Capacity

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'''Russian: [http://ru.scm.gsom.spbu.ru/index.php/Пропускная_способность Пропускная способность]'''
'''Russian: [http://ru.scm.gsom.spbu.ru/index.php/Пропускная_способность Пропускная способность]'''
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Throughput.
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==Capacity==
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The possibility of a mode of transport to transport most of the estimated value of the bandwidth.
The possibility of a mode of transport to transport most of the estimated value of the bandwidth.
The capacity of means of communication or transport of the object is expressed by the largest number of units of rolling stock, which can be served by the transport device for a certain period of time in its technical equipment and technologies.
The capacity of means of communication or transport of the object is expressed by the largest number of units of rolling stock, which can be served by the transport device for a certain period of time in its technical equipment and technologies.
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There are: cash, needs, and productive capacity.
There are: cash, needs, and productive capacity.
Cash - this is the maximum size of vehicles that can be implemented depending on the technical equipment.
Cash - this is the maximum size of vehicles that can be implemented depending on the technical equipment.

Revision as of 19:02, 15 December 2012

Russian: Пропускная способность

Capacity

The possibility of a mode of transport to transport most of the estimated value of the bandwidth. The capacity of means of communication or transport of the object is expressed by the largest number of units of rolling stock, which can be served by the transport device for a certain period of time in its technical equipment and technologies.

There are: cash, needs, and productive capacity. Cash - this is the maximum size of vehicles that can be implemented depending on the technical equipment. Required - determined by the number of vehicles required to carry out the plan (set of) traffic. Productive capacity of sites is determined on the basis of data on the capacity of individual devices, and trends in general - on the basis of productive capacity of land. For example, the productive capacity of individual sections of rail installed on the following elements: - To overtake (the number of main roads, the length of spans, the profile path, automation systems and communications, track the development of separate items, the device power supply); - By station (receiving-way arrow, and throat); - On farm depot (stalls for periodic inspection and repair of electric and diesel locomotives, locomotive devices for equipment and running the way); - For power devices (traction units, power transformers and traction substations contact network). The minimum capacity of one of these elements may limit the capacity of the production unit as a whole and determine the value of effective bandwidth. Cash bandwidth can be generally defined by the formula:

                               (1)

where Tr - current time period is determined by the bandwidth, h; Tm - processing time required for processing (badges, service) adopted a unit of traffic flow (1 m, 1 m 3, a car, a ship, etc.) for a uniform and continuous use of the device or system within the estimated time. For different devices, and transportation systems, this formula is concretized disclosing the value of technological time Tm. Capacity of the railway line is the greatest number of trains and steam trains set of mass, which can be skipped in a unit time (day, hour), depending on the existing permanent facilities, type and capacity of rolling stock and the methods adopted by the organization trains (such as graphics). The capacity is set for sections of railway lines with the same all over the technical equipment, cargo capacity and the size of passenger traffic. The primary end point of these plots are the precinct and marshalling yards, the band of suburban station areas, and sometimes the intermediate station of origin and settlement flows. The capacity of each item is determined by the plot of his daily or hourly productivity and power consumed in the service of one pair of trains or trains. The capacity of the site is determined by the bounding ferrying:

                          (2)

where T - the period of the schedule to the delimiting the stretch, including; k - number of pairs of trains or trains this direction, the noise for a period of the chart. This formula gives a value of N in the absence of technological losses and the total reliability of the technology. If this condition is not met, then the value of the numerator in the formula is reduced accordingly.

The capacity of sections of railway lines is calculated according to surpass the original schedule for the parallel and is determined to train only one category, usually trucks. Then take into account the impact on the capacity of trains coming from the other rates, that is calculated capacity of non-parallel graph.

The capacity of the parallel schedule depends on the time course of the distillation, the station spacing and intervals in the package, as well as track development of separate items. In general, the capacity (steam train) ferrying expressed by dependence:

                  And (3)

where Tper - the period of the graph, min.; ttehn - the duration of maintenance window, min.; αn - coefficient of reliability of technical devices. With unparalleled graphics throughput for freight traffic expressed in number of freight trains of a given mass and velocity, which can be skipped on a site or a line when applying a given number of passengers, freight and expedited teams train. Part-time hours, which is due to the repetition of these trains can not be used for freight trains, called the time of removal. The capacity for predominantly freight movement, pairs of trains is expressed by dependence:

And (4)

where N - capacity of the line for freight traffic with parallel graph; Nps, Nsb, Nusk - the number of passengers, respectively, partial and expedited freight trains;

 ,, - Respectively, the coefficients of the pickup truck passenger trains, freight teams and accelerated trains.

Line capacity is calculated from the full use of all facilities. However, it must have a reserve that is installed on the technical and economic reasons, expressed as the difference between the cash (or projected) capacity and demand, i.e. given (or planned) in the future. The capacity of the road is defined as the sum of the capacities of the bands. The capacity of one lane of the road is calculated by the formula (1) Subject to:

                   And (5)

where - the vehicle stopping distance is equal to (a - acceleration of the motion);

 - The path traversed by a driver's reaction time is equal to;
 - The length of the car.

The capacity of river routes determined by the formula (1), but much depends on the capacity of gateways and the time of their employment by the courts:

                         And (6)

where - the time required for locking vessels proceeding in opposite directions; 2 - coefficient allowing for locking of vessels in both directions; m - number of vessels with a capacity in the lock chamber at the same time. Marine natural ways to have no restrictions on capacity. The capacity of maritime transport is determined by the ability to pass through the vessels and equipment of the port. In air transport capacity constraints, as a rule, depend on the capacity of airports to accept and recover aircraft. For continuous modes of transportation (pipeline and pipeline) capacity shall be determined by the formula (1) with a time of cargo a certain type:

                     And (7)

where q - volume or weight of the load at 1 m path length (pipe or pipeline); v - speed of movement of goods in the appropriate units, m / sec, m / min. The capacity of processing items, equipment, and repair of rolling stock on all modes of transport (stations, ports, airfields, depots, backwaters, garages, etc.) is calculated by the formulas of the same type but having different parameters specific to the appropriate mode of transport. The development of the growing freight traffic is the need to increase the capacity of rail lines, which. defined as the difference between needs and capacities of cash, can be achieved through organizational and technical and reconstructive measures. Carrying capacity. Carrying capacity is usually defined in general as to the railway line, and for other means of communication. There are cash needs, and carrying capacity of the line obtained as a result of the possible use of its capacity for cargo transportation with the appropriate needs of passenger traffic.

Carrying capacity - the maximum value of cargo (in tons net per annum), which can be mastered within a year the line is determined for each area separately. Carrying capacity of the railway line depends on the bandwidth, the rules of mass freight trains, structures of train flow by categories of trains and freight traffic, to leave and expresses the power line used for freight traffic, while ensuring a given number of permits and other passenger trains emergency treatment. Carrying capacity is determined by the number of locomotives, wagons and other means of variables (fuel, electricity) and the security staff (locomotive brigades on duty at the station, etc.). It depends on the proportion of cash in the capacity of the line for freight traffic, the average weight of a train in the area, comparisons of net and gross train, as well as the number of teams and express trains, and is given by:

                    And (8)

where,, - the average gross weight of freight trains, respectively, normal, accelerated, modular, t;

 ,, - The ratio of net weight of the train to the gross mass of the relevant group of freight trains;
 - Coefficient of irregularity of monthly traffic.


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