation
PublikacjaIn this paper we examine the implications of international fragmentation of production on wages in the light of recent methodological developments in offshoring measurement. In particular, we compare the results stemming from two ways of quantifying offshoring – the traditional one based on import statistics and the one obtained from the decomposition of gross exports and input-output information. In the empirical part of our study,...
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Single-phase, Five-level Inverter with SPWM-Based Neutral Point Voltage Balancing Scheme
PublikacjaMultilevel inverter topologies provide several advantages over two-level inverter configuration. These benefits are the reason for the growing interest in multilevel topologies among research society. One of the most popular topological concepts (diode and active switch clamping) requires neutral-point potential balancing due to series-connected capacitor banks across the input dc link in such derived inverter configurations. This...
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Demonstrator technologii C-IED
PublikacjaArtykuł przedstawia budowę i działanie opracowanego na Politechnice Gdańskiej demonstratora technologicznego systemu AEGIS, przeznaczonego do przeciwdziałania atakom z wykorzystaniem prowizorycznych urządzeń wybuchowych detonowanych drogą radiową (RCIED — Radio Controlled Improvised Explosive Devices). Przedstawiono zaimplementowaną oryginalną metodę generowania sygnału zagłuszającego o dowolnie ukształtowanym widmie częstotliwościowym,...
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Project-Based Collaborative Research and Training Roadmap for Manufacturing Based on Industry 4.0
PublikacjaThe importance of the economy being up to date with the latest developments, such as Industry 4.0, is more evident than ever before. Successful implementation of Industry 4.0 principles requires close cooperation of industry and state authorities with universities. A paradigm of such cooperation is described in this paper stemming from university partners with partly overlapping and partly complementary areas of expertise in manufacturing....
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A Regional ITRF Densification by Blending Permanent and Campaign Data — The CEGRN campaigns and the Central European Velocity Field
PublikacjaThe CERGOP Project of the Central European Countries initiated six GPS observation campaigns from 1994 to 2001. By the high standards set within this project for site selection, observation and analysis a consistent set of epoch solutions with a precision in the 3–5 mm range was created. The network contains about 19 permanent and 38 epoch stations. In this paper a first combination solution over the seven years with a velocity...
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A comprehensive assessment of environmental pollution by means of heavy metal analysis for oysters' reefs at Hab River Delta, Balochistan, Pakistan
PublikacjaThe heavy metal pollution status of oyster reefs has been assessed with respect to ten metals pollutants in seawater, sediments, and tissues of above two oysters (soft tissues and shells) for assessing the pollution status in a short food chain in Hab River Delta. The results showed that heavy metals accumulated in M. bilineata were higher than those in M. cuttackensis. Simultaneously, the population of M. bilineata species has...
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Market Size, Competitiveness and Technological Frontier - the Impact of Trade Integration with the UE on Productivity in Polish Manufacturing Sectors
PublikacjaThis paper addresses the relationship between growth of relative productivity in Polish manufacturing sectors and forces stemming from trade integration with the EU. We look at the productivity growth from the perspective of relations between Polish manufacturing sectors and the foreign ones, focusing on partner countries from the enlarged EU. Empirical analysis is based on sector level bilateral data concerning both domestic (Polish)...
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Parallel Implementation of the Discrete Green's Function Formulation of the FDTD Method on a Multicore Central Processing Unit
PublikacjaParallel implementation of the discrete Green's function formulation of the finite-difference time-domain (DGF-FDTD) method was developed on a multicore central processing unit. DGF-FDTD avoids computations of the electromagnetic field in free-space cells and does not require domain termination by absorbing boundary conditions. Computed DGF-FDTD solutions are compatible with the FDTD grid enabling the perfect hybridization of FDTD...
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Discouraging Traffic Remapping Attacks in Local Ad Hoc Networks
PublikacjaQuality of Service (QoS) is usually provided in ad hoc networks using a class-based approach which, without dedicated security measures in place, paves the way to various abuses by selfish stations. Such actions include traffic remapping attacks (TRAs), which consist in claiming a higher traffic priority, i.e., false designation of the intrinsic traffic class so that it can be mapped onto a higher-priority class. In practice, TRAs...
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Processes of enhancing the intelligence of Learning Organizations on the basis of Competence Centers
PublikacjaThe process of organizational learning and proper knowledge management became today one of the major challenges for the organization acting in the knowledge-based economy. According to the observations of the authors of this paper the demand for formalization of knowledge management processes and organizational learning is particularly evident in research institutions, established either by the universities, or the companies. The...
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Motility activity, slime production, biofilm formation and genetic typing by ERIC-PCR for Pseudomonas aeruginosa strains isolated from bovine and other sources (human and environment)
PublikacjaThe molecular-typing strategy, ERIC-PCR was used in an attempt to determine the genomic relationship of 28 P. aeruginosa strains isolated from faeces of healthy bovine, bovine mastitis and from faeces of hospital patients as well as from environment. ERIC-PCR fingerprinting revealed large molecular differentiation within this group of isolates. Twenty two out of 28 strains tested generated unique patterns of DNA bands and only...
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Modelling of heat transfer in supercritical pressure recuperators
PublikacjaIn the paper presented is analysis of convective flow heat transfer at supercritical pressure in channels of heat exchanger working in the thermodynamic cycle. The modelling is based on the division of the flow into three regions, namely the heavy fluid, a two phase flow consisting of the heavy and light fluids and finally the light fluid flow. Modelling is concentrated on the region of simultaneous flow of two fluids divided into...
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Recent advances in 3D bioprinted tumor models for personalized medicine
PublikacjaCancerous tumors are among the most fatal diseases worldwide, claiming nearly 10 million lives in 2020. Due to their complex and dynamic nature, modeling tumors accurately is a challenging task. Current models suffer from inadequate translation between in vitro and in vivo results, primarily due to the isotropic nature of tumors and their microenvironment's relationship. To address these limitations, hydrogel-based 3D bioprinting...
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Windowing of the Discrete Green's Function for Accurate FDTD Computations
PublikacjaThe paper presents systematic evaluation of the applicability of parametric and nonparametric window functions for truncation of the discrete Green's function (DGF). This function is directly derived from the FDTD update equations, thus the FDTD method and its integral discrete formulation can be perfectly coupled using DGF. Unfortunately, the DGF computations require processor time, hence DGF has to be truncated with appropriate...
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Hydrodynamic Model of the New Waterway through the Vistula Spit
PublikacjaThe decision to build a new waterway (strait) in the Polish part of the Vistula Spit was made in 2017. The new connection between the Gulf of Gdańsk and the Vistula Lagoon is planned as an artificial navigable channel with a lock and a small port. During storm surges and wind tides in the gulf or in the lagoon, sluicing will be re-quired for vessels to tackle the Vistula Spit. This procedure does not require significant water flow...
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A comprehensive survey on low-cost ECG acquisition systems: Advances on design specifications, challenges and future direction
PublikacjaAvailability of low-cost, reliable, and portable Electrocardiography (ECG) devices is still very important in the medical world today. Despite the tremendous technological advancement, Cardiovascular Diseases (CVDs) remain a serious health burden claiming millions of lives on an annual basis globally. This is more prevalent in Low and Middle-Income Countries (LMICs) where there are huge financial instability and lack of critical...
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A five-year retrospective study shows increasing rates of antimicrobial drug resistance in Cabo Verde for both Staphylococcus aureus and Escherichia coli
PublikacjaObjectives Data on baseline drug resistance is important in informing future antimicrobial stewardship programs. So far, no data on the antimicrobial drug resistance of clinical isolates was available for the African archipelago of Cabo Verde. Methods We have performed a retrospective analysis over five-years (2013-17) of the antimicrombial drug susceptibility profiles of clinical isolates in the two main hospitals of Cabo Verde....
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System wykrywania i przeciwdziałania spoofingowi GPS
PublikacjaSpoofing w systemach nawigacji satelitarnej jest atakiem elektronicznym, który polega na nieuprawnionej emisji sygnałów stanowiących imitacje rzeczywistych sygnałów odbieranych z satelitów. Powoduje on wyznaczenie nieprawidłowych informacji o czasie, położeniu i prędkości odbiornika. Z uwagi na trudność jego wykrycia, spoofing stanowi poważniejsze zagrożenie niż proste zagłuszanie sygnałów zakłóceniem o dużej mocy (ang. jamming)....
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Parametric Study on a Performance of a Small Counter-Rotating Wind Turbine
PublikacjaA small Counter-Rotating Wind Turbine (CRWT) has been proposed and its performancehas been investigated numerically. Results of a parametric study have been presented in this paper.As parameters, the axial distance between rotors and a tip speed ratio of each rotor have been selected.Performance parameters have been compared with reference to a Single Rotor Wind Turbine (SRWT).Simulations were carried out with Computational Fluids...