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Search results for: BANANA-SHAPED MESOGENS
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Beta-Galactosidases of Pseudoalteromonas sp. – Characteristics and application for lactose hydrolysis and galactopyranosides synthesis
PublicationBeta-galactosidase [EC 3.2.1.23] is an enzyme that catalyzes the hydrolysis of O-glycosidic linkages in galactosides. It has biotechnological applications in the dairy industry for the production of milk with a low content of lactose and galactooligosacharides for use in healthy food. The transgalactosylation activity of beta-galactosidase can be used in the synthesis of alkyl galactopyranosides. Due to the fact that conditions of...
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Deregulacja polskiego rynku pracy
PublicationHistorycznie ukształtowana regulacja rynku pracy związana jest z jego infrastrukturą organizacyjno-prawną, tzn. przepisami dotyczącymi płac, czasu pracy i ochrony stosunku pracy. W opinii zwolenników deregulacji utrudnia ona elastyczne dostosowywanie się do rozmiarów zatrudnienia w zależności od zaistniałej sytuacji gospodarczej, powodując wzrost bezrobocia strukturalnego i wzrost kosztów pracy. Deregulacja rynku pracy związana...
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ZNACZENIE ŹRÓDEŁ POCZUCIA SAMOSKUTECZNOŚCI U POCZĄTKUJĄCYCH PRZEDSIĘBIORCÓW – RAPORT Z BADAŃ
PublicationPoczucie samoskuteczności w sposób istotny wpływa na zachowanie ludzi sprawiając, że stają się oni bardziej wytrwali w działaniu i stawiają sobie ambitne cele. Poczucie samoskuteczności powstaje pod wpływem doświadczeń jednostki, a jego poziom jest możliwy do kształtowania. Zdaniem Bandury (1997) istnieją cztery źródła poczucia samoskuteczności, czyli poprzednie doświadczenie, pobudzenie fizjologiczne, obserwacja innych oraz perswazja....
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Temperature Measurements at Tyre Tread Rubber on Sandpaper Oscillatory Sliding Contacts Using Acicular Grindable Thermocouples
PublicationThe tribological performance of tyre–road contacts depends crucially on the contact temperature. This study investigates the reliability and accuracy of acicular grindable thermocouples possessing an original needle-shaped wearable part as applied to measuring temperature at the oscillatory sliding contact between a rubber tyre tread sample and a sandpaper. A linear oscillatory tribometer is used to imitate the sliding phase of...
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Dispersive Delay Structures With Asymmetric Arbitrary Group-Delay Response Using Coupled-Resonator Networks With Frequency-Variant Couplings
PublicationThis article reports the design of coupled-resonatorbased microwave dispersive delay structures (DDSs) with arbitrary asymmetric-type group delay response. The design process exploits a coupling matrix representation of the DDS circuit as a network of resonators with frequency-variant couplings (FVCs). The group delay response is shaped using complex transmission zeros (TZs) created by dispersive cross-couplings. We also present an...
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Assessment of the devulcanization process of EPDM waste from roofing systems by combined thermomechanical/microwave procedures
PublicationEthylene-propylene-diene rubber (EPDM) is a elastomer widely used in common industrial applications. EPDM can be shaped into sheets and employed as isolating material for roofing systems. In this study, scraps of EPDM from commercial, industrial and residential roofing systems were treated by combined thermo-mechanical and microwave devulcanization processes including peroxide of benzoyl (BPO). The devulcanized EPDM (Dev-EPDM)...
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Design of Compact and Wideband Groove Gap Waveguide-Based Directional Couplers
PublicationThis paper proposes a compact cross-shaped groove gap waveguide structure for creating wideband and compact directional couplers with different coupling levels. Groove gap waveguide technology is applied to overcome fabrication challenges of printed and hollow waveguide structures in high frequency bands. The validity of the novel concept is demonstrated through the design and evaluation of several compact broadband directional...
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Nitrogen oxides removal from hydrogen flue gas using corona discharge in marine boilers: Application perspective
PublicationThis paper focuses on the combustion of hydrogen in boilers, as it appears to be a more effective method than using fuel cells for heating purposes due to higher boiler efficiency. One of the main disadvantages of hydrogen combustion in air is NOx formation. Therefore, the authors decided to introduce corona discharge as an inno- vative technique to clean hydrogen flue gas by effectively reducing NOx levels. The method involves...
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Globalisation and world economic poverty: The significance of hidden dimensions
PublicationThe aim of our research is to examine how individual dimensions of globalization affect economic poverty in the World. for this, regression models are estimated with FGT0 or FGT1 poverty measures as dependent variables and KOF indices of globalization as despendent variables. The poverty indices are estimated for 119 countries' income didtributions assuming log-normality and using Gini estimates from the WID2 database and GDP/capita...
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Functionalization of indium-tin-oxide electrodes by laser-nanostructured gold thin films for biosensing applications
Publicationof a relatively large area formed by pulsed laser nanostructuring of thin gold films arereported and discussed. The SEM inspection of modified electrodes reveals the presence of the nearlyspherical and disc-shaped particles of dimensions in the range of 40–120 nm. The NP-array geometry canbe controlled by selection of the laser processing conditions. It is shown that particle size and packingdensity of the array are important factors...
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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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Improvement of ships seakeeping performance by application of the full-scale cfd simulations
PublicationThe ship’s fuel economy is increasingly important. The paper presents the effect of redesigning a case study ship for increasing seakeeping performance. Selected wave parameters reflect very difficult operational conditions existing on the North Sea and the Baltic Sea. The analyzed variants of a case study ship represent the latest developments of modern hull forms. The concepts similar to V-shaped bulbous bow, X-bow, X-aft, B-bow...
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Microfluidic SIW-Based Tunable Self-Diplexing Antenna for Sub-6 GHz Band Applications
PublicationThis work introduces a novel frequency tunable self-diplexing antenna (SDA) design based on substrate integrated waveguide (SIW) technology. A modified A-shaped slot is employed on the cavity’s top plane, which is excited by two independent 50 Ω microstrip feed lines to operate at each resonant frequency. The frequency flexibility of the proposed antenna allows for fine-tuning at each resonance frequency. The frequency flexibility...
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Shielded HMSIW-Based Self-Triplexing Antenna With High Isolation for WiFi/WLAN/ISM Band
PublicationThis article presents a novel design of a miniaturized self-triplexing antenna (STA) based on the shielded half-mode substrate integrated waveguide (S-HMSIW) for WiFi/WLAN/ISM-band applications. The S-HMSIW is constructed by assembling one row of vias and an open slot at the open-ended side of the conventional HMSIW. This configuration increases the quality factor and minimizes unwanted radiation loss, which allows for achieving...
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A city is not a tree: a multi-city study on street network and urban life
PublicationChristopher Alexander, a British-American scholar, differentiated an old (natural) city from a new (planned) one by structure. The former resembles a “semilattice”, or a complex system encompassing many interconnected sub-systems. The latter is shaped in a graph-theoretical “tree”, which lacks the structural complexity as its sub-systems are compartmentalized into a single hierarchy. This structural distinction explains why, or...
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Experimental investigation of Steel–Concrete–Polymer composite barrier for the ship internal tank construction
PublicationTransportation of dangerous cargo by ships demands ensuring an appropriate protection level in case of an accident. Two of the most dangerous accident types resulting in an oil spill are grounding and ship to ship collision. The article presents results of research on a new composite construction for a ship hull that increases structural safety during collision. The concept of semi-elastic Steel–Concrete–Polymer structure is presented....
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Recent Achievements in Constitutive Equations of Laminates and Functionally Graded Structures Formulated in the Resultant Nonlinear Shell Theory
PublicationThe development of constitutive equations formulated in the resultant nonlinear shell theory is presented. The specific features of the present shell theory are drilling rotation naturally included in the formulation and asymmetric measures of strains and stress resultants. The special attention in the chapter is given to recent achievements: progressive failure analysis of laminated shells and elastoplastic constitutive relation...
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Improvement of ships seakeeping performance by application of the Full-scale CFD simulations – case study
PublicationThe ship’s fuel economy is increasingly important. The paper presents the effect of redesigning a case study ship for increasing seakeeping performance. Selected wave parameters reflects very difficult operational con-ditions existing on the North Sea and the Baltic Sea. The analyzed variants of a case study ship represent the latest developments of modern hull forms. The concepts similar to V-shaped bulbous bow, X-bow, X-aft,...
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Gdańsk’s Cultural Heritage. The City Centre District and Municipal Historical Policy
PublicationThe current municipal historical policy of Gdańsk focuses on two major museum projects purported to be a unique embodiment of the city’s cultural heritage. Their underlying narrative, which is told from the European perspective, is based on two great events of the 20th century and seems to disregard the cultural heritage recorded in the urban structure of the city centre. However, it is precisely this urban structure that exerts...
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High-density Polyethylene - Expanded Perlite Composites: Structural Oriented Analysis of Mechanical and Thermomechanical Properties
PublicationAs part of this work, research was carried out on the effect of the addition of expanded perlite (PR) on the mechanical and thermomechanical properties of high-density polyethylene (PE) composites. Composites containing from 1 to 10 wt% of the inorganic filler were produced. Polyethylene-based composites manufactured by twin-screw extrusion and formed in the compression molding process were subjected to mechanical, thermomechanical,...
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Preparation and evaluation of 1,3-alternate 25,27-bis-(pentafluorobenzyloxy)-26,28-bis-(3-propyloxy)-calix[4]arene-bonded silics gel high performance liquid chromatography stationary phase
PublicationA 1,3-alternate 25,27-bis-(pentafluorobenzyloxy)-26,28-bis-(3-propyloxy)-calix[4]arene-bonded silica gel stationary phase (CalixBzF10) was synthesized, structurally characterized, and used as a selector in liquid chromatography. The selectivity study of this phase was done by using fluorine-containing compounds (fluorobenzenes, fluoro-pyrimidine bases), as well as non-fluorinated analytes (non-steroidal anti-inflammatory drugs,...
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The effect of hybridization of fire retarded epoxy/flax-cotton fiber laminates by expanded vermiculite: Structure-property relationship study
PublicationThe study describes the hybridization of epoxy/flax-cotton (EP/FF) composites containing ammonium polyphosphate (APP) with micrometric expanded vermiculite (VMT) (1–10 wt%). The efficiency of hybridization of flame retarded epoxy/flax-cotton composites was assessed by performing static tensile and flexural strength evaluation, supplemented by impact strength measurements of the composites. Moreover, thermal and thermomechanical...
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Badania eksperymentalne strefy przypodporowej żelbetowych belek częściowo sprężonych
PublicationThis project refers to the study the shear zone, under full and partial prestressing in comparison to beams with passive reinforcement.For comparison, variable parameters have been determined:- a/d (from 1,5 to 3,5) - it's shear span to effective depth of the beam . Assuming constant geometrical quantities, "a" is variable.- 26 beams had no vertical shear reinforcement, and the other 26 had closed stirrups.- prestressing intensity...
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Dome over the Gdynia seaport building
PublicationThe paper presents the description of structure and the selected problems of the technical condition, as well as the strength analysis of the thin-walled reinforced concrete shell which has been making a covering of the main hall of the Gdynia Seaport Building through the last 80 years. The rectangle projection of four single curvature shells of the dome was shaped out of mutual perpendicular intersection of two cylindrical shells. The...
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Using terrestrial laser scanning in inventorying of a hybrid constructed wetland system
PublicationThe goal of this paper was to evaluate the possibility of using terrestrial laser scanning (TLS) for inventorying of a hybrid constructed wetland (CW) wastewater treatment plant. The object under study was a turtle-shaped system built in 2015 in Eastern Poland. Its main purpose is the treatment of wastewater from theMuseumand Education Centre of Polesie National Park. The study showed that the CW system had been built in compliance...
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On local buckling of cold-formed channel members
PublicationThe paper deals with local buckling of the compressed flanges of cold-formed thin-walled channel beams subjected to pure bending or axially compressed columns. Arbitrarily shaped flanges of open cross-sections and the web-flange interactions are taken into account. Buckling deformation of a beam flange is described by displacement related to torsion of the flange about the line of its connection with the web. Total potential energy...
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Sustainable investing exchange-traded funds: US and European market
PublicationThe key aim of the paper is to examine the diffusion of the sustainable investing exchange-traded funds (ETFs) on the European and US ETFs markets, with the special focus on the market shares of sustainable investing and conventional funds. The model of diffusion of innovation (logistic growth model) is applied. Monthly data on the assets of ETFs in the time period of 2006-2017 are used. Increasing assets of sustainable investing...
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Interplay between Aryl···Perfluoroaryl and Hydrogen Bonding Interactions in Cocrystals of Pentafluorophenol with Molecules of Trigonal Symmetry
PublicationCocrystals of seven star-shaped triaryl compounds with pentafluorophenol (pfp) were prepared and structurally characterized by the single-crystal X-ray diffraction method. Cocrystallization of pfp with planar (or almost planar) compounds gave six 3:1 molecular complexes with well-defined layered structures. The layers are composed of alternating pfp3 trimers, linked by hydrogen bonding, and triaryl molecules held together in planes...
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Do mistakes acceptance foster innovation? Polish and US cross-country study of tacit knowledge sharing in IT
PublicationAbstract Purpose – This study aims to understand and compare how the mechanism of innovative processes in the information technology (IT) industry – the most innovative industry worldwide – is shaped in Poland and the USA in terms of tacit knowledge awareness and sharing driven by a culture of knowledge and learning, composed of a learning climate and mistake acceptance. Design/methodology/approach – Study samples were drawn from...
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Applying molecular dynamics simulation to take the fracture fingerprint of polycrystalline SiC nanosheets
PublicationGraphene-like nanosheets are the key elements of advanced materials and systems. The mechanical behavior of the structurally perfect 2D nanostructures is well documented, but that of polycrystalline ones is less understood. Herein, we applied molecular dynamics simulation (MDS) to take the fracture fingerprint of polycrystalline SiC nanosheets (PSiCNS), where monocrystalline SiC nanosheets (MSiCNS) was the reference nanosheet....
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Biomechanical properties of 3D-printed bone models
PublicationBone lesions resulting from large traumas or cancer resections can be successfully treated by directly using synthetic materials or in combination with tissue engineering methods (hybrid). Synthetic or hybrid materials combined with bone tissue’s natural ability for regeneration and biological adaptation to the directions of loading, allow for full recovery of its biological functions. Increasing interest in new production methods...
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The retrofitting of ships by applying retractable bow hydrofoils: a case study
PublicationIncreasing environmental requirements and a relatively long ship life of 30 years mean more attention is needed to retrofit existing ships. One possibility is using hydrofoils to reduce the ship’s resistance and improve comfort and safety in rough sea conditions. This study investigates the influence of retractable bow hydrofoils on the seakeeping performance and operational conditions of a selected case study vessel (V-shaped...
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Earthquake-Induced Pounding Between Asymmetric Steel Buildings
PublicationEarthquake-induced pounding between buildings has been the subject of numerous numerical and experimental studies in the resent years. The phenomenon may cause severe damage to structural elements as well as may also lead to the total collapse of colliding structures. A major reason leading to pounding between adjacent, insufficiently separated buildings results from the differences in their dynamic properties. The aim of this...
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Finite-element analysis of a base-isolated multi-storey steel building under seismic motions
PublicationNumerical simulation of the seismic behaviour of a multi-storey steel building, both fixed-base and base-isolated, under the 1940 El Centro earthquake was performed in this paper. The analyzed 4-storey building was decoupled from the shaking ground with the Polymeric Bearings, which can be considered a proposal of a new seismic isolation system. It consists of rectangular-shaped blocks made of a specially prepared flexible polymeric...
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Nonlinear Modeling in Time Domain Numerical Analysis of Stringed Instrument Dynamics
PublicationMusical instruments are very various in terms of sound quality with their timbre shaped by materials and geometry. Materials' impact is commonly treated as dominant one by musicians, while it is unclear whether it is true or not. The research proposed in the study focuses on determining influence of both these factors on sound quality based on their impact on harmonic composition. Numerical approach has been chosen to allowed independent...
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Low-Dimensional Magnetic Semimetal Cr0.65Al1.35Se3
PublicationWhile exploring novel magnetic semiconductors, the new phase Cr0.65Al1.35Se3 was discovered and characterized by both structural and physical properties. Cr0.65Al1.35Se3 was found to crystallize into orthorhombic CrGeTe3-type structure with space group Pnma (no. 62). Vacancies and mixed occupancies were tested, and the results show that one of the 4c sites accommodates a mixture of Cr and Al atoms, while the other 4c site is fully...
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Travel agents and destination management organizations: eLearning as a strategy to train tourism trade partners.
PublicationThis article offers an overview of the existing online courses run by national destination management organizations (DMOs) in order to better equip travel agents and tour operators in the sales activities of the tourism destinations. These online courses represent one of the B2B offers by DMOs and an interesting opportunity for travel agents, who are trying to find their identity and competitive advantage within the context of...
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Thermal buckling of functionally graded piezomagnetic micro- and nanobeams presenting the flexomagnetic effect
PublicationGalerkin weighted residual method (GWRM) is applied and implemented to address the axial stability and bifurcation point of a functionally graded piezomagnetic structure containing flexomagneticity in a thermal environment. The continuum specimen involves an exponential mass distributed in a heterogeneous media with a constant square cross section. The physical neutral plane is investigated to postulate functionally graded material...
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Highly-Miniaturized Self-Quadruplexing Antenna Based on Substrate-Integrated Rectangular Cavity
PublicationThis paper introduces a novel self-quadruplexing antenna (SQA) architecture using a substrate-integrated rectangular cavity (SIRC) for compact size, wide-frequency re-designability, and high isolation responses. The proposed SQA is developed by engraving two U-shaped slots (USSs) on the top conductor of the SIRC. The USSs are excited by employing four microstrip feedlines to achieve self-quadruplexing antenna characteristics. The...
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A palatal prosthesis from archaeological research in the St Francis of Assisi church in Cracow (Poland)
PublicationThe hard palate is a septum that not only prevents food from entering between the oral and nasal cavity, but also plays an important role during breathing or speech. The presence of cavities within it negatively affects the comfort of life of people with this type of impairment. Hence, in the literature one can find examples of the use of hard palate prostheses to restore the separation between the nasal and oral cavity. During...
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Microfluidically Frequency-Reconfigurable Self-Quadruplexing Antenna Based on Substrate Integrated Square-Cavity
PublicationIn this article, a novel concept of self-quadruplexing tunable antenna (SQTA) enabled by microfluidic channels is investigated. The operating channels are either filled with air or dielectric liquids to enable frequency tunability. The proposed SQTA is implemented on the substrate-integrated square-cavity (SISC). A swastika-shaped slot is milled on the top-surface of the SISC to create four quarter-mode resonators. The resonators...
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Flexible dye-sensitized solar cells based on Ti/TiO2 nanotubes photoanode and Pt-free and TCO-free counter electrode system
PublicationFlexible dye-sensitized solar cells (DSSCs) are getting more attention compared to standard glass covered DSSCs due to their unique commercial applications (e.g. tents or sail surfaces) and the possibility of rolling up into a small, portable device. In this work, titania nanotubes (TiO2 NT) modified with titania nanoparticles (TiO2 NP) were photoelectrochemically characterized as an anode for flexible dye-sensitized solar cells....
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Effective method for determining environmental loads on supporting structures for offshore wind turbines
PublicationThis paper presents a description of an effective method for determining loads due to waves and current acting on the supporting structures of the offshore wind turbines. This method is dedicated to the structures consisting of the cylindrical or conical elements as well as (truncates) pyramids of polygon with a large number of sides (8 or more). The presented computational method is based on the Morison equation, which was originally...
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Effective method for determining environmental loads on supporting structures for offshore wind turbines
PublicationThis paper presents a description of an effective method for determining loads due to waves, current and wind acting on the supporting structures of the offshore wind turbines. This method is dedicated to the structures consisting of the cylindrical or conical elements as well as (truncates) pyramids of polygon with a large number of sides (8 or more). The presented computational method is based on the Morison equation, which was...
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Fertility rebound and economic growth. New evidence for 18 countries over the period 1970-2011.
PublicationLong-run impact of economic growth on fertility trends is ambiguous and sensitive for in-time variations. Noticeably, over last decades, economic growth has led in many countries to significant falls in total fertility rates. However, recently, in high-income economies a kind of ‘fertility rebound’ emerged (Goldstein, 2009; Luci and Thevenon, 2011; Day, 2012), which supports the hypothesis that reversal trends in total fertility...
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Earthquake-induced pounding between asymmetric steel buildings
PublicationEarthquake-induced pounding between buildings has been the subject of numerous numerical and experimental studies in the resent years. The phe-nomenon may cause severe damage to structural elements as well as may also lead to the total collapse of colliding structures. A major reason leading to pounding between adjacent, insufficiently separated buildings results from the differences in their dynamic properties. The aim of this...
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Microwave-assisted synthesis of a TiO2-CuO heterojunction with enhanced photocatalytic activity against tetracycline
PublicationA microwave method was used for the synthesis of TiO2-CuO oxide systems. A detailed investigation was made of the effect of the molar ratio of components (TiO2:CuO=9:1, 7:3, 5:5, 3:7, 1:9) on the crystalline structure and morphology. Transmission electron microscopy (TEM) confirmed the presence of octahedral and rod-shaped titania particles and sheet copper(II) oxide particles; moreover, HRTEM analysis indicated the presence of...
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A Numerical Study on Baseline-Free Damage Detection Using Frequency Steerable Acoustic Transducers
PublicationIn structural health monitoring (SHM) a considerable amount of damage detection algorithms based on guided waves (GW) have been developed. Most of them rely on extensive transducer networks, besides preliminary reference measurements of the structures. This originated a growing demand for hardware simplification and cost reduction of the wave-based SHM methods, driving the conception of new solutions enabling both: the reduction...
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Design of a Patch Power Divider with Simple Structure and Ultra-Broadband Harmonics Suppression
PublicationThis paper introduces a simple H-shaped patch Wilkinson power divider (WPD), which provides ultra wide harmonics suppression band. The presented WPD designed at 1.8 GHz, and exhibits good performance at the operating bandwidth. In the proposed divider structure, two simple patch low-pass filters (LPFs) are employed at each branch, and three open ended stubs are added at each port. The proposed divider, implemented using the aforementioned...
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Investigation on Filaments for 3D Printing of Nasal Septum Cartilage Implant
PublicationSeptoplasty is a widely used method in treating deviated septum. Although it is successfully implemented, there are problems with excessive bleeding, septal perforation, or infections. The use of anatomically shaped implants could help overcome these problems. This paper focuses on assessing the possibility of the usage of a nasal septum cartilage implant 3D printed from various market-available filaments. Five different types...