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The Proposition of an Automated Honing Cell with Advanced Monitoring
PublicationHoning of holes allows for small shape deviation and a low value of a roughness profile parameter, e.g., Ra parameter. The honing process heats the workpiece and raises its temperature. The increase in temperature causes thermal deformations of the honed holes. The article proposes the construction of a honing cell, containing in addition to CNC honing machine: thermographic camera, sound intensity meter, and software for collecting...
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Defining a novel domain that provides an essential contribution to site-specific interaction of Rep protein with DNA
PublicationAn essential feature of replication initiation proteins is their ability to bind to DNA. In this work, we describe a new domain that contributes to a replication initiator sequence-specific interaction with DNA. Applying biochemical assays and structure prediction methods coupled with DNA–protein crosslinking, mass spectrometry, and construction and analysis of mutant proteins, we identified that the replication initiator of the...
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Experimental Research of an Axial Piston Pump with Displaced Swash Plate Axis of Rotation
PublicationThe article describes the influence of displacement of the swash plate rotation axis on the efficiency of axial piston pumps. The dead space volume was defined as the volume of the working chamber in the extreme position of the piston at the end of the pumping phase and its variability was determined as a function of the position of the axis of rotation of the swash plate and the swing angle of swash plate. The influence of swash...
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Hyperbolic Asynchronous Method of a Radio Navigation Technique
PublicationHumans have always wanted to determine position in an unknown environment. At the beginning methods were simple. They were based on the observation of characteristic points, in the case of shipping additional observations of the coastline. Then came navigation based on astronomical methods (astronavigation). At the beginning of the XX-century a new way of determining the current location was developed. It has used radiowave signals....
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Two-Stage Variable-Fidelity Modeling of Antennas with Domain Confinement
PublicationSurrogate modeling has become the method of choice in solving an increasing number of antenna design tasks, especially those involving expensive full-wave electromagnetic (EM) simulations. Notwithstanding, the curse of dimensionality considerably affects conventional metamodeling methods, and their capability to efficiently handle nonlinear antenna characteristics over broad ranges of the system parameters is limited. Performance-driven...
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Influence of effective width of flange on calculation and reinforcement dimensioning of beam of reinforced concrete frame
PublicationThe paper analyses the influence of modelling the cross-section of a beam in two-storey reinforced concrete frame of industrial warehouse with dimensions: 18.0 m × 32.0 m using bar elements on the results of bending moments, the value of elastic deflection and the dimensioning of reinforcement due to bending. Six options were considered: a beam as a rectangular section and five T-beam variants with different definitions of effective...
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Thermal properties of a cement composite containing phase change materials (PCMs) with post-pyrolytic char obtained from spent tyres as a carrier
PublicationThis work examines the possible use of post-pyrolysis char made from spent vehicle tyres as a carrier for phase change materials (PCM), which could be used as an additive to cement mortar. Because of the ability of PCM to accumulate heat, the cement composite obtained from it, apart from its structural and strength properties, will acquire an additional energy storage function, which can be very important for energy-saving construction. In...
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Time travel without paradoxes: Ring resonator as a universal paradigm for looped quantum evolutions
PublicationA ring resonator involves a scattering process where a part of the output is fed again into the input. The same formal structure is encountered in the problem of time travel in a neighborhood of a closed timelike curve (CTC). We know how to describe quantum optics of ring resonators, and the resulting description agrees with experiment. We can apply the same formal strategy to any looped quantum evolution, in particular to the...
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Further development of the poroelastic road surface within the new Polish project SEPOR
PublicationRoad surfaces have a direct impact on noise generated by rolling tyres, the main and dominant source of noise of moving vehicles. Road surface texture, porosity and stiffness/elasticity govern the pavement contribution to tyre/road noise the most. An experimental PoroElastic Road Surface (PERS) is a wearing course with a high content of interconnected voids (pores) and with an elastic behavior due to the use of small particles...
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COMPARATIVE ANALYSIS OF POINT CLOUDS OBTAINED BY TLS AND PHOTOGRAMMETRY
PublicationTechnical progress in the field of 3D modelling resulted in increasing use of such technics to create a virtual 3D models of objects. Three-dimensional spatial models are used in a wide range of applications such as inventorisation of architectural-construction, an inventorisation of archaeological sites, medicine and wide-known engineering. Spatial models are created based on the point clouds acquired with laser scanners or photogrammetry....
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Influence of service ageing on polyester-reinforced polyvinyl chloride-coated fabrics reported through mathematical material models
PublicationIn this paper the coupled service (constructional tension) and environmental (sunlight, rainfalls, temperature variations) ageing influence on the polyester-reinforced polyvinyl chloride (PVC)-coated fabric VALMEX is studied. Two cases of the same fabric have been analyzed: one USED for 20 years on the real construction of the Forest Opera in Sopot (Poland), and one kept as a spare material (NOT USED). The following tests have...
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NUMERICAL MODEL OF PLASTIC DESTRUCTION OF THICK STEEL STRUCTURAL ELEMENTS
PublicationIn the shipbuilding industry, the risk of brittle fracture of the structure is limited by using certified materials with specified impact strength, determined by the Charpy method (for a given design temperature) and by supervising the welding processes (technology qualification, production supervision, non-destructive testing). For off-shore constructions, classical shipbuilding requirements may not be sufficient. Therefore, the...
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THE PROBLEM OF AIRFLOW AROUND BUILDINGS CLUSTERS IN DIFFERENT CONFIGURATIONS
PublicationIn the paper, the authors discuss the construction of a model of an exemplary urban layout. Numerical simulation has been performed by means of a commercial software Fluent using two different turbulence models: the popular k-ε realizable one, and the Reynolds Stress Model (RSM), which is still being developed. The former is a 2-equations model, while the latter – is a RSM model – that consists of 7 equations. The studies have...
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Trust, Tacit Knowledge Sharing, Project Performance and their Managerial Implications
PublicationTacit Knowledge Sharing is increasingly attracting the attention of scientists and managers intrigued by their potential application for creating innovative solutions. Project management as a set of methodologies and best practices need to be charged by knowledge. The research problem tackled in this article refers to a current managerial problem regarding tacit knowledge sharing execution in project based organizations. The objective...
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Tacit Knowledge Sharing and Creativity. How to Derive Innovation from Project Teams?
PublicationModern companies are increasingly likely to work in a project management environment, which ensures their success in the implementation of innovation. The aim of the study is to prove that tacit knowledge is a mediator for creativity and project performance. Creativity as one of the crucial sources of innovation is stimulated by tacit knowledge. Bearing this fact in mind, the authors studied relations between tacit knowledge, creativity...
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Extraction and evaluation of gas-flow-dependent features from dynamic measurements of gas sensors array
PublicationGas analyzers based on gas sensors are the devices which enable recognition of various kinds of volatile compounds. They have continuously been developed and investigated for over three decades, however there are still limitations which slow down the implementation of those devices in many applications. For example, the main drawbacks are the lack of selectivity, sensitivity...
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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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Modern GFRP Composite Footbridges
PublicationApplication of GFRP composites in civil engineering is still not large but already noticeable. Advantages of this material, such as: low volume weight, relatively high stiffness and strength, well fatigue resistance, easiness in shaping, high material damping and high environmental resistance, make it attractive for bridge and in particular foot-bridge designers. It is estimated that nowadays in the world there are realized hundreds...
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Wyznaczanie wytrzymałości betonu na podstawie funkcji dojrzałości wg amerykańskiej normy ASTM C1074-11
PublicationArtykuł poświęcono wyznaczaniu wytrzymałości betonu na podstawie funkcji dojrzałości wg normy ASTM C1074-11 (ang. Maturity Method). Metoda bazuje na rejestracji zmian tem - peratury w trakcie hydratacji dojrzewającego betonu. Wartykule zaprezentowano procedurę badawczą służącą wyznaczeniu funk - cji dojrzałości dla wybranej mieszanki betonowej oraz zależności wytrzymałość-dojrzałość. Celem badań jest wyznaczanie zmian w czasie...
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Skutki zwarć łukowych w średnionapięciowych rozdzielnicach okrętowych z izolacją powietrzną
PublicationW artykule scharakteryzowano moc i napięcie łuku, jak również przedstawiono model termodynamiczny służący do obliczania ciśnienia i temperatury gazów w otoczeniu łuku zwarciowego. Przedstawiono przykładowy układ elektrowni okrętowej i zasilania najważniejszych odbiorników na statku do przewozu kontenerów, w tym 600 kontenerów chłodzonych. Na podstawie parametrów prądnic i silników, odbiorników zasilanych z rozdzielnicy głównej...
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Gdyńskie chłodnie portowe - studium przypadku przemysłowej architektury portowej okresu modernizmu
PublicationArtykuł podejmuje tematykę obiektów monumentalnej architektury przemysłowej portu gdyńskiego, o funkcji chłodni. Rozwój technologii chłodzenia spowodował, że od połowy XIX w. obiekty takie budowano w dużych, zazwyczaj międzynarodowych ośrodkach dla zapewnienia wysokiego poziomu obsługi handlu produktami łatwo psującymi się. Dynamiczny rozwój portowego zaplecza Gdyni w okresie międzywojennym zaowocował powstaniem aż trzech budowli...
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Analiza czynników wpływających na prędkość pojazdów transportu zbiorowego na przykładzie Gdańska
PublicationW referacie przedstawiono istotę problemu szacowania prędkości pojazdów transportu zbiorowego w szczególności w zakresie modelowania ruchu. Przedstawiono i omówiono wyniki przeprowadzonych w maju ubiegłego roku pomiarów czasu przejazdu pojazdów transportu zbiorowego na obszarze Gdańska w ramach budowy systemu sterowania ruchem TRISTAR. Otrzymane wyniki zestawiono w celu zaprezentowania statystyki oraz zidentyfikowania czynników...
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Przepustowość przepustu niezatopionego
PublicationPodczas przepływu w warunkach niezatopionego wlotu i wylotu w przewodzie przepustu woda tworzyć będzie swobodne zwierciadło. Przepływ bezciśnieniowy w przewodzie przepustu może wystąpić również w warunkach zatopionego wlotu. W pracy porównano wyniki obliczeń przepustowości całego przepustu i samego przewodu o przekroju kołowym i kwadratowym. W warunkach spokojnego ruchu wody, przy braku spiętrzenia na wylocie, o przepustowości...
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Określenie parametrów modelowania geometrii krzyżownic rozjazdów zwyczajnych dla potrzeb budowy i utrzymania linii kolejowych
PublicationZdecydowana większość rozjazdów występująca na liniach kolejowych w Polsce to rozjazdy zwyczajne o typowym zestawie parametrów. Z tego powodu analiza przypadków nietypowych (takich jak rozjazdy o zmiennej krzywiźnie toru zwrotnego) może być utrudniona. Wirtualny model geometryczno-konstrukcyjny rozjazdu, generowany w oparciu o metody analityczne, stanowić może narzędzie użyteczne w sferze projektowania, konstrukcji oraz diagnostyki...
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Estakada E2 - kluczowy obiekt Obwodnicy Wałcza
PublicationW artykule przedstawiono uwarunkowania i przebieg projektowania estakady E2 z betonu sprężonego w ciągu Obwodnicy Wałcza. Pokazano efekt procesu optymalizacji projektu pierwotnego. Opisano przeprowadzone analizy wynikające z przyjętej technologii nasuwania podłużnego oraz istotne aspekty, które należy poruszyć przy wyborze tej technologii. Zaprezentowano modele numeryczne konstrukcji przęseł i metodę analizy z uwzględnieniem pracy...
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MOST PODWIESZONY kreowanie przestrzeni i konsekwencje konstrukcyjne
PublicationProjektowanie i budowa - wyzwania dla projektantów i wykonawców mostów. Mosty podwieszone i wiszące ich estetyka i konsekwencje strukturalne. Artykuł dotyczy aspektów estetycznych i konstrukcyjnych zaprojektowanych pylonów dla mostów podwieszonych lub wiszących. Autor zwraca uwagę na fakt, że niezwykłe rozwiązanie konstrukcyjne zastosowane do kładki lub małego wiaduktu może działać prawidłowo dzięki zjawiskom efektu skali. Nadzwyczajne...
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Korozja i zniszczenia kształtowników stalowych o przekrojach zamkniętych
PublicationW artykule przedstawiono spotykany na obiektach budowlanych problem rozwoju korozji na wewnętrznych powierzchniach kształtowników zamkniętych eksploatowanych w środowisku zewnętrznym. Zachodzące wewnętrzne procesy korozyjne oraz towarzyszące im siły niszczące w związku z zamarzającą wewnątrz profili wodą, powodują utratę nośności i obniżenie bezpieczeństwa eksploatacji, przez co przyczyniają się do powstawania stanów awaryjnych....
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Nondestructive Testing of the Miter Gates Using Various Measurement Methods
PublicationWhen any problems related to civil engineering structures appear, identifying the issue through the usage of only one measuring method is difficult. Therefore, comprehensive tests are required to identify the main source. The strains and displacement measurements, as well as modal identification, are widely used in the nondestructive testing of structures. However, measurements are usually carried out at several points and confirm...
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Study on the Coastline Evolution in Sopot (2008–2018) Based on Landsat Satellite Imagery
PublicationThe coastline is the boundary between the water surface in a reservoir or watercourse and the land, which is characterised by high instability and functional diversity. For these reasons, research on coastal monitoring has been conducted for several decades. Currently, satellite images performed with synthetic aperture radars (SARs) are used to determine its course and variability together with high-resolution multispectral imagery...
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An MTA-phosphorylase gene discovered in the metagenomic library derived from Antarctic top soil during screening for lipolytic active clones confers strong pink fluorescence in the presence of rhodamine B.
PublicationIn this work, we present the construction of a metagenomic library in Escherichiacoli using the pUC19 vector and environmental DNA directly isolated fromAntarctic topsoil and screened for lipolytic enzymes. Unexpectedly, the screeningon agar supplemented with olive oil and rhodamine B revealed one unusual pinkfluorescent clone (PINKuv) out of 85 000 clones. This clone harbored a plasmid,pPINKuv, which has an insert of 8317 bp that...
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Identification and molecular modeling of a novel lipase from an Antarctic soil metagenomic library.
PublicationIn this work, we present the construction of a metagenomic library in Escherichia coli using pUC19 vector and environmental DNA directly isolated from Antarctic topsoil and screened for lipolytic enzymes. The screening on agar supplemented with olive oil and rhodamine B revealed one clone with lipolytic activity (Lip1) out of 11,000 E. coli clones. This clone harbored a plasmid, pLip1, which has an insert of 4722 bp that has been...
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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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PERS - QUIET ROAD SURFACE FOR URBAN AREAS
PublicationTraffic noise is one of the most important environmental problems in densely populated urban areas. At low speeds the tyre/road interaction dominates all other sources. It is anticipated that when electric and hybrid vehicles gain dominance in city traffic, the importance of tyre/road noise will still increase as electric engines are much less noisy than combustion engines. On the other hand, electric and hybrid urban vehicles...
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Chiral Schiff base complexes as an effective catalyst in Diels-Alder reaction
PublicationDiels Alder reaction is a very important tool in carbon-carbon bond formation. It is a cycloaddition between a conjugated diene and a second compound called dienophile. Where one or more heteroatoms are present in the diene and/or dienophile framework, the cycloaddition is called hetero-Diels-Alder reaction (HDA). The asymmetric Diels-Alder reaction is among the most powerful available methodologies for that construction of optically...
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Comparative Analysis of Developed Rainfall Intensity–Duration–Frequency Curves for Erbil with Other Iraqi Urban Areas
PublicationRainfall Intensity–Duration–Frequency (IDF) relationships are widely used in water infrastructure design and construction. IDF curves represent the relationship between rainfall intensity, duration, and frequency, and are obtained by analyzing observed data. These relationships are critical for the safe design of flood protection structures, storm sewers, culverts, bridges, etc. In this study, the IDF curves and empirical IDF formulas...
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A multi‐industry and cross‐country comparison of technology contribution to formal and informal knowledge sharing processes for innovativeness
PublicationThe study explores the impact of organizational information technology (IT) competency on knowledge sharing, both explicit and tacit, in the context of innovativeness of products and processes. Knowledge sharing is then assessed in terms of tacit-to-explicit conversion and the impact of both types of knowledge on organizational innovation. Both process (internal) and product/service (external) innovation are included. As an extension,...
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Fast EM-Driven Nature-Inspired Optimization of Antenna Input Characteristics Using Response Features and Variable-Resolution Simulation Models
PublicationUtilization of optimization technique is a must in the design of contemporary antenna systems. Often, global search methods are necessary, which are associated with high computational costs when conducted at the level of full-wave electromagnetic (EM) models. In this study, we introduce an innovative method for globally optimizing reflection responses of multi-band antennas. Our approach uses surrogates constructed based on response...
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Determining an Architectural Character for Durban Residential Streetscapes
PublicationIn the current global context and in consideration of the Sustainable Development Goals, there is a strong need for urban densification. However, this development is also driven by processes linked to the idea of capitalism and 'economic growth'. Such development often leads to the loss of the 'genius loci' of a place and sometimes even overlooks the fact that the quality of the built environment greatly influences the health and...
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Damage of a post-tensioned concrete bridge – Unwanted cracks of the girders
PublicationThe cracking of a post-tensioned T-beam superstructure, which was built using the incremental launching method, is analyzed in the paper. The problem is studied in detail, as specific damage was observed in the form of longitudinal cracks, especially in the mid-height zone of the girder at the interface of two assembly sections. The paper is a case study. A detailed inspection is done and non-destructive testing results of the...
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Multi-Taper-Based Automatic Correction of Non-Anechoic Antenna Measurements
PublicationPrototype measurements belong to the key steps in the development of antenna structures. Although accurate validation of their far-field performance can be realized in dedicated facilities, such as anechoic chambers, the high cost of their construction and maintenance might not be justified if the main goal of measurements is to support teaching or low-budget research. Instead, they can be performed in non-anechoic conditions and...
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Improving medical experts’ efficiency of misinformation detection: an exploratory study
PublicationFighting medical disinformation in the era of the pandemic is an increasingly important problem. Today, automatic systems for assessing the credibility of medical information do not offer sufficient precision, so human supervision and the involvement of medical expert annotators are required. Our work aims to optimize the utilization of medical experts’ time. We also equip them with tools for semi-automatic initial verification...
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Entrained Flow Plasma Gasification of Sewage Sludge–Proof-of-Concept and Fate of Inorganics
PublicationSewage sludge is a residue of wastewater processing that is biologically active and consists of water, organic matter, including dead and living pathogens, polycyclic aromatic hydrocarbons, and heavy metals, as well as organic and inorganic pollutants. Landfilling is on the decline, giving way to more environmentally friendly utilisation routes. This paper presents the results of a two-stage gasification–vitrification system, using...
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Quality assessment of low voltage surge arresters
PublicationUsers expect reliable operation of the surge arrester during overvoltages, which may originate from a switching process or a lightning discharge. The necessary conditions to guarantee these expectations are: appropriate construction of the surge arrester, its production being maintained in accordance with technical standards, and a positive results of the type test (as well routine and acceptance tests). The recipient, especially...
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Chemical, Physical, and Mechanical Properties of 95-Year-Old Concrete Built-In Arch Bridge
PublicationThis research aimed to determine the durability and strength of an old concrete built-in arch bridge based on selected mechanical, physical, and chemical properties of the concrete. The bridge was erected in 1925 and is located in Jagodnik (northern Poland). Cylindrical specimens were taken from the side ribs connected to the top plate using a concrete core borehole diamond drill machine. The properties of the old concrete were...
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Improving the Quality of Magnetic Signature Reproduction by Increasing Flexibility of Multi-Dipole Model Structure and Enriching Measurement Information
PublicationThe paper presents the construction of a multi-dipole model that allows reproducing magneticsignatures of ferromagnetic objects. The virtual object used in the paper is an ellipsoid, which is the sourceof synthetic data. To make the situation more realistic, noise is added to the synthetic data. Two significantimprovements compared to previous work are presented. Three-axial magnetometers are introduced insteadof uniaxial magnetometers....
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Low noise poroelastic road pavements based on modified asphalt binder
PublicationTire/road noise is one of the most important environmental problems related to road traffic. As the most effective way to fight noise is reduction of sound emission from the source, a lot of work is being done to improve tire and road surfaces construction. This paper describes the first “road” results obtained within the SEPOR project, which is focused on developing a low noise poroelastic road surface based on bituminous binder....
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Analysis of the Dynamic Height Distribution at the Estuary of the Odra River Based on Gravimetric Measurements Acquired with the Use of a Light Survey Boat—A Case Study
PublicationLaCoste) for determining the dynamic height along the Odra River, in northwest Poland. The gravity measurement campaign described in this article was conducted on a small, hybrid-powered survey vessel (overall length: 9.5 m). We discuss a method for processing the results of gravimetric measurements performed on a mobile platform affected by strong external disturbances. Because measurement noise in most cases consists of signals...
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Clays as Inhibitors of Polyurethane Foams’ Flammability
PublicationPolyurethanes are a very important group of polymers with an extensive range of applications in different branches of industry. In the form of foams, they are mainly used in bedding, furniture, building, construction, and automotive sectors. Due to human safety reasons, these applications require an appropriate level of flame retardance, often required by various law regulations. Nevertheless, without the proper modifications,...
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Numerical analysis of high temperature minichannel heat exchanger for recuperative microturbine system
PublicationConsidering the development of energy sector, distributed small-scale power generation, e.g., gas micro-CHP, is attracting considerable interest. In such installations, the heat exchanger is one of the key components possessing a significant influence on overall performance. Most studies concentrate on units operating below 900C, which do not fulfil the requirements of gas micro-CHP. Therefore, there remains a challenge to design...
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Aeration Process in Bioreactors as the Main Energy Consumer in a Wastewater Treatment Plant. Review of Solutions and Methods of Process Optimization
PublicationDue to the key role of the biological decomposition process of organic compounds in wastewater treatment, a very important thing is appropriate aeration of activated sludge, because microorganisms have to be supplied with an appropriate amount of oxygen. Aeration is one of the most energy-consuming processes in the conventional activated sludge systems of wastewater treatment technology (may consume from 50% to 90% of electricity...