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Innovative Research Into Road Restraint Systems
PublikacjaKey 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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Variational Method of Finding Streamlines in Ring Cascades for Creeping Flows
PublikacjaThis paper presents a new, analytical method of finding streamlinesfor creeping flows inside a ring cascade which is composed of an infinite number of infinitely thin blades. An analytical solution has been obtained through minimisation of a dissipation functional by means of variational calculus method. The necessary condition for optimum of a functional gives the Stokes equation if some additional assumptions are introduced....
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Risks to Older People in Road Traffic
Publikacjahe article looks at road traffic risks and main trends from the perspective of older road users (drivers, cyclists, pedestrians). With a longer time to react, poor eyesight and hearing, impaired mobility, ill health and medication, older road users are put at risk. A comprehensive and pro-active strategy is needed to deal with these risk factors and meet the safety and mobility needs...
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Poroelastic Low Noise Road Surfaces
PublikacjaNoise is one of the most important problems related to road traffic. During the last decades, noise emitted by engine and powertrain of vehicles was greatly reduced and tyres became a clearly dominant noise source. The paper describes the concept of low noise poroelastic road surfaces that are composed with mineral and rubber aggregate bound by polyurethane resin. Those surfaces have a porous structure and are much more flexible...
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Taking advantage of symmetries: Gathering of many asynchronous oblivious robots on a ring
PublikacjaOne of the recently considered models of robot-based computing makes use of identical, memoryless mobile units placed in nodes of an anonymous graph. The robots operate in Look-Compute-Move cycles; in one cycle, a robot takes a snapshot of the current configuration (Look), takes a decision whether to stay idle or to move to one of the nodes adjacent to its current position (Compute), and in the latter case makes an instantaneous...
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Tyre/road noise reduction of poroelastic road surface tested in a laboratory
PublikacjaA so-called poroelastic road surface (PERS) is being developed in Europe. This contains a large percentage of rubber particles mixed with hard aggregate (stone and sand) and bound with polyurethane. This gives high air void content (around 30 %), high elasticity and smooth texture, all of which should give low noise properties. Inthis experiment anominally 30 mm thick sample of PERS was mounted on a steel drum. Various car tyres...
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Complexes of silanethiolate ligands: Synthesis, structure, properties and application
PublikacjaThe purposeful syntheses of silanethiolate complexes started approximately in the mid-eighties of the 20th century but no summary of the synthetic efforts has been reported till now. The synthetic methods and the resulting complexes have some common features, which are emphasized throughout the review. Thereby specific difficulties during synthesis are outlined and the structures, properties and possible applications of the resulting...
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The effects of vehicle restraint systems on road safety
PublikacjaKey to understanding the needs and tools of road infrastructure management for preventing run-off-road crashes or minimising their consequences, is to identify the hazads and sources of hazards caused by wrong or improper use of road safety devices and identify errors in the desifn, structure, construction and operation of road safety devices. Studying such an extended scope of the problem required fieldwork and surveys with road...
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An electric ring thruster as auxiliary manoeuvring propulsion system for watercraft - construction analysis
PublikacjaThe reported project aimed at examining properties and purposefulness of use of modern electromagneticbearings for a screw propeller in a prototype version of a synchronous ring motor with rare earths magnets.Bearings of this type generate electromagnetic forces which keep the rotor in a state of levitation. Therotating machine with magnetic bearings can work in any environment which reveals diamagnetic properties(air, vacuum,...
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The Effects of Roadside Hazards on Road Accident Severity
PublikacjaThe 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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Solid road environment and its hazards
PublikacjaAccidents that involve vehicles departing the road tend to have very high severity, as they often result in the vehicle hitting a permanent obstacle (which can be a ree, a pole, facility pillar, front wall of a culvert or a barrier). In recent years, this type of accident caused approx. 19% of all road deaths in Poland. A particularly high risk can be observed on roads located in northern and western...
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Regional implementation of a road safety observatory in Poland
PublikacjaThe paper outlines the background and goals of the Road Safety Observatory in the Polish region of Warmia and Mazury. While created it was Poland’s first road safety Observatory, both at the regional and central level. Established in line with the methodology proposed in the European project SafetyNet, together with the planned National Road Safety Observatory it will form part of a Europe-wide network of observatories linked with...
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Tools for road infrastructure safety management in Poland
PublikacjaThe objective of road safety infrastructure management is to ensure that when roads are planned, designed, built and used road risks can be systematically identified, assessed, removed and mitigated. There are a number of approaches to road safety management. European Union Directive 2008/96/EC requires EU member states to use four basic tools of road safety infrastructure management. An overview of the methods in these countries...
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Road texture influence on tire rolling resistance
PublikacjaTire 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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Assessment of Road Restraint Systems in Polish Conditions
PublikacjaKey to understanding the needs and tools of road infrastructure management is identifying the hazards and their sources involved in having no or faulty road restraint systems. Clarity is also needed on why the systems are wrongly designed, constructed, built and operated. To ensure that the problem is adequately understood, research and site observations were conducted and...
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PERS - QUIET ROAD SURFACE FOR URBAN AREAS
PublikacjaTraffic 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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Ultra Low Noise Poroelastic Road Surfaces
PublikacjaNoise is one of the most important environmental problems related to road traffic. During the last decades, the noise emitted by the engines and powertrains of vehicles was greatly reduced and tires became a clearly dominant noise source. The article describes the concept of low noise poroelastic road surfaces that are composed of mineral and rubber aggregate bound by polyurethane resin. Those surfaces have a porous structure and...
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INFLUENCE OF MEASURING CONDITIONS ON TYRE/ROAD NOISE
PublikacjaA decisive factor for the development of tyres and road surfaces is the ability to conduct representative and reproducible measurements of selected characteristics related to the interaction of tyres and road surfaces. In terms of tyre/road noise measurements in Europe two methods described in ISO/FDIS 11819-2 and ECE Regulation No.117 are used. The latter is compulsory for assigning the tyre noise labels. The methodologies differ...
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ROAD SAFETY FOR CYCLISTS BASED ON THE CALORIES NEEDED
PublikacjaCyclists are a vulnerable group of road users, especially when no separate infrastructure for cyclists is provided. Then, road factors such as distance and altitude differences can indirectly affect cyclists' safety. Therefore, the authors proposed a procedure based on the geometric characteristics of the road that can determine riding difficulties for cyclists. The proposed procedure can be used both by the public authorities who...
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Hierarchical random models in road transport safety
PublikacjaIn this paper multilevel approach to the issue of road safety level on the road network of European regions, classified as NUTS 2 in statistical databases of the EU, has been presented. The risk calculated as the number of death casualties in road accidents per 100,000 inhabitants of a given region has Poisson distribution. Therefore, generalized Poisson model has been assumed in the modelling process. Multilevel stochastic analysis...
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Economical methods for measuring road surface roughness
PublikacjaTwo low-cost methods of estimating the road surface condition are presented in the paper, the first one based on the use of accelerometers and the other on the analysis of images acquired from cameras installed in a vehicle. In the first method, miniature positioning and accelerometer sensors are used for evaluation of the road surface roughness. The device designed for installation in vehicles is composed of a GPS receiver and...
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Evaluation of a sat-type fairness mechanism implemented in a dual-ring network
PublikacjaThe fairness problem was presented. Popular fairness concepts and measures were shown. The RPR fairness mechanism and the SAT mechanism were described. A modification of the SAT algorithm, adapted to the possibilities of Ethernet cards used for implementation of a dual-ring RPR-based network, was proposed. Performance of the proposed modification was measured. Jain's and Chen's fairness indexes were calculated. Effectiveness comparison...
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ROAD SAFETY MANAGEMENT TOOLS FOR COUNTRY STRATEGIC LEVEL
PublikacjaStrategic road safety programmes setting out long-term visions and road infrastructure development plans must be based on road safety forecasts and an understanding of the long-term impact of different measures on road safety. The objective of this paper is to discuss a concept of road safety management for an area of a selected country because there are no simple tools of road safety management for the development and implementation...
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The Reactivity of Phosphanylphosphinidene Complexes of Transition Metals Toward Terminal Dihaloalkanes
PublikacjaThe reactivities of phosphanylphosphinidene complexes [(DippN)2W(Cl)(η2-P−PtBu2)]− (1), [(pTol3P)2Pt(η2- P=PtBu2)] (2), and [(dppe)Pt(η2-P=PtBu2)] (3) toward dihaloalkanes and methyl iodide were investigated. The reactions of the anionic tungsten complex (1) with stochiometric Br(CH2)nBr (n = 3, 4, 6) led to the formation of neutral complexes with a tBu2PP(CH2)3Br ligand or neutral dinuclear complexes with unusual tetradentate...
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The Reactivity of the Imine Bond within Polynuclear Nickel(II) Complexes
PublikacjaThree novel Ni complexes with the Schiff base ligand 2-methoxy-6-(E-2-pyridyliminomethyl)-phenol (L1) are described. In comparison with the similar 2-(pyridine-2-ylimino-methyl)phenol (pymp), the mode of coordination of L1 is altered due to the presence of methoxy substituent introducing the sterical hindrance. During the synthesis of the complexes, partial hydrolysis of the ligand was observed. Since such immediate hydrolysis...
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Road Restraint Systems as a Basis for Roadside Safety Improvement
PublikacjaRoadside-related crashes occur when vehicles run off the road. The majority of the crashes have severe outcomes, especially when an object is hit (tree, pole, supports, front wall of a culvert, barrier). These accidents represent app. 19% of all of Poland's road deaths. Roadside crashes involve: hitting a tree, hitting a barrier, hitting a sign or utility pole, vehicle roll-over on the roadside, vehicle roll-over on a slope and...
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Functionality of road safety devices - identification and analysis of factors
PublikacjaRoad safety devices are designed to protect road users from the risk of injury or death. The principal type of restraint is the safety barrier. Deployed on sites with the highest risk of run-off-road accidents, safety barriers are mostly found on bridges, flyovers, central reservations, and on road edges which have fixed obstacles next to them. If properly designed and installed, safety barriers just as other road safety devices,...
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Low-Temperature Requirements for Bitumen in Central East European Road Construction
PublikacjaThe paper presents the proposition of special assessment of lowtemperature requirements for bitumens in the region of Central and Eastern Europe where there is a moderate transitional area from sea to the continental type of climate. The results of the research program conducted on the road neat bitumens, Styrene-Butadiene-Styrene polymer and polymer-rubber modified bitumen, and multigrade bitumen types were presented and discussed....
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Tools for road infrastructure safety management – Polish experiences
PublikacjaThe objective of road safety infrastructure management is to ensure that when roads are planned, designed, built and used road risks can be systematically identified, assessed, removed and mitigated. There are a number of approaches to road safety management. European Union Directive 2008/96/EC requires EU member states to use four basic tools of road safety infrastructure management. An overview of the methods in these countries...
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Boron Difluoride Complexes of Carbamoyl Meldrum's Acids
Publikacja5-[Hydroxy(aryl/alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-diones react with BF3•Et2O in mild conditions leading to the formation of boron difluoride complexes of carbamoyl Meldrum's acids. The X-ray structure has been obtained for one representative complex. The obtained new compounds are fairly stable at standard ambient conditions and easily isolable.
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Ring thruster with magnetic bearings
Publikacja.
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The influence of road surface unevenness on tyre rolling resistance
PublikacjaThe geometric characteristics of road surface substantially affect the interaction between tyre and road. Depending on pavement texture wavelength, the texture chiefly affects tyre/road friction, rolling resistance, interior and exterior noise, tyre wear, and ride comfort. The article presents results of investigations on the influence of road surface unevenness on the rolling resistance of passenger car and truck tyres. The tests...
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Regional Observatory as a Part of Road Safety Information System
PublikacjaEU experience clearly indicates that it is necessary to inform and motivate the public on road unsafety to undertake specific preventive efforts, as well as making road users feel responsible for the state of road safety and seek to improve this state gradually to protect their health and life. The implementation of the Warmia-Mazury Road Safety Observatory project will not only be an excellent addition to the activities carried...
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Regional observatory as a part of road safety information system
PublikacjaEU experience clearly indicates that it is necessary to inform and motivate the public on road unsafety to undertake specific preventive efforts, as well as making road users feel responsible for the state of road safety and seek to improve this state gradually to protect their health and life. The implementation of the Warmia-Mazury Road Safety Observatory project will not only be an excellent addition to the activities carried...
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Injury Prediction Models for Onshore Road Network Development
PublikacjaIntegrating different modes of transport (road, rail, air and water) is important for port cities. To accommodate this need, new transport hubs must be built such as airports or sea ports. If ports are to grow, they must be accessible, a feature which is best achieved by building new roads, including fast roads. Poland must develop a network of fast roads that will provide good access to ports. What is equally important is to upgrade...
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Analysis of abrasive particle trajectories during single-sided lapping process with driven conditioning ring
PublikacjaIn this paper new kinematics systems were studied for a single lapping process. In order to ensure the constant profile wear of the tool a standard kinematic system can be changed. Lapping is carried out by applying loose abrasive grains between two surfaces and causes a relative motion between them. The result is a finish of multi-directional lay. During process, the mechanism of surface formation are decisively affected by a...
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Biological hazards in low noise, poroelastic road surfaces
PublikacjaDrainage pavements as well as poroelastic pavements ("PERS") are a very efficient way to decrease traffic noise by reducing tire/road noise at the source as well as noise propagation over the road surface. Many noise generating mechanisms at the tire/road interface are very much reduced by road porosity (pipe resonance, "air pumping", Helmholtz resonance and the horn effect). A well-designed porous or poroelastic road surface may...
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The use of GIS tools for road infrastructure safety management
PublikacjaThere are many factors that influence accidents and their severity. They can be grouped within the system of man, vehicle and environment. The article focuses on how GIS tools can be used to manage road infrastructure safety. To ensure a better understanding and identification of road factors, GIS tools help with the acquisition of road parameter data. Their other role is helping with a clear and effective presentation of risk...
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Pedestrian Safety in Road Traffic in Poland
PublikacjaEvery third road accident in Poland involves a pedestrian as a participant or, most of the time, a casualty. Pedestrian accidents are usually the result of complex situations and the outcome of a number of factors related to driver and pedestrian behaviour and road infrastructure. Safety depends largely on how well the traffic condition is perceived and on visibility in traffic. The paper presents the results of analyses of methodologies...
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Modernization of the Trailer for Tyre/Road Rolling Resistance Measurements
PublikacjaIn the article the ways of defining tyre rolling resistance are presented. The advantages of the laboratory tests of tyre/road rolling resistance and the advantages and disadvantages of on the road tyre/road rolling resistance tests are described. The description of the special trailer used for tyre/road rolling resistance measurements designed and constructed in the Faculty of Mechanical Engineering at Gdansk University of Technology,...
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Studying road restraint systems to develop new guidelines
PublikacjaThe paper will present a proposed approach to such work along with preliminary results of numerical studies for selected problems using road safety devices such as safety barriers on horizontal curves, the effect of kerbs on bridges or the location of obstacles within the barrier’s working width. The paper will discuss assumptions to a methodology of numerical models, calculations and automated processing of data to help with assessing...
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Temperature influence on tyre/road noise of selected tyres
PublikacjaAir and road temperatures substantially affect road vehicle noise emission. The temperature influence on tyre/road noise depends mainly on tyre-road combination. It is different for dense and porous pavements, for bituminous and cement ones. It differs also depending on tyres. The correction procedures for temperature effect are still under consideration and preparation. Tyre/road noise measurements using CPX method were performed...
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Photophysics of Untethered ZnTPP-Fullerene Complexes in Solution
PublikacjaThe spectroscopy and dynamic behavior of the self-assembled, Soret-excited zinc tetraphenylporphyrin (ZnTPP) plus fullerene (C60) model system in solution has been examined using steady state fluorescence quenching, nanosecond time-correlated single photon counting, picosecond fluorescence upconversion, and picosecond transient absorption methods. Evidence of ground state complexation is presented. Steady-state quenching of the...
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Effects of Road Infrastructure on Pedestrian Safety
PublikacjaThe objective of the work was to identify risks for pedestrians that involve road infrastructure and roadside and to define how selected elements of geometry and traffic layout affect driver behaviour (speed on approaching pedestrian crossings). The results have helped to formulate recommendations on pedestrian crossing design. The research included an analysis of 2013-2017 statistics to identify the...
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Impact of ITS services on the safety and efficiency of road traffic
PublikacjaThis paper describes the project entitled: “Impact of the use of Intelligent Transport Systems on the level of road safety” (agreement no. DZP/RID-I-41/7/NCBR/2016), implemented as part of the Road Innovations Development (RID) programme, funded by the National Centre for Research and Development and the General Directorate for National Roads and Motorways (GDDKiA). The project is run by a consortium comprising the Motor Transport...
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The guidelines and principles for planning and design of road restraint systems
PublikacjaThe project RID 3A Road Safety Equipment (RoSE) implemented by the Gdansk University of Technology within the RID programme, aims to conduct a comprehensive study and analyses of different vehicle containment systems (PN-EN 1317) and types of support structures (PN-EN 12767) and their performance. Within the project an analysis will be conducted of available research reports...
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Community Road Safety Strategies in the Context of Sustainable Mobility
PublikacjaThe paper presents an overview on the road safety strategies and action plans implemented in the framework of the “SOL - Save our lives: Comprehensive road safety strategy for Central Europe” project. It contains summarization of learned knowledge regarding the efficiency of measures applied and highlights examples of good practices. The purpose of the paper is to provide recommendations for effective and successful planning, formulation...
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Pavement ageing influence on tyre/road noise
PublikacjaRoad surface should be constructed in a way that ensures safe and comfortable traffic conditions, not only when it is newly paved but also during its entire lifetime. An important factor in the asphalt mixture design process is also the expected pavement durability and stability of pavement properties over time. In many countries, road surface starts to play a significant role in traffic noise reduction actions. Selecting a particular...
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Detection of Water on Road Surface with Acoustic Vector Sensor
PublikacjaThis paper presents a new approach to detecting the presence of water on a road surface, employing an acoustic vector sensor. The proposed method is based on sound intensity analysis in the frequency domain. Acoustic events, representing road vehicles, are detected in the sound intensity signals. The direction of the incoming sound is calculated for the individual spectral components of the intensity signal, and the components...
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Modeling of traffic safety indictors on Polish national road network
PublikacjaAlthough decreased from 2001 to 2013, Poland’s road deaths improved at a slower rate than the rest of the EU, leaving Poland as one of the worst road safety performing countries in the EU. The national road network in Poland, despite the dynamic transformation and development, still does not conform to the EU safety standards. Similar situation exists in other EU countries, particularly those in Central and Eastern Europe. Safety...