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Rok 2021
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Studies on Aminoanthraquinone-Modified Glassy Carbon Electrode: Synthesis and Electrochemical Performance toward Oxygen Reduction
PublikacjaIn this paper, 9,10-anthraquinone (AQ) derivative-modified glassy carbon (GC) electrodes werestudied towards the electrochemical reduction of oxygen in aqueous and non-aqueous solutions. The reaction of 1-chloro-9,10-anthraquinone with aliphatic diamines was applied for the synthesis of amino-9,10-anthraquinone derivatives. The obtained AQ derivatives were grafted onto the surface of glassy carbon electrodes by electropolymerisation...
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Studies on Aminoanthraquinone-Modified Glassy Carbon Electrode: Synthesis and Electrochemical Performance toward Oxygen Reduction
PublikacjaIn this paper, 9,10-anthraquinone (AQ) derivative-modified glassy carbon (GC) electrodes were studied towards the electrochemical reduction of oxygen in aqueous and non-aqueous solutions. The reaction of 1-chloro-9,10-anthraquinone with aliphatic diamines was applied for the synthesis of amino-9,10-anthraquinone derivatives. The obtained AQ derivatives were grafted onto the surface of glassy carbon electrodes by electropolymerisation...
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Starter for Voltage Boost Converter to Harvest Thermoelectric Energy for Body-Worn Sensors
PublikacjaThis paper examines the suitability of selected configurations of ultra-low voltage (ULV) oscilla-tors as starters for a voltage boost converter to harvest energy from a thermoelectric generator (TEG). Important properties of particularly promising configurations, suitable for on-chip imple-mentation are compared. On this basis, an improved oscillator with a low startup voltage and a high output voltage swing is proposed. The applicability...
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Stanowisko badawcze do automatycznej analizy jakości transmisji koncentratora KODEŚ z interfejsami LTE, NB-IoT oraz ISM
PublikacjaZaprezentowano podstawowe właściwości projektowanego koncentratora danych elektroenergetycznych KODEŚ oraz stanowisko badawcze do automatycznych pomiarów jakości transmisji w sieci LTE (Long Term Evolution), opracowane na potrzeby projektu badawczego. Głównym elementem stanowiska jest autorskie oprogramowanie, które umożliwia konfigurowanie urządzeń pomiarowych oraz definiowanie scenariuszy pomiarowych. Dopełnieniem tego jest dodatkowe...
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Stable Field Electron Emission and Plasma Illumination from Boron and Nitrogen Co‐Doped Edge‐Rich Diamond‐Enhanced Carbon Nanowalls
PublikacjaSuperior field electron emission (FEE) characteristics are achieved in edge-rich diamond-enhanced carbon nanowalls (D-ECNWs) grown in a single-step chemical vapor deposition process co-doped with boron and nitrogen. The structure consists of sharp, highly conductive graphene edges supplied by a solid, diamond-rich bottom. The Raman and transmission electron microscopy studies reveal a hybrid nature of sp3-diamond and sp2-graphene...
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Software-Defined NB-IoT Uplink Framework - The Design, Implementation and Use Cases
PublikacjaIn the radiocommunication area, we may observe a rapid growth of new technology, such as 5G. Moreover, all the newly introduced radio interfaces, e.g., narrowband Internet of Things (NB-IoT), are strongly dependent on the software. Hence, the radiocommunication software development and optimization, as well as the 3GPP technical specification, should be introduced at the academic level of education. In this paper, a software-defined...
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Smart city and fire detection using thermal imaging
PublikacjaIn this paper, we summarize the results obtained from fire experiments. The aim of the work was to develop new methods of fire detection using IR thermal imaging cameras and dedicated image processing. We conducted 4 experiments in different configurations and with the use of different objects. The conducted experiments have shown the great usefulness of infrared cameras for detecting the seeds of a fire. Even cheap low-resolution...
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Skuteczność klasyfikacji gatunków muzycznych za pomocą sieci neuronowej w zależności od typu danych wejściowych
PublikacjaRozpoznawanie gatunku muzycznego jest jednym z podstawowych elementów inteligentnych systemów tworzenia automatycznych list muzyki. Platformy strumieniowe oferujące taką usługę wymagają rozwiązań, które umożliwią jak najdokładniej określić przynależność utworu do gatunku muzycznego. Zgodnie z aktualnym stanem wiedzy – najskuteczniejszym klasyfikatorem są sztuczne sieci neuronowe (w tym w wersji uczenia głębokiego), dla których...
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Simultaneous opto-electrochemical monitoring of carbamazepine and its electro-oxidation by-products in wastewater
PublikacjaThe growing human impact on aquatic environments, due to the extensive use of pharmaceuticals and the release of persistent pollutants, makes it necessary to implement new widespread methods for the characterisation and quantification of such contaminants and relative degradation products. Carbamazepine, 5H-dibenzo[b,f]azepine-5-carboxamide, (CBZ) is a widely used anti-epileptic drug, characterised by its limited removal by conventional...
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Simulator for Performance Evaluation of ASON/GMPLS Network
PublikacjaThe hierarchical control plane network architecture of Automatically Switched Optical Network with utilization of Generalized Multi-Protocol Label Switching protocols is compliant to next generation networks requirements and can supply connections with required quality of service, even with incomplete domain information. Considering connection control, connection management and network management, the controllers of this architecture...
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Simple 60 GHz Switched Beam Antenna for 5G Millimeter-Wave Applications
PublikacjaA new 60 GHz band single-input switched beam antenna is proposed for the fifth-generation (5G) millimeter-wave network applications. The presented design is capable of electronically switching the main beam in two different directions via a proposed microstrip-line-to-slotline single-pole dual-throw (SPDT) switch based on commercially available p-i-n diodes. The antenna is fabricated in a low-cost printed circuit board process...
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Signal Propagation in Electromagnetic Media Modelled by the Two-Sided Fractional Derivative
PublikacjaIn this paper, wave propagation is considered in a medium described by a fractional-order model, which is formulated with the use of the two-sided fractional derivative of Ortigueira and Machado. Although the relation of the derivative to causality is clearly specified in its definition, there is no obvious relation between causality of the derivative and causality of the transfer function induced by this derivative. Hence, causality...
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Sieci neuronowe oparte na prawach fizyki
PublikacjaWiele fizycznie nieuzasadnionych sieci neuronowych, mimo zadowalają- cej wydajności, generuje sprzeczności z logiką i prowadzi do rozbieżno- ści wyników z rzeczywistością. Jedną z metod poprawy funkcjonowania typowego modelu typu “black-box” na etapie uczenia, jest rozszerzenie jego funkcji kosztu o zależność bezpośrednio inspirowaną wzorem fizycz- nym. Niniejszy rozdział wyjaśnia koncepcję budowy sieci neuronowych opartych na...
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Service-based Resilience via Shared Protection in Mission-critical Embedded Networks
PublikacjaMission-critical networks, which for example can be found in autonomous cars and avionics, are complex systems with a multitude of interconnected embedded nodes and various service demands. Their resilience against failures and attacks is a crucial property and has to be already considered in their design phase. In this paper, we introduce a novel approach for optimal joint service allocation and routing, leveraging virtualized...
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Series-Slot-Fed Circularly Polarized Multiple-Input-Multiple-Output Antenna Array Enabling Circular Polarization Diversity for 5G 28-GHz Indoor Applications
PublikacjaIn this paper, a four-element circularly polarized series-slot-fed multiple-input-multiple-output (MIMO) antenna array with circular polarization diversity is presented. The proposed design utilizes a combination of 45-degree inclined slots and a straight microstrip line feeding technique. The two antennas are designed to operate with the opposite sense of circular polarization (CP). CP is achieved by placing a patch of just about...
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Semantic segmentation training using imperfect annotations and loss masking
PublikacjaOne of the most significant factors affecting supervised neural network training is the precision of the annotations. Also, in a case of expert group, the problem of inconsistent data annotations is an integral part of real-world supervised learning processes, well-known to researchers. One practical example is a weak ground truth delineation for medical image segmentation. In this paper, we have developed a new method of accurate...
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Self-assembly of vertically oriented graphene nanostructures: multivariate characterisation by Minkowski functionals and fractal geometry
PublikacjaThe enormous self-assembly potential that graphene and its derived layered materials offer for responding to the contemporary environmental challenges has made it one of the most investigated materials. Hence, tuning its extraordinary properties and understanding the effect at all scales is crucial to tailoring highly customised electrodes. Vertically oriented graphene nanostructures, also known as carbon nanowalls (CNWs), due...
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Selective monitoring of noise emitted by vehicles involved in road traffic
PublikacjaAn acoustic intensity probe was developed measures the sound intensity in three orthogonal directions, making possible to calculate the azimuth and elevation angles, describing the sound source position. The acoustic sensor is made in the form of a cube with a side of 10 mm, on the inner surfaces of which the digital MEMS microphones are mounted. The algorithm works in two stages. The first stage is based on the analysis of sound...
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Segmentation Quality Refinement in Large-Scale Medical Image Dataset with Crowd-Sourced Annotations
PublikacjaDeployment of different techniques of deep learning including Convolutional Neural Networks (CNN) in image classification systems has accomplished outstanding results. However, the advantages and potential impact of such a system can be completely negated if it does not reach a target accuracy. To achieve high classification accuracy with low variance in medical image classification system, there is needed the large size of the...
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Searching by heterogeneous agents
PublikacjaIn this work we introduce and study a pursuit-evasion game in which the search is performed by heterogeneous entities. We incorporate heterogeneity into the classical edge search problem by considering edge-labeled graphs: once a search strategy initially assigns labels to the searchers, each searcher can be only present on an edge of its own label. We prove that this problem is not monotone even for trees and we give instances...
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Scheduling with Complete Multipartite Incompatibility Graph on Parallel Machines
PublikacjaIn this paper we consider a problem of job scheduling on parallel machines with a presence of incompatibilities between jobs. The incompatibility relation can be modeled as a complete multipartite graph in which each edge denotes a pair of jobs that cannot be scheduled on the same machine. Our research stems from the works of Bodlaender, Jansen, and Woeginger (1994) and Bodlaender and Jansen (1993). In particular, we pursue the...
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Scheduling of compatible jobs on parallel machines
PublikacjaThe dissertation discusses the problems of scheduling compatible jobs on parallel machines. Some jobs are incompatible, which is modeled as a binary relation on the set of jobs; the relation is often modeled by an incompatibility graph. We consider two models of machines. The first model, more emphasized in the thesis, is a classical model of scheduling, where each machine does one job at time. The second one is a model of p-batching...
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Różnica w subiektywnej ocenie jakości mowy pomiędzy nastolatkami dwujęzycznymi a jednojęzycznymi
PublikacjaProces percepcji mowy omawiany jest w szerokim zakresie dziedzin i dyscyplin naukowych, od nauk humanistycznych, technicznych, aż po nauki medyczne. Wiele badań skupia się np. na ocenie różnicy w grupach bez i z wykształceniem muzycznym. Skoro stwierdzono, że zdolności muzyczne wpływają na percepcję poszczególnych atrybutów dźwięku, autorzy postanowili zbadać, czy zdolności językowe także mogą mieć wpływ na ocenę jakości sygnału...
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Room temperature depinning of the charge-density waves in quasi-two-dimensional 1T-TaS2 devices
PublikacjaWe report on the depinning of nearly commensurate charge-density waves in 1T-TaS2 thin films at room temperature. A combination of the differential current–voltage measurements with the low-frequency noise spectroscopy provides unambiguous means for detecting the depinning threshold field in quasi-2D materials. The depinning process in 1T-TaS2 is not accompanied by an observable abrupt increase in electric current—in striking contrast...
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Robustness in Compressed Neural Networks for Object Detection
PublikacjaModel compression techniques allow to significantly reduce the computational cost associated with data processing by deep neural networks with only a minor decrease in average accuracy. Simultaneously, reducing the model size may have a large effect on noisy cases or objects belonging to less frequent classes. It is a crucial problem from the perspective of the models' safety, especially for object detection in the autonomous driving...
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Robust Parameter Tuning of Antenna Structures by Means of Design Specification Adaptation
PublikacjaParameter tuning through numerical optimization has become instrumental in the design of high-performance antenna systems. Yet, practical optimization faces several major challenges, including high cost of massive evaluations of antenna characteristics, normally involving full-wave electromagnetic (EM) analysis, large numbers of adjustable variables, the shortage of reasonable initial solutions in the case of topologically complex...
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Robot-Based Intervention for Children With Autism Spectrum Disorder: A Systematic Literature Review
PublikacjaChildren with autism spectrum disorder (ASD) have deficits in the socio-communicative domain and frequently face severe difficulties in the recognition and expression of emotions. Existing literature suggested that children with ASD benefit from robot-based interventions. However, studies varied considerably in participant characteristics, applied robots, and trained skills. Here, we reviewed robot-based interventions targeting...
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Risk Analysis by a Probabilistic Model of the Measurement Process
PublikacjaThe aim of the article is presentation of the testing methodology and results of examination the probabilistic model of the measurement process. The case study concerns the determination of the risk of an incorrect decision in the assessment of the compliance of products by measurement. Measurand is characterized by the generalized Rayleigh distribution. The model of the meas-urement process was tested in parallel mode by six risk...
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Reversible Data Hiding in Encrypted DICOM Images Using Cyclic Binary Golay (23, 12) Code
PublikacjaIn this paper, a novel reversible data hiding method for encrypted images (RDHEI) is proposed. An efficient coding scheme based on cyclic binary Golay (23, 12) code is designed to embed additional data into the least significant bits (LSBs) of the encrypted image. The most significant bits (MSBs) are used to ensure the reversibility of the embedding process. The proposed scheme is lossless, and based on the receiver’s privileges,...
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Reprezentacja danych dźwiękowych w kontekście metod uczenia maszynowego
PublikacjaDźwięk odgrywa kluczową rolę w przekazywaniu informacji lub ostrzeganiu o niebezpieczeństwie. Do opracowania wydajnego cyfrowego asystenta głosowego zdolnego do efektywnej współpracy z człowiekiem niezbędne jest użycie algorytmów opisujących sygnał dźwiękowy w formie cyfrowej. W poniższej pracy skategoryzowano i opisano najpowszechniejsze metody opisu sygnałów audio używanych jako wejścia dla algorytmów uczenia maszynowego. Wskazano...
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Remote command and control capabilities for data acquisition systems provided by delay-tolerant network mechanisms
PublikacjaThe paper presents an assessment of a remote device reconfiguration service employing a Delay Tolerant Network (DTN) mechanisms. This service has been implemented as a part of a communication appliance dedicated to marine data transfer in off-shore and open sea areas. The service has been successfully deployed and validation test have been completed. The practical use-case has been defined as remote access to the equipment operating...
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Relay-aided Wireless Sensor Network Discovery Algorithm for Dense Industrial IoT utilizing ESPAR Antennas
PublikacjaIndustrial Internet of Things (IIoT) applicationsrequire reliable and efficient wireless communication. Assumingdense Wireless Sensor Networks (WSNs) operating in a harshenvironment, a concept of a Time Division Multiple Access(TDMA) based WSN enriched with Electronically SteerableParasitic Array Radiator (ESPAR) antennas is proposed andexamined in this work. The utilized...
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Reinforcement Learning Algorithm and FDTD-based Simulation Applied to Schroeder Diffuser Design Optimization
PublikacjaThe aim of this paper is to propose a novel approach to the algorithmic design of Schroeder acoustic diffusers employing a deep learning optimization algorithm and a fitness function based on a computer simulation of the propagation of acoustic waves. The deep learning method employed for the research is a deep policy gradient algorithm. It is used as a tool for carrying out a sequential optimization process the goal of which is...
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Regularized Local Basis Function Approach to Identification of Nonstationary Processes
PublikacjaThe problem of identification of nonstationary stochastic processes (systems or signals) is considered and a new class of identification algorithms, combining the basis functions approach with local estimation technique, is described. Unlike the classical basis function estimation schemes, the proposed regularized local basis function estimators are not used to obtain interval approximations of the parameter trajectory, but provide...
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Regularized Identification of Time-Varying FIR Systems Based on Generalized Cross-Validation
PublikacjaA new regularization method is proposed and applied to identification of time-varying finite impulse response systems. We show, that by a careful design of the regularization constraint, one can improve estimation results, especially in the presence of strong measurement noise. We also show that the the most appropriate regularization gain can be found by direct optimization of the generalized cross-validation criterion.
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Regularized identification of fast time-varying systems - comparison of two regularization strategies
PublikacjaThe problem of identification of a time-varying FIR system is considered and solved using the local basis function approach. It is shown that the estimation (tracking) results can be improved by means of regularization. Two variants of regularization are proposed and compared: the classical L2 (ridge) regularization and a new, reweighted L2 one. It is shown that the new approach can outperform the classical one and is computationally...
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Reduced-Cost Microwave Design Closure by Multi-Resolution EM Simulations and Knowledge-Based Model Management
PublikacjaParameter adjustment through numerical optimization has become a commonplace of contemporary microwave engineering. Although circuit theory methods are ubiquitous in the development of microwave components, the initial designs obtained with such tools have to be further tuned to improve the system performance. This is particularly pertinent to miniaturized structures, where the cross-coupling effects cannot be adequately accounted...
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Recent Developments in Data-Assisted Modeling of Flexible Proteins
PublikacjaMany proteins can fold into well-defined conformations. However, intrinsically-disordered proteins (IDPs) do not possess a defined structure. Moreover, folded multi-domain proteins often digress into alternative conformations. Collectively, the conformational dynamics enables these proteins to fulfill specific functions. Thus, most experimental observables are averaged over the conformations that constitute an ensemble. In this...
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Recent Advances in Accelerated Multi-Objective Design of High-Frequency Structures using Knowledge-Based Constrained Modeling Approach
PublikacjaDesign automation, including reliable optimization of engineering systems, is of paramount importance for both academia and industry. This includes the design of high-frequency structures (antennas, microwave circuits, integrated photonic components), where the appropriate adjustment of geometry and material parameters is crucial to meet stringent performance requirements dictated by practical applications. Realistic design has...
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Real-time isothermal DNA amplification monitoring in picoliter volumes using an optical fiber sensor
PublikacjaRolling circle amplification (RCA) of DNA can be considered as a great alternative to the gold standard polymerase chain reaction (PCR), especially during this pandemic period, where rapid, sensitive, and reliable test results for hundreds of thousands of samples are required daily. This work presents the first research to date on direct, real-time and label-free isothermal DNA amplification monitoring using a microcavity in-line...
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Rapid Multi-Criterial Antenna Optimization by Means of Pareto Front Triangulation and Interpolative Design Predictors
PublikacjaModern antenna systems are designed to meet stringent performance requirements pertinent to both their electrical and field properties. The objectives typically stay in conflict with each other. As the simultaneous improvement of all performance parameters is rarely possible, compromise solutions have to be sought. The most comprehensive information about available design trade-offs can be obtained through multi-objective optimization...
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QUASI-DISTRIBUTED NETWORK OF LOW-COHERENCE FIBER-OPTIC FABRY-PÉROT SENSORS WITH CAVITY LENGTH-BASED ADDRESSING
PublikacjaDistributed measurement often relies on sensor networks. In this paper, we present the construction of low coherent fiber-optic Fabry-Pérot sensors connected into a quasi-distributed network. We discuss the mechanism of spectrum modulation in this type of sensor and the constraints of assembly of such sensors in the network. Particular attention was paid to separate the signals from individual sensors, which can be achieved by...
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Quantum randomness protected against detection loophole attacks
PublikacjaDevice and semi-device-independent private quantum randomness generators are crucial for applications requiring private randomness. However, they are vulnerable to detection inefficiency attacks and this limits severely their usage for practical purposes. Here, we present a method for protecting semi-device-independent private quantum randomness generators in prepare-and-measure scenarios against detection inefficiency attacks....
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Quantitative fluorescent determination of DNA – Ochratoxin a interactions supported by nitrogen-vacancy rich nanodiamonds
PublikacjaOchratoxin A (OTA) is a hazardous contaminant of a large variety of plant and animal originated food. Herein, we report an interaction of OTA with calf thymus DNA (ct DNA) on the nanodiamond surface. We employed multispectroscopic techniques to elucidate the binding mechanism of OTA with ct DNA. The fluorescence and UV–Vis spectroscopy results show that OTA binds to ds ct DNA and forms complexes. We obtained the binding constants...
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Quality of Satellite Communication in Selected Mobile Android Smartphones
PublikacjaToday, thanks to mobile devices, satellite communication is available to anyone and everywhere. Gaining information on one’s position using GNSS (Global Navigation Satellite Systems), particularly in unknown urban environments, had become an everyday activity. With the widespread of mobile devices, particularly smartphones, each person can obtain information considering his or her location anytime and everywhere. This paper is...
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Pulsed UV-irradiated Graphene Sensors for Ethanol Detection at Room Temperature
PublikacjaA graphene-based gas sensor fabricated in a FET (GFET) configuration and its sensitivity towards ethanol and methane is reported. Detection of ethanol at the level of 100 ppm was observed under pulsed UV irradiation and after cleaning by UV light in the N2 ambient. Reduction of the frequency of UV irradiation pulses resulted in increased changes in sensor resistance in the presence of ethanol. Improved sensing behavior was ascribed...
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Progress on Roman and Weakly Connected Roman Graphs
PublikacjaA graph G for which γR(G)=2γ(G) is the Roman graph, and if γwcR(G)=2γwc(G), then G is the weakly connected Roman graph. In this paper, we show that the decision problem of whether a bipartite graph is Roman is a co-NP-hard problem. Next, we prove similar results for weakly connected Roman graphs. We also study Roman trees improving the result of M.A. Henning’s A characterization of Roman trees, Discuss. Math. Graph Theory 22 (2002)....
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Production of six-degrees-of-freedom (6DoF) navigable audio using 30 Ambisonic microphones
PublikacjaThis paper describes a method for planning, recording, and post-production of six-degrees-of-freedom audio recorded with multiple 3rd order Ambisonic microphone arrays. The description is based on the example of recordings conducted in August 2020 with the Poznan Philharmonic Orchestra using 30 units of Zylia ZM-1S. A convenient way to prepare and organize such a big project is proposed – this involves details of stage planning,...
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Process of Medical Dataset Construction for Machine Learning-Multifield Study and Guidelines
PublikacjaThe acquisition of high-quality data and annotations is essential for the training of efficient machine learning algorithms, while being an expensive and time-consuming process. Although the process of data processing and training and testing of machine learning models is well studied and considered in the literature, the actual procedures of obtaining data and their annotations in collaboration with physicians are in most cases...
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Problemy jakości w metodach Agile
PublikacjaZwinne metody wytwarzania osiągnęły w zawrotnym tempie niebywały sukces. Według różnych doniesień od 50 do 70% firm IT stosuje metody zwinne na stałe lub okazjonalnie . Jednak znaczna część firm stosuje wybiórczo praktyki zalecane przez Agile . Jakie to praktyki? Jakie problemy występują przy ich stosowaniu i jak firmy radzą sobie z tymi problemami? Jak wpływają na jakość wytwarzanego oprogramowania? Jakie są warunki krytyczne...