Wyniki wyszukiwania dla: traffic model
-
Comparison of centralized and decentralized preemption in MPLS networks
PublikacjaPreemption is one of the crucial parts of the traffic engineering in MPLS networks. It enables allocation of high-priority paths even if the bandwidth on the preferred route is exhausted. This is achieved by removing previously allocated low-priority traffic, so as enough free bandwidth becomes available. The preemption can be performed either as a centralized or a decentralized process. In this article we discuss the differences...
-
Architecture and Basic Assumptions of RSMAD
PublikacjaThe study presents the architecture of Radio System for Monitoring and Acquisition of Data from Traffic Enforcement Cameras (in short RSMAD) which is used for transmission (realized using GSM, UMTS or TETRA networks, and through the Internet network), archiving and exploring image data of traffic offenses. The paper also presents selected basic assumptions of the RSMAD system, which are relevant to the implemented by the system...
-
Capacity analysis of the selected track system in partially ordered space
PublikacjaA proper location of the interval sections has significant impact on the traffic flow in the railway track network. This issue is critical during line modernization as well as when a new solution accounting for the traffic forecast at particular element of the railway track network is developed . However, the situation is more complex and more expensive for railway stations since improvement of the capacity requires critical organizational...
-
Impact of SDN Controller’s Performance on Quality of Service
PublikacjaSoftware Defined Networking is a paradigm in network architecture; that is quickly becoming commonplace in modern telecommunication systems. It facilitates network customization for the requirements of different applications and simplifies the implementation of new services. Since its proposal, a significant evolution in its functionality has occurred. However, this development brought along problems of efficiency and performance,...
-
Selfish Attacks in Two-Hop IEEE 802.11 Relay Networks: Impact and Countermeasures
PublikacjaIn IEEE 802.11 networks, selfish stations can pursue a better quality of service through selfish MAC-layer attacks. Such attacks are easy to perform, secure routing protocols do not prevent them, and their detection may be complex. Two-hop relay topologies allow a new angle of attack: a selfish relay can tamper with either source traffic, transit traffic, or both. We consider the applicability of selfish attacks and their variants...
-
Does the Use of Cell Phones and Headphones at the Signalised Pedestrian Crossings Increase the Risk of Accident?
PublikacjaReduction of the number of fatalities among pedestrians remains a topical issue in Poland. For many years, this percentage has remained at around 30% of all those who were killed on the road. At the same time, there is an increase in the use of electronic devices by pedestrians and cyclists that may affect their perception when crossing the road. This can lead to traffic accidents. In order to investigate the problem, field studies...
-
Research on Quality Requirements of Data Transmission Services in RSMAD
PublikacjaThe paper presents a results and analysis of research of the quality of service requirements (defined by the QoS attributes) for imaging data transmission services using Radio System for Monitoring and Acquisition of Data from Traffic Enforcement Cameras (in short RSMAD). The paper also presents and discusses results of test on the impact of the size of photos from traffic enforcement cameras on the average transmission time. These...
-
Multipath routing for quality of service differentiation and network capacity optimization in broadband low-earth orbit systems
PublikacjaThis paper shows the importance of employing multiple different paths for routing in Inter-Satellite Link (ISL) networks in broadband Low-Earth Orbit (LEO) satellite systems. A theoretical analysis is presented and a routing concept is proposed to demonstrate three facts that make multipath routing especially important in broadband LEO networks: (1) differences in the propagation delays have a much greater impact on end-to-end...
-
Investigating trip and parking characteristics of hospitals: A case study from Tri-City, Poland
PublikacjaThis 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...
-
Selected Problems of Transport in Port Towns – Tri-City as an Example
PublikacjaPort towns are strategic places from the point of view of transport systems. They form integration junctions for various transport branches , apart from the traditional - road and railway ones , also for water( sea) transport which is active there. Moreover, air transport comes also into consideration , whose efficient functioning must be connected with good accessibility, that concerns sea transport as well. Efficient and...
-
Searching for road deformations using mobile laser scanning
PublikacjaMillions of people use roads every day all over the world. Roads, like many other structures, have an estimated durability. In Poland a lot of the roads were built at the turn of the 20th and 21st c., especially for light cars. Many of these roads carry traffic and heavy goods vehicles which were not predicted when the traffic was first estimated. It creates a lot of problems with technical conditions and the infrastructure must...
-
Study on the accuracy of axle load spectra used for pavement design
PublikacjaWeigh-in-Motion (WIM) systems are used in order to reduce the number of overloaded vehicles. Data collected from WIM provide characteristics of vehicle axle loads that are crucial for pavement design as well as for the development of pavement distress prediction models. The inaccuracy of WIM data lead to erroneous estimation of traffic loads and in consequence inaccurate prediction of pavement distress process. The objective of...
-
Multimedia industrial and medical applications supported by machine learning
PublikacjaThis article outlines a keynote paper presented at the Intelligent DecisionTechnologies conference providing a part of the KES Multi-theme Conference “Smart Digital Futures” organized in Rome on June 14–16, 2023. It briefly discusses projects related to traffic control using developed intelligent traffic signs and diagnosing the health of wind turbine mechanisms and multimodal biometric authentication for banking branches to provide...
-
Urban Railway within the Linear Urban Structure: the Case Study of Perm, Russia
PublikacjaThe paper analyses the ten years’ experience of Perm to develop its system of the urban train trying to reveal the reasons for its modest performance and decline in the passenger traffic. The authors show how the Urban Train fits within the city urban structure and eval uate the potential of the Urban Train to become a feasible solution to the problem of connecting the periphery with the city centre. Furthermore,...
-
Assessing Highway Travel Time Reliability using Probe Vehicle Data
PublikacjaProbe vehicle data (also known as “floating car data”) can be used to analyze travel time reliability of an existing road corridor in order to determine where, when, and how often traffic congestion occurs at particular road segments. The aim of the study is to find the best reliability performance measures for assessing congestion frequency and severity based on probe data. Pilot surveys conducted on A2 motorway in Poland confirm...
-
Theory and implementation of a virtualisation level Future Internet defence in depth architecture
PublikacjaAn EU Future Internet Engineering project currently underway in Poland defines three parallel internets (PIs). The emerging IIP system (IIPS, abbreviating the project’s Polish name), has a four-level architecture, with level 2 responsible for creation of virtual resources of the PIs. This paper proposes a three-tier security architecture to address level 2 threats of unauthorised traffic injection and IIPS traffic manipulation...
-
Mobile indicators in GIS and GPS positioning accuracy in cities
PublikacjaThe publication describes the possible use of tele-geoprocessing as a synergy of modern IT solutions, telecommunications and GIS algorithms. The paper presents a possibility of urban traffic monitoring with the use of mobile GIS indicators of dedicated monitoring system designed for taxi corporation. The system is based on a stationary and mobile software package. The optimal and minimal assumptions for the monitoring of urban...
-
Study of QoS Parameters Measurement Methodology and Requirements in RSMAD
PublikacjaThe paper presents the results of analysis and research of the quality of service requirements (defined by the QoS parameters) for data transmission services in Radio System for Monitoring and Acquisition of Data from Traffic Enforcement Cameras (in short: RSMAD). The paper also presents and discusses the results of test of impact of the size of images from traffic enforcement cameras (TECs) on the average transmission time. Moreover,...
-
Pedestrian and bicycle bridges as examples of safe collision-free road crossings
PublikacjaPedestrians are most at risk when they are crossing the road. This represents a significant proportion of all fatalities among pedestrians, amounting respectively to 50% in non-built-up areas and 75% in built-up areas. The most frequent reason for this accident is failure to give way. What is most terrible is that 30% of pedestrian accidents occurred at marked pedestrian crossings. Therefore, an important part of pedestrian safety...
-
Design of Resilient Vehicle-to-Infrastructure Systems
PublikacjaVehicular ad hoc networks (VANETs) have recently gained noticeable attention due to advantages in improving road traffic safety, shaping the road traffic and providing infotainment opportunities to travellers. However, transmission characteristics following from the IEEE 802.11p standard and the high mobility of VANET nodes remarkably reduce the lifetime, reach and capacity of wireless links, and often lead to simultaneous disruptions...
-
Preliminary safety assessment of Polish interchanges
PublikacjaInterchanges are a key and the most complex element of a road infrastructure. The safety and functionality of interchanges determine the traffic conditions and safety of the entire road network. This applies particularly to motorways and express-ways, for which they are the only way to access and exchange traffic. A big problem in Poland is the lack of comprehensive tools for designers at individual stages of the design process....
-
Analysis of positioning methods using Global Navigation Satellite Systems (GNSS) in Polish State Railways (PKP)
PublikacjaEach year, global navigation satellite systems (GNSS) improve their accuracy, availability, continuity, integrity, and reliability. Due to these continual improvements, the systems are increasingly used in various modes of transport, including rail transport, the subject of this publication. GNSS are used for rail passenger information, rail traffic management, and rail traffic control. These applications differ in the positioning...
-
Evaluating the convenience and safety effects of bicycle lanes in Gdańsk
PublikacjaBicycle lanes are lanes marked on a road and dedicated for exclusive use for cyclists.. Because they combine bike and motor traffic they provide directness and flow. However, a shared use of streets could result in bicycle-car accidents. Following up on the good practice Western countries have in planning cycle infrastructure, Gdańsk has recently introduced bike lanes on a few streets. The aim of the research was to assess the...
-
Disappearing Bridge
PublikacjaThe main parts of the Hafen City’s residential development are still under construction. Close by, uninviting offi ce buildings defi ne Hammerbrook. Neighboring Rothenburgsort is inhabited by many citizens but lacks cultural attractions. Street traffic and water barriers distinctly separate the districts.
-
Protection in elastic optical networks
PublikacjaIn this article, we analyze gains resulting from the use of EON architectures with special focus on transportation of cloud-ready and content-oriented traffic in the context of network resilience. EONs are a promising approach for future optical transport networks and, apart from improving the network spectral efficiency, bring such new capabilities as squeezed protection, which reduces resource requirements in failure scenarios....
-
Universities as Part of the Urban Transport System—Analysis Using the Example of the Gdansk University of Technology and Medical University of Gdansk
PublikacjaMany cities perceive academic function as a distinctive feature, representing the rank and prestige of the city. Universities provide places for work and learning for a high number of people and represent a significant proportion compared to the total city population (even 22%). Many of Polish universities are located in the urban structure in the form of spatially concentrated campuses, where the number of people working and studying...
-
Acoustic evaluation of road surfaces using different Close Proximity testing devices
PublikacjaAccording 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....
-
A novel approach exploiting properties of convolutional neural networks for vessel movement anomaly detection and classification
PublikacjaThe article concerns the automation of vessel movement anomaly detection for maritime and coastal traffic safety services. Deep Learning techniques, specifically Convolutional Neural Networks (CNNs), were used to solve this problem. Three variants of the datasets, containing samples of vessel traffic routes in relation to the prohibited area in the form of a grayscale image, were generated. 1458 convolutional neural networks with...
-
Determination of equivalent axle load factors with the use of strain energy of distortion
PublikacjaThe paper proposes a new method for calculation of equivalent axle load factors based on the analysis of strain energy of distortion induced in road pavements by traffic loads. The main advantage of the method is the more accurate calculation of the effects of multiple axles and super single versus dual tyres. The methodconsiders the location of critical points, at which strain energy of distortion reaches extreme values. When...
-
Excavation induced cast iron pipeline failure – a numerical study
PublikacjaNumerical study on impact of an unsecured excavation on an underground pipeline. Analysis focused on investigation of pipeline displacement generated by soil movement caused by excavation and heavy traffic. Numerical calculations and soil parameter sensitivity analysis based on Finite Element Method. Some comparisons of results with real-life failure cases.
-
Study of Multi-Class Classification Algorithms’ Performance on Highly Imbalanced Network Intrusion Datasets
PublikacjaThis paper is devoted to the problem of class imbalance in machine learning, focusing on the intrusion detection of rare classes in computer networks. The problem of class imbalance occurs when one class heavily outnumbers examples from the other classes. In this paper, we are particularly interested in classifiers, as pattern recognition and anomaly detection could be solved as a classification problem. As still a major part of...
-
Technical diagnostics and monitoring of traction current collectors
PublikacjaNew evaluation methods of the technical condition of rolling stock current collectors are proposed in this paper. The method of automatic measurement of the pantograph static force characteristic, realized when the vehicle runs through the test section of the track with especially prepared overhead line height distribution, has been practically implemented by the Polish Railways. The method of testing the slipper spring suspension...
-
Vehicle detector training with labels derived from background subtraction algorithms in video surveillance
PublikacjaVehicle detection in video from a miniature station- ary closed-circuit television (CCTV) camera is discussed in the paper. The camera provides one of components of the intelligent road sign developed in the project concerning the traffic control with the use of autonomous devices being developed. Modern Convolutional Neural Network (CNN) based detectors need big data input, usually demanding their manual labeling. In the presented...
-
CFFT columns in road through railroad crossings
PublikacjaThere were 12801 road through railroad one-level crossings in Poland in 2018. 215 accidents happened at them in 2018. In order to increase safety in rail and road traffic two-level crossings should be used. They are definitely safer and make the traffic more smooth. In the design and construction of two-level intersections of railway and road or path columns of circular cross-section are often used. They can be successfully replaced...
-
Acoustic Detector of Road Vehicles Based on Sound Intensity
PublikacjaA method of detecting and counting road vehicles using an acoustic sensor placed by the road is presented. The sensor measures sound intensity in two directions: parallel and perpendicular to the road. The sound intensity analysis performs acoustic event detection. A normalized position of the sound source is tracked and used to determine if the detected event is related to a moving vehicle and to establish the direction of movement....
-
Vehicular Communication Environments
PublikacjaCommunication to and between road vehicles (cars, truck, buses, trains, etc.) are of growing interest. This is partly due to the attractive services that cooperative intelligent transport systems (C-ITSs) provides, mainly in the areas of traffic safety and traffic efficiency. An enabler for C-ITS is wireless vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication, collectively referred to as vehicle-to-X (V2X)...
-
Modulo N Backoff Scheme for effective QoS differentiation and increased bandwidth utilization in IEEE 802.11 networks
PublikacjaThe paper presents a new "modulo N" channel access scheme for wireless Local Area Networks (WLANs). The novel solution derives from the Distributed Coordination Function (DCF) of the IEEE 802.11 standard, further elaborated as Enhanced Distribution Channel Access (EDCA) by the 802.11e draft specification. The main innovation concerns improvement of the binary exponential backoff scheme used for collision avoidance in 802.11 networks....
-
TEST FOR ASSESSING THE ENERGY EFFICIENCY OF VEHICLES WITH INTERNAL COMBUSTION ENGINES
PublikacjaThe 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...
-
COMPARISON OF NOISE EMISSION OF HCT AND CLASSIC VEHICLE COMBINATIONS FOR TIMBER TRANSPORTATION IN SWEDEN
PublikacjaBy means of a special simulation tool, the noise emission of a high-capacity heavy vehicle (11 axles) was compared to that of a classic heavy vehicle (a truck-dolly-semitrailer with 8 axles). The two cases are designated “Extended vehicle” versus “Classic vehicle” in this study, having total lengths of 34 and 25 m, respectively. The Classic vehicle represents the most common articulated heavy vehicle configuration for transport...
-
Mobile monitoring system for gaseous air pollution
PublikacjaThe concept of a mobile monitoring system for chemical agents control in the air is presented. The proposed system can be applied to measure industrial and car traffic air pollution. A monitoring station is relatively small and can be placed on cars or public transportation vehicles. Measured concentrations of air pollutants are collected and transferred via the GSM network to a central data base. Exemplary results from a measurement...
-
Polish- Russian Cooperation of Pomorskie Province
PublikacjaPolish-Russian Cooperation of Pomorskie Province commenced in 1999 and was based on the intergovernmental agreements. The new agreement, executed between the authorities of the Pomeranian Province and Kaliningrad Oblast in 2002, provided for cooperation in many areas. The contacts between the partners were dominated by economic cooperation. The Polish-Russian cooperation stopped with Polish accession to the Schengen zone. Cooperation...
-
Naprawa przegubów Estakady Kwiatkowskiego w Gdyni = Hinges repair og the E. Kwiatkowskiego trestle bridge in Gdynia
PublikacjaE. Kwiatkowskiego trestle bridge is one of the main parts of road infrastructure that connects sea transport (container terminal BTC) national roads A1,1,7. Every limitation of motor traffic causes many problems for Gdynia inhabitants and moreover economical loss in transport economy. In recent two years there were expertise and repair project of hinges carried out. Paper presents genesis and reasons of hinges damages, theoretical...
-
Module of priorities for public transport vehicles in the TRISTAR system
PublikacjaOne of the most important elements of the intelligent traffic control systems is the ability to control movement in such a way as to privilege the selected users movement, in particular public transport vehicles. Implemented at the Tri-City the TRISTAR system will also have a module for prioritizing public transport vehicles. The article presents a characteristics of the priority action system: the way of communication with the...
-
Composite sandwich footbridge - measured dynamic response vs. FEA
PublikacjaThe paper describes a process of in situ dynamic tests of a composite sandwich footbridge before its accepta-tion for exploitation in real traffic conditions. It is only a part of a big research task that includes design, manufacture and introduce practical application of the bridge. The in situ measured natural modes and fre-quencies are compared with numerically determined ones. Finite element analysis is established to estimate...
-
Use of numerical methods in the analysis of traction energy systems—an overview of the practical examples
PublikacjaA characteristic feature of trolleybus transport is the random nature of traffic caused by congestion. It predestinates statistical and numerical methods for the analysis of trolleybus energy system. There are presented 3 methods of trolleybus traction system analysis: simulation of supply system based on Monte Carlo method, analysis of energy recovery potential based on statistical data analysis and benchmark of trolleybus supply...
-
Diagnosis of damages in family buildings using neural networks
PublikacjaThe article concerns a problem of damages in family buildings, which result from traffic-induced vibrations. These vibrations arise from various causes and their size is influenced by many factors. The most important is the type of a road, type and weight of vehicles that run on the road, type and condition of the road surface, the distance from the house to the source of vibrations and many others which should be taken into account....
-
Quality Expectations of Mobile Subscribers
PublikacjaMobile systems, by nature, have finite resources. Radio spectrum is limited, expensive and shared between many users and services. Mobile broadband networks must support multiple applications of voice, video and data on a single IP-based infrastructure. These converged services each have unique traffic holding and quality requirements. A positive user experience must be obtained through efficient partitioning of the available wireless...
-
LOW NOISE TIRES FOR HYBRID AND ELECTRIC VEHICLES
PublikacjaLow Emission Vehicles that are hybrid and electric cars may benefit from specially designed tires that are optimized for driving conditions typical for such vehicles. It is possible that in the future Low Emission Vehicles, especially passenger cars, will substitute conventional vehicles in all applications, however for the time being they are mostly used in urban and suburban areas. Urban traffic has a rather low demand for grip...
-
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...
-
Cycling as a Sustainable Transport Alternative in Polish Cittaslow Towns
PublikacjaIt is well known that growing motor traffic in urban areas causes air pollution and noise which affects the environment and public health. It is hardly surprising then that cycling should be used as an alternative mode of transport, not just in major cities but also in smaller ones including those that are members of the Cittaslow network. Their approach is based on sustainable development, care for the environment and transport...