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Towards a Smart Sustainable City Roadmap
PublicationThis workshop of the CAP4CITY (Erasmus+ Strengthening Governance Capacity for Smart Sustainable Cities) project is to promote and stimulate the discussion and networking in the area of Digital Government. Smart Sustainable Cities and related concepts of Digital, Intelligent and Smart Cities represent a progression of how cities around the world apply digital technology to serve their populations, pursue sustainable socio-economic...
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Radio Channel Measurements in 868 MHz Off-Body Communications in a Ferry Environment
PublicationIn this paper, a characterization of the 868 MHz off-body radio channel in BANs is presented. Measurements were carried out in a ferry environment using a specific set-up. A method for path loss using radio distance measurements (RDMs) was developed. It allows to automate the measurements process and make it independent from the variable speed of a moving person. Based on the observed path loss as a function of distance, the obtained...
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Ultra-Compact Self-Quadruplexing Microfluidically Frequency Reconfigurable Slot Antenna Using Half-Mode SIW
PublicationIn this brief, the design of an ultra-compact self-quadruplexing frequency reconfigurable antenna (SQFRA) utilizing a half-mode substrate-integrated waveguide (HMSIW) and microfluidic channels is discussed. Four HMSIW cavities fed by four microstrip lines and slots are used to construct a highly compact antenna. The microstrip feedings to the HMSIW cavities are applied in such a way that the proposed antenna exhibits self-quadruplexing...
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An Empirical Propagation Model for Corridors in Office Buildings
PublicationThis paper presents an empirical propagation path loss model for corridors in office buildings. The proposed model estimates changeable character of radio signal attenuation, based on a special approach as a combination of the simple free-space model with the author’s model. The measurement stand and measurement scenario are described. The propagation path loss research have been made in corridor for different frequencies in range...
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The Effect of Increasing the Amount of Indium Alloying Material on the Efficiency of Sacrificial Aluminium Anodes
PublicationAl-Zn-In alloys having 4.2% zinc content and various indium content in the range of 0.02–0.2% were tested with respect to the most important electrochemical properties of sacrificial anodes in a cathodic protection, i.e., the current capacity and potential of the operating anode. The distribution of In and Zn in the tested alloys was mapped by means of the EDX technique, which demonstrated that these elements dissolve well in the...
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Modeling by finite element methods of impact of erosion on frequency of normal modes of L-0 blade
PublicationAfter some time of exploitation steam turbine rotors blades in energetic industry they are being eroded and also their frequency of normal modes is changed. Those changes can cause to unwanted shift of blades normal mode frequencies. It is necessary to find quick method of rating changes of frequency in connection of mass loss due erosion. The evaluation of this dependence was made by finite element modeling method using HyperWorks...
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Efficient Complex Root Finding Algorithm for Microwave and Optical Propagation Problems
PublicationArticle relates to the use of innovative root finding algorithm (on a complex plane) to study propagation properties of microwave and optical waveguides. Problems of this type occur not only in the analysis of lossy structures, but also in the study of complex and leaky modes (radiation phenomena). The proposed algorithm is simple to implement and can be applied for functions with singularities and branch cuts in the complex plane...
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Pin-on-Substrate Gap Waveguide: An Extremely Low-Cost Realization of High-Performance Gap Waveguide Components
PublicationConsidering the limitations of currently available technologies for the realization of microwave components and antennas, a trade-off between different factors including the efficiency and fabrication cost is required. The main objective of this letter is to propose a novel method for the realization of gap waveguides (GWGs) that take advantage of conventional PCB fabrication technology, thus are low cost and light weight. Moreover,...
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Using wavelet techniques for multibeam sonar bathymetry data compression
PublicationMultibeam sonars are widely used in applications like high resolution bathymetry measurements or underwater object imaging. One of the significant problems in multibeam sensing of the marine environment is large amount of data which must be transmitted from the sonar processing unit to an operator station using a limited bit rate channel. For instance, such a situation would be in the case when the multibeam sonar was mounted on...
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On the compression of multibeam sonar raw bathymetry data
PublicationMultibeam sonars are widely used in applications like high resolution bathymetry measurements or underwater object imaging. One of the significant problems in multibeam sensing of the marine environment is large amount of data which must be transmitted from the sonar processing unit to an operator station using a limited bit rate channel. For instance, such a situation would be in the case when the multibeam sonar was mounted on...
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Miasta na prawach powiatu z rozwiniętym przemysłem jako lokalne ośrodki rozwoju na obszarach peryferyjnych polskich regionów
PublicationMost of the growth factors is situated in big cities, especially in metropolitan areas. Questions arise: 1) Whether and what development factors are in the peripheral areas of voivodeships (i.e. outside the functional areas of their capitals)? 2) Can the industry be the driving force of the development of these areas? These questions are related to the discussion on the reindustrialisation of the European Union and the role of...
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Sustainable Urban Mobility Plans: implementation process and indicators to evaluate effects on physical activity
PublicationBackground: Active mobility and public transport increase physical activity (PA) levels. With varying intensity and effectiveness, European cities implement Sustainable Urban Mobility Plans (SUMPs) to spur transport-related PA. Therefore, we aim to examine drivers and barriers to SUMP implementation and assess its influence on PA across European cities. Methods: We screened policy reports to gain insights into SUMP implementation...
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An Empirical Model for the Polarisation Characteristics of Indoor Off-Body Channels
PublicationThis paper presents an analysis of the polarisation characteristics for the channel in dynamic off-body communications, and an empirical channel model, based on measurements performed at 2.45 GHz in an office environment. Body presence and propagation conditions have a strong influence on signal depolarisation. The model assumes three components for the total path loss: mean path loss, represented by a log-distance function with...
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MIASTO PORTOWE – STRUKTURA, WYZWANIA FUNKCJONALNE I MODELE ROZWOJU
PublicationPort cities are having different spatial structure than those located inlands. As a result of their seaside location, they face specific administrative and functional problems on a daily basis. In the economic and settlement structure of the country, they usually play the role of a "gate" through which streams of cargo are distributed further over the whole hinterland. It is the transport and logistics function of port cities,...
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Effect of Thermal Treatment and Erosion Aggressiveness on Resistance of S235JR Steel to Cavitation and Slurry
PublicationS235JR steel is used in many applications, but its resistance to the erosion processes has been poorly studied. To investigate this resistance, cavitation, and slurry erosion tests were conducted. These tests were carried out at different erosion intensities, i.e., different flow rates in the cavitation tunnel with a system of barricades and different rotational speeds in the slurry pot. The steel was tested as-received and after...
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GPU Power Capping for Energy-Performance Trade-Offs in Training of Deep Convolutional Neural Networks for Image Recognition
PublicationIn the paper we present performance-energy trade-off investigation of training Deep Convolutional Neural Networks for image recognition. Several representative and widely adopted network models, such as Alexnet, VGG-19, Inception V3, Inception V4, Resnet50 and Resnet152 were tested using systems with Nvidia Quadro RTX 6000 as well as Nvidia V100 GPUs. Using GPU power capping we found other than default configurations minimizing...
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A Robust Random Forest Model for Classifying the Severity of Partial Discharges in Dielectrics
PublicationPartial Discharges (PDs) are a common source of degradation in electrical assets. It is essential that the extent of the deterioration level of insulating medium is correctly identified, to optimize maintenance schedules and prevent abrupt power outages. Temporal PD signals received from damaged insulation, collected through the IEC-60270 method is the gold standard for PD detection. Temporal signals may be transformed to the frequency...
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Characterization of Defects Inside the Cable Dielectric With Partial Discharge Modeling
PublicationThe continuous monitoring of power system devices is an important step toward keeping such capital assets safe. Partial discharge (PD)-based measurement tools provide a reliable and accurate condition assessment of power system insulations. It is very common that voids or cavities exist in every solid dielectric insulation medium. In this article, different voids are modeled and analyzed using an advanced finite element (FE)-based...
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Pier of the future- investigation of green and blue strategies as tools for modernization of Gdynia's public waterfront
PublicationBetween rising water levels and global migration to cities, architects and designers need to critically reimagine the relationship between coastal landscapes and public space. Cities are facing entirely new risks and environmental conditions. Resiliency, infrastructure, and ecology are increasingly common terms, reflecting the growing demand to address the spatial and formal challenges faced by cities worldwide. Rethinking boundaries...
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Semantic Driven Table Understanding in Born-Digital Documents
PublicationThis paper presents a new approach to table understanding, suitable for born-digital PDF documents. Advance beyond the current state of the art in table understanding is provided by the proposed reverse MVC method, which takes advantage of only partial logic structure loss (degradation) in born-digital PDF documents, as opposed to unrecoverable loss (deterioration) taking place in scan based PDF documents.
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Microwave Alignment and Displacement Sensors in Groove Gap Waveguide Technology
PublicationThis paper is aimed at presenting highly sensitive microwave displacement and alignment sensors. With this goal, the method of realizing mechanically tunable cavity resonators in groove gap waveguides technology is presented. The resonance frequency of the cavity is then used for displacement sensing. It is also demonstrated that the symmetry properties of a pair of groove gap waveguide cavities can be used to improve the robustness...
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Statistical Tuning of Walfisch-Ikegami Model for the Untypical Environment
PublicationThe Walfisch-Ikegami model has been investigated in terms of mobile radio systems designing in the untypical environment such as the maritime container terminal. The measurement equipment and procedures have been described as well as characteristics of investigated environment. Results of the statistical tuning in terms of path loss estimation in such environment have been analysed. The analysis has proved improvement of the path...
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Statistical Tuning of Walfisch-Ikegami Model for the Untypical Environment
PublicationThe Walfisch-Ikegami model has been investigated in terms of mobile radio systems designing in the untypical environment such as the maritime container terminal. The measurement equipment and procedures have been described as well as characteristics of investigated environment. Results of the statistical tuning in terms of path loss estimation in such environment have been analysed. The analysis has proved improvement of the path...
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Selected Propagation Models Modification for Application in Container Terminal
PublicationIt is particularly important to look for any propagation model that could be useful for designing mobile radio systems in container terminal environment. The selected propagation models have been investigated. The applied research methodology has been described too. Results of the statistical adjustment in terms of signal loss determination in such environment have been analysed. The analysis have proved effectiveness of adjustment...
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Empirical Adjustment of the Selected Propagation Models for Application in the Peculiar Environment of the Container Terminal
PublicationIt is important to look for any propagation model that could be useful for designing mobile radio systems in container terminal environment. Selected propagation models have been investigated. The applied research methodology has been described too. Results of the statistical adjustment in terms of signal loss determination in such environment have been analysed. The analysis has proved effectiveness of adjustment by increasing...
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Protect our right to light
Publication“The struggle for light” is how the Swiss architect Le Corbusier described the history of architecture in 1935. Today, with the skies crowded out by buildings in modern cities, those words should ring in the ears of policymakers and planners. Skyscraper construction is booming. China is the leader, last year completing 88 of the 143 buildings around the world that are taller than 200 metres (see ‘Vertical growth’). As the nation’s...
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MSRL and the Real-Life Processes of Capturing and Implementing the "Urban Innovation"
PublicationResult of the MSRL workshop, five research projects, reflect on a broader process of exchange of the ideas between the cities, that is occurring in the real life and became one of the driving factors of the urban development nowadays. The objective of the MSRL research - concepts, which help to advance the development of the cities, support the improvement of the quality of urban environment or meet the future challenges, can be...
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Low energy electron mass stopping power in H2
PublicationWe present experimental mass stopping powers of electrons in gaseous H2 obtained with a newly developed electron time-of-flight spectrometer, for the incident electron energy range of 10eV to 25eV. In our procedure the average energy loss is derived from our conversion of measured electron time-of-flight spectra into equivalent electron energy loss spectra so as to obtain the values of mass stopping power for electron scattering...
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Pipeline geometry defects in high resolution pig's data
PublicationMost of the pipelines have been inspected at least once using intelligent pigging. The problem of specific software for interactive presentation, analysis and comparison of features revealed during the consecutive geometry surveys is emphasized. Capabilities of a simultaneous measurement of internal geometry and metal loss features in a single run are illustrated. Advantages of application of statistical characteristics of both...
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Can the Pandemic Be a Catalyst of Spatial Changes Leading Towards the Smart City?
PublicationThe worldwide spread of Covid‐19 infections has had a pervasive influence on cities and the lives of their residents. The current crisis has highlighted many urban problems, including those related to the functionality of urban structures, which directly affect the quality of life. Concurrently, the notion of “smart cities” is becoming a dominant trend in the discourse on urban development. At the intersection of these two phenomena,...
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Efficiency limit of excitonic photovoltaic cells under phosphor-based white LED illumination
PublicationThe limit of energy conversion of excitonic photovoltaic cells working under white light illumination generated by phosphor-based LED is analysed using the modified Giebink approach. Particularly, the impact of the optical energy gap and energy loss associated with the excitons dissociation at the heterojunction interface on power conversion efficiency of the device are discussed. From the results of our study it follows that the...
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Architektoniczne tożsamości miasta portowego - na przykładach Gdańska i Gdyni oraz Hamburga i Altony
PublicationHarbour cities of Northern Europe, especially those growing in the circle of influence of Hanseatic League, were formed in a way, which allows to identify them as the cities of a specific identity considering architecture and urban planning. Industrial revolution of 19-th and early 20-th century brought the radical change in the field of spatial development of the cities. Economical, political, cultural influences, also social...
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Water related esthetics - the phenomenon of new structure in the post industrial shipyard areas
PublicationDirection of the main movements that are made in the European cities determines not only structural but also an esthetic changes. Paper follows the topic of visual diversity of post industrial waterfront cities and it’s relation to the local identity and cultural changes that are provided. Reshaping of the cities continuously proceed. Are those changes related with industrial shipyard districts only economical and spatial or also...
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A Method for Optimising the Blade Profile in Kaplan Turbine
PublicationThis paper introduces a method of blade profile optimisation for Kaplan-type turbines, based on modelling the interaction between rotor and stator blades. Rotor and stator blade geometry is described mathematically by means of a midline curve and thickness distribution. Genetic algorithms are then used to find a global optimum that minimises the loss coefficient. This allows for variety of possible blade shapes and configurations....
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On the approximation of the UWB dipole elliptical arms with stepped-edge polygon
PublicationA simple method of approximation of the ellipticalpatch with stepped-edge polygon is proposed as an introductionto wider studies over the planar ultrawideband (UWB) antennas.The general idea is to replace the elliptical patch with an equivalentpolygonal patch, with minimum loss in the performance. Theprinciples of the proposed method are presented in this letter, aswell as the results of performed numerical studies and its experimentalverification....
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Experimental determination of H2 mass stopping powers for low-energy electrons
PublicationWe present experimental mass stopping powers of electrons in gaseous H2 obtained with an electron time- of-flight spectrometer, for the incident electron energy range of 11 to 25 eV. In our procedure, the average energy loss is derived from conversion of the measured electron time-of-flight spectra into equivalent electron energy-loss spectra. Our present results are compared with the only available experimental measurement and...
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A repeated game formulation of network embedded coding for multicast resilience in extreme conditions
PublicationComputer networks and data sharing applications are vital for our current society and fundamental for any available ICT solution, so that networking is considered as one of the key critical infrastructures and its correct behavior should be always enforced, even in case of disasters or severe execution conditions. Resilience is a strongly demanding nonfunctional requirement for current computer networks, and one of the key factors...
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MORPHOLOGY OF BUILDING DEVELOPMENT AS AN ELEMENT OF URBAN VENTIALTION SYSTEM
PublicationProblems related to air quality in large urban agglomerations (e.g., high concentration of pollutants, the urban heat island phenomenon) make it necessary to take comprehensive measures to improve air exchange in urban areas.The article concerns the relationship between wind phenomena observable in cities and the geometrical features of building development. The knowledge on the subject is already well-founded and has been intensively...
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Modeling of multi-cavity Fabry-Perot optical fiber sensors
PublicationReflectance characteristics of a two-cavity extrinsic Fabry-Perot optical fiber sensor were investigated using computer modeling. Calculations were performed using a plane wave-based approach, selected for clarity of results. Based on the modeling results, it can be concluded that the two-cavity Fabry-Perot interferometer can be used to measure two different quantities, such as refractive index and temperature, independently. It...
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The Contemporary aspects of revitalization of the buildings and the port areas
PublicationPort cities are the forefront of globalization. The continued growth of international trade of goods and services has now played a major role in shaping the economic and social world. Strategies for mutual cooperation and follow-up between countries, cities and regions are increasingly complex. On the one hand it brings profits, on the other leads to destabilization and the need for transformation and constant modernization. Port...
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DenCity – a Pan-European Future
PublicationThe paper considers interrelations between density and quality of life in European cities.
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Education programmes as an element of limiting space and social barriers.CTA Home : Accessible Transportation : TRANSED 2007 [online]. [dostęp 2007.12.31]. Dostępny w World Wide Web: http: //www.tc.gca.ca - TRANSED 2007 COMOTRED
PublicationThe article presents education programme " Creating common space" introduced by Gdansk University of Technology - Architecture Department ( Poland) and local authorities. It also contains workshops " Cities without barriers" carried out in Pomeranian cities, where students are taught an additional subject " Designing common space". Liquidation of space barriers is necessary to help the disabled live their lives, develop and become...
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Social perception of technological innovations at sports facilities: justification for financing ‘white elephants’ from public sources? The case of Euro 2012 Stadiums in Poland
PublicationThe main purpose of the paper is to provide a monetary valuation of social benefits in connection with the hypothetical implementation of technological innovations at four Euro 2012 stadiums in Poland. Not only the construction of the sport’s arenas, but also the ongoing maintenance drain the pockets of Polish taxpayers. At the same time Euro 2012 stadiums remain underused, which familiarize the host cities with the concept of ‘white...
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Exergy and Energy Analyses of Microwave Dryer for Cantaloupe Slice and Prediction of Thermodynamic Parameters Using ANN and ANFIS Algorithms
PublicationThe study targeted towards drying of cantaloupe slices with various thicknesses in a microwave dryer. The experiments were carried out at three microwave powers of 180, 360, and 540 W and three thicknesses of 2, 4, and 6 mm for cantaloupe drying, and the weight variations were determined. Artificial neural networks (ANN) and adaptive neuro-fuzzy inference systems (ANFIS) were exploited to investigate energy and exergy indices of...
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Zmiany przestrzenne w miastach wywołane pandemią COVID-19 a przestrzenny wymiar rewitalizacji.
PublicationThe COVID-19 pandemic affects every aspect of the modern world on a global and local scale. Part of the fight against the virus was, among other things, limiting the possibility of movement. In cities, this has resulted in a focus on the spatial aspects of the urbanized environment. The article aims to analyse spontaneous actions taken in cities to mitigate the effects of a pandemic concerning strategic activities...
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Historic Urban Settings, LED Illumination and its Impact on Nighttime Perception, Visual Appearance, and Cultural Heritage Identity
PublicationMany cities, towns and villages around the world have adopted new Lighting Emitting Diode (LED) technology in order to save energy, operational and maintenance costs. While energy-efficient, these light sources have a critical effect on the appearance of historic sites at night and the technology has unique properties and numerous inherent drawbacks that present challenges to decision makers as well as inexperienced lighting...
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A Substrate Integrated Waveguide (SIW) Bandpass Filter in A Box Configuration With Frequency-Dependent Coupling
PublicationThis letter presents the design of a microwave bandpass filter with frequency-dependent coupling implemented in substrate integrated waveguide (SIW) technology. The proposed filter implements a four-pole generalized Chebyshev filtering function with two transmission zeros. Resonators are arranged in an extended box configuration with dispersive coupling on a main signal path, which produces an extra zero in comparison to classical...
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Eksperymentalna analiza współczynników oporów lokalnych dla wybranych kształtek i złączek w systemach rur wielowarstwowych
PublicationArtykuł poświęcony jest analizie wartości współczynników oporów lokalnych dla wybranych kształtek i złączek pracujących w instalacjach z rur wielowarstwowych z tworzyw sztucznych. Badaniom poddano elementy o średnicach DN16, DN20, DN25, powszechnie wykorzystywane we współczesnych instalacjach sanitarnych. W pracy przedstawiono wybrane wyniki badań laboratoryjnych (dla rozszerzeń, kolanek i trójników) oraz ich porównanie z wartościami...
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The Rule-Based Model of Negentropy for Increasing the Energy Efficiency of the City’s Digital Transformation Processes into a Smart City
PublicationThe aim of the article is to build a rule-based model (RMFDN) for increasing the energy efficiency of Smart Cities’ digital transformation processes. The problem that arises during the implementation of digital transformation processes concerns the measures that should be assigned to estimate the duration of the digital transformation. Previous studies of digital transformation have been based on the analysis of design processes...
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FAILURE OF MAGNETIC FLUID SEALS OPERATING IN WATER: PRELIMINARY CONCLUSIONS
PublicationThe article analyses properties of magnetic fluid seals installed in rotary sealing no des which operate in the utility water environment. Seals of this type have been examined as a possible solution to the problem with ship manoeuvring propulsion sealing. The present analysis bases on laboratory durability tests of magnetic fluid seals expo sed to long - term utility water loads, at different water pressures and shaft revolutions....