|
Traffic Congestion Reconstruction With Kerner's Three-phase Theory
Vehicular traffic can be either free or congested. Traffic occurs in time and space, i.e., it is a spatiotemporal process. However, usually traffic can be measured only at some road locations (for example, via road detectors, video cameras, Floating car data, probe vehicle data, or Floating car data, phone data). For efficient Road transport#Traffic control, traffic control and other intelligent transportation systems, the reconstruction of traffic congestion is necessary at all other road locations at which traffic measurements are not available. Traffic congestion can be reconstructed in space and time (Fig. 1) based on Boris Kerner’s three phase traffic theory, three-phase traffic theory with the use of the ASDA and FOTO models introduced by Kerner.[http://www.freepatentsonline.com/6813555.pdf Boris S. Kerner; Method for monitoring the condition of traffic for a traffic network comprising effective narrow points, Deutsche Patentoffenlegung DE19944075A1; USA patent: US 6813555B1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic
Traffic comprises pedestrians, vehicles, ridden or herded animals, trains, and other conveyances that use public ways (roads) for travel and transportation. Traffic laws govern and regulate traffic, while rules of the road include traffic laws and informal rules that may have developed over time to facilitate the orderly and timely flow of traffic. Organized traffic generally has well-established priorities, lanes, right-of-way, and traffic control at intersections. Traffic is formally organized in many jurisdictions, with marked lanes, junctions, intersections, interchanges, traffic signals, or signs. Traffic is often classified by type: heavy motor vehicle (e.g., car, truck), other vehicle (e.g., moped, bicycle), and pedestrian. Different classes may share speed limits and easement, or may be segregated. Some jurisdictions may have very detailed and complex rules of the road while others rely more on drivers' common sense and willingness to cooperate. Organi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asda En 3 Asda Model
Asda Stores Ltd. () (often styled as ASDA) is a British supermarket chain. It is headquartered in Leeds, England. The company was founded in 1949 when the Asquith family merged their retail business with the Associated Dairies company of Yorkshire. It expanded into Southern England during the 1970s and 1980s, and acquired Allied Carpets, 61 large Gateway Supermarkets and other businesses, such as MFI Group. It sold these acquisitions during the 1990s to concentrate on the supermarkets. It was listed on the London Stock Exchange until 1999 when it was acquired by Walmart for £6.7 billion. Asda was the second-largest supermarket chain in the United Kingdom between 2003 and 2014 by market share, at which point it fell into third place. Besides its core supermarkets, the company also offers assistance for insurance and payment services and a mobile phone provider. In February 2021, the Issa brothers (Mohsin and Zuber) and TDR Capital acquired Asda. Walmart retains "an equit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic Flow
In mathematics and transportation engineering, traffic flow is the study of interactions between travellers (including pedestrians, cyclists, drivers, and their vehicles) and infrastructure (including highways, signage, and traffic control devices), with the aim of understanding and developing an optimal transport network with efficient movement of traffic and minimal traffic congestion problems. History Attempts to produce a mathematical theory of traffic flow date back to the 1920s, when Frank Knight first produced an analysis of traffic equilibrium, which was refined into Wardrop's first and second principles of equilibrium in 1952. Nonetheless, even with the advent of significant computer processing power, to date there has been no satisfactory general theory that can be consistently applied to real flow conditions. Current traffic models use a mixture of empirical and theoretical techniques. These models are then developed into traffic forecasts, and take account of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traffic Bottleneck
A traffic bottleneck is a localized disruption of vehicular traffic on a street, road, or highway. As opposed to a traffic jam, a bottleneck is a result of a specific physical condition, often the design of the road, badly timed traffic lights, or sharp curves. They can also be caused by temporary situations, such as vehicular accidents. Bottlenecks can also occur in other methods of transportation. Capacity bottlenecks are the most vulnerable points in a network and are very often the subject of offensive or defensive military actions. Capacity bottlenecks of strategic importance - such as the Panama Canal where traffic is limited by the infrastructure - are normally referred to as choke points; capacity bottlenecks of tactical value are referred to as mobility corridors. Causes Traffic bottlenecks are caused by a wide variety of things: * Construction zones where one or more existing lanes become unavailable (as depicted in the diagram on the right) * Accident sites that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microscopic Traffic Flow Model
Microscopic traffic flow models are a class of scientific models of vehicular traffic dynamics. In contrast, to macroscopic models, microscopic traffic flow models simulate single vehicle-driver units, so the dynamic variables of the models represent microscopic properties like the position and velocity of single vehicles. Car-following models Also known as ''time-continuous models'', all car-following models have in common that they are defined by ordinary differential equations describing the complete dynamics of the vehicles' positions x_\alpha and velocities v_\alpha. It is assumed that the input stimuli of the drivers are restricted to their own velocity v_\alpha, the net distance (bumper-to-bumper distance) s_\alpha = x_ - x_\alpha - \ell_ to the leading vehicle \alpha-1 (where \ell_ denotes the vehicle length), and the velocity v_ of the leading vehicle. The equation of motion of each vehicle is characterized by an acceleration function that depends on those input stimuli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kerner's Breakdown Minimization Principle
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 thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fundamental Diagram
The fundamental diagram of traffic flow is a diagram that gives a relation between road traffic flux (vehicles/hour) and the traffic density (vehicles/km). A macroscopic traffic model involving traffic flux, traffic density and velocity forms the basis of the fundamental diagram. It can be used to predict the capability of a road system, or its behaviour when applying inflow regulation or speed limits. Basic statements * There is a connection between traffic density and vehicle velocity: The more vehicles are on a road, the slower their velocity will be. * To prevent congestion and to keep traffic flow stable, the number of vehicles entering the control zone has to be smaller or equal to the number of vehicles leaving the zone in the same time. * At a critical traffic density and a corresponding critical velocity the state of flow will change from stable to unstable. * If one of the vehicles brakes in unstable flow regime the flow will collapse. The primary tool for graphically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Traffic Management
Active traffic management (also managed lanes, smart lanes, managed/smart motorways) is a method of increasing peak capacity and smoothing traffic flows on busy major highways. Techniques include variable speed limits, hard-shoulder running and ramp-metering controlled by overhead variable message signs. It has been implemented in several countries, including Germany, the United Kingdom and the United States. United Kingdom It is currently in operation on the M42 motorway south-east of Birmingham and in Warwickshire. The scheme had initially been criticised by some due to possible safety and environmental concerns, however a Highways Agency report into the first six months of the scheme showed a reduction in the number of accidents from over 5 a month to 1.5 per month on average. it has now been expanded onto other roads following the initial evaluation on the M42. It is seen as a less expensive alternative to road widening. Technology The section of road subject to ATM is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asda En 5 Traveltime
Asda Stores Ltd. () (often styled as ASDA) is a British supermarket chain. It is headquartered in Leeds, England. The company was founded in 1949 when the Asquith family merged their retail business with the Associated Dairies company of Yorkshire. It expanded into Southern England during the 1970s and 1980s, and acquired Allied Carpets, 61 large Gateway Supermarkets and other businesses, such as MFI Group. It sold these acquisitions during the 1990s to concentrate on the supermarkets. It was listed on the London Stock Exchange until 1999 when it was acquired by Walmart for £6.7 billion. Asda was the second-largest supermarket chain in the United Kingdom between 2003 and 2014 by market share, at which point it fell into third place. Besides its core supermarkets, the company also offers assistance for insurance and payment services and a mobile phone provider. In February 2021, the Issa brothers (Mohsin and Zuber) and TDR Capital acquired Asda. Walmart retains "an equit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Data System
Radio Data System (RDS) is a communications protocol standard for embedding small amounts of digital information in conventional FM radio broadcasts. RDS standardizes several types of information transmitted, including time, station identification and program information. The standard began as a project of the European Broadcasting Union (EBU), but has since become an international standard of the International Electrotechnical Commission (IEC). Radio Broadcast Data System (RBDS) is the official name used for the U.S. version of RDS. The two standards are only slightly different, with receivers able to work with either system and only minor inconsistencies in the displayed data. Both versions carry data at 1,187.5 bits per second on a 57 kHz subcarrier, so there are exactly 48 cycles of subcarrier during every data bit. The RBDS/RDS subcarrier was set to the third harmonic of the 19 kHz FM stereo pilot tone to minimize interference and intermodulation between t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Westdeutscher Rundfunk
Westdeutscher Rundfunk Köln (''West German Broadcasting Cologne''; WDR, ) is a German public-broadcasting institution based in the Federal State of North Rhine-Westphalia with its main office in Cologne. WDR is a constituent member of the consortium of German public-broadcasting institutions, ARD. As well as contributing to the output of the national television channel '' Das Erste'', WDR produces the regional television service WDR Fernsehen (formerly known as WDF and West3) and six regional radio networks. History Origins The Westdeutsche Funkstunde AG (WEFAG) was established on 15 September 1924. There was a substantial purge of left wing staff following the Nazi seizure of power in 1933. This included Ernst Hardt, Hans Stein and Walter Stern. WDR was created in 1955, when Nordwestdeutscher Rundfunk (NWDR) was split into Norddeutscher Rundfunk (NDR) – covering Lower Saxony, Schleswig-Holstein, and Hamburg – and Westdeutscher Rundfunk, responsible for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_003.JPG "Click for more on -> Asda En 3 Asda Model")
