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Search results for: Cable-stayed bridges
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Podstawy określania współczynników równoważności obciążenia osi do projektowania nawierzchni drogowych
PublicationPraca przedstawia rys historyczny rozwoju charakterystyki obciążenia dróg przez ruch. Omówiono wpływ przyjęcia wielkości obciążenia standardowego osi równoważnej na wyniki analizy ruchu. Przedstawiono metodę doświadczalną AASHTO i współczynniki obliczone według tej metody w przypadku polskich warunków. Podano wzory do obliczeń współczynników dla osi podwójnych i potrójnych. Przedstawiono metodę francuską i jej porównanie z metodą...
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Kształtowanie nowych japońskich ''mostów wstęgowych''
PublicationNa przykładzie kilku ostatnio wybudowanych w Japonii ''mostów wstęgowych'', omówiono samą ideę, jej przeobrażenia oraz aktualne tendencje rozwojowe tego typu konstrukcji. Dowiązano do pewnych podobnych konstrukcji europejskich budowanych w przeszłości.
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Wpływ różnych cięgien na właściwości statyczne i dynamiczne kładki podwieszonej
PublicationPrzedstawiono analizę wpływu rodzaju cięgna na cechy statyczne i dynamiczne konstrukcji podwieszonej kładki dla pieszych. Rozważano pręty lite, liny zwite i sploty 7*č5.
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ANALIZA WYBRANYCH CECH MECHANICZNYCH MIESZANEK MINERALNO-CEMENTOWO-EMULSYJNYCH (MCE)
PublicationW ostatnich latach mieszanki mineralno-cementowo-emulsyjne (MCE) stają się materia³em coraz częściej wykorzystywanym przy projektowaniu remontów i przebudów nawierzchni z wykorzystaniem recyklingu. Materiał ten zyskuje coraz większą popularność, ponieważ pozwala w sposób racjonalny i bez uszczerbku dla środowiska naturalnego ponownie wykorzystać materiały pochodzące z rozbiórki starych nawierzchni bitumicznych, w tym również materiały...
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Symulacja hałasu pojazdów w trakcie manewrowania z małymi prędkościami - model CP2009
PublicationOgraniczenie halasu związanego z ruchem drogowym możliwe jest jedynie poprzez skoordynowane dzialanie w zakresie doskonalenia pojazdów, opon nawierzchni drogowych i organizacji ruchu drogowego. Praca porusza zagadnienia związane z manewrowaniem pojazdów na parkingach, stacjach paliw, terminalach promowych itp. Omówiono metodę prognozowania poziomu mocy akustycznej emitowanej z obiektu typu parking z uwzględnieniem charakterystyk...
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Badania terenowe przemieszczeniowych pali i kolumn wkręcanych typu SDP i SDC
PublicationPrzedstawiono opis badań pali i kolumn wkręcanych typu SDP i SDC na terenowym poletku doświadczalnym, wykonanych w ramach projektu badawczego MNiSW. Badania statyczne pali i kolumn wykonano z pomiarem rozdziału siły w trzonach i w powiązaniu z badaniami CPT podłoża gruntowego. Określono wartości oporów jednostkowych gruntów niespoistych wzdłuż pobocznicy i pod podstawą pali wkręcanych oraz przedstawiono je w relacji do oporów gruntu...
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Budowa i kalibracja modeli spękań zmęczeniowych warstw asfaltowych nawierzchni drogowych w mechanistyczno-empirycznej metodzie AASHTO 2004
PublicationW artykule przedstawiono sposób tworzenia modeli spękań zmęczeniowych warstw asfaltowych w nowej amerykańskiej mechanistyczno-empirycznej metodzie projektowania nawierzchni AASHTO 2004. Opisano modele przyjęte do kalibracji, problem różnego zachowania się warstw asfaltowych naprężeniowo i odkształceniowo,przyjęte miary spękań zmęczeniowych. Przedstawiono także kalibrację opartą o badania na odcinkach doświadczalnych LTPP, symulację...
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Właściwości betonu impregnowanego kompozycjami epoksydowymi
PublicationZabezpieczając powierzchnię betonu przez impregnację w obiektach drogowych i mostowych, można w znacznym stopniu ograniczyć proces przenikania gazów i cieczy, a tym samym zapobiegać destrukcji. Przedmiotem opracowania jest wpływ własności materiałów impregnacyjnych na właściwości i trwałość betonu. Szczególną uwagę w przeprowadzonych badaniach skierowano na skład kompozycji żywicznych. Sporządzono 160 impregnatów, spośród których...
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Load capacity and serviceability conditions for footbridges made of fibre-reinforced polymer laminates = Warunki nośności i użytkowalności w odniesieniu do kładek z laminatów polimerowych
PublicationThe contribution is focused on derivation of the Ultimate Limit State (ULS) and Serviceability Limit State (SLS) design criteria for footbridges built of fibre-reinforced polymer matrix (FRP) laminates. The ULS design criterion is based on the design guidelines for above-ground, pressure, FRP composite tanks and the Tsai-Wu failure criterion, which is used to predict the onset of FRP laminates damage. The SLS criterion is based...
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ANALYSIS OF CLIMATIC ZONES IN POLAND WITH REGARD TO ASPHALT PERFORMANCE GRADING
PublicationTowards the end of the last century a new system of bitumen grading was developed and implemented as part of the American Strategic Highway Research Program (SHRP). Its aim was to better adjust the testing methods and requirements for road bitumens to the actual conditions in which those bitumens serve in road pavements. Currently in Poland, similarly as in the other EU countries, road bitumens are tested and classified with regard...
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Analiza trwałości zmęczeniowej asfaltów drogowych i modyfikowanych z wykorzystaniem testu liniowego zwiększania amplitudy / Analysis of the fatigue life of neat and modified bitumens using linear amplitude sweep test
PublicationThe paper presents an evaluation of the fatigue resistance of selected Polish bituminous binders: neat bitumen 50/70, polymer modified bitumen PMB 45/80-55 and polymer highly modified bitumen PMB 45/80-80. The linear amplitude sweep (LAS) test, which is a new bitumen performance grading test developed in the USA, and was used to assess the fatigue life of the bitumens. Highly modified bitumen 45/80-80 showed 10-20 times higher...
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Impact of reclaimed asphalt pavement (RAP) on low-temperature properties of asphalt concrete
PublicationHot mix recycling is a practice which enables reusing materials from old asphalt pavements. Current Polish regulations allow usage of RAP only for binder and base courses, and its amount is limited. Asphalt mixtures with RAP material have to fulfil requirements stated for typical asphalt mixtures. The research presents low-temperature properties of twelve different asphalt concretes with RAP material, determined using three-point...
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Application and evaluation of M-EPDG for performance analysis of Polish typical flexible and rigid pavements
PublicationThe main goal of the paper is to implement and evaluate the M-EPDG and the software AASHTOware to analyse the performance of new flexible and rigid pavements designed according to the Polish catalogues, which are comparable with analogous catalogues used in other European countries. For this purpose the site-specific inputs for Poland were determined and described in the paper as well as compared to the default input data used...
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Rebuilding Bailey Bridge to Bridge With Bascule Span – A Case Study
PublicationThe structural analysis of a road foldable prefabricated steel Bailey- type bridge located over the Tuga River in Żelichowo, Poland is performed in this paper. Interesting and untypical bridge redevelopment performed made it possible to lift the middle foldable bridge span by approximately 4.0 m concerning the existing state. The paper begins with a survey of literature carried out on the investigations of foldable Bailey-type...
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Application of guided wave propagation in diagnostics of steel bridge components
PublicationEarly detection of potential defects and identification of their location are necessary to ensure safe, reliable and long-term use of engineering structures. Non-destructive diagnostic tests based on guided wave propagation are becoming more popular because of the possibility to inspect large areas during a single measurement with a small number of sensors. The aim of this study is the application of guided wave propagation in...
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CFD-based evaluation of current-carrying capacity of power cables installed in free air
PublicationEvaluation of current-carrying capacity of power cables and selection of cross-sectional area of their conductors are mainly performed in accordance with requirements of EN, IEC or IEEE standards. However, these standards do not provide all methods of cables installation and location which occur in practice. Thus, in some cases, performance of advanced modeling of various thermal phenomena, affecting power cables current-carrying...
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RESOURCE ALLOCATION IN DAB+ BROADCASTING SYSTEM
PublicationWith over two billion receivers operating worldwide, radio transmission is by far the most accessible medium. It has been a part of our lives since the 1920’s and has become one of the most trusted and friendly mass media. Today, its popularity is still strong, despite the outcome of many electronic media. In order to transform the radio into a viable medium of the 21st century, it will have to migrate from analogue to digital...
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Improving the Survivability of Carrier Networks to Large-Scale Disasters
PublicationThis chapter is dedicated to the description of methods aiming to improve the survivability of carrier networks to large-scale disasters. First, a disaster classification and associated risk analysis is described, and the disaster-aware submarine fibre-optic cable deployment is addressed aiming to minimize the expected costs in case of natural disasters. Then, the chapter addresses the improvement of the network connectivity resilience...
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Once in a season – the pragmatic function of fuck in “BoJack Horseman” TV Show
PublicationThis article investigates the use and pragmatic functions of the swear word fuck in the “BoJack Horseman” produced by Netflix and bridges the gap in the linguistic research on this particular TVshow. Incorporating corpus linguistics tools, the BoJack Horseman Corpus was compiled and thelemma fuck has been investigated and analysed from the multimodal perspective....
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Investigating Analytics Dashboards’ Support for the Value-based Healthcare Delivery Model
PublicationImproving the value of care is one of the essential aspects of Value-Based Healthcare (VBHC) model today. VBHC is a new HC delivery model which is centered on patient health outcomes and improvements. There is anecdotal evidence that the use of decision aid tools like dashboards can play a significant role in the successful implementation of VBHC models. However, there has been little or no systematic studies and reviews to establish...
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Bridging the Gap Between Legitimacy and Neutralisation Strategies in Sustainability Reporting
PublicationAmid global sustainability challenges, such as climate change, companies operating in different industries face increasing demands for accountability and transparency. To meet these demands, sustainability reporting (SR) has become a mainstream business practice in communicating companies’ positive and negative sustainability impacts. This short paper aims to increase our understanding of how companies may release negative information...
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Analiza następstw potencjalnej awarii wanty mostu podwieszonego w Bydgoszczy
PublicationMost Uniwersytecki został zamknięty po siedmiu latach od oddania do użytkowania. Powodem były widoczne gołym okiem objawy znacznego przeciążenia w obrębie zakotwień. Krytyczne elementy konstrukcji mostu zostały wzmocnione i przywrócono go do ruchu. W artykule przedstawiono nieliniowe analizy statyczne i dynamiczne wykonane na modelu MES, prezentujące cztery scenariusze przebiegu zachowania konstrukcji po utracie nośności mocowania...
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Analysis of electromagnetic disturbances in DC network of grid connected building-integrated photovoltaic system
PublicationThis paper focuses on conducted electromagnetic interference (EMI) emissions and propagation in the DC network of grid connected building integrated photovoltaic (PV) system. The investigated PV system, consists of ten solar panels, cabling and the grid-connected one phase inverter. The EMI simulation model of the real PV system has been developed with the aid of impedance analyzer measurements of solar panels and the DC network...
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Evaluation of fire hazard in electrical installations due to unfavorable ambient thermal conditions
PublicationEvaluation of fire hazard caused by electrical installations is a difficult and important topic, and it limits the possibility of loss of life or health of people, as well as the occurrence of significant property damage. In particular, this hazard was caused by power cables and especially photovoltaic (PV) installations. The authors proved that power cables directly exposed to strong solar radiation are likely to exceed maximum...
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Sustainable development requires risky decisions - problematic 300 ton overweight transport passing a bridge
PublicationOversize load passages over bridges are one of the research issues related to sustainable development that engineering and scientific teams around the world have to deal with . The article presents the scope of activities that enabled the passage of an oversized vehicle with a total weight of over 300 tons over a reinforced concrete slab. The bridge load capacity is 30 tons. In order to assess the capacity of the bridge, detailed...
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Deterioration of masonry structure investigated by a thermal camera with a qualitative assessment of thermal image processing
PublicationThermal imaging is contemporary remote sensing measurement technique, which provides an image of the temperature distribution in the measured object. The method is widely used, due to its mobility as well as the non-destructive character of the measurement. Infrared thermography is especially relevant in the inspection of insulation, what is more, it is a suitable device for detecting thermal bridges and structural changes, which...
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Reliability assessment of an OVH HV power line truss transmission tower subjected to seismic loading
PublicationThe study focuses on the reliability of a transmission tower OS24 ON150 + 10, an element of an OVH HV power line, under seismic loading. In order to describe the seismic force, the real-life recording of the horizontal component of the El Centro earthquake was adopted. The amplitude and the period of this excitation are assumed random, their variation is described by Weibull distribution. The possible space state of the phenomenon...
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Assessing vehicle restraint systems on horizontal curves
PublicationHorizontal curves, an element of road infrastructure, have a statistically high number of accidents. Considering that horizontal curves in the last ten years have had app. 10% of all road accidents representing app. 14% of all fatalities on Polish roads, the issue is serious and requires more research and proper road safety treatments. Data for 2007 - 2016 show that in the case of accidents on horizontal curves app. 45% of the...
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Subjective Quality Evaluation of Speech Signals Transmitted via BPL-PLC Wired System
PublicationThe broadband over power line – power line communication (BPL-PLC) cable is resistant to electricity stoppage and partial damage of phase conductors. It maintains continuity of transmission in case of an emergency. These features make it an ideal solution for delivering data, e.g. in an underground mine environment, especially clear and easily understandable voice messages. This paper describes a subjective quality evaluation of...
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Modeling of a Quasi-Resonant DC Link Inverter Dedicated to Common-Mode Voltage and Ground Current Reduction
PublicationIn this paper, the modeling methodology of the AC drive system with a Parallel Quasi-Resonant DC Link Inverter (PQRDCLI) is described. A presented modeling approach is an attractive tool used for the effective evaluation of a common-mode (CM) voltage and grounds current reduction methods. Designed models of inverter, induction machine (IM), and cable are simple, thus the methods for parameter extraction are not complicated. Verification...
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China and the Chinese in the modern world. An interdisciplinary study
PublicationThis monograph is a collection of chapters devoted to modern China on various approaches. There is no future without a past and a modern China is a country that skillfully combines the new with the old and the authors have attempted to present this phenomenon in this book. It brings to light issues such as a honorificativity in Chinese administrative and legal documents, a comparison of Chinese and...
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Investigation of stability and limit load of a truss overhead opened bridge
PublicationThe paper presents selected methods of determining stability and limit load of a truss top chord in opened bridges. These methods include linear buckling and non-linear static analysis based on the finite element method and algorithms based on design code procedures. The described methods were tested on an example of a steel footbridge situated in Straszyn. The results of stability analysis are compared. The results of geometrical...
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Preparation and Characterization of Nanomaterial Consisting of Silica Aerogel & Carbon Tested as an Electrode in Non-Aqueous Media Containing Lithium Salt.
PublicationSilica aerogel (SiO2ag) was combined with carbonaceous material in the pyrolysis process of hydrocarbons. The obtained nanocomposite SiO2ag/C was amorphous, partially preserving the porous structure of SiO2ag. The specific surface area changes from 445.6 m2/g for pure SiO2ag to 205.52 m2/g SiO2ag/C. The 29Si MAS-NMR shows a three-dimensional matrix with silicon atoms connected to other silicon atoms by four...
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Modeling Object Oriented Systems via Controlled English Verbalization of Description Logic
PublicationThe need for formal methods for Object Oriented (OO) systems resulted in methods like UML and Lepus3 that are de-facto graphical languages equipped with formal tools that are able to handle the design of OO systems. However, they lack precise semantics which might lead to problems, such as inconsistencies or redundancies. On the other hand, to our knowledge, there is no approach that allows one to understand and follow the requirements...
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Mono- and polynuclear Co(II) silanethiolates with aliphatic diamines
PublicationFour Co(II) complexes, [Co{SSi(OtBu)3}2(dmpda)] 1, [Co{SSi(OtBu)3}2(bda)2]n2 [Co{SSi(OtBu)3}2(pda)2]n3 and [Co{SSi(OtBu)3}2(hda)2]n4 [dmpda = 3-(dimethylamino)-1-propylamine; bda = 1.4-butanediamine; pda = 1.5-pentanediamine; had = 1.6-hexanediamine] have been synthesized and characterized using X-ray diffraction. Complex 1 is mononuclear and contains Co(II) coordinated by dmpda molecule in chelating mode, whereas compounds 3 and...
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Point cloud based surface analysis of prestressed concrete element in exceeded state of serviceability
PublicationBy definition, serviceability state is characterized by the fact that despite meeting the requirements associated with carrying capacity, the object is not suitable for use. Serviceability limit state refers to factors, such as durability, overall stability, fire resistance, cracking, excessive vibration. Perfect examples of exceeded serviceability state are the improper vibration of a skyscraper, which inhabitants may suffer from...
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A dynamic vehicle-bridge model based on the modal identification results of an existing EN57 train and bridge spans with non-ballasted tracks
PublicationThis paper addresses the methodology of the bridge-vehicle dynamic model definition based on the free response measurements of an existing train and existing bridge spans. In the case of the railway vehicle, the methodology uses the impulse excitations of a single car by means of the wedge method. In the case of the bridge spans, free responses are collected after the passages of trains. The global modal parameters (frequencies...
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The experience of movement in the built form and space: A framework for movement evaluation in architecture
Publication“Movement in architecture” is an organized system of various types of movements stimulated by specific architectural elements. This research was conducted through a qualitative-analytical method and empirical and bibliographical research methods with the aim to categorize different types of movements based on the explorer and observer relationships with the built space and form. So far, most of the related studies have focused...
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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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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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The experience of movement in the built form and space: A framework for movement evaluation in architecture
Publication“Movement in architecture” is an organized system of various types of movements stimulated by specific architectural elements. This research was conducted through a qualitative-analytical method and empirical and bibliographical research methods with the aim to categorize different types of movements based on the explorer and observer relationships with the built space and form. So far, most of the related studies have focused...
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Rospuda - czy wszędzie budować mosty?
PublicationStreszczenie - SummaryThe article presents the problem of planning transport system in the areas of high natural and landscape values. Bridges and roads crossing valuable areas undergo Environmental Impact Assessment (EIA) Procedure. This procedure in Poland is often treated only as formal requirement, not as an instrument helping to solve conflicts and to minimise negative environmental and landscape effects. The potential of...
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Collagen Type II—Chitosan Interactions as Dependent on Hydroxylation and Acetylation Inferred from Molecular Dynamics Simulations
PublicationChitosan–collagen blends have been widely applied in tissue engineering, joints diseases treatment, and many other biomedical fields. Understanding the affinity between chitosan and collagen type II is particularly relevant in the context of mechanical properties modulation, which is closely associated with designing biomaterials suitable for cartilage and synovial fluid regeneration. However, many structural features influence...
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Revitalized Mill Island in Bydgoszcz - the identity of the place created by the Brda River and its tributary named Młynowka
PublicationMill Island in Bydgoszcz, Poland is an example of downtown public space where a meander of the Młynówka creates the identity of the area.Before 2005, the only outstanding local feature was the fact that its south and west ends resembled the Venetian canals. The way the other parts of Mill Island were managed was inappropriate for a downtown.A comprehensive revitalization programme is returning Mill Island public space to residents,...
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Studying road restraint systems to develop new guidelines
PublicationThe paper will present a proposed approach to such work along with preliminary results of numerical studies for selected problems using road safety devices such as safety barriers on horizontal curves, the effect of kerbs on bridges or the location of obstacles within the barrier’s working width. The paper will discuss assumptions to a methodology of numerical models, calculations and automated processing of data to help with assessing...
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The influence of Be addition on the structure and thermal properties of alkali-silicate glasses
PublicationBe-Na-(Li)-Si oxide glasses containing up to 15 mol% of BeO were prepared. Their structure was characterized by X-ray powder diffraction and Raman as well as infrared spectroscopic techniques, while their chemical compositions were examined by Inductively Coupled Plasma Optical Emission Spectrometry. All materials were found to be amorphous and contain Al contaminations from minor dissolution of the alumina crucibles. The results...
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Oddziaływania taboru na mosty kolejowe przy zmiennych parametrach ruchu
PublicationW pracy poruszono zagadnienia związane z identyfikacją oraz modelowaniem układu dynamicznego most-pojazd ruchomy. Za element szczególnie istotny uznano czynnik obciążający. Opracowano i wdrożono metodykę identyfikacji cech dynamicznych rzeczywistego pojazdu szynowego. Eksperyment badawczy przeprowadzono dla jednostki trakcyjnej EN57, jednak nie ma żadnych ograniczeń w stosowaniu metody dla innego, konwencjonalnego taboru szynowego....
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Wpływ sposobu odwzorowania pojazdu szynowego na odpowiedź dynamiczną przęsła mostowego
PublicationW pracy przedstawiono rezultaty analiz numerycznych oraz badań eksploatacyjnych dwóch przęseł mostowych wymuszonych ruchomym pojazdem szynowym. Pojazd odwzorowano za pomocą czterech modeli uproszczonych: strumienia sił skupionych, strumienia mas skupionych oraz strumieni oscylatorów jedno- i dwumasowych. Analizy numeryczne wykonano przy wykorzystaniu MES. Potrzebne parametry dynamiczne wyznaczono na podstawie wyników identyfikacji...
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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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Voltage variations and their reduction in a rural low-voltage network with PV sources of energy
PublicationRenewable sources of energy (RES), especially photovoltaic (PV) micro-sources, are very popular in many countries. This way of clean power production is applied on a wide scale in Poland as well. The Polish legal regulations and tariffs specify that every prosumer in a low-voltage network may feed this network with a power not higher than the maximum declared consumed power. In power networks with RES, the voltage level changes...