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Search results for: SUBARACHNOID SPACE WIDTH
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Is This Distance Teaching Planning That Bad?
PublicationIn spring 2020, university courses were moved into the virtual space due to the Covid-19 lockdown. In this paper, we use experience from courses at Gdańsk University of Technology and ETH Zurich to identify core problems in distance teaching planning and to discuss what to do and what not to do in teaching planning after the pandemic. We conclude that we will not return to the state of (teaching) affairs that we had previously....
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Comparative Study of Integer and Non-Integer Order Models of Synchronous Generator
PublicationThis article presents a comparison between integer and non-integer order modelling of a synchronous generator, in the frequency domain as well as in the time domain. The classical integer order model was compared to one containing half -order systems. The half-order systems are represented in a Park d-q axis equivalent circuit as impedances modelled by half-order transmittances. Using a direct method based on the approximation...
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Optimization of Wireless Networks for Resilience to Adverse Weather Conditions
PublicationIn this chapter, we consider how adverse weather conditions such as rain or fog affect the performance of wireless networks, and how to optimize these networks so as to make them robust to these conditions. We first show how to analyze the weather conditions in order to make them useful for network optimization modelling. Using an example realistic network, we show how to optimize two types of wireless networks: free-space optical...
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Virtual reality technology in architectural education
PublicationContemporary virtual reality (VR) technology allows the recreation of non-existent architectural objects of which there may be no trace remaining. Virtual reality applications allow access to digital models, which visualise the lost architecture. The popularity of VR has resulted in it being applied not only to computer games, but also in visualising the past. Maps allow movement through historical trails and 3D models of architecture...
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Design and Optimization of a Compact Super-Wideband MIMO Antenna with High Isolation and Gain for 5G Applications
PublicationThis paper presents a super-wideband multiple-input multiple-output (SWB MIMO) antenna with low profile, low mutual coupling, high gain and compact size for microwave and millimeter wave (mm-wave) fifth-generation (5G) applications. A single antenna is a simple elliptical-square shape with a small physical size of 20 × 20 × 0.787 mm3. The combination of both square and elliptical shapes results in an exceptionally broad impedance...
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The influence of the Cu2O deposition method on the structure, morphology and photoresponse of the ordered TiO2NTs/Cu2O heterojunction
PublicationThe increased interest in highly ordered titania structures exhibiting tubular shape that could be directly formed onto the stable substrate is related with the intensive research on their modification enabling absorption of light within the wide solar spectrum and its further conversion into electric or chemical energy. Among others, formation of uniform 3D heterojunctions based on the TiO2 nanotubes attracts attention since porous...
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Numerical analysis of high temperature minichannels heat exchanger performance
PublicationNowadays, the most difficult technological challenge in energy sector is connected with the gas micro-CHP units, dedicated to the distributed power generation. They are expected to be of high efficiency and at the same time of compact in size. Regarding the first reason, significant increase in microturbine efficiency can only be achieved by increase in the engine operating temperature. Therefore, one of the critical elements in...
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Mechanical and radiation shielding properties of concrete reinforced with boron--basalt fibers using Digital Image Correlation and X--ray micro--computed tomography
PublicationThe paper presents experimental investigations of the radiation shielding, mechanical and fracture properties of concrete reinforced with 5 kg/m3 of novel basalt fibers infused with boron oxide (BBF). However, further studies concerning other dosages i.e. 1 kg/m3, 10 kg/m3, 15 kg/m3 and 20 kg/m3 are currently carried out. Experiments with neutron source revealed that addition of BBF as a dispersed concrete reinforcement could improve...
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Strony WWW bibliotek jako element promocji i narzędzie komunikacji z użytkownikiem
PublicationW artykule przedstawiono zasady tworzenia stron WWW bibliotek, ze szczególnym uwzględnieniem bibliotek kościelnych. Zwrócono uwagę na elementy interfejsu i narzędzia służące informacji o zbiorach i usługach, a także promocji działalności biblioteki. Omówiono narzędzia z obszaru Web 2.0, służące komunikacji z użytkownikami w przestrzeni wirtualnej w czasie rzeczywistym (takie jak komunikatory, czaty, formularze zapytań) na przykładzie...
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The health impact of urban parks along waterways
PublicationWell designed parks along waterways could promote health and well-being of local inhabitants. The way the human settlements meet water bodies can influence the habits of local population. How people spend their time have significant impact on their health. For example, a team of Japanese scientists has proven that a well designed walk-able green spaces are crucial for the longevity of elderly citizens (Takano T. et al, 2002). Nature...
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Evolution of electrohydrodynamic flow of sduspended particles in a needle-to-plate negative DC corona discharge in air
PublicationCorona discharges are used for collecting dust in electrostatic precipitators (ESPs). The dust collection is mainlyrealized by the electric forces which move the ionized dust particles to the collecting electrodes. However, the presence of coronadischarge in the space between the charging and collecting electrodes in ESPs causes also the so-called ionic wind which set the gasmolecules and dust...
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Using Principal Component Analysis and Canonical Discriminant Analysis for multibeam seafloor characterisation data
PublicationThe paper presents the seafloor characterisation based on multibeam sonar data. It relies on using the integrated model and description of three types of multibeam data obtained during seafloor sensing: 1) the grey-level sonar images (echograms) of seabed, 2) the 3D model of the seabed surface which consists of bathymetric data, 3) the set of time domain bottom echo envelopes received in the consecutive sonar beams. The classification...
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SENSITIVITY OF PUBLIC PLACES IN GDAŃSK OSOWA DISTRICT
PublicationThis paper summarises the results of the research carried out at the University of Ljubljana, Faculty of Architecture, Slovenia, during the PhD visiting period of the first author from the Gdansk University of Technology, Poland, in the framework of the PhD course "Sensitive urban places", leaded by the second author. Focusing to the specific problems of the Gdansk Osowa district in Poland, this research develops the idea of sensitivity...
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Multi-nodal PWR reactor model — Methodology proposition for power distribution coefficients calculation
PublicationIn the paper the multi-nodal Pressurized Water Reactor (PWR) model called Mann’s model is presented. This models is used for modelling purposes of the heat transfer from fuel to coolant in reactor core. The authors expand widely used in literature approach by defining additional coefficients for the heat transfer model. These parameters approximate the power generation distribution in the PWR reactor core according to the to the...
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A new quaternion-based encryption method for DICOM images
PublicationIn this paper, a new quaternion-based lossless encryption technique for digital image and communication on medicine (DICOM) images is proposed. We have scrutinized and slightly modified the concept of the DICOM network to point out the best location for the proposed encryption scheme, which significantly improves speed of DICOM images encryption in comparison with those originally embedded into DICOM advanced encryption standard...
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Rapid design of miniaturised branch-line couplers through concurrent cell optimisation and surrogate-assisted fine-tuning
PublicationIn this study, the authors introduce a methodology for low-cost simulation-driven design optimisation of highly miniaturised branch-line couplers (BLCs). The first stage of their design approach exploits fast concurrent optimisation of geometrically dependent, but electromagnetically isolated cells that constitute a BLC. The cross-coupling effects between the cells are taken into account in the second stage, where a surrogate-assisted...
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Surface Plasmon-Coupled Emission of Rhodamine 110 Aggregates in a Silica Nanolayer
PublicationFirst analysis of strong directional surface plasmon-coupled emission(SPCE) of ground-state formed intermolecular aggregates of Rhodamine 110 (R110) insilica nanofilms deposited on silver nanolayers is reported. Until now, the processes ofenergy transport and its trapping due to aggregate formation have not been studied in the presence of SPCE. A new approach to multicomponent systems with weakly and strongly fluorescent centers...
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A model, design, and implementation of an efficient multithreaded workflow execution engine with data streaming, caching, and storage constraints
PublicationThe paper proposes a model, design, and implementation of an efficient multithreaded engine for execution of distributed service-based workflows with data streaming defined on a per task basis. The implementation takes into account capacity constraints of the servers on which services are installed and the workflow data footprint if needed. Furthermore, it also considers storage space of the workflow execution engine and its cost....
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Extension management of a knowledge base migration process to IPv6
PublicationThere are many reasons to deploy IPv6 protocol with IPv4 address space depletion being the most indisputable. Unfortunately, migration to IPv6 protocol seems slower than anticipated. To improve pace of the IPv6 deployment, authors of the article developed the two applications that supports the migration process. Their main purpose is to help less experienced network administrators facilitate the migration process with a particular...
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Various cases of preservation and adaptive reuse Heritage Buildings in the Port of Gdynia
PublicationThe port of Gdynia contains a diverse range of heritage assets, starting with its spatial layout which is an urban concept designed in the first half of the 1920s. It is important to point out, this historically-shaped harbor space is preserved in its general idea and still functioning in port activities. Another significant element is the structural, technological solution which was the basis for constructing the entire port area...
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A New Microwave Ceramic – Polymer Composite with 0-3 Connectivity
PublicationGoal of the present research was to fabricate and study two-phase BiNbO4//PVDF composites with 0-3 connectivity. Such composite consists of there-dimensionally connected polymer matrix loaded with dielectric ceramic particles. In the present case BiNbO4 powder acted as an active phase (dispersed phase) whereas polyvinylidene fluoride (PVDF) acted as a non-active (passive) phase (matrix). BiNbO4//PVDF composites with the volume...
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Standard of living in Poland at regional level - classification with Kohonen self-organizing maps
PublicationThe standard of living is spatially diversified and its analyzes enable shaping regional policy. Therefore, it is crucial to assess the standard of living and to classify regions due to their standard of living, based on a wide set of determinants. The most common research methods are those based on composite indicators, however, they are not ideal. Among the current critiques moved to the use of composite...
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Au–Si plasmonic platforms: synthesis, structure and FDTD simulations
PublicationPlasmonic platforms based on Au nanostructures have been successfully synthesized by directional solidification of a eutectic from Au and the substrate. In order to determine homogeneous shape and space distribution, the influence of annealing conditions and the initial thickness of the Au film on the nanostructures was analyzed. For the surface morphology studies, SEM and AFM measurements were performed. The structure of platforms...
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Single and Dual-GPU Generalized Sparse Eigenvalue Solvers for Finding a Few Low-Order Resonances of a Microwave Cavity Using the Finite-Element Method
PublicationThis paper presents two fast generalized eigenvalue solvers for sparse symmetric matrices that arise when electromagnetic cavity resonances are investigated using the higher-order finite element method (FEM). To find a few loworder resonances, the locally optimal block preconditioned conjugate gradient (LOBPCG) algorithm with null-space deflation is applied. The computations are expedited by using one or two graphical processing...
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Reliable Multi-Stage Optimization of Antennas for Multiple Performance Figures in Highly-Dimensional Parameter Spaces
PublicationDesign of modern antenna structures needs to account for multiple performance figures and geometrical constraints. Fulfillment of these calls for the development of complex topologies described by a large number of parameters. EM-driven tuning of such designs is mandatory yet immensely challenging. In this letter, a new framework for multi-stage design optimization of multi-dimensional antennas with respect to several performance...
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Analysis of compressive forces in CFGFT cylindrical pillars and their coatings using laboratory tests and metric spaces
PublicationThe article discusses compressive forces tests in composite-concrete pillars with the use of laboratory active experiment including the factors and properties of materials which have a significant impact on the test results and their repeatability. A polymer composite based on glass fiber reinforced resin with different fiber beam angles (20, 55 and 85) was used as a buffer/coat of the pole. Due to the problems with direct comparison...
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Regularized Local Multivariate Reduced-Order Models With Nonaffine Parameter Dependence
PublicationThis paper addresses a singular problem, not yet discussed in the literature, which occurs when parametric reduced-order models are created using a subspace projection approach with multiple concatenated projection bases. We show that this technique may lead to the appearance of localized artifacts in the frequency characteristics of a system, even when the reduced-order projection basis is rich enough to describe the original...
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Topological Model of an Electromagnetic Environment Inside a Ship for Electromagnetic Compatibility (EMC) Analysis
PublicationThe mutual electromagnetic (EM) interactions between electrical and electronic devices in a segmented space, such as a ship's environment, ared described. Firstly, the topological structure of a ship's segmented internal environment, which consists of many electrical screening walls (shielding planes), is presented. Then, taking into account the ship's topological structure, a general description of the EM disturbance distribution,...
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Multi-objective design optimization of antennas for reflection, size, and gain variability using kriging surrogates and generalized domain segmentation
PublicationCost-efficient multi-objective design optimization of antennas is presented. The framework exploits auxiliary data-driven surrogates, a multi-objective evolutionary algorithm for initial Pareto front identification, response correction techniques for design refinement, as well as generalized domain segmentation. The purpose of this last mechanism is to reduce the volume of the design space region that needs to be sampled in order...
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Synthesis and Properties of the Ba2PrWO6 Double Perovskite
PublicationWe report details on the synthesis and properties of barium praseodymium tungstate, Ba2PrWO6, a double perovskite that has not been synthesized before. Room-temperature (RT) powder X-ray diffraction identified the most probable space group (SG) as monoclinic I2/m, but it was only slightly distorted from the cubic structure. X-ray photoelectron spectroscopy confirmed that the initial (postsynthesis) material contained praseodymium...
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The literature review on boundary conditions of use for non-residential buildings. Educational buildings.
PublicationThis paper describes the results of qualitative and quantitative literature reviews on boundary conditions within educational buildings, emphasising the users' perspective. The studies were performed before and during the COVID-19 pandemic using Scopus, Taylor& Francis, and Web of Science databases. The boundary conditions are understood as special characteristics for use and or precondition, determining specific features of...
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Low-Cost EM-Simulation-Driven Multi-Objective Optimization of Antennas
PublicationA surrogate-based method for efficient multi-objective antenna optimization is presented. Our technique exploits response surface approximation (RSA) model constructed from sampled low-fidelity antenna model (here, obtained through coarse-discretization EM simulation). The RSA model enables fast determination of the best available trade-offs between conflicting design goals. A low-cost RSA model construction is possible through...
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Book review: Simulation-Driven Design Optimisation and Modelling for Microwave Engineering
PublicationCelem książki jest przedstawienie aktualnego stanu badań dotyczących projektowania układów mikrofalowych poprzez modelowanie i optymalizacje wspomagane symulacjami elektromagnetycznymi. Grupa międzynarodowych ekspertów zajmujących się rożnymi aspektami komputerowo wspomaganego projektowania układów mikrofalowych, podsumowuje i dokonuje przeglądu ostatnich osiągnięć w tej dziedzinie oraz przedstawia szereg praktycznych zastosowań....
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Export diversification and economic development: A dynamic spatial data analysis
PublicationThis paper contributes to the empirical literature on the relationship between “export variety” (export diversification) and economic development by relaxing the assumption of cross-country independence and allowing for spatial diffusion of shocks in observed and unobserved factors. Export variety is measured for a balanced panel of 114 countries (1992–2012) using very detailed information on their exports (HS 6-digit product level)....
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The LaPdIn 4 indide and elementary properties of the LaTIn 4 ( T = Ni, Pd, Pt) materials family
PublicationThe indium-rich intermetallic compound LaPdIn4 is reported, prepared by arc-melting and annealing at 600 C. Single crystal X-ray diffraction found the material to be orthorhombic, space group Cmcm (No. 63), with lattice parameters a ¼ 4.5462(3) Å, b ¼ 16.9208(10) Å, and c ¼ 7.3100(5) Å. This previously unreported indide is isostructural with LaNiIn4 and LaPtIn4. It is demonstrated that all three compounds in the LaTIn4 (T ¼ Ni,...
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Shape-Based Pose Estimation of Robotic Surgical Instruments
PublicationWe describe a detector of robotic instrument parts in image-guided surgery. The detector consists of a huge ensemble of scale-variant and pose-dedicated, rigid appearance templates. The templates, which are equipped with pose-related keypoints and segmentation masks, allow for explicit pose estimation and segmentation of multiple end-effectors as well as fine-grained non-maximum suppression. We train the templates by grouping examples...
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Horizontal velocity field derived from EPN and ASG-EUPOS satellite data on the example of south-western part of Poland
PublicationPresently the determination of the velocity field in the global reference frame is possible by using different space techniques and dense terrestrial networks from global to local and regional scales. However, the reliability of such determinations is strongly limited by the restricted number of unmodeled effects. Some of them are periodic (atmospheric or hydrological effects), some instantaneous (natural or man-made seismicity)...
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Towards Precise Visual Navigation and Direct Georeferencing for MAV Using ORB-SLAM2
PublicationA low accuracy of positioning using Global Navigation Satellite System (GNSS) are not meet geodetic requirements for direct images georeferencing for Unmanned Aerial Vehicle (UAV) photogrammetry. A majority of UAVs are equipped with a monocular or stereo non-metric cameras for either visual data gathering or live video feed for operator. A cheap positioning techniques used on board commercial UAVs are not that precise as geodetic...
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Non-places in the centre of the historic Main Town in Gdansk? – Design Thinking as a method of solving problems in cities
PublicationThe interiors of reconstructed extensive blocks of the historic Main Town in Gdansk are nowadays degraded areas, full of cars, with “holes” after never-finished archaeological excavations. It is not surprising that inhabitants avoid them. These are NON-PLACES. This situation prompts social movements to act. The first step towards the change was the interdisciplinary and transdisciplinary project of revitalization of one of the...
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Freehand drawing versus digital design tools in architectural teaching
PublicationThe oldest drawings resembling modern architectural designs date from the 22nd Century BC. Throughout history, the first drawings have evolved into the basic tool of the architect’s work. The exchange of information between the architect and the contractor began to take place through a drawing system, allowing to describe three-dimensional space using flat representations. With time, architectural drawings also began to resemble...
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The Touristification of Italian Historic City Centres: The Lesson for Central Europe about the Airbnb Eruption
PublicationThe unparalleled scale of the recent growth in tourism – the rise of the number of temporary visitors – could not have emerged without the impact on other socio‑economic aspects, namely, a change on the part of the destinations. Especially historic city centres are vulnerable to such an impact that could be manifested through diverse transformations of public space usage, housing market economics, availability of services, employment...
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Large Hall and Nernst responses from thermally induced spin chirality in a spin-trimer ferromagnet
PublicationThe long-range order of noncoplanar magnetic textures with scalar spin chirality (SSC) can couple to conduction electrons to produce an additional (termed geometrical or topological) Hall effect. One such example is the Hall effect in the skyrmion lattice state with quantized SSC. An alternative route to attain a finite SSC is via the spin canting caused by thermal fluctuations in the vicinity of the ferromagnetic ordering transition....
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Image transmission in UAV MIMO UWB-OSTBC system over Rayleigh channel using multiple description coding (MDC)
PublicationOrthogonal Space-Time Block Codes (OSTBC) and multiple-input-multiple-output (MIMO) communication system are new techniques with high performance that have many applications in wireless telecommunications. This chapter presents an image transfer technique for the unmanned aerial vehicle (UAV) in a UWB system using a hybrid structure of the MIMO-OSTBC wireless environment in multiple description coding (MDC) deals. MDC technique...
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Testing of the longest span soil-steel bridge in Europe – new quality in measurements
PublicationThe article describes interdisciplinary and comprehensive diagnostic tests of final bridge inspection and acceptance proposed for a soil – steel bridge made of corrugated sheets, being the European span length record holder (25.74 m). As an effect of an original concept a detailed and precise information about the structure response was collected. The load test design was based on the nonlinear numerical simulations performed by...
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An isogeometric finite element formulation for geometrically exact Timoshenko beams with extensible directors
PublicationAn isogeometric finite element formulation for geometrically and materially nonlinear Timoshenko beams is presented, which incorporates in-plane deformation of the cross-section described by two extensible director vectors. Since those directors belong to the space R3, a configuration can be additively updated. The developed formulation allows direct application of nonlinear three-dimensional constitutive equations without zero...
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The literature review on boundary conditions of use for non-residential buildings
PublicationThis paper describes the results of qualitative and quantitative literature reviews on boundary conditions within educational buildings, emphasising the users' perspective. The reviews were performed before and during the COVID-19 pandemic using Scopus, Taylor& Francis, Web of Science databases. The boundary conditions understood as special characteristics for use and or precondition, determining specific features of buildings...
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Stardust - Investigation of Microbes in the Stratosphere
PublicationThe stratospheric microbiome has been investigated several times using the methods of classical microbiology. In this experiment, we have combined them with some novel approaches including whole- metagenome amplification, Maldi TOF mass spectrometry and Sanger DNA sequencing. The results of the experiment may provide the scientists with knowledge about the mechanisms of survivability of microorganisms in stratospheric conditions...
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Design and Characterization of a Planar Structure Wideband Millimeter-Wave Antenna with Wide Beamwidth for Wearable off-body Communication Applications
PublicationThis letter presents the design of a planar single-layer wideband antenna featuring wide beamwidth has well as high and stable in-band gain. The proposed antenna is a planar monopole fed by a bottom-grounded coplanar waveguide to realize wide beamwidth in both the xz- and yz-planes. Simultaneous optimization of all adjustable antenna parameters, carried out at the full-wave electromagnetic simulation level. The constructive interference...
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Surface and interfacial anti-plane waves in micropolar solids with surface energy
PublicationIn this work, the propagation behaviour of a surface wave in a micropolar elastic half-space with surface strain and kinetic energies localized at the surface and the propagation behaviour of an interfacial anti-plane wave between two micropolar elastic half-spaces with interfacial strain and kinetic energies localized at the interface have been studied. The Gurtin–Murdoch model has been adopted for surface and interfacial elasticity....
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A Study of Cross-Linguistic Speech Emotion Recognition Based on 2D Feature Spaces
PublicationIn this research, a study of cross-linguistic speech emotion recognition is performed. For this purpose, emotional data of different languages (English, Lithuanian, German, Spanish, Serbian, and Polish) are collected, resulting in a cross-linguistic speech emotion dataset with the size of more than 10.000 emotional utterances. Despite the bi-modal character of the databases gathered, our focus is on the acoustic representation...