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109-515: The system is labelled as "autonomous" in English, however, the models in operation are optically guided and feature a driver on board. Despite "rail" in the name, the system does not use rails. Automated Rapid Transit systems (ARTs) can operate independently without the need for a guiding sensor and as a result, they fall under the classification of buses. Consequently, vehicles deployed on these routes are mandated to display license plates . Before

218-415: A low-floor design from a space frame with bolted-on panels to support the weight of passengers. It is built as a bi-directional vehicle , with driver's cabs at either end, allowing it to travel in either direction at full speed. The 6.5 km (4.0 miles) long ART lane was built through downtown Zhuzhou and inaugurated in 2018. The ART is equipped with various optical and other types of sensors to allow

327-516: A number plate ( British , Indian and Australian English ) or license plate ( American English ) or licence plate ( Canadian English ), is a metal or plastic plate attached to a motor vehicle or trailer for official identification purposes. All countries require registration plates for commercial road vehicles such as cars, trucks, and motorcycles, for hire. Whether they are required for other vehicles, such as bicycles, boats, or tractors, may vary by jurisdiction. The registration identifier

436-430: A rail ). For railroads, this is called curve resistance but for roads it has (at least once) been called rolling resistance due to cornering . Rolling friction generates sound (vibrational) energy, as mechanical energy is converted to this form of energy due to the friction. One of the most common examples of rolling friction is the movement of motor vehicle tires on a roadway , a process which generates sound as

545-399: A tractive force equal to 70% of the maximum traction, slip resistance becomes 10 times larger than the basic rolling resistance. In order to apply any traction to the wheels, some slippage of the wheel is required. For trains climbing up a grade, this slip is normally 1.5% to 2.5%. Slip (also known as creep ) is normally roughly directly proportional to tractive effort . An exception

654-415: A "plate-to-owner" policy, meaning that when a vehicle is sold the seller removes the current plate(s) from the vehicle. Buyers must either obtain new plates or attach plates they already hold, as well as register their vehicles under the buyer's name and plate number. A person who sells a car and then purchases a new one can apply to have the old plates put onto the new car. One who sells a car and does not buy

763-450: A 20% increase in load decreases Crr by 3%. But, if the inflation pressure is not changed, then a 20% increase in load results in a 4% increase in Crr. Of course, this will increase the rolling resistance by 20% due to the increase in load plus 1.2 x 4% due to the increase in Crr resulting in a 24.8% increase in rolling resistance. When a vehicle ( motor vehicle or railroad train ) goes around

872-434: A 5% slip can translate into a 200% increase in rolling resistance. This is partly because the tractive force applied during this slip is many times greater than the rolling resistance force and thus much more power per unit velocity is being applied (recall power = force x velocity so that power per unit of velocity is just force). So just a small percentage increase in circumferential velocity due to slip can translate into

981-432: A Crr of 0.00013 (axle load of 21 tonnes). For empty freight cars with axle loads of 5.5 tonnes, Crr goes up to 0.00020 at 60 km/h but at a low speed of 20 km/h it increases to 0.00024 and at a high speed (for freight trains) of 120 km/h it is 0.00028. The Crr obtained above is added to the Crr of the other components to obtain the total Crr for the wheels. The rolling resistance of steel wheels on steel rail of

1090-401: A by-product. The sound generated by automobile and truck tires as they roll (especially noticeable at highway speeds) is mostly due to the percussion of the tire treads, and compression (and subsequent decompression) of air temporarily captured within the treads. Several factors affect the magnitude of rolling resistance a tire generates: In a broad sense rolling resistance can be defined as

1199-464: A capacity of 170 passengers, rather than the claimed 307. This would be only a slight increase over the typical capacity of conventional bi-articulated buses at the same passenger density (~150 passengers), and less than a typical 33 m (108 ft 3 in) long LRV (~210-225 passengers). Proposals, including vehicle testing, have been made in several countries. Vehicle registration plate A vehicle registration plate , also known as

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1308-554: A car of 1000 kg on asphalt will need a force of around 100  newtons for rolling (1000 kg × 9.81 m/s × 0.01 = 98.1 N). According to Dupuit (1837), rolling resistance (of wheeled carriages with wooden wheels with iron tires) is approximately inversely proportional to the square root of wheel diameter. This rule has been experimentally verified for cast iron wheels (8″ - 24″ diameter) on steel rail and for 19th century carriage wheels. But there are other tests on carriage wheels that do not agree. Theory of

1417-484: A coefficient (ratio)or a multiple thereof. If using pounds or kilograms as force units, mass is equal to weight (in earth's gravity a kilogram a mass weighs a kilogram and exerts a kilogram of force) so one could claim that C r r {\displaystyle C_{rr}} is also the force per unit mass in such units. The SI system would use N/tonne (N/T, N/t), which is 1000 g C r r {\displaystyle 1000gC_{rr}} and

1526-404: A curve, rolling resistance usually increases. If the curve is not banked so as to exactly counter the centrifugal force with an equal and opposing centripetal force due to the banking, then there will be a net unbalanced sideways force on the vehicle. This will result in increased rolling resistance. Banking is also known as "superelevation" or "cant" (not to be confused with rail cant of

1635-409: A cylinder rolling on an elastic roadway also gives this same rule These contradict earlier (1785) tests by Coulomb of rolling wooden cylinders where Coulomb reported that rolling resistance was inversely proportional to the diameter of the wheel (known as "Coulomb's law"). This disputed (or wrongly applied) -"Coulomb's law" is still found in handbooks, however. For pneumatic tires on hard pavement, it

1744-436: A faster rate as the torque becomes higher. The rolling resistance coefficient, Crr, significantly decreases as the weight of the rail car per wheel increases. For example, an empty freight car had about twice the Crr as a loaded car (Crr=0.002 vs. Crr=0.001). This same "economy of scale" shows up in testing of mine rail cars. The theoretical Crr for a rigid wheel rolling on an elastic roadbed shows Crr inversely proportional to

1853-548: A lesser degree. Allowing for repeating letters and digits, the combinations for each of these will be: France was the first country to introduce the registration plate with the enactment of the Paris Police Ordinance on 14 August 1893, followed by Germany in 1896. The Netherlands was the first country to introduce a national registration plate, called a "driving permit", in 1898. Initially these plates were just sequentially numbered, starting at 1, but this

1962-508: A line to connect Sydney Olympic Park to Parramatta . However, concerns were raised that there was only one supplier of the technology, and that the development of "long articulated buses" was "too much in its preliminary phase" to meet the project deadlines. Instead, the plan was to build a light-rail line which would connect to another light-rail route already under construction, so passengers would not have to change vehicles. The Auckland Light Rail Group, in its studies of trackless trams for

2071-417: A loss of traction power which may even exceed the power loss due to basic (ordinary) rolling resistance. For railroads, this effect may be even more pronounced due to the low rolling resistance of steel wheels. It is shown that for a passenger car, when the tractive force is about 40% of the maximum traction, the slip resistance is almost equal to the basic rolling resistance (hysteresis loss). But in case of

2180-403: A new one may, depending on the local laws involved, have to turn the old plates in or destroy them, or may be permitted to keep them. Some jurisdictions permit the registration of the vehicle with "personal" ("vanity" or "cherished mark") plates. In some jurisdictions, plates require periodic replacement, often associated with a design change of the plate itself. Vehicle owners may or may not have

2289-434: A registration plate to be attached to both the front and rear of a vehicle, although certain jurisdictions or vehicle types, such as motorcycles , require only one plate, which is usually attached to the rear of the vehicle. Special vehicles, such as agricultural and construction equipment, might have the license plate attached to other parts of the vehicle. National databases relate this number to other information describing

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2398-883: A slow rigid wheel on a perfectly elastic surface, not adjusted for velocity, can be calculated by C r r = z / d {\displaystyle C_{rr}={\sqrt {z/d}}} where The empirical formula for C r r {\displaystyle C_{rr}} for cast iron mine car wheels on steel rails is: C r r = 0.0048 ( 18 / D ) 1 2 ( 100 / W ) 1 4 = 0.0643988 W D 2 4 {\displaystyle C_{rr}=0.0048(18/D)^{\frac {1}{2}}(100/W)^{\frac {1}{4}}={\frac {0.0643988}{\sqrt[{4}]{WD^{2}}}}} where As an alternative to using C r r {\displaystyle C_{rr}} one can use b {\displaystyle b} , which

2507-590: A standard plate size of 6 inches (15 cm) by 14 inches (36 cm) be adopted through the United States to replace the earlier 6 inches (15 cm) by 12 inches (30 cm) size to allow longer registration numbers to be displayed without excessively tight spacing or excessively thin or narrow characters. In order to combat registration plate fraud, from the 1920s several jurisdictions developed their own anti-fraud typefaces so that characters cannot be painted or modified to resemble other characters. Since

2616-535: A third registration plate on the rear of the trailer. An engineering study by the University of Illinois published in 1960 recommended that the state of Illinois adopt a numbering system and plate design "composed of combinations of characters which can be perceived quickly and accurately, are legible at a distance of approximately 125 feet (38 m) under daylight conditions, and are readily adapted to filing and administrative procedures". It also recommended that

2725-400: A tonne. This lighter weight per passenger, combined with the lower rolling resistance of steel wheels on steel rail means that an N700 Shinkansen is much more energy efficient than a typical automobile. In the case of freight, CSX ran an advertisement campaign in 2013 claiming that their freight trains move "a ton of freight 436 miles on a gallon of fuel", whereas some sources claim trucks move

2834-408: A train is far less than that of the rubber tires wheels of an automobile or truck. The weight of trains varies greatly; in some cases they may be much heavier per passenger or per net ton of freight than an automobile or truck, but in other cases they may be much lighter. As an example of a very heavy passenger train, in 1975, Amtrak passenger trains weighed a little over 7 tonnes per passenger, which

2943-412: A white background with black letters and digits. Plates exist in a long pattern and a rectangular pattern, similar in size and appearance to French plates. The plate is adorned with a small flag of Burkina Faso in the shape of the country, inscribed in a black circle. The letters "BF" appear below the circle, also in black. This circle and BF design is to the right of the long plate and to the upper right of

3052-469: A white background with black letters and numbers. Brazil adopted its former system in 1990, which uses the form ABC•1234, with a dot between the letters and the numbers. A combination given to a particular vehicle follows it from first issue to the scrapyard: it cannot be transferred to another vehicle. Above the combination there was a metallic band with the state abbreviation (SP = São Paulo , RJ = Rio de Janeiro , PR = Paraná , AM = Amazonas , etc.) and

3161-551: A white plate with black lettering and look quite similar to UK suffix style registrations. The format is LLL 000L, where 'L' denotes a letter and '0' denotes a digit. The older series of number plates were black with white or silver lettering. The rear plates in the older series of number plates were yellow and black lettering. According to Kenya National Bureau of Statistics there are over 1,626,380 vehicles on Kenyan roads as at 2011. New-style (post-1983, black lettering on white) Moroccan vehicle registrations have one or two digits to

3270-438: Is hysteresis : A characteristic of a deformable material such that the energy of deformation is greater than the energy of recovery. The rubber compound in a tire exhibits hysteresis. As the tire rotates under the weight of the vehicle, it experiences repeated cycles of deformation and recovery, and it dissipates the hysteresis energy loss as heat. Hysteresis is the main cause of energy loss associated with rolling resistance and

3379-553: Is a different rolling resistance coefficient or coefficient of rolling friction with dimension of length. It is defined by the following formula: F = N b r {\displaystyle F={\frac {Nb}{r}}} where The above equation, where resistance is inversely proportional to radius r {\displaystyle r} seems to be based on the discredited "Coulomb's law" (Neither Coulomb's inverse square law nor Coulomb's law of friction) . See dependence on diameter . Equating this equation with

Autonomous Rail Rapid Transit - Misplaced Pages Continue

3488-440: Is a numeric or alphanumeric ID that uniquely identifies the vehicle or vehicle owner within the issuing region's vehicle register . In some countries, the identifier is unique within the entire country, while in others it is unique within a state or province. Whether the identifier is associated with a vehicle or a person also varies by issuing agency. There are also electronic license plates . In Europe, most governments require

3597-413: Is assumed that all wheels are the same and bear identical weight. Thus:   C r r = 0.01 {\displaystyle \ C_{rr}=0.01} means that it would only take 0.01 pounds to tow a vehicle weighing one pound. For a 1000-pound vehicle, it would take 1000 times more tow force, i.e. 10 pounds. One could say that C r r {\displaystyle C_{rr}}

3706-699: Is asymmetrical and is shifted to the right. The line of action of the (aggregate) vertical force no longer passes through the centers of the cylinders. This means that a moment occurs that tends to retard the rolling motion. Materials that have a large hysteresis effect, such as rubber, which bounce back slowly, exhibit more rolling resistance than materials with a small hysteresis effect that bounce back more quickly and more completely, such as steel or silica . Low rolling resistance tires typically incorporate silica in place of carbon black in their tread compounds to reduce low-frequency hysteresis without compromising traction. Note that railroads also have hysteresis in

3815-414: Is attributed to the viscoelastic characteristics of the rubber. This main principle is illustrated in the figure of the rolling cylinders. If two equal cylinders are pressed together then the contact surface is flat. In the absence of surface friction, contact stresses are normal (i.e. perpendicular) to the contact surface. Consider a particle that enters the contact area at the right side, travels through

3924-434: Is done in this article. They just sum up all the resistance forces (including aerodynamic drag) and call the sum basic train resistance (or the like). Since railroad rolling resistance in the broad sense may be a few times larger than just the pure rolling resistance reported values may be in serious conflict since they may be based on different definitions of "rolling resistance". The train's engines must, of course, provide

4033-554: Is equivalent to forging an official document. Alternatively, the government will merely assign plate numbers, and it is the vehicle owner's responsibility to find an approved private supplier to make a plate with that number. Additionally, citizens can create custom plates, following specific guidelines and naming conventions approved by the Driver and Vehicle Licensing Agency (DVLA). In some jurisdictions, plates will be permanently assigned to that particular vehicle for its lifetime. If

4142-529: Is force per unit mass, where g is the acceleration of gravity in SI units (meters per second square). The above shows resistance proportional to C r r {\displaystyle C_{rr}} but does not explicitly show any variation with speed, loads , torque , surface roughness, diameter , tire inflation/wear, etc., because C r r {\displaystyle C_{rr}} itself varies with those factors. It might seem from

4251-442: Is if the tractive effort is so high that the wheel is close to substantial slipping (more than just a few percent as discussed above), then slip rapidly increases with tractive effort and is no longer linear. With a little higher applied tractive effort the wheel spins out of control and the adhesion drops resulting in the wheel spinning even faster. This is the type of slipping that is observable by eye—the slip of say 2% for traction

4360-420: Is in lb(tow-force)/lb(vehicle weight). Since this lb/lb is force divided by force, C r r {\displaystyle C_{rr}} is dimensionless. Multiply it by 100 and you get the percent (%) of the weight of the vehicle required to maintain slow steady speed. C r r {\displaystyle C_{rr}} is often multiplied by 1000 to get the parts per thousand, which

4469-433: Is in part due to the fact that there is some slipping of the wheel, and for pneumatic tires, there is more flexing of the sidewalls due to the torque. Slip is defined such that a 2% slip means that the circumferential speed of the driving wheel exceeds the speed of the vehicle by 2%. A small percentage slip can result in a slip resistance which is much larger than the basic rolling resistance. For example, for pneumatic tires,

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4578-428: Is largely dependent on the tractive force , coefficient of friction, normal load, etc. "Applied torque" may either be driving torque applied by a motor (often through a transmission ) or a braking torque applied by brakes (including regenerative braking ). Such torques results in energy dissipation (above that due to the basic rolling resistance of a freely rolling, i.e. except slip resistance). This additional loss

4687-501: Is much heavier than an average of a little over one ton per passenger for an automobile. This means that for an Amtrak passenger train in 1975, much of the energy savings of the lower rolling resistance was lost to its greater weight. An example of a very light high-speed passenger train is the N700 Series Shinkansen , which weighs 715 tonnes and carries 1323 passengers, resulting in a per-passenger weight of about half

4796-438: Is notable that slip does not occur in driven wheels, which are not subjected to driving torque, under different conditions except braking. Therefore, rolling resistance, namely hysteresis loss, is the main source of energy dissipation in driven wheels or axles, whereas in the drive wheels and axles slip resistance, namely loss due to wheel slip, plays the role as well as rolling resistance. Significance of rolling or slip resistance

4905-409: Is noteworthy that V s / Ω {\displaystyle V_{s}/\Omega } is usually not equal to the radius of the rolling body as a result of wheel slip. The slip between wheel and ground inevitably occurs whenever a driving or braking torque is applied to the wheel. Consequently, the linear speed of the vehicle differs from the wheel's circumferential speed. It

5014-430: Is only observed by instruments. Such rapid slip may result in excessive wear or damage. Rolling resistance greatly increases with applied torque. At high torques, which apply a tangential force to the road of about half the weight of the vehicle, the rolling resistance may triple (a 200% increase). This is in part due to a slip of about 5%. The rolling resistance increase with applied torque is not linear, but increases at

5123-518: Is reported that the effect of diameter on rolling resistance is negligible (within a practical range of diameters). The driving torque T {\displaystyle T} to overcome rolling resistance R r {\displaystyle R_{r}} and maintain steady speed on level ground (with no air resistance) can be calculated by: T = V s Ω R r {\displaystyle T={\frac {V_{s}}{\Omega }}R_{r}} where It

5232-481: Is several times higher than the neglected resistances. The "rolling resistance coefficient" is defined by the following equation:   F = C r r N {\displaystyle \ F=C_{rr}N} where C r r {\displaystyle C_{rr}} is the force needed to push (or tow) a wheeled vehicle forward (at constant speed on a level surface, or zero grade, with zero air resistance) per unit force of weight. It

5341-403: Is the force resisting the motion when a body (such as a ball , tire , or wheel ) rolls on a surface. It is mainly caused by non-elastic effects; that is, not all the energy needed for deformation (or movement) of the wheel, roadbed, etc., is recovered when the pressure is removed. Two forms of this are hysteresis losses (see below ), and permanent (plastic) deformation of the object or

5450-556: Is the same as kilograms (kg force) per metric ton (tonne = 1000 kg ), which is the same as pounds of resistance per 1000 pounds of load or Newtons/kilo-Newton, etc. For the US railroads, lb/ton has been traditionally used; this is just 2000 C r r {\displaystyle 2000C_{rr}} . Thus, they are all just measures of resistance per unit vehicle weight. While they are all "specific resistances", sometimes they are just called "resistance" although they are really

5559-515: The City Centre to Māngere line, found that trackless trams would have a lower capacity than claimed. The official specifications for the ARRT assume a standing density of eight passengers per square meter, whereas many transit systems have more typical standing densities of four passengers per square meter. Based on that, the 32-metre (105 ft 0 in) long ARRT would more realistically have

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5668-759: The Department of National Defence . All provinces issue plates in which the letters and numbers are embossed so that they are slightly raised above its surface. The territory of Nunavut introduced the first flat registration plate in Canada in July 2012. In the Canadian provinces and territories of Alberta , New Brunswick , Newfoundland and Labrador , the Northwest Territories , Nova Scotia , Nunavut, Prince Edward Island , Quebec , Saskatchewan , and

5777-537: The ISO 3166-2:BO code, is displayed on either a metal tab on older plates or a sticker on newer plates. The current registration plate design consists of a white background with a blue borderline and blue letters and numbers. Serial digits progress sequentially from right to left, with the 000 AAA format followed by the 1 000AAA format and currently the 4 000AAA format. Older plate serials consisted of three numbers followed by three letters (A to Z, except O and Q). They had

5886-453: The Yukon , registration plates are currently only required on the rear of the vehicle. The remaining provinces – British Columbia , Manitoba , and Ontario  – require the registration plates to be mounted on both the front and rear of the vehicle. When a person moves from one province to another, they are normally required to obtain new registration plates issued by

5995-518: The 1990s, many jurisdictions have adopted the FE-Schrift typeface. English uses twenty-six letters (languages such as German , Icelandic and Danish have more letters), so assuming that the letters vs. digits must appear in particular locations (common on plates in most jurisdictions, for instance four decimal digits and two letters where the letters must come first, allowing AB1234 but excluding A12B34), allowing for repeating letters and digits,

6104-422: The 21st century, most plates are made out of aluminium . Metal plates are manufactured through one of two processes: embossing or riveting. For embossing, a plate is placed between dies on each side corresponding to the desired characters and compressed by a press. For riveting, holes are drilled through the plate and then individual letters are riveted one-by-one to the plate. New technology has allowed for

6213-881: The Northwest Territories are shaped like a polar bear but bolt to the standard holes. Nunavut inherited this design on its creation but switched to rectangular plates in 2012. Canadian Forces vehicles that travel on regular roads display registration plates. These vehicles have registration plates issued by the Department of National Defence . Domestic plates were issued by the DND after 1968. Most Canadian provinces offer personalized or vanity license plates, where one can display their own unique combination of characters. Prison inmates in Ontario make registration plates. Rolling resistance Rolling resistance , sometimes called rolling friction or rolling drag ,

6322-440: The above definition of C r r {\displaystyle C_{rr}} that the rolling resistance is directly proportional to vehicle weight but it is not . There are at least two popular models for calculating rolling resistance. The results of these tests can be hard for the general public to obtain as manufacturers prefer to publicize "comfort" and "performance". The coefficient of rolling resistance for

6431-684: The announcement by CRRC, optical guided buses have been in use in a number of cities in Europe and North America, including in Rouen as part of Transport Est-Ouest Rouennais , in Las Vegas as a segment of Metropolitan Area Express BRT service (now discontinued), and in Castellón de la Plana as Line 1 in TRAM de Castellón network  [ es ] . The guidance system technology used on these systems

6540-472: The bearings, but a train car with steel wheels running on steel rails will roll farther than a bus of the same mass with rubber tires running on tarmac/asphalt . Factors that contribute to rolling resistance are the (amount of) deformation of the wheels, the deformation of the roadbed surface, and movement below the surface. Additional contributing factors include wheel diameter , load on wheel , surface adhesion, sliding, and relative micro-sliding between

6649-446: The claims about cost and quick installations, and argued that ART is a proprietary technology with little deployment worldwide. Other experts have argued the technology is overhyped, that optical guidance technology is not new, and that current proposals largely represent a repackaging of the bus as a rail-replacement technology. As of 2022 there are no systems outside of China and few proposals. That may be because: Proponents have argued

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6758-480: The combinations for each of these will be: If letters and digits can appear in any order, it is problematic to allow both the letter O and the digit 0 to be used. Even if the license plate uses distinguishable characters for the two, someone transcribing the plate may not know which symbol has which meaning, and the owner of plate EM6F9VO may get in trouble for something the owner of plate EM6F9V0 did. Other letter–digit pairs, like I and 1, may be similarly problematic to

6867-456: The contact patch and leaves at the left side. Initially its vertical deformation is increasing, which is resisted by the hysteresis effect. Therefore, an additional pressure is generated to avoid interpenetration of the two surfaces. Later its vertical deformation is decreasing. This is again resisted by the hysteresis effect. In this case this decreases the pressure that is needed to keep the two bodies separate. The resulting pressure distribution

6976-451: The decentralized phase (until 1972) and the centralized one (since 1972). During the decentralized phase, registration plates were assigned by each municipality or by the provinces, while during the second phase, the national state took charge of standardizing and centralizing the design and style. Argentina has used the ABC 123 format since 1995. However, from 2016, new registration plates with

7085-755: The development of digital license plates. In 2018, Michigan approved Public Act 656, making electronic license plates legal. Early 20th century plates varied in size and shape from one jurisdiction to the next, such that if someone moved or the car was resold in a new area, new holes would need to be drilled into the automobile (often on the bumper) to support the new plate, or an adapter plate be made. Standardization of plates came in 1957, when automobile manufacturers came to agreement with governments and international standards organizations. While peculiar local variants exist, there are four basic standards worldwide: Additional sizes include: Previous sizes included: Algerian registration plates are manufactured according to

7194-404: The driving wheel(s) becomes greater than the vehicle speed due to slippage. Since power is equal to force times velocity and the wheel velocity has increased, the power required has increased accordingly. The pure "rolling resistance" for a train is that which happens due to deformation and possible minor sliding at the wheel-road contact. For a rubber tire, an analogous energy loss happens over

7303-410: The energy dissipated by vibration and oscillation of both the roadbed and the vehicle, and sliding of the wheel on the roadbed surface (pavement or a rail). But there is an even broader sense that would include energy wasted by wheel slippage due to the torque applied from the engine . This includes the increased power required due to the increased velocity of the wheels where the tangential velocity of

7412-418: The energy to overcome this broad-sense rolling resistance. For tires, rolling resistance is defined as the energy consumed by a tire per unit distance covered. It is also called rolling friction or rolling drag. It is one of the forces that act to oppose the motion of a driver. The main reason for this is that when the tires are in motion and touch the surface, the surface changes shape and causes deformation of

7521-401: The entire tire, but it is still called "rolling resistance". In the broad sense, "rolling resistance" includes wheel bearing resistance, energy loss by shaking both the roadbed (and the earth underneath) and the vehicle itself, and by sliding of the wheel, road/rail contact. Railroad textbooks seem to cover all these resistance forces but do not call their sum "rolling resistance" (broad sense) as

7630-739: The force per the rolling resistance coefficient , and solving for b {\displaystyle b} , gives b {\displaystyle b} = C r r r {\displaystyle C_{rr}r} . Therefore, if a source gives rolling resistance coefficient ( C r r {\displaystyle C_{rr}} ) as a dimensionless coefficient, it can be converted to b {\displaystyle b} , having units of length, by multiplying C r r {\displaystyle C_{rr}} by wheel radius r {\displaystyle r} . Table of rolling resistance coefficient examples: [3] For example, in earth gravity,

7739-405: The front and rear of the vehicle. Motorcycles (50cc or more) must be licensed and only bear rear plates. Registration is performed at the local police or Gendarmerie station. The first digits of the plate indicate the province in which the vehicle is registered. Only plates which meet government standards and are sold by licensed dealers may be fitted. Private passenger car registration plates have

7848-534: The glare. The ART is powered by lithium–titanate batteries and can travel a distance of 40 km (25 miles) per full charge. The batteries can be recharged via current collectors at stations. The recharging time for a 3 to 5 km (1.9 to 3.1 mi) trip is 30 seconds and for a 25 km (16 mi) trip, 10 minutes. A 2018 article by a sustainability academic argued trackless trams could replace both light-rail and bus rapid transit due to low cost, quick installation and low emissions. Others have disputed

7957-447: The government holds a monopoly on the manufacturing of vehicle registration plates for that jurisdiction. Either a government agency or a private company with express contractual authorization from the government makes plates as needed, which are then mailed to, delivered to, or picked up by the vehicle owners. Thus, it is normally illegal for private citizens to make and affix their own plates, because such unauthorized private manufacturing

8066-548: The initial suggested capital cost savings were illusory. A November 2020 proposal for a trackless tram system in the City of Wyndham , near Melbourne, posited a cost of $ AU23.53M per km for roadworks, vehicles, recharge point and depots. Recently completed light rail systems in Australia have had costs of between $ AU80M and $ AU150M per km. The Government of New South Wales considered the system as an alternative to light rail for

8175-453: The lack of rails means cheaper construction costs. Multi-axle hydraulic steering technology and bogie-like wheel arrangement could allow lower swept path in turns, thus requiring less side clearance. The minimum turning radius of 15 m (49 ft 3 in) is similar to buses. However, because the ART is a guided system, ruts and depressions could be worn into the road by the alignment of

8284-409: The large number of wheels, so reinforcement of the roadway to prevent those problems may be as disruptive as the installation of rails in a light rail system. Researchers in 2021 found evidence of significant road wear due to trackless tram vehicles, which undermined claims of quick construction, with the researchers finding significant road strengthening was required by the technology. The suitability of

8393-420: The left, the country's name centered and country flag on the right. On the bottom left, there is the international vehicle registration code for Brazil: BR . The plates are always white: the letter coloring indicates the category (e.g., black on white: private; blue on white: official, police, fire departments, etc.; red on white: taxis, buses, paid freight, etc.). A new format based on the previous one, ABC1D23,

8502-454: The letter Q , to avoid confusion with O . Botswana number plates have a reflective white front and yellow rear background, and black lettering. Government vehicles all have the prefix "BX", these number plates have a white reflective background with red lettering at the front and white on red at the rear. After 'BX' are the last two numerals of the date of issue and then up to four digits issued serially. Botswana Defence Force vehicles have

8611-616: The license plate (when that information appears on the plate). Plates are designed to conform to standards with regard to being read by eye in day or at night, or by electronic equipment. Some drivers purchase clear, smoke-colored or tinted covers that go over the registration plate to prevent electronic equipment from scanning the registration plate. Legality of these covers varies. Some cameras incorporate filter systems that make such avoidance attempts unworkable, usually with infra-red filters. Vehicles pulling trailers , such as caravans and semi-trailer trucks , are typically required to display

8720-519: The logo of Mercosur and the AB 123 CD format were implemented. Both formats coexist temporarily. Bolivia 's current registration plate system consists of four numbers followed by three letters. At the top of the plate, "BOLIVIA" is spelled out. At the top left corner, the Bolivian flag may be present, and at the top right corner, a letter denoting the department in which the car is registered, according to

8829-417: The name of the municipality in which the vehicle title owner resides. During the first registration of a new vehicle, the registering state issues a registration plate to the vehicle rather than owner, and the serial stays with the vehicle for its life. Brazil, as a member of Mercosur , from September 2018 on, began a new registration system where plates have a blue band at the top with the logo of Mercosur on

8938-495: The new place of residence. In 1956, all North American passenger vehicle registration plates (except for French-controlled St. Pierre and Miquelon ), were standardized at a size of 6 in × 12 in (152 mm × 305 mm), although a smaller size is used for certain vehicle classes, such as motorcycles , and for the state of Delaware's historic alternate black and white plates, which are 5.25 in × 9.5 in (133 mm × 241 mm). The plates of

9047-414: The option to keep their original plate number, and may have to pay a fee to exercise this option. Alternately, or additionally, vehicle owners have to replace a small decal on the plate or use a decal on the windshield to indicate the expiration date of the vehicle registration , periodic safety and/or emissions inspections or vehicle taxation. Other jurisdictions have replaced the decal requirement through

9156-464: The prefix "BDF" in white on an 'army' green background. Diplomatic vehicles' number plates start with two numerals which indicate the embassy to which they are attached, then two letters CD (Corps Diplomatique), CC (Consular Corps status) or CT (Foreign Technical and Advisory personnel) and another three digits which are serial. The official car of the Head of Mission uses the letters CMD rather than CD and

9265-468: The private vehicle uses CDA. This series is allocated by the Minister of Foreign Affairs. Botswana is the former British Protectorate of Bechuanaland , and number plates then used a 'BP' prefix (then BPA, BPB, etc.) followed by up to three digits, in white on black background, the plates being made in the characteristic style of South Africa at that time. Vehicles are fitted with registration plates in

9374-412: The rectangular plate. Motorcycle plates are similar to rectangular automobile plates, but smaller. Commercial registration plates are similar in appearance to private plates, but the background is blue, and the writing and circle are white. Security forces plates are black with white letters. They are adorned with the emblem of the relevant security service. The current scheme of regular license plates

9483-419: The right of the plate to indicate the town of registration. Each number is separated by a vertical line. To the left of the plate are a series of up to 5 digits issued consecutively. These are separated from the town of registration digits by a hyphen. Earlier plates (1972–1983, black lettering on white. Pre-1972, white lettering on black) differed in that they could have either one or two numbers to indicate

9592-438: The road and if the proximity reduces below a given level, it alerts the driver by a warning sign. The Route Change Authorization is a navigation device, which analyzes the traffic conditions on the chosen route and can recommend a detour to avoid traffic congestion. The Electronic Rearview Mirrors work with remotely adjustable cameras and provide a clearer view than conventional mirrors, including an auto dimming device to reduce

9701-481: The roadbed structure. In the broad sense, specific "rolling resistance" (for vehicles) is the force per unit vehicle weight required to move the vehicle on level ground at a constant slow speed where aerodynamic drag (air resistance) is insignificant and also where there are no traction (motor) forces or brakes applied. In other words, the vehicle would be coasting if it were not for the force to maintain constant speed. This broad sense includes wheel bearing resistance,

9810-422: The same standards as their French counterparts (prior to 2009), using the same font and dimensions – although there has been a recent tendency to apply custom typefaces (impact and century gothic have been observed). Normal vehicles have number plates starting with the letter B , followed by three digits, followed by three letters. The digits and letters are assigned by a registrar. The three letters never include

9919-442: The so-called slip resistance involves friction , therefore the name "rolling friction" is to an extent a misnomer. Analogous with sliding friction , rolling resistance is often expressed as a coefficient times the normal force. This coefficient of rolling resistance is generally much smaller than the coefficient of sliding friction. Any coasting wheeled vehicle will gradually slow down due to rolling resistance including that of

10028-465: The square root of the load. If Crr is itself dependent on wheel load per an inverse square-root rule, then for an increase in load of 2% only a 1% increase in rolling resistance occurs. For pneumatic tires, the direction of change in Crr (rolling resistance coefficient) depends on whether or not tire inflation is increased with increasing load. It is reported that, if inflation pressure is increased with load according to an (undefined) "schedule", then

10137-430: The sum of components ): Wheel bearing torque losses can be measured as a rolling resistance at the wheel rim, Crr . Railroads normally use roller bearings which are either cylindrical (Russia) or tapered (United States). The specific rolling resistance in bearings varies with both wheel loading and speed. Wheel bearing rolling resistance is lowest with high axle loads and intermediate speeds of 60–80 km/h with

10246-460: The surface (e.g. soil). Note that the slippage between the wheel and the surface also results in energy dissipation. Although some researchers have included this term in rolling resistance, some suggest that this dissipation term should be treated separately from rolling resistance because it is due to the applied torque to the wheel and the resultant slip between the wheel and ground, which is called slip loss or slip resistance. In addition, only

10355-464: The surfaces of contact. The losses due to hysteresis also depend strongly on the material properties of the wheel or tire and the surface. For example, a rubber tire will have higher rolling resistance on a paved road than a steel railroad wheel on a steel rail. Also, sand on the ground will give more rolling resistance than concrete . Sole rolling resistance factor is not dependent on speed. The primary cause of pneumatic tire rolling resistance

10464-580: The system for winter climates with ice and snow has not yet been proven. The higher rolling resistance of rubber tires requires more energy for propulsion than the steel wheels of a light rail vehicle. A few abandoned proposals for light-rail lines have been revived as ART proposals because of the lower projected costs. However, a different report, by the Australian Railways Association, which supports light rail, said there were reliability questions with ART installations, implying

10573-410: The tire. For highway motor vehicles, there is some energy dissipated in shaking the roadway (and the earth beneath it), the shaking of the vehicle itself, and the sliding of the tires. But, other than the additional power required due to torque and wheel bearing friction, non-pure rolling resistance doesn't seem to have been investigated, possibly because the "pure" rolling resistance of a rubber tire

10682-521: The town of registration. The group of digits was separated from the rest of the plate by a vertical line. The current plates use numerals without script. Earlier plates used numerals and included Arabic script . South African number plates are unique in each of the provinces . Each province has its own number plate design and colors, as well as numbering scheme. The history of registration plates in Argentina can be broken down in two major phases:

10791-418: The use of computerization: a central database maintains records of which plate numbers are associated with expired registrations, communicating with automated number plate readers to enable law-enforcement to identify expired registrations in the field. Plates are usually fixed directly to a vehicle or to a plate frame that is fixed to the vehicle. Sometimes, the plate frames contain advertisements inserted by

10900-452: The vehicle is either destroyed or exported to a different jurisdiction, the plate number is retired or reissued; exported vehicles must be re-registered in the jurisdiction of import. China requires the re-registration of any vehicle that crosses its borders from another country, such as for overland tourist visits, regardless of the length of time it is due to remain there; this has to be arranged with prior approval. Other jurisdictions follow

11009-439: The vehicle service centre or the dealership from which the vehicle was purchased. Vehicle owners can also purchase customized frames to replace the original frames. In some jurisdictions registration plate frames are illegal or have design restrictions. For example, many states, like Texas, allow plate frames but prohibit plate frames from covering the name of the state, province, district, Native American tribe or country that issued

11118-426: The vehicle to automatically follow a route defined by a virtual track of markings on the roadway. A steering wheel also allows the driver to manually guide the vehicle, including around detours. A Lane Departure Warning System helps to keep the vehicle in its lane and automatically warns, if it drifts away from the lane. A Collision Warning System supports the driver on keeping a safe distance with other vehicles on

11227-407: The vehicle, such as the make, model , colour , year of manufacture, engine size, type of fuel used, mileage recorded (and other similar data in jurisdictions where vehicles are regularly inspected for roadworthiness every year or two), vehicle identification number (chassis number), and the name and address of the vehicle's registered owner or keeper. In the vast majority of jurisdictions,

11336-583: Was called Visée under their original developer Matra, and is now named Optiguide after being acquired by Siemens. An ART vehicle with three carriages is approximately 30 m (98 ft 5 in) long. It can travel at a speed of 70 km/h (43 mph) and can carry up to 300 passengers. A five-carriage ART vehicle provides space for 500 passengers. A four carriage model was introduced in 2021 which can carry 400 passengers. Two vehicles can closely follow each other without being mechanically connected, similarly to multiple unit train control . The entire ART has

11445-476: Was changed in 1906. In the United States , where each state issues plates, New York State has required plates since 1903 (black numerals on a white background) after first requiring in 1901 only that the owner's initials be clearly visible on the back of the vehicle. At first, plates were not government-issued in most jurisdictions and motorists were obliged to make their own. In 1903, Massachusetts

11554-459: Was implemented. All used cars, when transferred to another owner, must change to the new format keeping their registration, where only its second number (the fifth position of the alphanumeric combination) shall change to a letter, following the pattern: 0=A, 1=B, 2=C, 3=D, ... 9=J. As of 2020 , both formats coexist for the time being. In Canada, license plates are issued on the provincial or territorial level. Federally issued plates are only used by

11663-661: Was introduced in 1985. It has AB1234V formats or AB123VH where AB is the code region, 1234 is the number, and SH is the series. The regular plate has an orange background with black marks. Since 2005, to reflect the German FE font used, on the left side of the plate are the emblems of the Economic Community of Central African States code and the CMR emblem. The current series of vehicle registration plates in Kenya are on

11772-484: Was issued for a Clément-Talbot on 31 October 1900 in Palma de Mallorca . 256 vehicles were registered between 1901 and 1905. The earliest plates were made of enamel on metal or ceramic with no backing, which made them fragile and impractical. Few of these early plates survived. Later experimental materials include cardboard , leather , plastic , and, during wartime shortages, copper and pressed soybeans . As of

11881-551: Was the first state to issue plates. In 1928, Idaho was the first state to put a logo on the plate (the "Idaho Potato"). In Spain , the first law to define rules on non-animal vehicle traction was Real orden de 1897 de circulación de vehículos cuyo motor no sea la fuerza animal and the registration of vehicles was defined as a provincial task in the Reglamento de 1900 para el servicio de coches automóviles por las carreteras . The first Spanish registration plate, PM–1,

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