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The role of ergonomics in architectonic and marketing operations
PublikacjaThe 20th century, along with the development of mass culture, brought a rapid increase of marketing communications significance. At first, this branch of art had an informational function associated with advertising operations. Nowadays, an increase of marketing specialists’ interest in influencing a human being by the space they stay in may be observed. Ergonomics plays an important role in such operations. The aim of this article...
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Flow Control Algorithm for UMTS HSDPA
PublikacjaHSDPA (High Speed Downlink Packet Access) jest istotnym etapem ewolucji systemu UMTS. Pozwala na transmisję do użytkownika z prędkością dochodzącą do 14.4 Mbit/s; aby to umożliwić, wprowadzono w wersji 5 UMTS szereg nowych mechanizmów w warstwie fizycznej oraz MAC. W tej pracy przedstawiono szczegółową analizę jednego z nowych mechanizmów - algorytmu kontroli natężenia ruchu między MAC-hs i MAC-d. Zaproponowano nowy, efektywny...
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Experimental study of the multi-disc negative brake for a hydraulic motor
PublikacjaThis paper describes the methodology for experimental testing of a multi-disc brake. The construction of this brake was also present. The brake is dedicated to hydraulic motors with a small working volume. Experimental tests were carried out on a brake with plates immersed in oil and, for comparison, tests were carried out on a dry brake. As a result of the tests, the permissible torque (load) that is able to transfer the brake...
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Extended duration running and impulse loading characteristics of an acoustic bearing with enhanced geometry
PublikacjaThis paper presents performance during prolonged running of the acoustic bearing when PZTs are switched off and when they are switched on. The effect of active PZT on shaft’s displacements in X and Y directions is clearly demonstrated. Performance of the acoustic bearing was also assessed when an impulse force was applied to the running shaft at speed. Once again the benefits of having PZTs active are beyond doubt. The instability...
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A correlation between electron-hole pair radii and magnetomodulation of exciplex fluorescence in electron donor-electron acceptor organic systems
PublikacjaElectric field dependencies of electromodulated photoluminescence and magnitudes of the magnetic-field effect on photoluminescence havebeen measured in vacuum-evaporated films of m-MTDATA [4,4',4"-tris(N-(3-methylphenyl)-N-phenylamino)triphenylamine]:bathophe-nanthroline, m-MTDATA:BCP (bathocuproine), as well as 4,4',4"-tris[2-naphthyl(phenyl)amino]triphenylamine:BCP. The Sano-Tachiya-Noolandi-Hong extension of standard Onsager...
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Continuous wave sonar with hyperbolic frequency modulation keyed by pseudo-random sequence
PublikacjaA CW FM type sounding signal is used in the classical solution of silent sonar. While the signal provides a relatively simple implementation of digital signal processing, and ensures good detection conditions, unfortunately, in the presence of the Doppler effect, distance measurement results tend to be wrong. This is due to the fact that the received signal’s instantaneous frequency value is dependent both on the distance to the...
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The role of water in deep eutectic solvent-base extraction
PublikacjaDeep eutectic solvents (DESs) are currently being used in different sectors, such as electrochemistry, electrodeposition, organic synthesis, nanoparticle preparation, bioactive compound separation, etc. Their use in analytical chemistry has only recently begun to expand. Despite the publication of a sufficient number of DES-based analytical extraction procedures, some details, such as interaction of DESwith the sample and target...
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China’s international trade and global value chains under One-Belt One-Road initiative
PublikacjaResearch background: After China acceded to the WTO in 2001, its foreign trade has expanded rapidly to be the largest share in the world. However, China's economic development changing from high-speed growth to medium high-speed growth in recent years. At the same time, the increase in labour cost and overcapacity also hinder China’s international trade. In order to solve these challenges and strengthening ties...
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Pedestrian Safety at Midblock Crossings on Dual Carriageway Roads in Polish Cities
PublikacjaRoad crossings across two or more lanes in one direction are particularly dangerous due to limited sight distance and high vehicle speeds. To improve their safety, road authorities should provide safety treatments. These may include additional measures to reduce speed and narrow the road cross-section and the introduction of active pedestrian crossings. Equipped with flashing lights activated automatically when a pedestrian is...
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Ecological bearing systems for water turbines – research and development at Gdansk University of Technology
PublikacjaIncreasing requirements for environmental protection make it necessary to introduce new materials and designs. Hydroelectric power plants operating in direct contact with water reservoirs and rivers are potentially endangering water cleanliness, hence they should also be modernized in the way minimizing the environmental hazards. A lot of progress in this field has been achieved in last decades, but still there is much work to...
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Towards Designing an Innovative Industrial Fan: Developing Regression and Neural Models Based on Remote Mass Measurements
PublikacjaThis article presents the process of the construction and testing a remote, fully autonomous system for measuring the operational parameters of fans. The measurement results obtained made it possible to create and verify mathematical models using linear regression and neural networks. The process was implemented as part of the first stage of an innovative project. The article presents detailed steps of constructing a system to...
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Augmented Reality for Privacy-Sensitive Visual Monitoring
PublikacjaThe paper presents a method for video anonymization and replacing real human silhouettes with virtual 3D figures rendered on the screen. Video stream is processed to detect and to track objects, whereas anonymization stage employs fast blurring method. Substitute 3D figures are animated accordingly to behavior of detected persons. Their location, movement speed, direction, and person height are taken into account during the animation...
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An Analog Sub-Miliwatt CMOS Image Sensor With Pixel-Level Convolution Processing
PublikacjaA new approach to an analog ultra-low power medium-resolution vision chip design is presented. The prototype chip performs low-level image processing algorithms in real time. Only a photo-diode, MOS switches and two capacitors are used to create an analog processing element (APE) that is able to realize any convolution algorithm based on a full 3x3 kernel. The proof-of-concept circuit is implemented in 0.35 µm CMOS technology,...
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Fractional Order Dynamic Positioning Controller
PublikacjaImproving the performance of Dynamic Positioning System in such applications as station keeping, position mooring and slow speed references tracking requires improving the position and heading control precision. These goals can be achieved through the improvement of the ship control system. Fractional-order calculus is a very useful tool which extends classical, integer-order calculus and is used in contemporary modeling and control...
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Disturbances of Earth magnetic field caused by eddy currents of airplane
PublikacjaThe uniform magnetic field of the Earth in the surrounding of a mobile, metallic object undergoes deformation by eddy currents. The influence of the moving, conducting object on the Earth's total magnetic field depends on the object's shape, position and speed of the changes relative to the magnetic field vector of the Earth, as well as the electric conductivity and the relative magnetic permeability of the material. Disturbances...
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Diffusible hydrogen management in underwater wet self-shielded flux cored arc welding
PublikacjaThis article reports the effect of underwater wet welding parameters and conditions on the diffusible hydrogen content in deposited metal for welding with a self-shielded flux cored wire. The diffusible hydrogen content in deposited metal was determined using the glycerin method according to the Plackett-Burman design determining the significance of the effect of the stick out length, welding current, arc voltage, travel speed...
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Multi-objective Weather Routing with Customised Criteria and Constraints
PublikacjaThe paper presents a weather routing algorithm utilising a multi-objective optimisation with constraints, namely the Multi-objective Evolutionary Weather Routing Algorithm (MEWRA). In the proposed approach weather route recommendations can be made simultaneously e.g. for passage time, fuel consumption and safety of passage by means of Pareto optimisation. The sets of criteria and constraints in the optimisation process are fully...
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SELECTED COMBINED POWER SYSTEMS CONSISTED OF SELFIGNITION ENGINE AND STEAM TURBINE
PublikacjaThis paper presents optimization of selected combined diesel engine-steam turbine systems. Two systems: the system combined with waste heat one-pressure boiler only and its version containing additionally low-pressure boiler proper feeding degasifier and the system of two-pressure cycle, were taken into considerations. Their surplus values of power output and efficiency associated with utilization of waste heat contained in piston...
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Analysis of Denoising Autoencoder Properties Through Misspelling Correction Task
PublikacjaThe paper analyzes some properties of denoising autoencoders using the problem of misspellings correction as an exemplary task. We evaluate the capacity of the network in its classical feed-forward form. We also propose a modification to the output layer of the net, which we called multi-softmax. Experiments show that the model trained with this output layer outperforms traditional network both in learning time and accuracy. We...
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An assessment of teeth quality of the mini gang saw blade
PublikacjaIn this work, the assessment of the effect of the operating time (90 min.) of the mini gang saw blades during sawing Scotch pine (Pinus sylvestris L.) samples upon changes of the saw blade teeth sharpness (bluntness), which was defined as an effective radius of the nose ρ , has been described. The research activities have been carried out on the Nikon Ti-S optical microscope equipped with the Nikon DS-30W camera allowing high-speed...
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Multistatyczny, Dopplerowski System określania położenia i prędkości ruchomych celów w wodzie
PublikacjaW omawianym w pracy multistatycznym, dopplerowskim systemie określania położenia i prędkości ruchomych celów w wodzie źródłem sygnału są dwa nadajniki emitujące sinusoidalne, akustyczne fale ciągłe o różnych częstotliwościach, które po odbiciu od ruchomego celu są obierane przez cztery hydrofony. W artykule przedstawiono analize teoretyczna efektu Dopplera, na którym oparte jest działanie systemu oraz metodę rozwiązania głównych...
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Transient modeling in common DC link of power converters
PublikacjaПредмет исследования. Представлена математическая модель силовых преобразователей электропривода, питающихся от общего звена постоянного тока, на примере тяговых электроприводов карьерного самосвала БЕЛАЗ-90 мощностью 280 кВт. Модель выполнена в пакете MATLAB/Simulink. Новизна предложенной модели заключается в применении новой топологии силовой схемы для исследования работы двух инверторов, под- ключенных к одному звену постоянного...
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3D scanning system for railway current collector contact strips
PublikacjaUndisturbed collection of current from a contact wire of the catenary constitutes one of the basic elements in reliable operation of electrified rail transport, particularly when vehicles move at high speed. Quality of current collection is influenced by the construction of catenary and current collectors, as well as by the technical condition and regulation of these two elements. Total contact force of a current collector head...
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Multilevel model order reduction with generalized compression of boundaries for 3-d FEM electromagnetic analysis
PublikacjaThis paper presents a multilevel Model Order Reduction technique for a 3-D electromagnetic Finite Element Method analysis. The reduction process is carried out in a hierarchical way and involves several steps which are repeated at each level. This approach brings about versatility and allows one to efficiently analyze complex electromagnetic structures. In the proposed multilevel reduction the entire computational domain is covered...
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THE INFLUENCE OF WSR PARAMETER ON PET BOTTLE THICKNESS PROFILE IN SBM FROM PREFORM PROCESS
PublikacjaFrom a mechanical point of view, the thickness profile of PET bottles manufactured by ISBM process is determined by mechanical and thermal response of blown preforms. From the microscopic point of view the biggest influence on the mechanical and thermal properties of PET bottles have orientation and crystallization processes. From a technological point of view, the thickness profile of PET bottles after manufacture by SBM process...
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Hierarchical Estimation of Human Upper Body Based on 2D Observation Utilizing Evolutionary Programming and 'Genetic Memory'
PublikacjaNew method of the human body pose estimation based on single camera 2D observation is presented. It employs 3D model of the human body, and genetic algorithm combined with annealed particle filter for searching the global optimum of model state, best matching the object's 2D observation. Additionally, motion cost metric is employed, considering current pose and history of the body movement, favouring the estimates with the lowest...
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Construction of phylogenetic trees with topological constraints
PublikacjaThis paper proposes a method of reconstruction of phylogenetic trees based on heuristic search with topological constraints. Using topological constraints it is possible to reduce the set of solutions as well as to enforce that the result is consistent with a given hypothesis about the evolution process within some group of species. Along with this work a number of algorithms used for phylogenetic analysis were implemented. Those...
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Fast Calibration-Free Single-Anchor Indoor Localization Based on Limited Number of ESPAR Antenna Radiation Patterns
Publikacja— In this article, we investigate how the calibrationfree single-anchor indoor localization algorithm developed for base stations equipped with electronically steerable parasitic array radiator (ESPAR) antennas can further be improved. By reducing the total number of ESPAR antenna radiation patterns used in localization process, one can significantly reduce the time needed for an object localization. Performed localization measurements...
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Creating a more conscious built environment for day- and night-time setting through interdisciplinary collaboration
PublikacjaThe last decades have seen an increase in the speed, scale and scope of urbanisation, fundamentally shifting the character of the built environment and engendering a radical search for new and resilient design practices. Although we, as society, live in the age of technology, inventions and almost unlimited access to information, we rarely use these opportunities to our advantage to improve the quality of life. It seems that multidisciplinary...
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Safety Assessment of the Regional Warmia and Mazury Road Network Using Time-Series Analysis
PublikacjaWarmia and Mazury still belongs to the areas with the smallest transport accessibility in Europe. Unsatisfactory state of road infrastructure is a major barrier to the development of the regional economy, impacting negatively on the life conditions of the population. Also in terms of road safety Warmia and Mazury is one of the most endangered regions in Poland. The Police statistics show that beside a high pedestrian risk observed...
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Road surface roughness estimation employing integrated position and acceleration sensor
PublikacjaAssessment of a surface quality being an essential task for the authorities supervising the roads provides the subject of the paper. Information about riding quality of a pavement, important for drivers, both in terms of their comfort and safety is collected during experiments employing mobile sensors. The paper describes the use of a miniature position and acceleration sensor for evaluation of the roughness of the road surface....
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Experimental research on a hydrodynamic thrust bearing with hydrostatic lift pockets: Influence of lubrication modes on bearing performance
PublikacjaThe aim of the study is to investigate the performance of a thrust bearing equipped with hydrostatic lift pockets under different lubrication modes. Three types of flat land bearing lubrication modes are studied experimentally: hydrostatic lubrication (HS; forced oil injection to the pockets), hybrid lubrication (HS + HD; hydrostatic lubrication combined with the external forced bearing oil supply) and hydrodynamic lubrication...
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Adaptacyjny system sterowania ruchem drogowym
PublikacjaAdaptacyjny system sterowania ruchem drogowym to rodzaj systemu sterowania, który dynamicznie, w czasie rzeczywistym, dostosowuje swoje parametry w oparciu o bieżące warunki ruchu drogowego. Celem niniejszej rozprawy jest sprawdzenie wpływu wybranych cech systemu, zbudowanego w oparciu o zaprojektowane i zbudowane z udziałem autora inteligentne znaki drogowe, na wybrane parametry mające wpływ na bezpieczeństwo i płynność ruchu....
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G2DC-PL+: a gridded 2 km daily climate dataset for the union of the Polish territory and the Vistula and Odra basins
PublikacjaG2DC-PL+, a gridded 2 km daily climate dataset for the union of the Polish territory and the Vistula and Odra basins, is an update and extension of the CHASE-PL Forcing Data – Gridded Daily Precipitation and Temperature Dataset – 5 km (CPLFD-GDPT5). The latter was the first publicly available, high-resolution climate forcing dataset in Poland, used for a range of purposes including hydrological modelling and bias correction of...
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Why are trees still such a major hazard to drivers in Poland?
PublikacjaRoadside trees are one of Poland's most serious road safety issues. Since 2009 more than 2800 people have been killed as a result of tree collisions; this represents about 15% of all of Poland's accident fatalities between 2009 and 2013. In some of the country's regions striking a tree caused more than 30% of all road accident fatalities. With no proper regulations, guidelines or examples of good practice, roadside environments...
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Real-time hybrid model of a wind turbine with doubly fed induction generator
PublikacjaIn recent years renewable sources have been dominating power system. The share of wind power in energy production increases year by year, which meets the need to protect the environment. Possibility of conducting, not only computer simulation, but also laboratory studies of wind turbine operation and impact on the power system and other power devices in laboratory conditions would be very useful. This article presents a method...
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ISSUES OF ECONOMIC ANALYSIS OF ELECTRIC ENERGY GENERATION IN A FLOATING POWER PLANT
PublikacjaThis article presents basic dependences for conducting a technical and economic analysis related with investment projects. It describes a combined system of a compression ignition engine and a steam turbine, whose aim, when placed on a floating platform, is to generate electric energy in the so-called distributed generation system. Such a system involves a reciprocating internal combustion engine and a connected steam turbine system...
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Influence of external climate on natural ventilation performance in buildings
PublikacjaNatural ventilation is driven by either buoyancy forces or wind pressure forces or their combinations that inherit stochastic variation into ventilation rates [ CITATION Hun99 \l 1045 ]. We now that these factors have influence on air flow speed and thermal comfort inside building. This work examines the relationship between external climate and natural ventilation including thermal comfort. The work tries in the first instance...
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A Fail-Safe NVRAM Based Mechanism for Efficient Creation and Recovery of Data Copies in Parallel MPI Applications
PublikacjaThe paper presents a fail-safe NVRAM based mechanism for creation and recovery of data copies during parallel MPI application runtime. Specifically, we target a cluster environment in which each node has an NVRAM installed in it. Our previously developed extension to the MPI I/O API can take advantage of NVRAM regions in order to provide an NVRAM based cache like mechanism to significantly speed up I/O operations and allow to preload...
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"Shadow" method application within endoscopic examinations of marine engines
PublikacjaThe paper deals with diagnostic issues concerning endoscopic examinations of the working spaces within marine diesel and gas turbine engines. In the beginning, the endoscopy apparatus being on the laboratory equipment of the Department of Ship Power Plants of Gdansk University of Technology in Poland has been characterized. The endoscopy considerations have been focused on theoretical bases of a digital image processing and especially...
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"Shadow" method application within endoscopic examinations of marine engines
PublikacjaThe paper deals with diagnostic issues concerning endoscopic examinations of the working spaces within marine diesel and gas turbine engines. In the beginning, the endoscopy apparatus being on the laboratory equipment of the Department of Ship Power Plants of Gdansk University of Technology in Poland has been characterized. The endoscopy considerations have been focused on theoretical bases of a digital image processing and especially...
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The hydrodynamic pressure field of the ship Zodiak, measurements and calculations
PublikacjaThe article presents the results of measurements of the slowly changing hydrodynamic pressure field HPF generated by the movement of the ship, Zodiak, in the Bay of Gdansk. The measurement results have been obtained in the framework of the program of the work in Siramis, under the auspices of the European Defence Administration of the EU, by the research team of the Naval Academy in Gdynia. The measurement results were compared with...
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Use of the AHP Method for Preference Determination in Yacht Design
PublikacjaA sailing yacht is a human-centred product, the design of which revolves primarily around the wants and desires of the future owner. In most cases, these preferences are not measurable, such as a personal aesthetic feeling, or a need for comfort, speed, safety etc. The aims of this paper are to demonstrate that these preferences can be classified and represented numerically, and to show that they are correlated with the type...
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Creating Acoustic Maps Employing Supercomputing Cluster
PublikacjaThe implemented online urban noise pollution monitoring system is presented with regard to its conceptual assumptions and technical realization. A concept of the noise source parameters dynamic assessment is introduced. The idea of noise modeling, based on noise emission characteristics and emission simulations, was developer and practically utilized in the system. Furthermore, the working system architecture and the data acquisition...
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Investigations of Aerodynamics of Tesla Bladeless Microturbines
PublikacjaThe paper presents an analysis of a Tesla bladeless turbine for a co-generating micro-power plant of heat capacity 20 kW, whichoperates in an organic Rankine cycle with a low-boiling medium. Numerical calculations of flow in several Tesla turbine models areperformed for a range of design parameters. Results of investigations exhibit interesting features in the distribution of flowparameters within the turbine interdisk space. The...
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Energy efficient beam control for 5G antennas
PublikacjaThe rapid development of 5G and beyond systems demands improvement in communication speed, latency and safety to maintain the required quality of service. This paper presents an overview of different concepts of energy-efficient antenna systems, which offer beam-shaping and beam-steering functionalities, that enhance connectivity performance and can be used in 5G applications. Different designs for 5.9 GHz, 39 GHz and 60 GHz frequency...
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Use of the AHP Method for Preference Determination in Yacht Design
PublikacjaA sailing yacht is a human-centred product, the design of which revolves primarily around the wants and desires of the future owner. In most cases, these preferences are not measurable, such as a personal aesthetic feeling, or a need for comfort, speed, safety etc. The aims of this paper are to demonstrate that these preferences can be classified and represented numerically, and to show that they are correlated with the type of...
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Fluid–solid interaction on a thin platelet with high-velocity flow: vibration modelling and experiment
PublikacjaThe paper concerns the nonlinear behaviour of a thin platelet that is streamlined in an aerodynamic tunnel. The air velocity in the aerodynamic tunnel was at 858.9 km/h or 0.7 Ma (Ma—Mach number is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a boundary to the local speed of sound). This experiment was numerically simulated using FSI (fluid–solid interaction) tools, namely the coupling...
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Influence of Toll Collection Method on Motorways on Traffic Safety and Efficiency
PublikacjaThe paper presents the results of the effectiveness analysis for various forms of toll collection on motorway gates and their impact on safety and efficiency of traffic. The results from field tests that were performed on the A1 motorway in Rusocin were used for the analysis. The research included the analysis of the video image of driver behaviour on the way to the toll booths and at toll booths. The PTV VISSIM tool was used to...
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A Framework of A Ship Domain-Based Near-Miss Detection Method Using Mamdani Neuro-Fuzzy Classification
PublikacjaSafety analysis of navigation over a given area may cover application of various risk measures for ship collisions. One of them is percentage of the so called near- miss situations (potential collision situations). In this article a method of automatic detection of such situations based on the data from Automatic Identification System (AIS), is proposed. The method utilizes input parameters such as: collision risk measure based...