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Boris Kerner
Boris S. Kerner (born 1947) is a German physicist and civil engineer who created three phase traffic theory. ttp://www.aps.org/publications/apsnews/200404/upload/apr04.pdf Article by Davis in "APS News" titled "Physicists and traffic flow"/ref> The three phase traffic theory is the framework for the description of empirical vehicular traffic states in three traffic phases: (i) free traffic flow (F), (ii) synchronized traffic flow (S), and (iii) wide moving jam (J). The synchronized traffic flow and wide moving jam phases belong to congested traffic. Biography Kerner is an engineer and physicist. He was born in Moscow, Soviet Union in 1947 and graduated from the Moscow Technical University MIREA in 1972. Boris Kerner was received Ph.D. and Sc.D. (Doctor of Sciences) degrees in the Academy of Sciences of the Soviet Union, respectively, in 1979 and 1986. Between 1972 and 1992, his major interests include the physics of semiconductors, plasma and solid state physics. During t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moscow Technological University (MIREA)
Moscow ( , US chiefly ; rus, links=no, Москва, r=Moskva, p=mɐskˈva, a=Москва.ogg) is the capital and largest city of Russia. The city stands on the Moskva River in Central Russia, with a population estimated at 13.0 million residents within the city limits, over 17 million residents in the urban area, and over 21.5 million residents in the metropolitan area. The city covers an area of , while the urban area covers , and the metropolitan area covers over . Moscow is among the world's largest cities; being the most populous city entirely in Europe, the largest urban and metropolitan area in Europe, and the largest city by land area on the European continent. First documented in 1147, Moscow grew to become a prosperous and powerful city that served as the capital of the Grand Duchy that bears its name. When the Grand Duchy of Moscow evolved into the Tsardom of Russia, Moscow remained the political and economic center for most of the Tsardom's history. When the Ts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematical Modeling
A mathematical model is a description of a system using mathematical concepts and language. The process of developing a mathematical model is termed mathematical modeling. Mathematical models are used in the natural sciences (such as physics, biology, earth science, chemistry) and engineering disciplines (such as computer science, electrical engineering), as well as in non-physical systems such as the social sciences (such as economics, psychology, sociology, political science). The use of mathematical models to solve problems in business or military operations is a large part of the field of operations research. Mathematical models are also used in music, linguistics, and philosophy (for example, intensively in analytic philosophy). A model may help to explain a system and to study the effects of different components, and to make predictions about behavior. Elements of a mathematical model Mathematical models can take many forms, including dynamical systems, statistical m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reconstruction With Kerner's Three-phase Theory
Reconstruction may refer to: Politics, history, and sociology *Reconstruction (law), the transfer of a company's (or several companies') business to a new company *''Perestroika'' (Russian for "reconstruction"), a late 20th century Soviet Union political movement *Critical reconstruction, an architectural theory related to the reconstruction of Berlin after the end of the Berlin Wall *Economic reconstruction *Ministry of Reconstruction, a UK government department *The Reconstruction era of the United States, the period after the Civil War, 1865–1877 ** The Reconstruction Acts, or Military Reconstruction Acts, addressing requirements for Southern States to be readmitted to the Union *Reconstruction Finance Corporation, a United States government agency from 1932–1957 Arts, entertainment, and media Films * ''Reconstruction'' (1968 film), a Romanian tragicomedy * ''Reconstruction'' (2001 film), about the 1959 Ioanid Gang bank heist in Romania * ''Reconstruction'' (2003 film), a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three-phase Traffic Theory
Three-phase traffic theory is a theory of traffic flow developed by Boris Kerner between 1996 and 2002. It focuses mainly on the explanation of the physics of traffic breakdown and resulting congested traffic on highways. Kerner describes three phases of traffic, while the classical theories based on the fundamental diagram of traffic flow have two phases: ''free flow'' and ''congested traffic''. Kerner’s theory divides congested traffic into two distinct phases, ''synchronized flow'' and ''wide moving jam'', bringing the total number of phases to three: # Free flow (''F'') # Synchronized flow (''S'') # Wide moving jam (''J'') The word "wide" is used even though it is the length of the traffic jam that is being referred to. A phase is defined as a ''state in space and time.'' Free flow (''F'') In free traffic flow, empirical data show a positive correlation between the flow rate q (in vehicles per unit time) and vehicle density k (in vehicles per unit distance). This relatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Headway
Headway is the distance or duration between vehicles in a transit system measured in space or time. The ''minimum headway'' is the shortest such distance or time achievable by a system without a reduction in the speed of vehicles. The precise definition varies depending on the application, but it is most commonly measured as the distance from the tip (front end) of one vehicle to the tip of the next one behind it. It can be expressed as the distance between vehicles, or as time it will take for the trailing vehicle to cover that distance. A "shorter" headway signifies closer spacing between the vehicles. Airplanes operate with headways measured in hours or days, freight train Rail freight transport is the use of railroads and trains to transport cargo as opposed to human passengers. A freight train, cargo train, or goods train is a group of freight cars (US) or goods wagons (International Union of Railways) haul ...s and commuter rail systems might have headways measured in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speed Limit
Speed limits on road traffic, as used in most countries, set the legal maximum speed at which vehicles may travel on a given stretch of road. Speed limits are generally indicated on a traffic sign reflecting the maximum permitted speed - expressed as kilometres per hour (km/h) and/or miles per hour (mph). Speed limits are commonly set by the legislative bodies of national or provincial governments and enforced by national or regional police and judicial authorities. Speed limits may also be variable, or in some places nonexistent, such as on most of the Autobahnen in Germany. The first numeric speed limit for automobiles was the limit introduced in the United Kingdom in 1861. the highest posted speed limit in the world is , applied on two motorways in the UAE. Speed limits and safety distance are poorly enforced in the UAE, specifically on the Abu Dhabi to Dubai motorway - which results in dangerous traffic, according to a French-government travel-advisory. Additionally, "dr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transportation Engineering
Transportation engineering or transport engineering is the application of technology and scientific principles to the planning, functional design, operation and management of facilities for any mode of transportation in order to provide for the safe, efficient, rapid, comfortable, convenient, economical, and environmentally compatible movement of people and goods transport. The planning aspects of transportation engineering relate to elements of urban planning, and involve technical forecasting decisions and political factors. Technical forecasting of passenger travel usually involves an urban transportation planning model, requiring the estimation of trip generation (number of purposeful trips), trip distribution (destination choice, where the traveler is going), mode choice (mode that is being taken), and route assignment (the streets or routes that are being used). More sophisticated forecasting can include other aspects of traveler decisions, including auto ownership, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saturation (traffic)
In traffic engineering, saturation describes the maximum traffic flow which can be handled by a junction. The saturation flow is the rate at which a continuous flow of vehicles can pass through a constant green signal, typically expressed in vehicles per hour or PCUs per hour. A formula to calculate saturation flows based on lane geometry is given in Transport and Road Research Laboratory RR67. However, the formula can over-estimate saturation flows at congested locations. Degree of Saturation The degree of saturation (DoS) of an intersection (typically under traffic signal control) or a link measures the demand relative to the total capacity. A DoS value of 100% meaning that demand and capacity are equal and no further traffic is able to progress through the junction. The formula to calculate DoS is: *Degree of saturation = (demand x cycle time) / (saturation flow x effective green time) Values over 85%-90% typically indicate traffic congestion Traffic congestion is a con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic Light
Traffic lights, traffic signals, or stoplights – known also as robots in South Africa are signalling devices positioned at intersection (road), road intersections, pedestrian crossings, and other locations in order to control flows of traffic. Traffic lights consist normally of three signals, transmitting meaningful information to drivers and riders through colours and symbols including arrows and bicycles. The regular traffic light colours are red, yellow, and green arranged vertically or horizontally in that order. Although this is internationally standardised,1968, as revised 1995 and 2006Vienna Convention on Road Signs and Signals United Nations Publication ECE/TRANS/196. ISBN 978-92-1-116973-7. URL Accessed: 7 January 2022. variations exist on national and local scales as to traffic light sequences and laws. The method was first introduced in December 1868 on Parliament Square in London to reduce the need for police officers to control traffic. Since then, electricity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-driving Car
A self-driving car, also known as an autonomous car, driver-less car, or robotic car (robo-car), is a car that is capable of traveling without human input.Xie, S.; Hu, J.; Bhowmick, P.; Ding, Z.; Arvin, F.,Distributed Motion Planning for Safe Autonomous Vehicle Overtaking via Artificial Potential Field IEEE Transactions on Intelligent Transportation Systems, 2022. Self-driving cars use sensors to perceive their surroundings, such as optical and thermographic cameras, radar, lidar, ultrasound/sonar, GPS, odometry and inertial measurement units. Control systems interpret sensory information to create a three-dimensional model of the surroundings. Based on the model, the car identifies appropriate navigation paths, and strategies for managing traffic controls (stop signs, etc.) and obstacles.Hu, J.; Bhowmick, P.; Jang, I.; Arvin, F.; Lanzon, A.,A Decentralized Cluster Formation Containment Framework for Multirobot Systems IEEE Transactions on Robotics, 2021. Once the technol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vehicular Ad-hoc Network
Vehicular ad hoc networks (VANETs) are created by applying the principles of mobile ad hoc networks (MANETs) – the spontaneous creation of a wireless network of mobile devices – to the domain of vehicles. VANETs were first mentioned and introduced in 2001 under " car-to-car ad-hoc mobile communication and networking" applications, where networks can be formed and information can be relayed among cars. It was shown that vehicle-to-vehicle and vehicle-to-roadside communications architectures will co-exist in VANETs to provide road safety, navigation, and other roadside services. VANETs are a key part of the intelligent transportation systems (ITS) framework. Sometimes, VANETs are referred as Intelligent Transportation Networks. They are understood as having evolved into a broader "Internet of vehicles". which itself is expected to ultimately evolve into an "Internet of autonomous vehicles". While, in the early 2000s, VANETs were seen as a mere one-to-one application of MANET p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
