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Correlation between Compressive Strength and Heat of Hydration of Cement Mortars with Siliceous Fly Ash
PublikacjaThis paper presents the results of calorimetric and strength tests of mortars with ordinary Portland cement and two substitution rates (10 and 20%) of cement by siliceous fly ash. The prepared samples were cured under isothermal conditions at four different temperatures: 23, 33, 43 and 53 °C. Heat of hydration was measured using an isothermal calorimeter dedicated to monitor the hydration process of cementitious composites such...
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The best porous asphalt pavement in Sweden so far
PublikacjaIn 2010 a double-layer porous asphalt concrete (DPAC) pavement was constructed in various versions on the E4 motorway through the Swedish city Huskvarna. As a result of a court decision the Swedish Transport Administration had to reduce noise emission by applying a low noise road surface that would reduce A-weighted noise levels by 5 dB, as an average. Earlier experience in Sweden indicated that it was possible to obtain a high...
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Evaluation of Asphalt Mixture Low-Temperature Performance in Bending Beam Creep Test
PublikacjaLow-temperature cracking is one of the most common road pavement distress types in Poland. While bitumen performance can be evaluated in detail using bending beam rheometer (BBR) or dynamic shear rheometer (DSR) tests, none of the normalized test methods gives a comprehensive representation of low-temperature performance of the asphalt mixtures. This article presents the Bending Beam Creep test performed at temperatures from −20...
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Acoustic lifecycle study of the double-layer porous asphalt on E4 in Huskvarna, Sweden
PublikacjaIn 2010 a double-layer porous asphalt concrete (DPAC) pavement was constructed on the E4 motorway through the Swedish city Huskvarna. Earlier experience in Sweden indicated that it was feasible to obtain a high initial noise reduction but due to the widespread use of studded tires in winter, clogging and ravelling created losses of around 2 dB per year, with an expected acoustical lifetime of only 3 years. However, the improved...
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Investigation on Mode I Fracture Behavior of Hybrid Fiber-Reinforced Geopolymer Composites
PublikacjaRecent reports in the literature have shown that fber-reinforced geopolymer composites (FRGC) made with monofbers exhibit a signifcant enhancement in fracture energy. However, many aspects of the fracture performance of hybrid fberreinforced geopolymer composites (HFRGC) remain largely unexploited, and these are predominant for the structures. For the frst time, the mode I fracture energy of HFRGC is investigated. The mode I behavior...
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Odpowiedzialny biznes- modna koncepcja czy odrodzenie wartości?
PublikacjaOpracowanie porządkuje wiedzę na temat koncepcji społecznej odpowiedzialności biznesu oraz jej specyfiki w kontekście małych i średnich przedsiębiorstw. Omówione zostały różnice pomiędzy zastosowaniem CSR w dużych organizacjach i w MŚP, ze szczególnym uwzględnieniem przedsiębiorstw polskich. Predyspozycje do zaangażowania społecznego przedsiębiorcy przedstawione zostały na kilku modelach teoretycznych, a konkretne przykłady dobrych...
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Analiza kosztów i czasu budowy domu jednorodzinnego w technologii drewna krzyżowo klejonego CLT
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Analiza przyczepności prętów żebrowanych w betonie metodą pull-out na próbkach centrycznych i mimośrodowych
PublikacjaArtykuł dotyczy analizy przyczepności żebrowanego stalowego pręta zbrojeniowego w betonie. Celem pracy była ocena wpływu położenia pręta w betonowym bloku na lokalną zależność naprężenie przyczepności-poślizg. Podjęto także próbę numerycznej symulacji przeprowadzonych eksperymentów w programie ABAQUS. Analizę doświadczalną przeprowadzono za pomocą testu pull-out na dwóch rodzajach próbek – centrycznych i mimośrodowych w dwóch wariantach,...
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The importance of the bottom layer in double-layer porous asphalt for noise reduction
PublikacjaDouble-layer porous asphalt concrete (DPAC) surfaces are generally considered to be the acoustically most effective low noise road surfaces ready for implementation. While DPAC used on highways in warm climates may have an average life of around 8 years, in Scandinavia with severe winter climate DPAC usually survive only about 3 years; partly due to wear of studded tyres. An ongoing project in Sweden, applying DPAC and single-layer...
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WYBRANE WŁAŚCIWOŚCI FIZYCZNO-CHEMICZNE MIKROSFER I MOŻLIWOŚĆ ICH WYKORZYSTANIA W KOMPOZYTACH CEMENTOWYCH : The selected physico-chemical properties of microspheres and possibility of their use in cement composites
PublikacjaMicrospheres are formed during the mineral transformation stage in coal combustion. Their content in fly ashes from the combustion of different types of coals varies over a rather wide range from 0.01 to 4.8 wt.%. The microspheres have three main elements, silicon, aluminum and iron, the oxides of which account for about 89.0 wt.% of the material. Mineralogical analysis using XRD shows that microspheres mainly contain mullite and...
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El empleo en el marco de la transformación digital: Gig Economy vs Open Collaboration ¿dos caras de una misma moneda?
PublikacjaTal y como plantea Pérez [43, 44], estamos viviendo los efectos de una revolución tecnológica ligada al desarrollo de las TICs. Los procesos de innovación, describe, se retroalimentan colectivamente, involucrando diferentes actores (productores, proveedores, distribuidores y consumidores) entrelazados en clústeres o redes dinámicas y complejas. Estos procesos colectivos ayudan a desarrollar e implementar tecnologías y magnifican...
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Reverberation divergence in VR applications
PublikacjaThe aim of this project was to investigate the correlation between virtual reality (VR) imagery and ambisonic sound. With the increasing popularity of VR applications, understanding how sound is perceived in virtual environments is crucial for enhancing the immersiveness of the experience. By examining the relationship between visual scenes and sound scenes, this research attempts to explore how the interaction between vision and...
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Instalacja oświetleniowa w zbiorniku wody "Stary Sobieski" - rozważania o spektakularnym zabytku techniki
PublikacjaArtykuł przedstawia efekty badań autora nad niezwykle okazałą, ponad stuletnią instalacją elektryczną, która zachowała się w zabytkowym obiekcie infrastruktury wodociągowej w niemal 100% oryginalnej formie (nie licząc częściowej dewastacji). Jest to rzadki przykład tego rodzaju zabytku, ponieważ obiekty tego typu i w tym wieku zwykle podlegały modernizacji na przestrzeni lat albo, po wyłączeniu z eksploatacji zostały całkowicie...
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Diagnostyka ultradźwiękowa mostowej belki prefabrykowanej typu T metodą młoteczkową
PublikacjaZastosowanie prefabrykacji w budowie obiektów mostowych pozwala optymalizować zużycie energii i materiałów i tym samym redukować koszty budowanego obiektu. Prefabrykowane belki sprężone mogą występować jako elementy kablobetonowe wykonywane bezpośrednio na placu budowy lub powstawać w zakładzie prefabrykacji jako elementy strunobetonowe. Elementy prefabrykowane wytwarzane w warunkach przemysłowych muszą spełniać wymagania wysokiej trwałości,...
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Fragility analysis of structural pounding between adjacent structures arranged in series with various alignment configurations under near‑field earthquakes
PublikacjaA major cause of local to total damages is related to structural pounding in a large number of past earthquakes. In general, these collisions take place as a result of differences in the dynamic characteristics of the colliding structures. To acquire a better perception of the behavior of structures, in this paper, three structures featuring different heights are modeled in series and with various configurations next to each other...
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Building damage due to structural pounding during earthquakes
PublikacjaEarthquake-induced pounding between adjacent buildings has been identified as one of the reasons for substantial damage or even total collapse of colliding structures. A major reason leading to interactions in buildings results from the differences in their dynamic parameters and also from insufficient distance between the structures. Although the research on structural pounding has been much advanced, the studies have mainly been...
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DYNAMIC ANALYSIS OF THE RAILWAY BRIDGES IN POLAND WITH REGARDS TO HIGH-SPEED TRAINS PASSAGE ADJUSTMENT
PublikacjaThe dynamic analysis of the railway bridge in Tczew was carried out in the article as an example of such bridges adaptation suitability to handle high-speed trains. Calculations of railway bridges are greatly complicated and labor-consuming. The bridge model and a rolling stock passage simulation were developed in the SOFISTIK software. Three types of elements were used for the correct mapping of the structure in the calculation...
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Potential Impact of Waterway Development on Cultural Landscape Values: The Case of the Lower Vistula
PublikacjaThe northern (“lower”) section of the Vistula is on the route of two international waterways—E70 and E40. However, the current condition of the riverbed prevents larger vessels from passing through. Plans for the waterway date back to the beginning of the 20th century. Following Poland’s ratification of the European Agreement on Main Inland Waterways of International Importance in 2017, the general concept has been transformed...
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FEM modelling of screw displacement pile interaction with subsoil
PublikacjaPredicting the-settlement characteristics of piles is an important element in the designing of pile foundations. The most reliable method in evaluating pile-soil interaction is the static load test, preferably performed with instrumentation for measuring shaft and pile base resistances. This, however, is a mostly post-implementation test. In the design phase, prediction methods are needed, in which numerical simulations play an...
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Tyre/road noise reduction by a poroelastic road surface
PublikacjaLow noise road surfaces of existing types may in favourable cases and in new conditions provide up to 7 dB of noise reduction. For higher noise reductions, innovative solutions must be sought. Poroelastic road surfaces (PERS) may be such a solution, which currently is studied in the EU project PERSUADE. This paper presents results of trials with a PERS version prefabricated by one of the project partners. Tests were made in a laboratory...
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The geodetic monitoring of the engineering structure – a practical solution of the problem in 3D space
PublikacjaThe study raises the issues concerning the automatic system designed for the monitoring of movement of controlled points, located on the roof covering of the Forest Opera in Sopot. It presents the calculation algorithm proposed by authors. It takes into account the specific design and location of the test object. High forest stand makes it difficult to use distant reference points. Hence the reference points used to study the stability...
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The long-term properties of mineral-cement-emulsion mixtures
PublikacjaThis publication presents evaluation of long-term behavior of mineral-cement-emulsion (MCE) mixtures. MCE mixtures are among the major products of cold recycling of old asphalt pavements. They are composed by binding of the old materials reclaimed from the pavement and new mineral aggregate using two different binding agents – cement and bituminous emulsion. While bituminous emulsion dissolutes and binds materials quite fast, it...
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Temperature influence on tyre/road noise on poroelastic road surface based on laboratory measurements
PublikacjaThe temperature effect on measured tyre/road noise is very important phenomena as it may lead to significant errors in measurement results due to substantial influence of this parameter on the obtained values. It depends mainly on the particular tyre-road combination. It is different for dense and porous as well as for bituminous and cement concrete pavements. It differs also depending on tested tyre. The correction procedure for...
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Sustainable utilization of copper post-flotation waste in cement composites
PublikacjaThe current way of managing the copper ore flotation waste is by placing it in waste neutralization facilities. However, flotation waste has great potential in application in cement composites. The article presents the detailed characteristics of post-flotation waste (PFW) and three types of cements: CEM I, CEM II/B-V, and CEM III/A, 42.5 MPa class. The post-flotation waste added for 20% of the cement mass increase the water demand...
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Linear viscoelastic transversely isotropic model based on the spectral decomposition of elasticity tensors
PublikacjaThe linear viscoelasticity is still a useful model in the engineering for studying the behavior of materials loaded with different loading rates (frequencies). Certain types of materials reveal also an anisotropic behavior: fiber reinforced composites, asphalt concrete mixtures, or wood, to name a few. In general, researchers try to identify experimentally the dependence of engineering constants like: directional Young’s moduli...
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WERYFIKACJA KONCEPCJI PRZEGUBÓW PLASTYCZNYCH PROJEKTOWANYCH NA ODZIAŁYWANIA SEJSMICZNE WIADUKTU V6 OBWODNICY ISTAMBUŁU
PublikacjaW pracy zawarto wyniki analiz betonowego wiaduktu V6 budowanego w ciągu obwodnicy Istambułu w Turcji realizowanego w ramach projektu Northern Marmara Highway. Przeprawę stanowią dwie niezależne nitki o skrzynkowym przekroju poprzecznym i szerokości 22,00 m. Schemat statyczny obiektu to belka dziewięcioprzęsłowa o długości całkowitej 446,86 m oparta na podporach słupowych o zmiennej sztywności (rys.1) i wysokościach zmieniających...
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AUDIO SIGNAL EQUALIZATION BASED ON IMPULSE RESPONSE OF A LISTENING ROOM AND MUSIC CONTENT REPRODUCED
PublikacjaA research study presents investigations of the influence of the room acoustics on the frequency characteristic of the audio signal playback. First, a concept of a novel spectral equalization method of the room acoustic conditions is introduced. On the basis of the room spectral response, a system for room acoustics compensation based on an equalizer designed is proposed. The system settings depend on music genre recognized automatically....
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Measurements of Thermal Conductivity of LWC Cement Composites Using Simplified Laboratory Scale Method
PublikacjaThe implementation of low-energy construction includes aspects related to technological and material research regarding thermal insulation. New solutions are sought, firstly, to reduce heat losses and, secondly, to improve the environment conditions in isolated rooms. The effective heat resistance of insulating materials is inversely proportional to temperature and humidity. Cement composites filled with lightweight artificial...
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Load introduction to composite columns revisited—Significance of force allocation and shear connection stiffness
PublikacjaThe AISC 360-16 Specification recommends that the design shear force between parts of a composite column in the load introduction area shall be calculated based on the force allocation at ultimate limit state. Applicability of this straightforward method to the load levels that usually arise in slender composite columns is questionable, as this capacity-based force allocation is only true when the axial force is equal to the plastic...
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Automated Reasoning Based User Interface
PublikacjaMotivation: The ability to directly trace how requirements are implemented in a software system is crucial in domains that require a high level of trust (e.g. medicine, law, crisis management). This paper describes an approach that allows a high level of traceability to be achieved with model-driven engineering supported by automated reasoning. The paper gives an introduction to the novel, automated user interface synthesis in...
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Probabilistic seismic assessment of RC box-girder highway bridges with unequal-height piers subjected to earthquake-induced pounding
PublikacjaThis paper uses the probabilistic seismic assessment to study the effects of pounding and irregularity on the seismic behavior of typical concrete box-girder bridges with four levels of altitudinal irregularity. To extend the results for all bridges in the same class, uncertainty related to the earthquake, structural geometries, and materials are considered. Pounding is likely to take place in two cases: the first one concerns...
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Akustyka sali koncertowej Szkoły Muzycznej w Gdyni - projekt i realizacja
PublikacjaOmówiono zakres współpracy architekta, akustyka i projektanta wnętrza na przykładzie sali koncertowej Szkoły Muzycznej w Gdyni. Wskazano różnice między projektem akustycznym sali i projektem wnętrza. Podano zasady akustycznego projektowanie sali widowiskowej oraz znaczenie rozproszenia dźwięku dla jakości akustycznej sali. Przedstawiono zasady indywidualnego konstruowania ustrojów rozpraszających dźwięk oraz dostępne na rynku ustroje...
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Influence of Bitumen Type and Asphalt Mixture Composition on Low-Temperature Strength Properties According to Various Test Methods
PublikacjaIn regions with low-temperatures, action transverse cracks can appear in asphalt pavements as a result of thermal stresses that exceed the fracture strength of materials used in asphalt layers. To better understand thermal cracking phenomenon, strength properties of different asphalt mixtures were investigated. Four test methods were used to assess the influence of bitumen type and mixture composition on tensile strength properties...
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Results of acoustic emission tests of corrosion protection degree of ship steel tanks covered by means of protective coatings (Phase I)
PublikacjaThis paper presents methods and results of the 1st series of tests of acoustic emission (AE) signals, aimed at assessing degree of corrosion protection of a tank made of hull structural steel, protected by means of a protective coating combined from polyurethane layer and concrete filler. The tests were carried outin compliance with a method specially elaborated for application to the work in question. In the method were used requirements...
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Impact performance of novel multi-layered prepacked aggregate fibrous composites under compression and bending
PublikacjaMulti-layered Prepacked aggregate fibrous composite (MLPAFC) is a new type of concrete, which is prepared in two subsequent stages of aggregate-fibre skeleton prepacking and cementitious grouting. In this study, ten MLPAFC mixtures were prepared in three subsequent layers incorporating different contents of four different types of steel fibres. Long and short hooked-end and crimped steel fibers were adopted with 3.0 and 1.5% dosages...
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Dietary behaviour and physical activity policies in Europe: learnings from the Policy Evaluation Network (PEN)
PublikacjaThe European Policy Evaluation Network (PEN), initiated in autumn 2018, aimed at advancing the evidence base for public policies impacting dietary behaviour, physical activity and sedentary behaviours in Europe. This is needed because non-communicable diseases—the leading cause of global mortality—are substantially caused by physical inactivity and unhealthy dietary behaviours, which in turn are driven by upstream factors that...
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Pile Model Tests Using Strain Gauge Technology
PublikacjaOrdinary pile bearing capacity tests are usually carried out to determine the relationship between load and displacement of pile head. The measurement system required in such tests consists of force transducer and three or four displacement gauges. The whole system is installed at the pile head above the ground level. This approach, however, does not give us complete information about the pile-soil interaction. We can only determine...
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Seismic damage diagnosis in adjacent steel and RC MRFs considering pounding effects through improved wavelet-based damage-sensitive feature
PublikacjaThis paper aims to propose complex Morlet (cmorfb-fc) wavelet-based refined damage-sensitive feature (rDSF) as a new and more precise damage indicator to diagnose seismic damages in adjacent steel and Reinforced Concrete (RC) Moment Resisting Frames (MRFs) assuming pounding conditions using acceleration responses. The considered structures include 6- and 9-story steel and 4- and 8-story RC benchmark...
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The rigid and flexible road pavements in terms of life cycle costs
PublikacjaThe cost of road pavement construction, its durability and reliability depends on many factors, including: the scope and detail of the technical design, quality of work but also the scope of works related to its maintenance, conservation and operation. Determining the amount of rational expenses, in terms of the life cycle cost of the pavement, requires determination and consideration of the above issues, already at the planning...
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Damage-involved response of two colliding buildings under non-uniform earthquake loading
PublikacjaPounding between insufficiently separated buildings, which may result in considerable damage or may even lead to the total collapse of colliding structures, has been repeatedly observed during earthquakes. Earthquake-induced collisions of buildings has been intensively studied applying various structural models. It was assumed in the analyses, however, that the seismic excitation is identical for all structural supports; whereas,...
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The use of lightweight aggregate saturated with PCM as a temperature stabilizing material for road surfaces.
PublikacjaThis paper presents the possibility of adding lightweight building aggregates to increase the stability – mechanical as well as thermal - of constructions and road objects. This stability can be achieved through saturating the porous granules of aggregate with a phase-change material (PCM) that allows the accumulation of solar heat. Intense solar radiation, especially during the summer, can cause the asphalt on road surfaces, bridges...
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Analysis of a caustic formed by a spherical reflector: Impact of a caustic on architectural acoustics
PublikacjaFocusing sound in rooms intended for listening to music or speech is an acoustic defect. Design recommendations provide remedial steps to effectively prevent this. However, there is a category of objects of high historical or architectural value in which the sound focus correction is limited or even abandoned. This also applies to indoor or outdoor concert shells, installations for teaching and acoustic presentations, etc. The...
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Can Historic Interiors with Large Cubature be Turned Acoustically Correct?
PublikacjaHistoric interiors with large cubature, such as reception, theatrical, and concert halls, need to be renovated periodically if they are to be preserved as cultural heritage for future generations. In such cases it is necessary to maintain appropriate balance between requirements imposed by heritage conservation authorities office which are usually being given a higher priority, applicable safety regulations, and the comfort of...
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Modal analysis of a steel grandstand
PublikacjaAmong the issues related to the idea of sustainable society is the safety of civil engineering structures devoted to satisfy different needs of people. One of the types of structures devoted to satisfy recreational needs are grandstands, which are used during sport events or music concerts. It is obligatory to consider interaction between structure and crowd load especially when the crowd movement involves rhythmic jumping, dancing,...
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Eksperymentalne i numeryczne badania parametrów dynamicznych trybuny stalowej
PublikacjaTrybuny stalowe to konstrukcje, które odnajdują swoje zastosowanie głównie podczas wydarzeń sportowych, koncertów muzycznych oraz innych wydarzeń, którym towarzyszą rytmiczne aktywności widzów i głośna muzyka. Ze względu na smukłość oraz lekkość elementów z jakich wykonana jest konstrukcja trybuny jest ona bardzo łatwo wzbudzana przez ludzi do drgań. Z przeprowadzonej w pracy [4] analizy modalnej wynika, że masa ludzi prowadzi...
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On the Structure of Time in Computational Semantics of a Variable-Step Solver for Hybrid Behavior Analysis
PublikacjaHybrid dynamic systems combine continuous and discrete behavior. Often, computational approaches are employed to derive behaviors that approximate the analytic solution. An important part of this is the approximation of differential equation behavior by numerical integration. The accuracy and computational efficiency of the integration usually depend on the complexity of the method and its implicated approximation errors, especially...
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Composite as a Material of the Future in the Era of Green Deal Implementation Strategies
PublikacjaComposite materials have become synonymous with modernity, desired in nearly every aspect of our daily lives, from simple everyday objects to sanitary facilities, pipelines, the construction of modern sewer networks, their renovation, water supply, and storage reservoirs, to complex structures—automotive, planes, and space science. Composites have seen a considerable rise in attention owing to their characteristics, durability,...
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Nonlocal Models of Plates and Shells with Applications in Micro- and Nanomechanics
PublikacjaNowadays, the use of small-scale structures in micro/nanomachines has become more and more widespread. The most important applications of such small-sized parts are in micro-electro-mechanical systems (MEMS) as well as nano-electro-mechanical systems (NEMS) as actuators, sensors, energy harvesters. For example, nanosensors are nanoscale devices that measure physical quantities and convert these to signals that can be detected and...
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Generating actionable evidence from free-text feedback to improve maternity and acute hospital experiences: A computational text analytics & predictive modelling approach
PublikacjaBackground Patient experience surveys are a key source of evidence for supporting decision-making and quality improvement in healthcare services. These surveys contain two main types of questions: closed and open-ended, asking about patients’ care experiences. Apart from the knowledge obtained from analysing closed-ended questions, invaluable insights can be gleaned from free-text data. Advanced analytics techniques are increasingly...
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Experimental study on earthquake-induced pounding between steel structures
PublikacjaPounding between adjacent structures has been repeatedly observed during major earthquakes. The phenomenon may cause some local damage at the points of interactions, it may also lead to substantial destruction, permanent deformations or total collapse of colliding structures. The effects of earthquake-induced structural pounding have been studied for more than three decades now. However, most of the studies concerned masonry as...