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Search results for: traffic analysis
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Wireless Link Selection Methods for Maritime Communication Access Networks—A Deep Learning Approach
PublicationIn recent years, we have been witnessing a growing interest in the subject of communication at sea. One of the promising solutions to enable widespread access to data transmission capabilities in coastal waters is the possibility of employing an on-shore wireless access infrastructure. However, such an infrastructure is a heterogeneous one, managed by many independent operators and utilizing a number of different communication...
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ROSANNE Project: New Procedure for Noise Characterisation of Road Surfaces in Europe
PublicationROSANNE is a collaborative project in the 7th EU Framework Programme which aims at harmonising measurement methods for skid resistance, noise emission and rolling resistance of road pavements as a preparation for standardization. The project started in November 2013 and is developing and improving standards in the field of working group CEN/TC 227/WG 5. Regarding the influence of the pavement on the road traffic noise emission,...
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Load capacity and serviceability conditions for footbridges made of fibre-reinforced polymer laminates = Warunki nośności i użytkowalności w odniesieniu do kładek z laminatów polimerowych
PublicationThe contribution is focused on derivation of the Ultimate Limit State (ULS) and Serviceability Limit State (SLS) design criteria for footbridges built of fibre-reinforced polymer matrix (FRP) laminates. The ULS design criterion is based on the design guidelines for above-ground, pressure, FRP composite tanks and the Tsai-Wu failure criterion, which is used to predict the onset of FRP laminates damage. The SLS criterion is based...
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Poroelastic Low Noise Road Surfaces
PublicationNoise 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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Interlaboratory Test to Characterize the Cyclic Behavior of Bituminous Interlayers: An Overview of Testing Equipment and Protocols
PublicationThe performance assessment of multi-layered pavements strongly depends on the mechanical behavior of the interface between bituminous layers. So far, comprehensive studies have been carried out mainly using quasi-static laboratory tests focusing on the interlayer shear strength at failure. However, it is generally recognized that cyclic shear testing will lead to the determination of parameters which are more closely linked to...
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Social media and efficient computer infrastructure in smart city
PublicationSocial media require an efficient infrastructures of computer and communication systems to support a smart city. In a big city, there are several crucial dilemmas with a home and public space planning, a growing population, a global warming, carbon emissions, a lack of key resources like water and energy, and a traffic congestion. In a smart city, we expect an efficient and sustainable transportation, efficient management of resources...
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Further development of the poroelastic road surface within the new Polish project SEPOR
PublicationRoad surfaces have a direct impact on noise generated by rolling tyres, the main and dominant source of noise of moving vehicles. Road surface texture, porosity and stiffness/elasticity govern the pavement contribution to tyre/road noise the most. An experimental PoroElastic Road Surface (PERS) is a wearing course with a high content of interconnected voids (pores) and with an elastic behavior due to the use of small particles...
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Ship domain applied to determining distances for collision avoidance manoeuvres in give-way situations
PublicationShip domain is often used in marine navigation and marine traffic engineering as a safety condition. The basic idea behind those applications is that an encounter of two or more ships can be considered safe if neither of ship domains is intruded by other ships. Research utilising this approach has been documented in numerous works, including publications on optimising collision avoidance manoeuvres performed to fulfil domain-based...
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Car-sharing: The Impact on Metropolitan Spatial Structures
PublicationMany examples from the past show that new technologies designed to solve particular problems can also create side effects generating new problems. Some unforeseen or unwanted results may influence space use and spatial structures. Car-sharing is an invention to compete with car ownership. It drastically rise efficiency of car use, reducing the number of vehicles per users. Diffusion of car-sharing is going to accelerate in the...
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Ultra Low Noise Poroelastic Road Surfaces
PublicationNoise 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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Soiling Effect Mitigation Obtained by Applying Transparent Thin-Films on Solar Panels: Comparison of Different Types of Coatings
PublicationDust accumulation on the front cover of solar panels is closely linked to location and orientation of photovoltaic (PV) installation. Its build-up depends on the module tilt angle, frequency of precipitation, humidity, wind strength and velocity, as well as grain size. Additionally, soil composition is determined by solar farm surroundings such as local factories, agricultural crops, and traffic. Over time, molecules of atmospheric...
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Initial Field Validation of Poroelastic Pavement Made with Crumb Rubber, Mineral Aggregate and Highly Polymer-Modified Bitumen
PublicationTire/road noise in most driving conditions dominates other sources of traffic noise. One of the most efficient ways of reducing tire/road noise is to use the so-called “low noise pavement”. According to numerous studies, at present, poroelastic road pavement that is composed of rubber and mineral aggregate and polyurethane or bituminous binder gives the best noise reduction up to 12 dB. Unfortunately, there are many problems with...
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Optimizing FSO networks resilient to adverse weather conditions by means of enhanced uncertainty sets
PublicationThis work deals with dimensioning of wireless mesh networks (WMN) composed of FSO (free space optics) links. Although FSO links realize broadband transmission at low cost, their drawback is sensitivity to adverse weather conditions causing transmission degradation on multiple links. Hence, designing such FSO networks requires an optimization model to find the cheapest configuration of link capacities that will be able to carry...
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A Method for The Assessing of Reliability Characteristics Relevant to an Assumed Position-Fixing Accuracy in Navigational Positioning Systems
PublicationThis paper presents a method which makes it possible to determine reliability characteristics of navigational positioning systems, relevant to an assumed value of permissible error in position fixing. The method allows to calculate: availability , reliability as well as operation continuity of position fixing system for an assumed, determined on the basis of formal requirements - both worldwide and national, position-fixing accuracy....
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Identification of acoustic event of selected noise sources in a long-term environmental monitoring systems
PublicationABSTRACT Undertaking long-term acoustic measurements on sites located near an airport is related to a problem of large quantities of recorded data, which very often represents information not related to flight operations. In such areas, usually defined as zone of limited use, often other sources of noise exist, such as roads or railway lines treated is such context as acoustic background. Manual verification of such recorded data...
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Biological hazards in low noise, poroelastic road surfaces
PublicationDrainage 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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Urban scene semantic segmentation using the U-Net model
PublicationVision-based semantic segmentation of complex urban street scenes is a very important function during autonomous driving (AD), which will become an important technology in industrialized countries in the near future. Today, advanced driver assistance systems (ADAS) improve traffic safety thanks to the application of solutions that enable detecting objects, recognising road signs, segmenting the road, etc. The basis for these functionalities...
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A risk comparison framework for autonomous ships navigation
PublicationMaritime autonomous surface ships (MASS) may operate in three predefined operational modes (OM): manual, remote, or autonomous control. Determining the appropriate OM for MASS is important for operators and competent authorities that monitor and regulate maritime traffic in given areas. However, a science-based approach to this respect is currently unavailable. To assist the selection of the proper OM, this study presents a risk-based...
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Comparison of pavement noise properties on selected road sections using different CPX measuring systems: self-powered vehicle and special test trailer
PublicationThe recently published ISO standard intended to measure the noise properties of road surfaces in a standardized method (ISO 11819-2:2017) precisely defines measurement procedure of the influence of road surface on traffic noise. According to it, two types of test vehicles may be utilized: a self-powered vehicle fitted with one or more test tyres and a trailer towed by a separate vehicle with one or more test tyres mounted on the...
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Acoustic lifecycle study of the double-layer porous asphalt on E4 in Huskvarna, Sweden
PublicationIn 2010 a double-layer porous asphalt concrete (DPAC) pavement was constructed on the E4 motorway through the Swedish city Huskvarna. Earlier experience in Sweden indicated that it was feasible to obtain a high initial noise reduction but due to the widespread use of studded tires in winter, clogging and ravelling created losses of around 2 dB per year, with an expected acoustical lifetime of only 3 years. However, the improved...
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Enhancing Availability for Critical Services
PublicationTraditional approaches to provide classes of resilient service take the physical network availability as an input and then deploy redundancy and restoration techniques at various layers, often without full knowledge of mappings between layers. This makes it hard (and often inefficient) to ensure the high availability required by critical services which are typically a small fraction of the total traffic. Here, the innovative technique...
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Low noise poroelastic road pavements based on modified asphalt binder
PublicationTire/road noise is one of the most important environmental problems related to road traffic. As the most effective way to fight noise is reduction of sound emission from the source, a lot of work is being done to improve tire and road surfaces construction. This paper describes the first “road” results obtained within the SEPOR project, which is focused on developing a low noise poroelastic road surface based on bituminous binder....
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Optimization of Train Energy Cooperation Using Scheduled Service Time Reserve
PublicationThe main aim of the paper was to develop an innovative approach to the preliminary estimation possibility of train energy cooperation based on data from timetables, without traction calculations. The article points out the need to strive for sustainable and environmentally friendly transport. It was pointed out that rail transport using electric traction is one of the more ecological branches of transport. It also offers a number...
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Hardware-Software Implementation of a Sensor Network for CityTraffic Monitoring Using the FPGA- and ASIC-Based Sensor Nodes
PublicationArtykuł opisuje prototypową sieć sensorową do monitorowania ruchu pojazdów w mieście. Węzły sieci sensorowej, wyposażone w kamerę o niskiej rozdzielczości, obserwują ulice i wykrywają poruszające się obiekty. Detekcja obiektów jest realizowana w oparciu o własny algorytm segmentacji obrazów, wykorzystujący podwójne odejmowanie tła, wykrywanie krawędzi i cieni, działający na dedykowanym systemie mikroelektronicznym typu ''System...
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Asphalt Overlay Enhancement with Fatigue High-Performing Multiaxial Geocomposite
PublicationThe use of gecomposite incorporating multiaxial geogrid and non-woven fabric of high bitumen retention in asphalt overlays results in the increase of life of the designed pavement structure. Such an approach can offer an opportunity to increase the fatigue life (higher traffic capacity) without the need to increase asphalt overlay thickness or to reduce the thickness of asphalt overlay without reduction of pavement life eventually....
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Impact of overloaded vehicles on load equivalency factors and service period of flexible pavements
PublicationOverloaded vehicles occur less frequently in comparison to properly loaded vehicles but due to their greater potential to cause damage they significantly contribute to the distress of pavement structure. As the studies show, the phenomena of vehicles overloading intensifies when the control of traffic is poor and the average percentage of overloaded vehicles on analyzed roads varies from 6% to 23%. The main goal of the ar-ticle...
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Dynamic coloring of graphs
PublicationDynamics is an inherent feature of many real life systems so it is natural to define and investigate the properties of models that reflect their dynamic nature. Dynamic graph colorings can be naturally applied in system modeling, e.g. for scheduling threads of parallel programs, time sharing in wireless networks, session scheduling in high-speed LAN's, channel assignment in WDM optical networks as well as traffic scheduling. In...
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Development of a simulation model of the activities of a transport and forwarding enterprise in the organization of international road cargo transportation
PublicationThe object of this study is the process of planning the work of a transport and forwarding company when serving different categories of customers who need organizational support for the delivery of goods by road transport in international traffic. The solved problem is due to the need to devise recommendations for organizing the work of forwarders when interacting with customers of transport and forwarding services that export...
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Construction of a simulation model of goods delivery in international road transportation taking into account the functioning efficiency of logistics supply chain
PublicationThe object of this study is the process of goods delivery in international road transport using various types of logistics chains. The problem being solved is due to the need to develop recommendations for exporters of goods to reformat or design new supply chains during wartime. The expediency of organizing foreign trade operations by the cargo owners' own forces or with the involvement of enterprises providing logistics consulting...
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CERTIFICATION SYSTEM AS A TOOL FOR IMPROVING THE SAFETY AND SUSTAINABILITY OF SCHOOL-RELATED TRAVELS
PublicationDespite the well-established physical, social, emotional, cognitive, and spatial benefits of active and autonomous school commuting of children and adolescents', many are driven by car. Pilot surveys and field research held in 2019 in 10 Gdansk primary schools confirmed this trend. The article presents a certification system for schools, commissioned by the City of Gdańsk, which is an element of a systemic solution shaping patterns...
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DETERMINATION OF OBJECTIVES FOR URBAN FREIGHT POLICY
PublicationBackground: Decisions regarding strategic planning of urban freight transport very often are based on superficial assumptions inadequately reflecting the actual character of encountered challenges. The trend may be observed to adapt isolated solutions without supporting measures and verification of expected outcomes. Selected urban freight solutions have a significant potential to alleviate transport related problems, but they...
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INFLUENCE OF TEST CONDITIONS ON TYRE/ROAD NOISE MEASURED BY THE DRUM METHOD
PublicationTyre/road noise is one of the most important environmental problems related to road traffic. Nowadays a few standard procedures of tyre/road noise measurements are in use. Unfortunately, measurement conditions specified within relevant standards are very different. For example, procedure described in ISO 11819-2 used for pavement investigations requires tyre load of 3200 N and capped inflation pressure of 200 kPa. At the same time...
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Reduction of exceeding the guaranteed service time for external trucks at the DCT Gdańsk container terminal using a six sigma framework
PublicationPurpose The purpose of this research was to investigate ways to reduce the average amount of exceeded guaranteed service time for external trucks at Deepwater Container Terminal Gdańsk Sp z o.o. (DCT Gdańsk) via dosing the gate activities, in particular IN-Gate entry process of trucks carrying import/export/transit containers. Design/methodology/approach A Six Sigma methodology with the DMAIC methods along with the SIPOC chart,...
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Pedestrian detection in low-resolution thermal images
PublicationOver one million people die in car accidents worldwide each year. A solution that will be able to reduce situations in which pedestrian safety is at risk has been sought for a long time. One of the techniques for detecting pedestrians on the road is the use of artificial intelligence in connection with thermal imaging. The purpose of this work was to design a system to assist the safety of people and car intelligence with the use...
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Social media for e-learning of citizens in smart city
PublicationThe rapid development of social media can be applied for citizens’ e-learning in a smart city. Big cities have to cope with several open issues like a growing population or a traffic congestion. Especially, a home and public space is supposed to be used in more efficient way. Sustainable homes and buildings can be planned with using some modern techniques. Even currently, there is a huge problem with a lack of key resources like...
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The need for linear revitalization. Gdynia case
PublicationThe aim of the article is to discuss the need of defining and implementation of the linear revitalization - the new approach related to the revitalization processes. The results of the preliminary investigations indicate that this kind of revitalization seems to be an important tool supporting city management and planning, especially in cases of cities fragmentation - causing lack of physical, social, economic and ecological cohesion....
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Investigation into MPI All-Reduce Performance in a Distributed Cluster with Consideration of Imbalanced Process Arrival Patterns
PublicationThe paper presents an evaluation of all-reduce collective MPI algorithms for an environment based on a geographically-distributed compute cluster. The testbed was split into two sites: CI TASK in Gdansk University of Technology and ICM in University of Warsaw, located about 300 km from each other, both connected by a fast optical fiber Ethernet-based 100 Gbps network (900 km part of the PIONIER backbone). Each site hosted a set...
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Know your safety indicator – A determination of merchant vessels Bow Crossing Range based on big data analytics
PublicationEven in the era of automatization maritime safety constantly needs improvements. Regardless of the presence of crew members on board, both manned and autonomous ships should follow clear guidelines (no matter as bridge procedures or algorithms). To date, many safety indicators, especially in collision avoidance have been proposed. One of such parameters commonly used in day-to-day navigation but usually omitted by researchers is...
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Simulator for Performance Evaluation of ASON/GMPLS Network
PublicationThe hierarchical control plane network architecture of Automatically Switched Optical Network with utilization of Generalized Multi-Protocol Label Switching protocols is compliant to next generation networks requirements and can supply connections with required quality of service, even with incomplete domain information. Considering connection control, connection management and network management, the controllers of this architecture...
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Calibration of acoustic vector sensor based on MEMS microphones for DOA estimation
PublicationA procedure of calibration of a custom 3D acoustic vector sensor (AVS) for the purpose of direction of arrival (DoA) estimation, is presented and validated in the paper. AVS devices working on a p-p principle may be constructed from standard pressure sensors and a signal processing system. However, in order to ensure accurate DoA estimation, each sensor needs to be calibrated. The proposed algorithm divides the calibration process...
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Study on the prevalence of mobile phone use by car drivers – the case of Poland
Publication: Distracted driving is a significant factor affecting road safety and it can occur as a result of using mobile phones while driving. The aim of the current research is to present the prevalence of mobile phone use by Polish car drivers, based on the roadside and online survey. The field study showed that 11.6% of 1867 drivers were using mobile phones while being in motion and 26.1% of 203 drivers when stopped in front of traffic...
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Magnetic signature reproduction of ferromagnetic ships at arbitrary geographical position, direction and depth using a multi-dipole model
PublicationThe reproduction of magnetic signatures is an important issue concerning the safety of ship traffic, as well as the identification and classification of vessels. Moreover, military applications of magnetic signatures and their reproduction refer to the activation or protection against activation of magnetic naval mines. Previous works on this subject focused on recording and replicating the signatures under the same conditions...
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Interworking and Cross-layer Service Discovery Extensions for IEEEE802.11s Wireless Mesh Standard
PublicationWith the rapid popularization of mobile end-user electronic devices wireless network technologies begin to play a crucial role as networks access technologies. While classic point-to-multipoint wireless access systems, based on fixed infrastructure of base stations providing access to clients, remain the main most popular solution, an increasing attention is devoted to wireless mesh systems, where each connecting client can extend...
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Service and Path Discovery Extensions for Self-forming IEEE 802.11s Wireless Mesh Systems
PublicationWith the rapid growth of the quantity and capabilities of end-user electronic devices, both stationary and mobile, they are employed in increasing number of applications. In this situation, wireless network technologies begin to play a crucial role as networks access technologies, as cable-based solutions tend to be of limited utility in case of easily portable or mobile devices. Resulting development of wireless technologies reached...
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Decreasing CO2 Emissions By Reducing Tire Rolling Resistance
PublicationThe first motor vehicle was built by Nicolas Cugnot almost 250 years ago and since then there has been a continuous process of motor vehicles’ improvements, as well as development of new road pavements. The fuel crisis of the 70s of the 20th century made it clear to vehicle builders that measures should be taken to reduce vehicle fuel consumption and it contributed to an increased interest in electric vehicles. Although significant...
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Surface water quality assessment by the use of combination of multivariate statistical classification and expert information
PublicationThe present study deals with the assessment of surface water quality from an industrial-urban region located in northern Poland near to the city of Gdansk. Concentrations of thirteen chemicals includingtotal polycyclic aromatic hydrocarbons (PAHs), halogenated volatile organic compounds (HVOCs) and major ions in the samples collected at five sampling points during six campaigns were used as variablesthroughout the study. The originality...
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Dew Formation and Chemistry Near a Motorway in Poland
PublicationIn this study, the influence of traffic intensity on dewformation efficiency and chemistry is presented. The measurementswere conducted near the A4 motorway in SW Poland in almost flatland relief with intense agricultural activity. The dew/hoarfrost wascollected by means of insulated plain passive radiative condensersat three sites: AN and AS located in the close vicinity of themotorway (30 m) on the opposite sides of the road,...
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Vehicle detector training with minimal supervision
PublicationRecently many efficient object detectors based on convolutional neural networks (CNN) have been developed and they achieved impressive performance on many computer vision tasks. However, in order to achieve practical results, CNNs require really large annotated datasets for training. While many such databases are available, many of them can only be used for research purposes. Also some problems exist where such datasets are not...
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Modelling of Asphalt Mixes under Long Time Creep at Low Temperatures
PublicationProper description of asphalt mixtures behavior under long time load is one of the most important factors in analyses of strain and stress relations at low temperatures both from traffic and environmental loads. For example different models of thermal stress accumulation require different approaches of description of asphalt concrete. But in all cases it is required to describe its behavior under long time loading, which in some...
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Wpływ barier ochronnych na poziom bezpieczeństwa ruchu drogowego
PublicationWypadki drogowe wciąż stanowią znaczną przyczynę zgonów, dlatego bardzo ważnym jest odpowiednie kształtowanie otoczenia drogi – by mogło ono uzyskać miano „wybaczającego”. Artykuł stanowi wprowadzenie do tematyki drogowych barier ochronnych, i jest częścią pracy dyplomowej realizowanej na Politechnice Gdańskiej, w ramach której autorzy analizują zależności pomiędzy wypadkami a omawianymi urządzeniami BRD. W artykule przedstawiono...