Units of measurement in transportation

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The units of measurement in transportation describes the unit of measurement used to express various transportation quantities, as used in statistics, planning, and their related applications.

Contents

Transportation quantity

The currently popular units are:

Length of journey

Traffic flow

Passenger

Payload quantity

Passenger-distance

Passenger-distance is the distance (km or miles) travelled by passengers on transit vehicles; determined by multiplying the number of unlinked passenger trips by the average length of their trips.

Passengers per hour per direction

Passengers per hour per direction (pphpd) measures the maximum route capacity of a transport system.

Passengers per bus hour

A system may carry a high number of passengers per distance (km or mile) but a relatively low number of passengers per bus hour if vehicles operate in congested areas and thus travel at slower speed.

Passengers per bus distance

A transit system serving a community with a widely dispersed population must operate circuitous routes that tend to carry fewer passengers per distance (km or mile). A higher number is more favorable.

Freight

Freight is measured in mass-distance. A simple unit of freight is the kilogram-kilometre (kgkm), the service of moving one kilogram of payload a distance of one kilometre.

Payload quantity

1 t = (1/0.907) short tons = 1.102 short tons.

Payload-distance

Usage

The metric units (pkm and tkm) are used internationally. (In aviation where United States customary units are widely used, the International Air Transport Association (IATA) releases its statistics in the metric units.)

In the US, sometimes United States customary units are used.

Derivation

The dimension of the measure is the product of the payload mass and the distance transported.

Example

A semi truck traveling from Los Angeles to Chicago (approximate distance 2,015 miles) carrying 14 short tons of cargo delivers a service of 14 * 2,015 = 28,210 ton-miles of freight (equal to about 41,187 tkm).

Intermodal containers

Intermodal container traffic is commonly measured in twenty-foot equivalent units (TEUs), rather than cargo weight, e.g. a TEU-km would be the equivalent of one twenty-foot container transported one kilometer. [6]

Transportation density

Transportation density can be defined as the payload per period, say passenger / day or tonne / day. This can be used as the measure of intensity of the transportation on a particular section or point of transportation infrastructure, say road or railway. This can be used in comparison with the construction, running costs of the infrastructure.

Fatalities by VMT

Fatalities by VMT (vehicle miles traveled) is a unit for assessing road traffic fatalities. This metric is computed by dividing the fatalities by the estimated VMT.

Usually, transport risk is computed by reference to the distance traveled by people, while for road traffic risk, only vehicle traveled distance is usually taken into account. [7]

In the United States, the unit is used as an aggregate in yearly federal publications, while its usage is more sporadic in other countries. For instance, it appears to compare different kind of roads in some publications as it had been computed on a five-year period between 1995 and 2000. [8]

In the United States, it is computed per 100 million miles traveled, while internationally it is computed in 100 million or 1 billion kilometers traveled.

According to the Minnesota Department of Public Safety, Office of Traffic Safety

Volume of traffic, or vehicle miles traveled (VMT), is a predictor of crash incidence. All other things being equal, as VMT increases, so will traffic crashes. The relationship may not be simple, however; after a point, increasing congestion leads to reduced speeds, hanging the proportion of crashes that occur at different severity levels. [9]

Energy efficiency

Energy efficiency in transport can be measured in L/100 km or miles per gallon (mpg). This can be normalized per vehicle, as in fuel economy in automobiles, or per seat, as for example in fuel economy in aircraft.

History

MacNeal 1994 [10] discusses the history of this topic, exploring such units and how humans developed the current state of logically recognizing and naming them.

See also

Related Research Articles

<span class="mw-page-title-main">Transportation in Canada</span>

Canada, the world's second-largest country in total area, is dedicated to having an efficient, high-capacity multimodal transportation spanning often vast distances between natural resource extraction sites, agricultural and urban areas. Canada's transportation system includes more than 1,400,000 kilometres (870,000 mi) of roads, 10 major international airports, 300 smaller airports, 72,093 km (44,797 mi) of functioning railway track, and more than 300 commercial ports and harbours that provide access to the Pacific, Atlantic and Arctic oceans as well as the Great Lakes and the St. Lawrence Seaway. In 2005, the transportation sector made up 4.2% of Canada's GDP, compared to 3.7% for Canada's mining and oil and gas extraction industries.

<span class="mw-page-title-main">Transport in the Netherlands</span>

The Netherlands is both a very densely populated and a highly developed country in which transport is a key factor of the economy. Correspondingly it has a very dense and modern infrastructure, facilitating transport with road, rail, air and water networks. In its Global Competitiveness Report for 2014-2015, the World Economic Forum ranked the Dutch transport infrastructure fourth in the world.

<span class="mw-page-title-main">Ton</span> Unit of mass or volume with different values

Ton is any of several units of measure of mass, volume or force. It has a long history and has acquired several meanings and uses.

<span class="mw-page-title-main">Mont Blanc Tunnel</span> Highway tunnel underneath the Alps connecting France and Italy

The Mont Blanc Tunnel is a highway tunnel between France and Italy, under Mont Blanc in the Alps. It links Chamonix, Haute-Savoie, France with Courmayeur, Aosta Valley, Italy, via the French Route Nationale 205 and the Italian Traforo T1, in particular the motorways serving Geneva and Turin. The passageway is one of the major trans-Alpine transport routes, particularly for Italy, which relies on this tunnel for transporting as much as one-third of its freight to northern Europe. It reduces the route from France to Turin by 50 kilometres and to Milan by 100 km (60 mi). Northeast of Mont Blanc's summit, the tunnel is about 15 km (10 mi) southwest of the tripoint with Switzerland, near Mont Dolent.

<span class="mw-page-title-main">Fuel efficiency</span> Form of thermal efficiency

Fuel efficiency is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical potential energy contained in a carrier (fuel) into kinetic energy or work. Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum of variance is often illustrated as a continuous energy profile. Non-transportation applications, such as industry, benefit from increased fuel efficiency, especially fossil fuel power plants or industries dealing with combustion, such as ammonia production during the Haber process.

<span class="mw-page-title-main">Road traffic safety</span> Methods and measures for reducing the risk of death and injury on roads

Road traffic safety refers to the methods and measures used to prevent road users from being killed or seriously injured. Typical road users include pedestrians, cyclists, motorists, vehicle passengers, and passengers of on-road public transport.

<span class="mw-page-title-main">Twenty-foot equivalent unit</span> Unit of cargo capacity

The twenty-foot equivalent unit is a general unit of cargo capacity, often used for container ships and container ports. It is based on the volume of a 20-foot-long (6.1 m) intermodal container, a standard-sized metal box that can be easily transferred between different modes of transportation, such as ships, trains, and trucks.

<span class="mw-page-title-main">Commercial driver's license</span> License to operate large or heavy vehicles

A commercial driver's license (CDL) is a driver's license required in the United States to operate large and heavy vehicles or a vehicle of any size that transports hazardous materials or more than 15 passengers.

<span class="mw-page-title-main">Rail freight transport</span> Practice of transporting cargo by rail

Rail freight transport is the use of railways and trains to transport cargo as opposed to human passengers.

Annual average daily traffic, abbreviated AADT, is a measure used primarily in transportation planning, transportation engineering and retail location selection. Traditionally, it is the total volume of vehicle traffic of a highway or road for a year divided by 365 days. AADT is a simple, but useful, measurement of how busy the road is.

<span class="mw-page-title-main">Fuel economy in automobiles</span> Distance traveled by a vehicle compared to volume of fuel consumed

The fuel economy of an automobile relates to the distance traveled by a vehicle and the amount of fuel consumed. Consumption can be expressed in terms of the volume of fuel to travel a distance, or the distance traveled per unit volume of fuel consumed. Since fuel consumption of vehicles is a significant factor in air pollution, and since the importation of motor fuel can be a large part of a nation's foreign trade, many countries impose requirements for fuel economy.

<span class="mw-page-title-main">Passenger</span> Person who travels in a vehicle

A passenger is a person who travels in a vehicle, but does not bear any responsibility for the tasks required for that vehicle to arrive at its destination or otherwise operate the vehicle, and is not a steward. The vehicles may be bicycles, buses, cars, passenger trains, airliners, ships, ferryboats, and other methods of transportation.

<span class="mw-page-title-main">Transportation safety in the United States</span> Overview of transportation safety

Transportation safety in the United States encompasses safety of transportation in the United States, including automobile crashes, airplane crashes, rail crashes, and other mass transit incidents, although the most fatalities are generated by road incidents annually killing 32,479 people in 2011 to over 42,000 people in 2022. The number of deaths per passenger-mile on commercial airlines in the United States between 2000 and 2010 was about 0.2 deaths per 10 billion passenger-miles. For driving, the rate was 150 per 10 billion vehicle-miles: 750 times higher per mile than for flying in a commercial airplane. For a person who drives a million miles in a lifetime this amounts to a 1.5% chance of death.

The energy efficiency in transport is the useful travelled distance, of passengers, goods or any type of load; divided by the total energy put into the transport propulsion means. The energy input might be rendered in several different types depending on the type of propulsion, and normally such energy is presented in liquid fuels, electrical energy or food energy. The energy efficiency is also occasionally known as energy intensity. The inverse of the energy efficiency in transport is the energy consumption in transport.

Passengers per hour per direction (p/h/d), passengers per hour in peak direction (pphpd) or corridor capacity is a measure of the route capacity of a rapid transit or public transport system.

A vehicle miles traveled tax, also frequently referred to as a VMT tax, VMT fee, mileage-based fee, or road user charge, is a policy of charging motorists based on how many miles they have traveled.

<span class="mw-page-title-main">Epidemiology of motor vehicle collisions</span>

Worldwide, it was estimated that 1.25 million people were killed and many millions more were injured in motor vehicle collisions in 2013. This makes motor vehicle collisions the leading cause of death among young adults of 15–29 years of age and the ninth most frequent cause of death for all ages worldwide. In the United States, 40,100 people died and 2.8 million were injured in crashes in 2017, and around 2,000 children under 16 years old die every year.

<span class="mw-page-title-main">Public transport</span> Shared transportation service for use by the general public

Public transport is a system of transport for passengers by group travel systems available for use by the general public unlike private transport, typically managed on a schedule, operated on established routes, and that may charge a posted fee for each trip. There is no rigid definition of which kinds of transport are included, and air travel is often not thought of when discussing public transport—dictionaries use wording like "buses, trains, etc." Examples of public transport include city buses, trolleybuses, trams and passenger trains, rapid transit and ferries. Public transport between cities is dominated by airlines, coaches, and intercity rail. High-speed rail networks are being developed in many parts of the world.

<span class="mw-page-title-main">Peak car</span> Decline of private vehicle use

Peak car is a hypothesis that motor vehicle distance traveled per capita, predominantly by private car, has peaked and will now fall in a sustained manner. The theory was developed as an alternative to the prevailing market saturation model, which suggested that car use would saturate and then remain reasonably constant, or to GDP-based theories which predict that traffic will increase again as the economy improves, linking recent traffic reductions to the Great Recession of 2008.

References

  1. 1 2 Dunkerley, Fay; Rohr, Charlene; Daly, Andrew (2014). Road traffic demand elasticities A rapid evidence assessment (PDF) (Report). Santa Monica, Calif.: RAND Corporation.
  2. "vehicle-km". Environmental Terminology Discovery Service. European Environment Agency. Retrieved 2008-10-06.
  3. Werlin, Josef (1999). "Wörterbuch der Abkürzungen, Neu bearbeitete und erweiterte Auflage". Mannheim, Leipzig, Wien, Zürich: Dudenverlag.[ permanent dead link ]
  4. "Abkürzungen und Akronym Datenbank". abkuerzungen.woxikon.de (in German). Woxikon. Retrieved 2024-07-28.
  5. "Main Terms Used in Civil Aviation Statistics" (docx).
  6. Directorate, OECD Statistics. "OECD Glossary of Statistical Terms – TEU-kilometre Definition". stats.oecd.org.
  7. "La sécurité routière en France" [Road safety in France](PDF). www.ladocumentationfrancaise.fr (in French). Archived from the original (PDF) on 2018-06-26.
  8. "Sécurité des routes express" [Expressway safety](PDF). dtrf.setra.fr (in French).
  9. "Minnesota Motor Vehicle Crash Facts, 2014" (PDF). Department of Public Safety, Office of Traffic Safety.
  10. MacNeal, Edward (1994). Mathsemantics: Making Numbers Talk Sense. Penguin. ISBN   9780140234862.