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Position and Orientation Estimation in Radio Network With Groups of Locally Synchronized Nodes
PublicationThis article presents a positioning system with groups of locally synchronized nodes. A mobile object is equipped with a group of several synchronized receivers that are able to measure the difference in the time of arrival of signals from reference transmitters. The reference transmitters are synchronized only in local groups, with no global synchronization between groups. It is assumed that the synchronous operation of transmitters...
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Threshold Attendance under Soft-Crash Model: TAG Protocol and Markovian Analysis
PublicationA realistic and systematic network evaluation should subsume an availability model and a failure model. We combine a "hard availability" model we call threshold attendance, whereby a certain minimum number of network elements must be present at any time, with a soft-crash failure model, whereby after experiencing a failure, a network element is still able to function correctly for a while in an emergency mode at a risk of a major...
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Fast-response optoelectronic detection of explosives’ residues from the nitroaromatic compounds detonation: field studies approach
PublicationWe are presenting an application of optoelectronic nitrogen dioxide (NO2) analyzer based on cavity enhanced absorption spectroscopy in the detection of traces of explosives after detonation. It has been shown that the analyzer using blue-violet laser is able to detect explosive residues after the detonation of various amounts of nitroaromatic compounds (75g-1kg) with higher efficiency than the HPLC soil sample testing equipment,...
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Properties and Formation of Mineralized Veins in an Organic-Rich Shale Formation
PublicationAn earlier paper defined mineral and organic matter constituents in weak interfaces in shale formations (Ptaszynska, et. al., 2016). The formation studied in the earlier work and here is the Jurassic, early-Cretaceous Vaca Muerta formation in the Neuquen basin in Argentina. In this earlier work, mineralized "veins" were noted to be prevalent and complicated, sometimes being shear weak interfaces while in other cases they were not....
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Adaptive traffic optimization using Variable Speed Limits; Adaptacyjna optymalizacja ruchu drogowego przy pomocy zmiennych ograniczeń prędkości
PublicationVariable speed limits (VSL) is an intelligent transportation system (ITS) solution for traffic management. The speed limits can be changed dynamically in order to adapt to traffic, weather, or road surface conditions. This paper presents an approach for such an adaptive traffic control where the primary goal is to ensure traffic safety and efficiency of the traffic control system (fast response to dynamically changing traffic,...
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Stress Monitoring System for Individuals with Autism Spectrum Disorders
PublicationIn this article, a stress monitoring system tailored for individuals with Autism Spectrum Disorders (ASD) and developed for the educational institution is presented. People with ASD face problems with effective stress management due to their high self-perceived levels of stress, poor ability to cope with it, and dificulties with the accurate detection of the source of stress. Consistently, being able to measure stress appears to...
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Analysis of an Attenuator Artifact in an Experimental Attack by Gunn–Allison–Abbott Against the Kirchhoff-Law–Johnson-Noise (KLJN) Secure Key Exchange System
PublicationA recent paper by Gunn–Allison–Abbott (GAA) [L. J. Gunn et al., Scientific Reports 4 (2014) 6461] argued that the Kirchhoff-law–Johnson-noise (KLJN) secure key exchange system could experience a severe information leak. Here we refute their results and demonstrate that GAA’s arguments ensue from a serious design flaw in their system. Specifically, an attenuator broke the single Kirchhoff-loop into two coupled loops, which is an...
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TIME-AND-SPACE STRUCTURE OF FORCE-DRIVEN RIGID SPHEREWAVEFIELD
PublicationThis paper introduces a time-domain, causality-inspired description of a vector-source acoustic wavefield of arbitrary time evolution, where a sphere is a practical realisation of quasi-point contact surface without which a point force would not be able to exert an impact onto non-viscous fluid. At every space location, the resulting acoustic field is described by a pair of physical variables characterising the time evolution of...
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Investigation on Damage-Involved Structural Response of Colliding Steel Structures during Ground Motions
PublicationEarthquakes are the most unpredictable damaging loads which can affect civil engineering structures. Due to insufficient separation distance between adjacent structures with different dynamic properties, structural collisions may occur during ground motions. Although the research on structural pounding has recently been much advanced, the studies have mainly been conducted for concrete structures. The aim of this paper is to show...
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Reliable routing and resource allocation scheme for hybrid RF/FSO networks
PublicationSignificant success of wireless networks in the last decade has changed the paradigms of communication networks design. In particular, the growing interest in wireless mesh networks (WMNs) is observed. WMNs offer an attractive alternative to conventional cable infrastructures, especially in urban areas, where the cost of new installations is almost prohibitive. Unfortunately, the performance of WMNs is often limited by the cluttered...
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Cross-layer mDNS/ARP integration for IEEE 802.11s Wireless mesh Network
PublicationPopularization of mobile computing devices created a need for robust, efficient and ubiquitous methods of communication and network access. At the same time, evolution and standardization of Wireless Local Area Network (WLAN) technologies made them an attractive solution for building of complex network systems. Moreover, growing maturity of WLAN standards such as IEEE 802.11 allows for introduction of WLAN architectures other than...
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Modeling of the Two-Dimensional Flow Caused by Sea Conditions and Wind Stresses on the Example of Dead Vistula
PublicationThe article presents the results of two-dimensional modeling of flows caused by the sea conditions and wind stresses on the example of Dead Vistula. Based on the available bathymetric data, a numerical model of the river section was created, which was supplemented with data on the position of the water table depending on hydrometeorological conditions. To describe the flow field in steady conditions, a simplified model of two-dimensional...
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Numerical evaluation of dynamic response of an experimentally tested base-isolated and fixed-base steel structure model
PublicationSeismic isolation is recognized as one of the most popular and effective methods of protecting structures during earthquake. The present paper is focused on the comparison be-tween the dynamic responses of buildings with fixed and isolated bases exposed to seismic exci-tations. The aim of the study is to investigate the effectiveness of a simplified base isolation numerical modelling technique using the linear springs. One-storey...
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The In-Depth Studies of Pulsed UV Laser-Modified TiO2 Nanotubes: The Influence of Geometry, Crystallinity, and Processing Parameters
PublicationThe laser processing of the titania nanotubes has been investigated in terms of morphology, structure, and optical properties of the obtained material. The length of the nanotubes and crystallinity, as well as the atmosphere of the laser treatment, were taken into account. The degree of changes of the initial geometry of nanotubes were checked by means of scanning electron microscopy, which visualizes both the surface and the cross-section....
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COMPARISON OF SYSTEM ON CHIP TECHNOLOGIES FOR SPACE APPLICATIONS
PublicationThe paper presents a review of technologies available for the implementation of digital and mixed signal systems, particularly the system on a chip (SoC) for space applications. The phenomena encountered in the space environment are briefly presented, together with the known solutions, regarding the design of complex electronic systems. The most important norms regarding single die integrated circuits designed for space are also...
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BE OPEN European forum and oBsErvatory for OPEN science in transport
ProjectsProject realized in Main Library Office according to 824323 — BE OPEN — H2020-MG-2018-2019-2020/H2020-MG-2018-SingleStage-INEA agreement from 2018-12-03
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Heart rate PPG signals with acceleration captured at wrist during small and moderate body movements
Open Research DataHeart rate PPG signals with acceleration captured at wrist during small and moderate body movements
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From Scores to Predictions in Multi-Label Classification: Neural Thresholding Strategies
PublicationIn this paper, we propose a novel approach for obtaining predictions from per-class scores to improve the accuracy of multi-label classification systems. In a multi-label classification task, the expected output is a set of predicted labels per each testing sample. Typically, these predictions are calculated by implicit or explicit thresholding of per-class real-valued scores: classes with scores exceeding a given threshold value...
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Diagnostyka łożysk silnika indukcyjnego na podstawie prądu zasilającego przy użyciu sztucznych sieci neuronowych
PublicationW artykule zawarto wyniki badań dotyczące diagnostyki łożysk silnika indukcyjnego na podstawie pomiarów prądu zasilającego z wykorzystaniem sztucznych sieci neuronowych. Zaprezentowano wyniki uczenia sieci oraz rezultaty testów przeprowadzonych na danych spoza zbioru uczącego. Badania wykonane zostały na obiektach z celowo wprowadzonymi uszkodzeniami łożysk. Przedstawiona nowa koncepcja zakłada użycie zestawu sieci neuronowych...
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Hydraulika i Hydrologia II - 2021/22
e-Learning CoursesHydraulika i Hydrologia II to kurs poświęcony zagadnieniom przepływu wody w ośrodku gruntowym, kanałach i rzekach, którego celem jest nabycie i poszerzenie wiedzy i umiejętności związanych z opisem występujących zjawisk hydraulicznych i hydrologicznych. WYKŁADWoda w gruncie i hydraulika wód gruntowych, infiltracja. Odpływ ze zlewni. Opad efektywny i spływ powierzchniowy, chwilowy hydrogram jednostkowy. Przepływ w ciekach, przepływ...
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Zagadnienia tribologiczne w hamulcu silnika hydraulicznego
PublicationPrzedmiotem badań był prototypowy hamulec cierny wielopłytkowy do silnika satelitowego SM-0,6 o teoretycznej objętości roboczej 16,7 cm3/obr. Hamulec ten zbudowany był z 27 tarcz ciernych wykonanych z materiału TOLOX oraz z pakietu sprężyn talerzowych zamontowanych w układzie X. Zablokowanie hamulca następuje w skutek siły docisku pakietu sprężyn talerzowych płytek ciernych co następuje w chwili spadku ciśnienia w komorze tłoka...
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Halucynacje chatbotów a prawda: główne nurty debaty i ich interpretacje
PublicationGeneratywne systemy sztucznej inteligencji (SI) są w stanie tworzyć treści medialne poprzez zastosowanie uczenia maszynowego do dużych ilości danych szkoleniowych. Te nowe dane mogą obejmować tekst (np. Bard firmy Google, LLaMa firmy Meta lub ChatGPT firmy OpenAI) oraz elementy wizualne (np. Stable Diffusion lub DALL-E OpenAI) i dźwięk (np. VALL-E firmy Micro- soft). Stopień zaawansowania tych treści może czynić je nieodróżnialnymi...
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Dynamics of productivity in higher education. Cross-European evidence based on bootstrapped Malmquist indices
PublicationThis study presents patterns of productivity change in a large set of 266 public higher education institutions (HEIs) from 7 European countries across the time period 2001-2005. We adopt consistent bootstrap estimation procedures to obtain confidence intervals for Malmquist indices of HEI productivity and their components. Consequently, we are able to assess statistical significance of the changes in HEIs' productivity, efficiency...
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Efficiency of linear and non-linear classifiers for gas identification from electrocatalytic gas sensor
PublicationElectrocatalytic gas sensors belong to the family of electrochemical solid state sensors. Their responses are acquired in the form of I-V plots as a result of application of cyclic voltammetry technique. In order to obtain information about the type of measured gas the multivariate data analysis and pattern classification techniques can be employed. However, there is a lack of information in literature about application of such...
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Information Retrieval in Wikipedia with Conceptual Directions
PublicationThe paper describes our algorithm used for retrieval of textual information from Wikipedia. The experiments show that the algorithm allows to improve typical evaluation measures of retrieval quality. The improvement of the retrieval results was achieved by two phase usage approach. In first the algorithm extends the set of content that has been indexed by the specified keywords and thus increases the Recall value. Then, using the...
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AN EXPERIMENTAL AND NUMERICAL STUDY ON THE PERFORMANCE OF AN INNOVATIVE VERTICAL-AXIS WIND TURBINE
PublicationThis paper introduces the innovative modification of the Savonius wind turbine being able to significantly increase efficiency in comparison with the classic design. This innovative design is equipped with a stator directing the flow. The presence of the stator increases the active surface area and generates higher torques acting on a shaft. Additionally, it makes it possible to take better advantage of wind energy and compensate...
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An IoT-Based Computational Framework for Healthcare Monitoring in Mobile Environments
PublicationThe new Internet of Things paradigm allows for small devices with sensing, processing and communication capabilities to be designed, which enable the development of sensors, embedded devices and other ‘things’ ready to understand the environment. In this paper, a distributed framework based on the internet of things paradigm is proposed for monitoring human biomedical signals in activities involving physical exertion. The main...
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Failure mode prediction for composite structural insulated panels with MgO board facings
PublicationSandwich panels are readily used in civil engineering due to their high strength to weight ratio and the ease and speed of assembly. The idea of a sandwich section is to combine thin and durable facings with a light-weight core and the choice of materials used allows obtaining the desired behaviour. Panels in consideration consist of MgO (magnesium oxide) board facings and expanded polystyrene core and are characterized by immunity...
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Dynamic GNSS Mission Planning Using DTM for Precise Navigation of Autonomous Vehicles
PublicationNowadays, the most widely used method for estimating location of autonomous vehicles in real time is the use of Global Navigation Satellite Systems (GNSS). However, positioning in urban environments using GNSS is hampered by poor satellite geometry due to signal obstruction created by both man-made and natural features of the urban environment. The presence of obstacles is the reason for the decreased number of observed satellites...
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Feasibility Study for Food Intake Tasks Recognition Based on Smart Glasses
PublicationIn this exploratory study 13 adult test subjects have performed different food intake tasks while wearing a three axis accelerometer mounted at a temple of glasses. Two different algorithms for task recognition have been applied and compared. The retrospective data processing leads to better task recognition results when the frequency range of 50 Hz to 100 Hz is analysed within accelerometer signal recordings. A straightforward...
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Recuperator with microjet technology as a proposal for heat recovery from low-temperature sources
PublicationA tendency to increase the importance of so called dispersed generation, based on the local energy sources and the working systems uti- lizing both the fossil fuels and the renewable energy resources is observed nowadays. Generation of electricity on industrial or domestic scale together with production of heat can be obtained for example through employment of the ORC systems. It is mentioned in the EU directive 2012/27/EU for...
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Versatility of putative aromatic aminotransferases from Candida albicans.
PublicationAmino acids constitute the key sources of nitrogen for growth of Candida albicans. In order to survive inside the host in different and rapidly changing environments, this fungus must be able to adapt via its expression of genes for amino acid metabolism. We analysed the ARO8, ARO9, YER152C, and BNA3 genes with regards to their role in the nutritional flexibility of C. albicans. CaAro8p is undoubtedly the most versatile enzyme...
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A family of new generation miniaturized impedance analyzers for technical object diagnostics
PublicationThe paper presents the family of three analyzers allowing to measure impedance in range of 10 ohm<|Zx|<10 Gohm in a wide frequency range from 10 mHz up to 100 kHz. The most important features of the analyzers family are: miniaturization, low power consumption, low production cost, telemetric controlling and the use of impedance measurement method based on digital signal processing DSP. The miniaturization and other above mentioned...
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From Knowledge based Vision Systems to Cognitive Vision Systems: A Review
PublicationComputer vision research and applications have their origins in 1960s. Limitations in computational resources inherent of that time, among other reasons, caused research to move away from artificial intelligence and generic recognition goals to accomplish simple tasks for constrained scenarios. In the past decades, the development in machine learning techniques has contributed to noteworthy progress in vision systems. However,...
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Clean energy in the European Union: Transition or evolution?
PublicationIn this paper, we analyse two phenomena. First, the relationship between greenhouse gases emission and effectiveness of the European Union energy policies and second the transition from the fossil fuels to renewable energy sources. We run two-step data analysis concerning 25 European Union member states in the period from 1990 to 2018. We use information on greenhouse gases emission, introduction of new energy policies, source...
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DMSO and TMAO—Differences in Interactions in Aqueous Solutions of the K-Peptide
PublicationInteractions between a solvent and their co-solute molecules in solutions of peptides are crucial for their stability and structure. The K-peptide is a synthetic fragment of a larger hen egg white lysozyme protein that is believed to be able to aggregate into amyloid structures. In this study, a complex experimental and theoretical approach is applied to study systems comprising the peptide, water, and two co-solutes: trimethylamide...
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A Survey of Vehicular Network Systems for Road Traffic Management
PublicationIn this survey, we analyze the proposals of vehicular communication systems in the context of road traffic management. Starting with the definition of communications between vehicles (V2V), vehicles-to-infrastructure (V2I) and vehicles-to-everything (V2X), we first focus on the requirements and current standards for the Intelligent Transport Systems (ITS), including the maximum communication delay, the communication range and the...
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Comparable analysis of PID controller settings in order to ensure reliable operation of active foil bearings
PublicationIn comparison to the traditional solutions, active bearings offer great operating flexibility, ensure better operating conditions over a wider range of rotational speeds and are safe to use. In order to ensure optimum bearing performance a bearing control system is used that adapts different geometries during device operation. The selection of optimal controller parameters requires the use of modern optimization methods that make...
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Fatigue fracture surface metrology of thin-walled tubular austenitic steel specimens after asynchronous loadings
PublicationThis paper aims to study the effect of asynchronous axial-torsional strain-controlled loading histories on fracture surface behavior of thin-walled tubular X5CrNi18-10 (304/304L) austenitic steel specimens. Tests under pure axial loading and pure torsional loading are also conducted to better segregate the effect of multiaxiality. The fractures surface topographies were examined through the profiles over the entire surface with...
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Evaluation of Langmuir and Freundlich Isotherms for Removal of Cephalexin and Tetracycline Antibiotics By Sistan Sand from Water and Wastewater Samples
PublicationIn this research, Sistan sand was used as a natural and inexpensive sorbent for removal of cephalexin and tetracycline antibiotics from water and wastewater samples. For a concentration 60.0 mg L-1 of cephalexin, optimum removal conditions were: pH of the sample 3.0, adsorbent amount 1.0 g, contact time 20.0 min, added amount of sodium chloride to adjust the ionic strength of the solution 7.0 g L-1. Langmuir isotherm was the best...
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Carbon nitride exfoliation for photocatalysis and photocatalytic ozonation over emerging contaminants abatement
PublicationThe production of graphitic carbon nitride was studied with the addition of a following exfoliation step using ultrasounds, at different times. The treatment produced catalysts with much higher surface areas, from 2.18 m2 g 1 with no treatment to 28.34 m2 g 1 after 36 h of exfoliation. During exfoliation, melem was also produced, and may further enhance the photoluminescence and photocatalytic properties. The photocatalytic reaction...
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Unsupervised Learning for Biomechanical Data Using Self-organising Maps, an Approach for Temporomandibular Joint Analysis
PublicationWe proposed to apply a specific machine learning technique called Self-Organising Maps (SOM) to identify similarities in the performance of muscles around human temporomandibular joint (TMJ). The performance was assessed by measuring muscle activation with the use of surface electromyography (sEMG). SOM algorithm used in the study was able to find clusters of data in sEMG test results. The SOM analysis was based on processed sEMG...
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Scheduling for Industrial Control Traffic Using Massive MIMO and Large Intelligent Surfaces
PublicationIndustry 4.0, with its focus on flexibility and customizability, is pushing in the direction of wireless communication in future smart factories, in particular massive multiple-input multiple-output (MIMO), and its future evolution Large Intelligent Surfaces (LIS), which provide more reliable channel quality than previous technologies. As such, there arises the need to perform efficient scheduling of industrial control traffic...
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Ideas of the New European Bauhaus (NEB) in architectural education
PublicationThe New European Bauhaus (NEB) is an interdisciplinary project initiated by the European Commission in 2020 [1], based on three values: sustainability, beauty and community (social inclusion). Its aim is to support the European Green Deal programme [2] by accelerating the transformation of various economic sectors, including construction, to improve the quality of people’s lives and protect the natural environment. Even though...
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Performance and Energy Aware Training of a Deep Neural Network in a Multi-GPU Environment with Power Capping
PublicationIn this paper we demonstrate that it is possible to obtain considerable improvement of performance and energy aware metrics for training of deep neural networks using a modern parallel multi-GPU system, by enforcing selected, non-default power caps on the GPUs. We measure the power and energy consumption of the whole node using a professional, certified hardware power meter. For a high performance workstation with 8 GPUs, we were...
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Transport of paracetamol in swellable and relaxing polyurethane nanocomposite hydrogels
PublicationPolyurethane hydrogels are potentially attractive materials for biomedical applications. They are able to absorb large amount of water, biological fluids or active substances, and thus, they have potential to be used as absorbents or wound-healing dressings. They are also used for the controlled release of therapeutics because of their capacity to embed biologically active agents in their water-swollen network. The presence of...
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Consequences of lysine auxotrophy for Candida albicans adherence and biofilm formation
PublicationA number of factors are known to be involved in Candida albicans virulence, although biofilm development on the surfaces of indwelling medical devices is considered to promote superficial or systemic disease. Based on previously reported up-regulation of saccharopine and acetyllysine in biofilm cells and activation of the lysine biosynthesis/degradation pathway, we investigated...
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Multimodal Particle Swarm Optimization with Phase Analysis to Solve Complex Equations of Electromagnetic Analysis
PublicationIn this paper, a new meta-heuristic method of finding roots and poles of a complex function of a complex variable is presented. The algorithm combines an efficient space exploration provided by the particle swarm optimization (PSO) and the classification of root and pole occurrences based on the phase analysis of the complex function. The method initially generates two uniformly distributed populations of particles on the complex...
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Miniature reconfigurable antenna
PublicationThis work concerns the design of a miniature, low-profile reconfigurable antenna based on Huygens metamaterial sources for frequency f0 = 2.45 GHz. Two planar Huygens sources were designed consisting of near-field resonators. Sources are excited from a specially designed reconfigurable control system. Thanks to the two PIN diodes, the system can realize two cardioid radiation characteristics with...
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STABILITY OF THE INNER SLOPE OF THE POLISH DREDGDIKES RESEARCH DIKE AT STATIONARY FLOW
PublicationFor long duration of the flood the water table can appear on the slope with a problem of out-wash in the case of sand type dike. If the dike corps is covered with less permeable layer some additional push-off forces and shearing can rise in the cover. In both cases the micro stability of the inner slope should be considered at normative high water for homogeneous sand type dike or sand type dike with less permeable covers. The...