[雙語翻譯]--外文翻譯---鐵路基礎設施的維修窗口成本效率與交通影響（節(jié)選）

1、中文 中文 3200 字， 字，1850 單詞， 單詞，1 萬英文字符 萬英文字符出處： 出處：Lidén T, Joborn M. Dimensioning windows for railway infrastructure maintenance: Cost efficiency versus traffic impact[J]. Journal of Rail Transport Planning & Ma

2、nagement, 2016, 6(1):32-47.Dimensioning windows for railway infrastructure maintenance: Cost efficiency versus traffic impactTomas Lide´n, Martin JobornAbstractThe Swedish Transport Administration is introducing a

3、new regime, called maintenance windows, for allocating train free slots reserved for maintenance tasks on the railway infrastructure. In this paper, a model for the assessment and the dimensioning of such maintenance

4、windows is presented, which considers marginal effects on both the maintenance cost and the expected train traffic demand. The aim is to establish quantitative measures that can be used for comparing conflicting capac

5、ity requests from infrastructure maintenance and traffic operations on railway networks. The model is demonstrated in a cost benefit analysis for a real life case study on the Swedish Northern Main Line. Keywords: Main

6、tenance planning Cost benefit analysis Railway infrastructureIntroductionRailway infrastructure maintenance is of crucial importance in order to obtain a well functioning transportation system. The actual maintenance wo

7、rk consists of a large amount of different activities, requiring considerable resources and large budgets. The European countries are reported to allocate 15e25 billion V annually on maintenance and renewals for a rai

8、lway system consisting of about 300,000 km of track, giving an average of 70,000V per km track and year (see EIM-EFRTC- CER Working Group (2012)). There is however an inherent conflict in deciding how to assign maintena

9、nce work slots and train operation paths since these activities are mutually exclusive. This planning conflict becomes crucial on lines with high traffic density and/or around the clock operation - especially when tra

10、ffic demand and maintenance needs are increasing. This is the case in Sweden, where passenger and freight trains are mixed on the same infrastructure and a large increase in passenger traffic, both regional and inter-

11、regional, have forced many freight trains to be run during night time, leaving very few opportunities for maintenance. In addition, a far reaching deregulation has been going on since the 1980s in Europe, with the over

12、all purpose of opening up for commercial competition in the railway area. For infrastructure maintenance, this trend has extended the use of maintenance contractors, which raises more concerns regarding contractual for

13、ms, public procurement as well as planning. All these factors e the large volumes, the interrelation between maintenance and traffic, the organizational aspects - motivate efficient and coordinated planning as well as

14、 more research. This is further accentuated by increasing needs for infrastructure manager will propose regular, 2e6 h train free slots before the timetable is constructed. Thus, the maintenance windows are given as a i

15、nput to the yearly timetable process. In addition, the maintenance windows will be dimensioned and constructed before the procurement of maintenance contracts and will remain more or less unchanged during the contract

16、 period, giving stable planning and quotation conditions for the contractors. The goal is to perform almost all planned maintenance on work possessions within the stipulated maintenance windows. Note that maintenance

17、windows are predetermined train free slots in the timetable, while possessions are the actual reservations for specific work tasks. Hence, the basic idea is to go from a situation with many, small and fragmented work

18、possessions squeezed into an already published timetable (which causes changes and disturbances for the train operations), to a situation with few, large and regular maintenance windows preplanned before the timetable

19、is constructed and the maintenance contracts procured. The overall aim is to increase efficiency, reduce cost as well as planning burden and also to improve robustness and punctuality. We will not analyse all these as

20、pects but will focus on the consequences for maintenance, train traffic and transportation demand. A more complete study of the pro's and con's when introducing maintenance windows must consider several other

21、factors, like the long term unavailability of train capacity, network wide effects, planning efficiency etc. The dimensioning and construction of maintenance window patterns is a long term planning problem of crucial i

22、mportance, since it lays the foundation for both the maintenance work and the traffic operation. It must be based on reasonable predictions about the maintenance work volumes as well as the traffic demand for period l

23、engths of 5e10 years (corresponding to the maintenance contract length e which is 5 þ 2 years in Sweden). Now we turn to the content and organization of the actual maintenance jobs. A maintenance work shift typica

24、lly consists of three parts: Preparation: Crew and equipment must be transported to the working site, where the resources will be organized, prepared and set up. The working area must be secured, by proper signalling a

25、nd electrification measures which includes registration and acknowledgement from the traffic control centre(s). Maintenance: The actual work task(s) can be of varying type, where some tasks (e.g. inspection and vegetat

26、ion clearance) require short times, say 1/2 e 1 h, while others (e.g. welding, switch machine work) take longer to finish, say 2e6 h. Termination: When the maintenance task has been finished, the site must be cleared,

27、resources and safety measures removed and finally the responsibility handed back to the traffic control centre(s). We will label preparation and termination as overhead time, while the actual maintenance job is called

28、task time. Together they form the shift time and the sum of all shifts is called work time. Our basic assumption is that the tasks are divisible such that, e.g. a 2 h task can be performed on two possessions. The overh

29、ead time, on the other hand, is directly proportional to the number of possessions. Further we will consider that some part of the overhead time can be performed outside the track possessions, while the rest must be d