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Search results for: 3d printing , additive manufacturing , cubesat , fifth-generation (5 g) communication , internet-of-things , millimeter-wave antenna , passive multi-beam antennas , reconfigurable antennas , switched-beam antennas
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Dual-band antenna with improved gain for WLAN and ISM applications
PublicationIn this Letter, a dual-band antenna with an improved gain is proposed. The structure features 9.7 and 10.4 dBi gain within 2.4 GHz to 2.5 GHz and 5 GHz to 6 GHz bands, respectively. This makes it suitable for WLAN and ISM applications. The structure comprises an asymmetrical pair of radiators and slots suspended over a reflector. The antenna is optimised in a two-stage process using a trust-region-based gradient search algorithm....
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Jamming and jamming mitigation for selected 5G military scenarios
PublicationThis paper presents jamming and jamming mitigation techniques, which can be used in relation to emerging military systems based on fifth-generation (5G) technology. Nowadays, 5G technology provides incremental improvements over Long Term Evolution (LTE) networks resulting in the enhancement of civilian communications. Considering enormous possible applications of this new technology, it is feasible to use them in military utilities....
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Acoustic Streaming Induced by Periodic and Aperiodic Sound in a Bubbly Liquid
PublicationThe vortex ow which follows intense sound propagating in a bubbly liquid, is considered. The reasons for acoustic streaming are both nonlinearity and dispersion. That makes streaming especial as compared with that in a Newtonian uid. Conclusions concern the vortex ow induced in a half-space by initially harmonic or impulse Gaussian beam. The vortex ow recalls a turbulent ow with increasing in time number of small-scale vortices...
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Dissociative Electron Attachment to 5-Iodo-4-thio-2′-deoxyuridine: A Potential Radiosensitizer of Hypoxic Cells
PublicationIn the search for effective radiosensitizers for tumor cells, halogenated uracils have attracted more attention due to their large cross section for dissociation upon the attachment of low-energy electrons. In this study, we investigated dissociative electron attachment (DEA) to 5-iodo-4-thio-2'-deoxyuridine, a potential radiosensitizer using a crossed electron-molecule beam experiment coupled with quadrupole mass spectrometry....
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Screen-printed Sn-doped TiO2 nanoparticles for photocatalytic dye removal from wastewater: A technological perspective
PublicationTiO2 is widely used as a photocatalyst with a wide band gap, which limited its application. Ion doping and formulating a high-quality screen-printing paste enhance its features. However, the printability of objects for advanced application seems essential nowadays. In this research, the Sn-doped TiO2 nanoparticles were prepared through a sol-gel method followed by calcination at various temperatures of 450 °C, 550 °C, 650 °C, 750...
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Study of the Effectiveness of Model Order Reduction Algorithms in the Finite Element Method Analysis of Multi-port Microwave Structures
PublicationThe purpose of this paper is to investigate the effectiveness of model order reduction algorithms in finite element method analysis of multi-port microwave structures. Consideration is given to state of the art algorithms, i.e. compact reduced-basis method (CRBM), second-order Arnoldi method for passive-order reduction (SAPOR), reduced-basis methods (RBM) and subspace-splitting moment-matching MOR (SSMM-MOR)
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Quality Analysis of Audio-Video Transmission in an OFDM-Based Communication System
PublicationApplication of a reliable audio-video communication system, brings many advantages. With the spoken word we can exchange ideas, provide descriptive information, as well as aid to another person. With the availability of visual information one can monitor the surrounding, working environment, etc. As the amount of available bandwidth continues to shrink, researchers focus on novel types of transmission. Currently, orthogonal frequency...
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Usage of parametric echosounder with emphasis on buried object searching.
PublicationThe purpose of this article is to present the results of investigation to search for buried objects. The paper will contain echograms and other means of visualization from buried pipe placed between area of W?adys?awowo and gas platform and interesting in terms of the number of small and medium-sized unidentified objects found in the muddy bottom at different depths localized in the Gulf of Puck - results will be presented also...
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Asynchronous Method of Simultaneous Object Position and Orientation Estimation with Two Transmitters
PublicationThis paper proposes an object location method for all types of applications, including the Internet of Things. The proposed method enables estimations of the position and orientation of an object on a plane or in space, especially during motion, by means of location signals transmitted simultaneously from two transmitters placed on the object at a known distance from each other. A mathematical analysis of the proposed method and...
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Impact of Spatial Noise Correlation on Bearing Accuracy in DIFAR Systems
PublicationDIFAR type underwater passive systems are one of the more commonly used tools for detecting submarines. At the design stage, which usually uses computer simulations, it is necessary to generate acoustic noise of the sea. It has been shown that correlating noise significantly reduces these errors compared to the assumption that noise is uncorrelated. In addition, bearing errors have been shown to be the same in systems with a commonly...
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Enhancing Seismic Performance of Semi-rigid Connection Using Shape Memory Alloy Bolts Considering Nonlinear Soil–Structure Interaction
PublicationSteel Moment-Resisting Frames (SMRFs) have their lateral resistance for their rigid connections, while real conditions have shown that the rigidity of a connection depends on the bolts and the end-plate thickness, which may not provide the assumed rigidity in design process. In this research, the main goal is to enhance the semi-rigid connections using shape memory alloy (SMA) bolts and explore their effects on the seismic limit-state...
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Acoustic field and the entropy mode induced by it in a waveguide filled with some non-equilibrium gases
PublicationThe non-linear propagation of an acoustic beam in a rectangular waveguide is considered. The medium of sound propagation, is a gas where thermodynamically non-equilibrium processes take place: such as exothermic chemical reactions or excitation of vibrational degrees of a molecule’s freedom. The incident and reflected compounds of the acoustic field do not interact in the leading order in the case of periodic weakly nonlinear sound...
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Simulator for Performance Evaluation of ASON/GMPLS Network
PublicationThe 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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Paradygmat informacyjny projektowania systemów wytwórczych nowej generacji
PublicationW niniejszym rozdziale pokazano informacyjny paradygmat projektowania i eksploatacji elastycznych systemów produkcyjnych na przykładzie róznych modeli systemów nowej generacji NGMS (Next Generation Manufacturing System). Na bazie modeli BMS (Bionc Manufacturing System)HMS (Holonie Manufacturing System), FFMS (Fraktal Factory Maufacturing System) dokonano analizy porównawczej wybranych rozwiązań w przedmiotowym obszarze, formułując...
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Three-dimensional modeling and automatic analysis of the human nasal cavity and paranasal sinuses using the computational fluid dynamics method
PublicationPurpose The goal of this study was to develop a complete workflow allowing for conducting computational fluid dynam- ics (CFD) simulation of airflow through the upper airways based on computed tomography (CT) and cone-beam computed tomography (CBCT) studies of individual adult patients. Methods This study is based on CT images of 16 patients. Image processing and model generation of the human nasal cavity and paranasal sinuses...
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The complexity of bicriteria tree-depth
PublicationThe tree-depth problem can be seen as finding an elimination tree of minimum height for a given input graph G. We introduce a bicriteria generalization in which additionally the width of the elimination tree needs to be bounded by some input integer b. We are interested in the case when G is the line graph of a tree, proving that the problem is NP-hard and obtaining a polynomial-time additive 2b-approximation algorithm. This particular...
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Integrating Digital Twin Technology Into Large Panel System Estates Retrofit Projects
PublicationAs sustainability is now a standard for the proposed developments, the focus ought to be shifted towards the existing buildings and, among them, the worldwide stock of large panel system (LPS) buildings. Major upgrades and retrofits were done to some of the LPS estates in Germany and France, but a leading sustainable way must still be developed for LPS buildings in Eastern European countries, where apartments in those half‐a‐century‐old...
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Wykorzystanie narzędzi pracy zdalnej w działaniach Koła Naukowego Konstruktorów Pojazdów
PublicationNiniejszy artykuł stanowi opis działalności Koła Naukowego Konstruktorów Pojazdów, w którego działaniach wykorzystywane są nowoczesne narzędzia pracy zdalnej. Dzięki takiemu podejściu, możliwe staje się wyeliminowanie niedogodnień, z którymi borykano się stosując standardowe, starsze podejście do realizacji zadań projektowych w jednostkach badawczo-rozwojowych. Podane przykłady ilustrują, w jaki sposób powszechny obecnie dostęp...
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Sensorless control of five-phase induction machine supplied by the VSI with output filter
PublicationIn this paper, a novel sensorless control structure based on multi-scalar variables is proposed. The tatic feedback control law is obtained by using the multi-scalar variables transformation, where the multi-scalar variables approach allows a full linearization of the nonlinear system. The control system could be described as “optimized” because of the minimized number of controllers. Furthermore, control system is divided into...
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Salinity enhances high optically active L-lactate production from co-fermentation of food waste and waste activated sludge: Unveiling the response of microbial community shift and functional profiling
PublicationLactic acid (LA), a versatile platform molecule, can be fermented from organic wastes, such as food waste and waste activated sludge. In this study, an efficient approach using salt, a component of food waste as an additive, was proposed to increase LA production. The LA productivity was increased at 10 g NaCl/L and optical pure L-lactate was obtained at 30 g NaCl/L. The enhancement of LA was in accordance with the increased solubilization...
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Cheap Cancellation of Strong Echoes for Digital Passive and Noise Radars
PublicationThe problem of cancellation of strong, potentially nonstationary,echoes in noise radars and passive radars utilizing digitaltransmissions is considered. The proposed solution is a multi-stage procedure.Initial clutter estimates, obtained using the least mean squares(LMS) algorithm, are refined using specially designed filters, "matched"to spectral densities of targets and clutter. When the postprocessing filtersare noncausal, the...
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Effect of manufacturing errors of the pad sliding surface on the performance of the hydrodynamic thrust bearing
PublicationIn the present study, investigation of the effect of manufacturing errors on the performance of large tilting pad thrust bearings has been performed, following a CFD-based Thermohydrodynamic analysis of a single pad. A 3D model has been generated, including the pad, the lubricant film and the corresponding part of the collar. The pad has been assumed to be deformed about the pivot point, due to thrust loading. Manufacturing errors...
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A geophysical, geochemical and microbiological study of a newly discovered pockmark with active gas seepage and submarine groundwater discharge (MET1-BH, central Gulf of Gdańsk, southern Baltic Sea)
PublicationHigh-resolution bathymetric data were collected with a multi-beam echosounder in the southern part of the Baltic Sea (region MET1, Gulf of Gdańsk) revealing the presence of a 10 m deep and 50 m in diameter pockmark (MET1-BH) on the sea bottom (78.7 m). To date, no such structures have been observed to reach this size in the Baltic Sea. The salinity of the near-bottom water in the pockmark was about 2 PSU (about 31.22 mmol/l...
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An investigation of microstructural basis for corrosion behavior of Al-CNT composites fabricated by SPS
PublicationIn this research effect of the addition of multi-wall carbon nanotubes (MWCNTs) as additive powder on microstructure and corrosion behavior of fabricated Al-CNT composites was studied. The aluminum powder and CNTs were mixed with high energy planetary ball-mill. It is observed that by increasing milling time, the uniformity of CNTs on aluminum matrix and consequently corrosion resistance of Al-CNT composite is increased. On the...
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Acoustic radar employing particle velocity sensors
PublicationA concept, practical realization and applications of a passive acoustic radar to automatic localization, tracking of sound sources were presented in the paper. The device consist of the new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. Contrary to active radars, it does not emit the scanning beam but after receiving surroundings sounds it provide information about the...
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Analysis of IMS/NGN call processing performance using G/G/1 queuing systems approximations
PublicationThe paper concerns the Next Generation Network (NGN), which is standardized for distribution of multimedia services based on the IP Multimedia Subsystem (IMS). To guarantee quality, accurate traffic models of IMS/NGN should be proposed. In the paper we compare results obtained with our analytical and simulation model of a single IMS/NGN domain, where various queuing systems are used in the analytical model (M/G/1 and approximations...
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Wybrane aspekty zachowań internautów oraz rozwój komunikacji marketingowej w Internecie - Polska na tle innych krajów europejskich
PublicationCelem artykułu jest zaprezentowanie różnic w zachowaniach klientów on-line oraz rozwoju komunikacji marketingowej w Internecie. W opracowaniu powołano się na wyniki badań internautów przeprowadzonych w Polsce i w innych krajach Europy. Przybliżono w nim najbardziej charakterystyczne cechy i zachowania użytkowników Internetu. Oprócz tego, w artykule ukazano istotę podejścia inbound marketing w kreowaniu wartościowych treści z punktu...
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A navigation device utilizing body communication channel for mobile wearable systems
PublicationA novel touch sensor utilizing a body communication technology is presented in the paper. The proposed device accepts orders (gestures) only from a person wearing it. Moreover, when comparing it to a similar, however an optical one, it appears as a less power consumable. Preliminary results of its properties examination are presented and discussed. Additionally, the developed sensor allows to measure a human body the electrical...
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KOLMOGOROV EQUATION SOLUTION: MULTIPLE SCATTERING EXPANSION AND PHOTON STATISTICS EVOLUTION MODELING
PublicationWe consider a formulation of the Cauchy problem for the Kolmogorov equation which corresponds to a localized source of particles to be scattered by a medium with a given scattering amplitude density. The multiple scattering amplitudes are introduced and the corresponding series solution of the equation is constructed. We investigate the integral representation for the first series terms, its estimations and values of the photon...
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Wzbudzone siły wewnętrzne : skutki upr0szczonego modelowania zakrzywionej estakady sprężonej
Publicationthe paper presents problems, which were encountered during the construction of a southern road bypass of city gdansk. after prestressing and removing formwork, the contractor spotted, that some of outer bearings are detached. performed analysis showed that, this situation was caused by the usage of a simplified, straight beam model during design phase. the paper shows the influence of a curved in plane prestressed system on internal...
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Communication Platform for Evaluation of Transmitted Speech Quality
PublicationA voice communication system designed and implemented is described. The purpose of the presented platform was to enable a series of experiments related to the quality assessment of algorithms used in the coding and transmitting of speech. The system is equipped with tools for recording signals at each stage of processing, making it possible to subject them to subjective assessments by listening tests or, objective evaluation employing...
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Using Fast Frequency Hopping Technique to Improve Reliability of Underwater Communication System
PublicationAcoustic underwater communication systems designed to work reliably in shallow coastal waters must overcome major limitations such as multipath propagation and the Doppler effect. These restrictions are the reason for the complexity of receivers being built, whose task is to decode a symbol on the basis of the received signal. Additional complications are caused by the low propagation speed of the acoustic wave in the water and...
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The New 3D Printed Left Atrial Appendage Closure with a Novel Holdfast Device: A Pre-Clinical Feasibility Animal Study
PublicationMany patients undergoing cardiac surgery have risk factors for both atrial fibrillation and stroke. The left atrial appendage (LAA) is the primary site for thrombi formation. Therefore LAA occlusion devices should be tested for their ability to reduce future cerebral ischemic events in patients with high-risk of haemorrhage. The aim of this study was to evaluate the safety and feasibility of a novel left atrial appendage exclusion...
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Review of Diameter protocol implementations for realization of communication in NGN networks
PublicationIn the paper Diameter protocol as well as its applications in the context of Next Generation Network (NGN) are described. Diameter message content and Attribute-Value Pairs (AVPs) concept are presented. Critical review of open source Diameter implementations is carried out. The performed analysis takes into consideration programming language, availability, support and documentation aspects. Basing on the review project fulfilling...
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Taxonomy of Schemes for Resilient Routing
PublicationThis chapter provides a taxonomy of schemes for resilient routing followed by a discussion of their application to contemporary architectures of communication networks. In particular, a general classification of schemes for resilient routing is first presented followed by a description of the reference schemes for IP networks. The chapter in its later part focuses on the representative techniques of resilient routing for a multi-domain...
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Low-Power WSN System for Honey Bee Monitoring
PublicationThe paper presents a universal low-power system for biosensory data acquisition in scope of bees monitoring. We describe the architecture of the system, energy-saving components as well as we discuss the selection of used sensors. The work focuses on energy optimization in a scope of wireless communication. A custom protocol was implemented, which is the basis for presented energy-efficient devices. Data exchange process during...
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Solid and liquid fractionation of sugarcane and Agave bagasse during ozonolysis and enzymatic hydrolysis: Impact on biohydrogen and biogas production
PublicationSustainable and cost-efficient lignocellulosic biomass-to-energy bioprocesses require assessing the main components released during biomass fractionation. This study assessed the mesophilic biochemical potential of biohydrogen (BHP) and methane production (BMP) from sugarcane bagasse (SCB) and cooked (CAB) and uncooked (UAB) Agave bagasse. A systematic comparative analysis was performed for the liquid and solid fractions derived...
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On Nonlinear Bending Study of a Piezo-Flexomagnetic Nanobeam Based on an Analytical-Numerical Solution
PublicationAmong various magneto-elastic phenomena, flexomagnetic (FM) coupling can be defined as a dependence between strain gradient and magnetic polarization and, contrariwise, elastic strain and magnetic field gradient. This feature is a higher-order one than piezomagnetic, which is the magnetic response to strain. At the nanoscale, where large strain gradients are expected, the FM effect is significant and could be even dominant. In...
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Problematyka konstrukcyjna zabytkowego obiektu przywracanego do użytkowania na przykładzie kamienicy przy ul. Staromiejskiej w Olsztynie = Structural aspects in restoring historical buildings for re-use: the case of a tenement building on Staromiejska Street in Olsztyn
PublicationThe paper discusses the issue of introducing structural changes into a historical building referring to the example of conservation work carried out in the tenement house at 6 Staromiejska in Olsztyn. Building work involved a general renovation. The paper reviews actions carried out in the restoration work, including strengthening and deepening of the foundations, introducing a post and beam system, and putting...
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Sounding of Layered Marine Bottom - Model Investigations
PublicationThe necessary actions connected with interpretations of examining of physical properties of sea bottom structure is developing of proper procedure of modeling of the layered structure. The implementation of the acoustic waves for the determination of seabed stratification requires a precise diagnosis of the topic from both the theoretical and practical side. Little differences between the parameters of sediments, as well as irregular...
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Circular polarization diversity implementation for correlation reduction in wideband low-cost multiple-input-multiple-output antenna
PublicationIn this paper, a multiple-input-multiple-output (MIMO) antenna featuring circular polarization diversity, and designed on a common coplanar ground is presented. The proposed antenna design utilizes a coplanar waveguide (CPW) feeding technique with three parallel coplanar ground planes, and two feedlines in-between. For circular polarization (CP), quasi-loops are created by etching slots on the outermost ground planes. With this...
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Optimizing the computation of a parallel 3D finite difference algorithm for graphics processing units
PublicationThis paper explores the possibilities of using a graphics processing unit for complex 3D finite difference computation via MUSTA‐FORCE and WENO algorithms. We propose a novel algorithm based on the new properties of CUDA surface memory optimized for 2D spatial locality and compare it with 3D stencil computations carried out via shared memory, which is currently considered to be the best approach. A case study was performed for...
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Investigation of environmental influences to the precise GNNS solutions
PublicationThe results presented in this paper concern investigation of environmental influences to GNNS coordinates on the example of ASG-EUPOS network. The problem of the impact of environmental effects is crucial for observing gravity. Satellite systems are not as susceptible to changes in local hydrology or atmospheric effects, although significant influences are clearly visible in the change of coordinates. The authors analyzed daily...
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The Impact Of The Selected Parameters Of Fdm Manufacturing Technology On Tribological Performance Of Abs–Steel Pair Under Dry Friction
PublicationThe paper presents the result of tribological test of ABS and steel samples sliding under dry friction. Polymeric samples were manufactured of ABS material using FDM technology. Testing was carried out in unidirectional sliding in a ring-on-flat contact in a PT-3 tribometer. The scope of tested parameters included volumetric and mass wear, the friction coefficient, and polymeric specimen temperature. Polymeric specimens used in...
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Electromagnetic Simulations with 3D FEM and Intel Optane Persistent Memory
PublicationAbstract—Intel Optane persistent memory has the potential to induce a change in how high-performance calculations requiring a large system memory capacity are conducted. This article presents what this change may look like in the case of factorization of large sparse matrices describing electromagnetic problems arising in the 3D FEM analysis of passive highfrequency components. In numerical tests, the Intel oneAPI MKL PARDISO was...
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Low energy elastic electron scattering from benzonitrile (C6H5CN)
PublicationWe present experimental differential elastic scattering cross sections (DCSs) for low energy electron scattering from benzonitrile along with integral and momentum-transfer cross sections that are determined from these DCSs. The measurements of DCSs are obtained using the relative flow method with helium as the standard gas, in a crossed electron-molecular gas beam arrangement. Our measurements are made at incident electron energies...
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Cavitation Erosion of P110 Steel in Different Drilling Muds
PublicationThe P110 steel specimens were subjected to ultrasonic cavitation erosion in different compositions of drilling muds and surfactant additive. The test procedure was based on ASTM-G-32 standard recommendations. API 5CT-P110 steel is used for pipes in oil and gas industry. The harsh environment and high velocity of flows poses corrosive and erosive threat on materials used there. The composition of drilling fluid influences its rheological...
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FEA analysis of the multicell piezoelectric motor
PublicationThe presented paper concerns a design, modeling and chosen tests of the prototype multicell piezoelectric motor (MPM). The principle of operation based on three independent traveling wave actuators is presented. The main materials and technologies used in the fabrication process are described. The structure of the motor is modeled using static and modal FEM analysis. The process of traveling wave generation in the MPM structure...
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DETECTION OF DEBONDING IN STEEL BARS EMBEDDED IN CONCRETE USING GUIDED WAVE PROPAGATION
PublicationThe paper presents a non-destructive diagnostic technique based on guided wave propagation phenomenon used to assess the adhesive bonding between a steel bar and a concrete cover. Double-layered cylindrical specimens with different levels of debonding and its location were investigated. The influence of bonding length on the excitation of multiple modes of longitudinal guided waves was analysed. Numerical simulations of guided...
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Resilient Routing in Communication Networks
PublicationThis important text/reference addresses the latest issues in end-to-end resilient routing in communication networks. The work highlights the main causes of failures of network nodes and links, and presents an overview of resilient routing mechanisms, covering issues related to the Future Internet (FI), wireless mesh networks (WMNs), and vehicular ad-hoc networks (VANETs). For each of these network architectures, a selection of...