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Machine learning applied to acoustic-based road traffic monitoring
PublicationThe motivation behind this study lies in adapting acoustic noise monitoring systems for road traffic monitoring for driver’s safety. Such a system should recognize a vehicle type and weather-related pavement conditions based on the audio level measurement. The study presents the effectiveness of the selected machine learning algorithms in acoustic-based road traffic monitoring. Bases of the operation of the acoustic road traffic...
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Selected elements of the methodology and method of designing amphibious flood rescue vehicles
PublicationThe methodology of designing amphibious flood rescue vehicles at the preliminary stage of the design process has been presented. The study has been focused on the properties of such vehicles when afloat, with their on-land behaviour and performance characteristics having been left aside. In the study, a general assumption has been made that the amphibious flood rescue vehicles should be designed as, above all, watercraft that additionally...
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Estimation of Average Speed of Road Vehicles by Sound Intensity Analysis
PublicationConstant monitoring of road traffic is important part of modern smart city systems. The proposed method estimates average speed of road vehicles in the observation period, using a passive acoustic vector sensor. Speed estimation based on sound intensity analysis is a novel approach to the described problem. Sound intensity in two orthogonal axes is measured with a sensor placed alongside the road. Position of the apparent sound...
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The Impact of Weather on Traffic Speed in Urban Area
PublicationThe issue of the impact of weather conditions on trip speed of vehicles has been studied for a long time and it is still the subject of many scientific researches. The impact of atmospheric conditions on the speed with which drivers drive their vehicles seems to be obvious. Good weather conditions, sunny weather with good visibility surely provokes higher speed while rainfall, wind...
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Shore Construction Detection by Automotive Radar for the Needs of Autonomous Surface Vehicle Navigation
PublicationAutonomous surface vehicles (ASVs) are becoming more and more popular for performing hydrographic and navigational tasks. One of the key aspects of autonomous navigation is the need to avoid collisions with other objects, including shore structures. During a mission, an ASV should be able to automatically detect obstacles and perform suitable maneuvers. This situation also arises in near-coastal areas, where shore structures like...
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JOURNAL OF MOLECULAR MODELING
Journals -
Safety assurance strategies for autonomous vehicles
PublicationAssuring safety of autonomous vehicles requires that the vehicle control system can perceive the situation in the environment and react to actions of other entities. One approach to vehicle safety assurance is based on the assumption that hazardous sequences of events should be identified during hazard analysis and then some means of hazard avoidance and mitigation, like barriers, should be designed and implemented. Another approach...
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Dynamic Analysis of the Turnout Diverging Track for HSR with Variable Curvature Sections
PublicationThe paper presents an analytical method of identifying the curvature of the turnout diverging track consisting of sections of varying curvature. Both linear and nonlinear (polynomial) curvatures of the turnout diverging track are identified and evaluated in the paper. The presented method is a universal one, it enables to assume curvature values at the beginning and end point of the geometrical layout of the turnout. The results...
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The Effects of Roadside Hazards on Road Accident Severity
PublicationThe risk of becoming involved in an accident emerges when elements of the transport system do not operate properly (man – vehicle – road – roadside). The road, its traffic layout andsafety equipment have a critical impact on road user safety. This gives infrastructural work a priority in road safety strategies and programmes. Run-off-road accidents continue to be one of the biggest problems of road safety with consequences including...
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Designing of Parking Spaces on Parking Taking into Account the Parameters of Design Vehicles
PublicationNowadays, in all cities, there is an acute problem of a lack of parking spaces. The number of vehicles is constantly increasing not only in big cities and megacities, but also in small towns of the country, and there are not enough parking places—the pace of solving the problem is several times slower than the growth rate of transport among citizens. The paper is dedicated to the determination of an optimal size of a parking place...
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Symulacja hałasu emitowanego przez przejeżdżający pojazd
PublicationPrzedstawiono program komputerowy Vehicle Noise Simulation umożliwiający przeprowadzenie symulacji hałasu przejeżdżającego pojazdu w oparciu o charakterystyki kierunkowe dźwięku emitowanego przez poszczególne źródła hałasu w pojeździe takie jak: opony, silnik, układ wydechowy.
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Visual measurement system for chosen parameters of current collectors
PublicationA current collector is an element in a traction vehicle, used for movable, contact con-nection between the main circuit of this vehicle and the contact line. Bad technical condi-tion of these important elements in the main circuit of the vehicle result in its incorrect cooperation with contact line. Periodic control of technical condition of current collectors ensures infallible current collection. The pantograph diagnostics consists...
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Development of a new generation of unmanned surface and underwater vehicles using the advanced technologies and achievements towards the application of control systems by the artificial intelligence AI.
PublicationThe operation of offshore structures at sea requires implementation of the advanced systems of permanent monitoring of work of such the installations. Novel solutions concerning such the systems should be associated with application of unmanned maritime surface and underwater platforms. The unmanned maritime platforms are and will be based on application of the newest achievements of some important technologies. Between these technologies...
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Innovative Research Into Road Restraint Systems
PublicationKey to understanding the needs and building road infrastructure management tools to prevent and mitigate run-off-road accidents is to identify hazards and their sources which are a result of wrong design, construction, installation and maintenance of road restraint systems [1]. Building such tools requires advanced studies with field tests, simulations and models to demonstrate the effects of selected parameters on road user safety...
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Analysis of catalitic reactors usefulness to reduce pollution generated by piston combustion engines with regard to ship main engines
PublicationThe article presents results which indicate that the use of catalytic reactors to reduce emissions of harmful compunds contained in the exhaust gas is important in the operation of vehicle motors operation. Efforts of the shipbuilding industry to reduce the toxicity of exhaust gas emitted by the main engines have been indicated and pointed to the desirability of the use of these catalysts in maritime transport. It has been pointed...
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Improving Social Justice, Environmental Integrity, and Geopolitical Resilience in EU Electric Mobility Transition
PublicationWe recommend improving social justice, environmental integrity, and geopolitical resilience in electric mobility transition. To achieve this policy recommendation, we propose the following: (1) Increase societal acceptance and justice of climate policies by engaging local stakeholders; (2) Prioritize sustainable mobility practices over replacement of internal combustion engine vehicle (ICEV) with battery electric vehicle (BEV);...
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Acoustic evaluation of road surfaces using different Close Proximity testing devices
PublicationAccording to the valid standard, Close Proximity (CPX) method intends to evaluate the influence of road surfaces on traffic noise. Measurements may be carried out with the use of a self-powered vehicle or a special test trailer equipped with testing tyre towed by another vehicle. Two different testing devices took part in the research organized in Poland in order to determine the ranking of road surfaces in terms of acoustic parameters....
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Estimating Traffic Intensity Employing Passive Acoustic Radar and Enhanced Microwave Doppler Radar Sensor
PublicationInnovative road signs that can autonomously display the speed limit in cases where the trac situation requires it are under development. The autonomous road sign contains many types of sensors, of which the subject of interest in this article is the Doppler sensor that we have improved and the constructed and calibrated acoustic probe. An algorithm for performing vehicle detection and tracking, as well as vehicle speed measurement,...
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Sounding rocket vibration mechanical filter and amplifier
PublicationMeasuring accelerations and vibrations of a sounding rocket provides both information for engineers on the launcher vehicle performance as well as environment description for future payload designers. Typically, information on the level of vibration and eigenfrequencies are required to properly design a payload. This paper presents a design of a novel mechanical filter and amplifier for mechanical vibrations. Its key feature is...
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The application of microscopic models in the study of pedestrian traffic
PublicationCities (especially in Central and Eastern Europe) focus on improving the road network, which aims to improve the efficiency of motor traffic and minimize congestion. Most of existing tools for analysing the effectiveness of urban transport networks do not assume to analyse the impact of walking and cycling on efficiency of transport systems. It is therefore necessary to develop solutions...
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Counting and tracking vehicles using acoustic vector sensors
PublicationA method is presented for counting vehicles and for determining their movement direction by means of acoustic vector sensor application. The assumptions of the method employing spatial distribution of sound intensity determined with the help of an integrated 3D intensity probe are discussed. The intensity probe developed by the authors was used for the experiments. The mode of operation of the algorithm is presented in conjunction...
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Magnetic signatures of land vehicles
PublicationThe results of numerical simulations of the magnetic field surrounding of land vehicles' models have been presented in this paper. Vehicle containing of ferromagnetic elements distorts the Earth's magnetic field. This distortion can be measured by magnetometers. It is possible to detect and identify an object on the basis of its magnetic signature.
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An Overview of Bidirectional EV Chargers: Empowering Traction Grid-Powered Chargers
PublicationIn recent years, the number of electric vehicles has been at least doubling year after year. As a result, today electric vehicles already account for approximately 10% of the global automotive market, which positively affects environment in urbanized areas. However, to take full advantage of the EV integration it is necessary to use renewable sources for their charging; optimally place charging stations/terminals; optimally manage...
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Metamodel-based optimization of a high-tension cable barrier in crash tests with a large SUV
PublicationRoad safety barriers play an important role in improving road safety. Cable barriers are one of the types of road barriers. Cable barriers have favorable collision-related properties, especially in terms of the safety of the vehicle occupants. Despite the continuous development of road barrier systems, the current European standard EN1317, which is used to evaluate the performance of road barriers, does not take into account all...
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Determination of Vehicles Load Equivalency Factors for Polish Catalogue of Typical Flexible and Semi-rigid Pavement Structures
PublicationThe new Polish Catalog of Typical Flexible and Semi-rigid Pavement Structures was introduced to use in practice in 2014. Much of works were focused on actualization of vehicles load equivalency factors. For this purpose data delivered from weigh-inmotion were analyzed. Four methods of determination of load equivalency factors for pavement structure design were compared. The analysis showed that fourth power equation, AASHTO 1993...
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Potential for ITS/ICT Solutions in Urban Freight Management
PublicationThe article presents a study on applying ITS solutions in planning and management of urban freight transport in Gdynia. The traffic management system Tristar which is under implementation and its related systems show a potential to assist in development of freight transport measures. Recommendations for urban freight policy development supplementing Gdynia's Sustainable Urban Mobility Plan were used as a basis for identification...
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Investigating trip and parking characteristics of hospitals: A case study from Tri-City, Poland
PublicationThis research aims to investigate public hospitals’ trip and parking characteristics based on the study conducted in Poland in September 2021 on the example of the Tri-City agglomeration. The main objective of the research was to build models of the relationship between the number of trips during peak transport hours and the number of beds. The second research element was the analysis of transport behavior in these areas. The research...
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A study of nighttime vehicle detection algorithms
Open Research DataThis dataset is from my master's thesis "A study of nighttime vehicle detection algorithms". It contains both raw data and preprocessed dataset ready to use. In the pictures below you can see how images were annotated.
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Assessing the Effects of the Road Surface and Weather Conditions on Road Safety
PublicationWhen transport is analysed for its safe delivery the focus is mainly on assessing the safety of roads and the risk of undesired events. These include road accidents, an occurrence which is relatively rare and random. Randomness means that accidents depend on several factors which are partly deterministic (can be controlled) and partly stochastic (random and unpredictable). The set of crash contributing factors can be classified...
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Practical Eco-Driving Strategy for Suburban Electric Multiple Unit
PublicationIn this paper, a practical approach to velocity profile optimization for electric multiple unit was presented. The study focuses on a case of fast urban railway, which is a popular mean of transport across Tricity, Poland. Based on observations and measurements, a potential for improvement of energy efficiency by modifying the speed profile was recognized. In order to conduct necessary calculations, simulation model of railway...
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Fuctional structure of diagnostic system for wheeled tractors
PublicationAn application of computer controlled fuel injection systems in vehicle engines and growing demands concerning toxic substances emission and fuel consumption was a main reason for OBD (On Board Diagnosis) development. In spite of a great technological development, only some tractors are equipped in diagnostic systems. On board diagnosis is strongly connected with emission demands and does not concern other important vehicle functions.In...
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An application of simulation model of fuel consumption in diagnostic system of wheeled tractors
PublicationAn application of computer controlled fuel injection systems in vehicle engines and growing demands concerning toxic substances emission and fuel consumption was a main reason for OBD (On Board Diagnosis) development. In spite of a great technological development, only some tractors are equipped in diagnostic systems. On board diagnostic is strongly connected with emission demands and does not concern other important vehicle functions. In...
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Mobile virtual presence in civil engineering education and training
PublicationEducation technologies are on the cusp, emerging technologies connected with each other might reveal new added value in this field. In this paper, the author showed a framework for conducting civil engineering classes with a virtual presence on the construction site. The presented idea might be realized by use of the unnamed aerial vehicle equipped with 360 video camera. On-site activities are transmitted at a distance by GSM and...
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The newly developed multipurpose ROV or an integrated mine hunting system
PublicationA modular mine hunting ROV concept is presented. The design is based on experience gained during 15 years of exploitation of the Ukwial ROV and development of Gluptak single shot mine hunting systems. The design goal was to multiply capabilities of the Ukwial without increasing weight and dimensional envelope. The vehicle is composed around powerful propulsion system that gives the system basic PVDS capability and mine disposal...
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Road texture influence on tire rolling resistance
PublicationTire rolling resistance is one of the most important resistive forces acting on road vehicles. It depends on tire and surface characteristics as well as vehicle operating parameters. This paper deals with the influence of road surface texture on rolling resistance of passenger car tires. Results of road measurements performed on variety of road surfaces are presented.
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Effect of the Road Environment on Road Safety in Poland
PublicationRun-off-road accidents tend to be very severe because when a vehicle leaves the road, it will often crash into a solid obstacle (tree, pole, supports, front wall of a culvert, barrier). A statistical analysis of the data shows that Poland's main roadside hazard is trees and the severity of vehicles striking a tree in a run-off-road crash. The risks are particularly high in north-west Poland with many of the roads lined up with...
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Dynamic GNSS Mission Planning Using DTM for Precise Navigation of Autonomous Vehicles
PublicationNowadays, the most widely used method for estimating location of autonomous vehicles in real time is the use of Global Navigation Satellite Systems (GNSS). However, positioning in urban environments using GNSS is hampered by poor satellite geometry due to signal obstruction created by both man-made and natural features of the urban environment. The presence of obstacles is the reason for the decreased number of observed satellites...
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Pedestrian Safety at Midblock Crossings on Dual Carriageway Roads in Polish Cities
PublicationRoad 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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Introductory modeling for decision-making using AMPL
e-Learning CoursesIntroductory modeling for decision-making using AMPL
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Modeling projects for decision-making using AMPL
e-Learning CoursesModeling projects for decision-making using AMPL
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Road texture influence on tyre rolling resistance
PublicationTyre performance, one of the critical factors for vehicle users, is strongly related to theroad surface characteristics, most notably to the pavement texture. Phenomena that occur at the tyre/road interface affect tyre friction (skid resistance), rolling resistance, tyre wear and tyre/road noise. This article deals with relationship between surface texture and rolling resistance of light and heavy vehicle tyres. Mean profile depth...
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Travel Time of Public Transport Vehicles Estimation
PublicationEffective prediction of speed is central to advanced traveler information and transportation management systems. The speed of public transport vehicles is affected by many external factors including traffic volume, organization and infrastructure. The literature presents methods for estimating travel time on sections of a transport network and vehicle arrival at stops, often making use of the AVL (automatic vehicle location). The...
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Evaluation of Street Lighting Efficiency Using a Mobile Measurement System
PublicationThe issue concerns the initial stage of work on a method for performing a rapid assessment of the energy efficiency and illuminance of a street lighting installation. The proposed method is based on simultaneous measurement of illuminance from three lux meters placed on the roof of the vehicle. The data are acquired in road traffic, while the vehicle is driving. The proposed solution will allow in the future to quickly and reproducibly...
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At what temperature should the tire rolling resistance be measured?
PublicationThe climate crisis is already an indisputable fact and therefore, it is necessary to reduce energy consumption, and especially energy wasting. One of the ways to reduce energy consumption of motor vehicles is to decrease vehicle movement resistance, including rolling resistance. In order for the optimization of tire rolling resistance to be efficient, it is necessary to apply appropriate optimization criteria that are closely related...
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TEST FOR ASSESSING THE ENERGY EFFICIENCY OF VEHICLES WITH INTERNAL COMBUSTION ENGINES
PublicationThe most popular method for assessing the energy efficiency of vehicles is to compare the fuel consumption achieved in the conditions of selected approval test. Operating conditions are defined using the speed profiles, usually for only two categories: urban and extra-urban driving. Assessing the energy efficiency of vehicles should be performed using a more detailed classification of conditions. Presented results of comparison...
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Numerical Modeling of Hydrosystems 2024/2025
e-Learning CoursesKurs do przedmiotu NUMERICAL MODELING OF HYDROSYSTEMS Specjalność: Environmental Engineering (WILiŚ), II stopnia, stacjonarne dr hab. inż. Michał Szydłowski, prof. PG
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Numerical Modeling of Hydrosystems 2024/2025
e-Learning CoursesKurs do przedmiotu NUMERICAL MODELING OF HYDROSYSTEMS Specjalność: Environmental Engineering (WILiŚ), II stopnia, stacjonarne dr hab. inż. Michał Szydłowski, prof. PG
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Numerical Modeling of Hydrosystems 2023/2024
e-Learning CoursesKurs do przedmiotu NUMERICAL MODELING OF HYDROSYSTEMS Specjalność: Environmental Engineering (WILiŚ), II stopnia, stacjonarne dr hab. inż. Michał Szydłowski, prof. PG
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ON ESTIMATION OF OCCUPANT SAFETY IN VEHICULAR CRASHES INTO ROADSIDE OBSTACLES USING NON-LINEAR DYNAMIC ANALYSIS
PublicationThe article describes a comparison of two general methods of occupants safety estimation based on a numerical examples. The so-called direct method is mainly based on the Head Injury Criterion of a crash test dummy in a vehicle with passive safety system while the indirect method uses a European standards approach to estimate impact severity level. Numerical simulations in LS-DYNA have been conducted.
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Novel proposal for V2X systems and WBAN cooperation to improve road safety
PublicationIn this paper, a novel proposal of the automotive Vehicle-to-Everything system solution is presented. In this proposal, there are included the Machine to Machine type communication system and the sensor system based on a short-range the Wireless Body Area Network communication. The aim of this paper is the analysis of the model for communication, especially its architecture and signals structure for the proposed solution. The use...