Clock-face scheduling

A clock schedule is a schedule, to be operated at the lines of public transport in regular, periodically repeating intervals. The number of departures in a given period is called the frequency.

Were developed clock schedules in the transport of the late 19th century, for example, for trams. Also railways in the metropolitan area ( for example, on the Berlin Stadtbahn ) or horse bus lines already drove with fixed pitches.

Goal of a clock movement is to increase the attractiveness and uses a means of transport or the existing infrastructure - for example, shift to single-track lines - optimal use. The clock schedule provides the passenger the advantage of better memorability of departure times, as these are repeated in always equal time intervals, usually every hour on the same minutes. A uniform clock can also lead to an improved offer in low demand periods. For transport company that is regularly repeated operation is interesting to vehicles and infrastructure can be cut accurately.

The opposite of a building on solid bars timetable are transport services, which are carried out at irregular intervals. Demand-driven schedules, there are today in the form of call lines also as regular services, the clock is available on most orders by phone and actually performed cycle operation does not take place.

• 5.1 Example
• 5.2 Time -distance diagram
• 5.3 demarcation
• 5.4 definition
• 5.5 Significant Roadmap extract

Features to create a synchronized timetable

Clock schedules are used mainly in transport and cable cars for a long time, since thereby provide optimal orbital periods. The schedules created by the grouping of trips on a common path to lines on which then the easily remembered clock schedule applies. A round consists of the driving time, the time for the change of direction and other waiting times as well as the boarding and alighting times at intermediate stations. The round trip time determines the maximum possible on a track pitch (one stop is at least as often operated arrives as a particular vehicle there), the ratio of round trip time to pitch is equal to the number of vehicles used simultaneously on the line.

With an orbital period of 40 minutes at a single track railway, with three alternatives in the route quarter points, with a vehicle ( a train composition ) a timing sequence of 40 minutes are possible. With two vehicles located 20 minutes ( crossing in the middle distance ) and found four vehicles 10 minutes ( crossing in all three passing places ). Four vehicles, the maximum link capacity is reached. When a clock schedule with these times but no delays may occur as this would no longer complied with for the rest of the day the clock. Each long cycle sequence, like this example, 15 /30 Minutes, would only reduce the capacity at constant personnel costs. This would be useful only if connection is to be made ​​to another line in this cycle or reserves for ensuing delays are regularly needed.

In the public transport (PT ), a different clock at different peak hours ( full load and normal load, low load and late rush hour ) is often offered. During the off-peak time ensures the minimum supply in the peak hours, the normal load is applied during the day, at peak times the trips are compacted to full load. A constant cycle affects at peak times disadvantageous, when the vehicle capacity is limited. This can be remedied by between clocked Einsatzumläufe or by increasing the capacity of the vehicles ( use of double features, outflanking, bus trailer in Switzerland, articulated buses, etc.).

Bound line interval timetable

For each transport line a separate schedule can be created, without connections to respect to other lines. It then creates a line- bound schedule or when a clockface is applied, a line- bound clock schedule. Already here may be required dependent plans if a connection needs to be continued in suburban areas with bus routes for example on a tram endpoint. There is then a broken connection is not required for the practice, a single, but consisting of two parts tables.

For transport with a fixed orbital period such timetables are already useful for cost reasons, even if they are not part of a clockface overall network. Because this will be an even more effective and thus personnel and vehicle use.

It makes sense to line bound timetables particularly for offerings with rapid cycles. If vehicles with the same destination follow in close succession, transfer times are always very short and to connections need not be taken in the scheduling or even waiting in operation. Already at 20 -minute cycles, however, a coordination of the timetables of intersecting lines is attached. For this purpose, first the clock position of various lines against each other and thus the transfer time can be minimized.

Even in urban areas there are lines with low clock frequency. Here it is possible to introduce other lines timed. Likewise, urban transport can bring travelers at a railway station or pick up from there. If this only takes place a roadmap focus on another mode of transport, yet there is no comprehensive traffic system. If the cycle times of various modes of transport and lines but successive tuned so that it forms an extensive network or system, caused rendezvous concepts or integral clock schedules.

Rendezvous Concepts

The concentration of lines to a central transfer point (often a bus station) and the establishment of a rendezvous concept, in which all lines simultaneously arrive and depart shortly thereafter together again, is a modern way of the line link. It is waiting for delayed vehicles. The aim is to shorten the connection times in all directions for a few minutes, be adopted as a basis often five minutes transitional period. In operation, however, to this period often by earlier arriving late or vehicles, high ridership (eg school transport ) or consideration for mobility-impaired passengers. Due to the waiting times at transfer hubs such, the appeal will be lost by solid lines.

Examples of such systems are found especially at night nets (including road or rail vehicles, such as " Night Star Transport " in Hanover) and modern urban bus networks in medium-sized cities. Networking with short connections is limited to urban transport, regional buses or trains at the station are not included or are limited to single integrated into urban transport offers ( for example, in a city bus integrated regional buses). Such concepts require specially -developed central interchange points, because they are operated at the same time by many vehicles. Especially in tight inner city areas, the high space requirement be a reason to seek other concepts.

Integral timetable ( ITF)

As an integral timetable ( ITF), a concept is understood, in which the clock schedules of individual lines are linked through a systematic coordination in railway stations to a network-wide, vertakteten quote system. The ITF is true not only on a single line ( at a certain distance = 'edge' ) or a transfer point ( = " nodes"), but for the entire area (or network linked by edges = nodes). The timetable is thus harmonized with in total. The main feature of a basic interval timetable is that there is more than one central point of transfer, it is the extension of the rendezvous concept to as many transfer points.

In an ideal ITF the clock schedules of lines are coordinated to a coordinated, vertakteten overall time schedule, a combination of lines in direction and the opposite direction ( ITF nodes ) is performed in selected nodes with the objective to maximize the number of optimal connections. Can this ideal under practical conditions only with restrictions, one speaks of a basic interval timetable in a broader sense. Here, for example, links of some lines a deviating clock for individual lines are omitted to other lines at specific connection points, offered or thinned while available at certain periods of operation or enhanced. From a basic interval timetable in a broader sense is used when introducing an ITF accompanied by measures to increase the attractiveness of passenger transport, for example, offer improvements, modern vehicles and access points.

An integral timetable is based on the normalized orbital periods. A line of vehicle must be an " edge travel time " ( = the travel time between two nodes ) of not more than 28 minutes ( or 58 minutes), have later reach including the return journey time one hour ( or two hours) connections in a transfer hubs ( Bustreffpunkt, end of the line ) to be able to. An orbital period of 40 minutes, for example, leads to long pause times at endpoints (often five to eight minutes) added to the transfer times at venues. It causes almost the same time-dependent costs, such as a ride of 58 minutes. Therefore, line paths are often shortened or lengthened to introduce a basic interval timetable.

The SBB (Swiss Federal Railways ), the travel times between nodes adapted by construction that they are each at a half or a full clock period at half-hour intervals. Thus, the paths intersect at every half and full hour in a node and there are optimal transfer connections. On most lines, there is now a 30 -minute intervals. However, there is on single-track lines in part only in the public timetable purely a 60-60 minute intervals. In the operational timetables, however, a 58- 62- minute intervals is sometimes realized when some intersections can be carried out asymmetrically.

Due to the regionalization are in Germany " ITF islands" emerged, with Germany far the fixed symmetry minutes (58 ½) is applied. Problems are particularly at transition regions between the federal states ( for example, in Osnabrück). In order to establish a valid nationwide in Germany basic interval timetable for regional services, has established the " Germany - clock " initiative on April 7, 2008. This would open up a technical discussion on a conceptually better public transport in Germany and identify areas for improvement.

The Federal Association of rail transport and the German Bahn AG intends to examine the feasibility of a basic interval timetable in Germany (so-called Germany - clock ) as part of a feasibility study (July 2010). On 13 September 2011, the inaugural meeting of the steering committee was held to consider proposals for a Germany - clock. The Federal Department of Transportation wrote in April 2013 from a feasibility study for a Germany clock in rail traffic.

Emergence integral clock schedules

Transport Technical and political- economic targets

The following questions are at the beginning of a schedule design:

• Which line has the highest priority?
• Which line is the shortest residence time in the station have?
• What operations must be guaranteed ( political restrictions )?
• From which starting point ( station ) of the roadmap is to be expected?

Thus, for example, needs the train from Zurich to Bern not connected to the return to Zurich to have. A train of Emden needs in Bremen no connection to a local train to Osnabrück to have when there previously in Oldenburg a direct connection there. Here, however, be neglected connections to transit stops, for example Diepholz ( in the timetable 2007/ 08 therefore has the connecting flight Emden - Diepholz a waiting time of 61 minutes in Bremen - the previous connection is missed ).

The residence time of the long-distance trains (ICE, EC, IC) should be as short as possible, but must transfer times between the trains when the transition is intentional, be sufficient. On the schedule stability, has also effect which delays are to be awaited ( waiting period requirement ). Single-track sections and the predetermined thereby Zugkreuzungsmöglichkeiten affect the timetable in particular. Therefore, continuous double-track lines are much easier to vertakten.

Clock nodes, time symmetry and meaningful networking

Aspects of availability, in addition to a slight memorability of travel times optimized connections. Hallmarks of a basic interval timetable is that cheap Umsteigeanschlüsse between as many intersecting lines exist at the network nodes ( clock nodes ).

A clock node is a station for the prompt, there is a transfer possibility on other timing features. A distinction is made between full node, in which relatives trains in pairs with each corresponding connection, and half node where this is true only with restrictions.

• Full nodes are usually large cities with a central station ( Hauptbahnhof), situated where several lines simultaneously. The maximum clock density is mainly determined by the Mindestzugfolgezeit there (eg in block distance ) and by the maximum number of assignable tracks. Traffic minutes and sequences are then determined from the travel times to adjacent major node. The transfer times are each node separately to note and as short as possible ( change trains on the same platform). Full hub stations in Switzerland include Berne, Zurich HB and Basel SBB. In the DB, among others, Cologne and Munich earlier also.
• Half nodes are stations where only a part of the trains have mutually port. Mostly this follows from traveling due to time constraints, based on different distances full and others half knots.

The intersection points of a single-track railway line are determined by the existing passing places. For multiple-track crossing routes or nodes can be arbitrarily set. By defining a node, however, all crossings ( points of symmetry ) are set a Zuglaufweges. Changes of these points can only be additional delays or stops operations and travel time changes are made (eg, skipping breakpoints ).

Only same symmetry times of all intersecting at a transfer hubs lines give equal transit times in both directions. This is a prerequisite for a high acceptance of connecting flights with passengers. However, short transfer times are only possible if a transfer point is symmetry nodes of a route at the same time. If two major transfer hubs but too close together or too far apart, they can not simultaneously be symmetry node ( the distance must be at an hour about 20 to 26 minutes driving time). In this case arise scheduled connection losses or long connection times, which can be avoided, at best, in the sense of a half- node for the more important of the possible Umsteigerelationen. This problem is especially true for the regional public transport where thus be due to low demand and low public transport share the intervals usually 1-2 hours and the node distances 30-60 minutes or about 20-50 km, during one of the residential structure adapted Subway usually has a mesh size of 5-10 km would. To allow a small-scale basic interval timetable with short interval, and a dense network of symmetry node is the goal of rural people mover system point path.

For improving connection times the crossing points of the respective lines can be moved in single lines, however, this is often not possible. Another possibility is to include time- varying passenger flows. By clock shifts to morning or afternoon rush hours exactly certain connections can be improved at the expense of other relations. This approach requires a consideration of the respective transport network as a system with multiple dependencies.

In practice, nodes of transport lines are determined regionally in Germany. As an example, a railway line from Osnabrueck to Bremen her main node in Bremen, a line Osnabrück -Münster in Münster, Westphalia ( NRW as part of the clock ). Since the travel times (36 and 73 minutes) of these two lines do not permit a simultaneous symmetry nodes in Osnabruck, where it meets the RE from Bremen one minute after the scheduled departure of the regional train to Münster. This is an extreme example of a connection loss due to unfavorable travel times (not matched to the ITF infrastructure), but also a lack of coordination between the timetables of different German federal states. A solution to this problem could lie in the continuous operation.

In a basic interval timetable is global for all involved lines of symmetry a fixed time. For simplicity, one goes in theory most of the minute: from 00 (zero symmetry). In practice, however, the symmetry is minute in German-speaking and partly also in other European countries by international agreement 1.5 minutes ago: 00 In order for a departure to the half or full hour is sought at the nodes. In Germany they first came to the introduction of the clock hours in the intercity network in 1979 at minute 57, but was later changed to the majority of the routes to 58.5. The Switzerland took over in 1982 the first German " axis of symmetry " she later changed but also. From the beginning, there was the case of cross -border train routings the problem is that the symmetry times of adjacent countries do not always coincide. The Netherlands in particular, who had introduced the first comprehensive clock schedule until December 2006, a symmetry minute to the quarter hour had.

Prerequisite for the establishment of a basic interval timetable is a well-connected transport system. This concerns first of all the sensible merging of short single lines to longer regional routes from city to city or from region to region. In short Eilzuglinien Germany were merged with the introduction of RE- trains - as was at that time, for example, a "NRW - Express" continuously from Aachen to Bielefeld. As a second point lines can not be reduced to the extent that only a feeder function to a change junctions remains as a pure pre-accession or collection function requires no integrals schedule. Branch lines should therefore achieve a change junctions in both directions and not dull away in the country. Developments in recent years, however, stand in the way, and in the regional bus services.

Mathematical Foundations

A moving train line to meet the other trains in the same line double clock frequency, eg cross at a clock in each direction every hour traffic, the trains along the route every half hour. Such opportunities exist for the establishment of an Integral Umsteigeknotens. In reality, this is not always implemented as usually too many to link lines are involved. In practice, the first full nodes are calculated, where the first long-distance trains to get an acceptable clock and then the local trains are aimed. (Even if one of the lines only runs every two hours, here are to rule optimal connections. ) The half- nodes are then in smaller, adjacent interchanges.

Integration of the public traffic

So far, the rail traffic was mainly treated as here in the use of infrastructure exclusivity by only one mode of transport available. The implementation of related schedules at tram and bus lines becomes very much more difficult, because the intensity of the road mitnutzenden individual traffic fluctuates. Nevertheless, there are successful examples of a basic interval timetable in regional bus services, for example in the district of Rügen, and in urban areas. Nevertheless, a noticeable timetable and connections to the rides are desirable, which is not always bring into harmony. As a remedy, particularly in large cities serve as measures acceleration lanes or independent body to track tram ( also buses available ).

To realize is easier to pre- railway passengers from the urban transport to a central station ( or pick-up from train station). Here, only the connection times by train are to be optimized to road passenger transport; So there will be no integral schedule that takes into account all modes of relationships. Good conditions offer this central stations ( eg bus stations ) near the station, a more difficult situation exists in cities with major transfer hubs in the downtown area, the train station to the second transfer hubs is. The schedules must also in this case at arrival, departure and cycle times of regional rail services oriented (possibly also long-distance services ).

In Switzerland, operate according to the principle of universal clock transport and postal cars and public transport (tram, bus) national coverage of the clock.

Reference point of an interval timetable and Bezugslaufweg

Numerous public representations silent about it, within what periods a clock schedule applies. The time require for the purpose of validity but also a geographic location. Precise statements thus require a high theoretical effort. In Switzerland, the clock schedule applies in principle from the start of operation until closing, where the densities are common in the off-peak hours and in peripheral thinning or in the peak periods. For evening and weekend traffic which traffic minutes usually correspond to those of the daily traffic during the week.

During the whole period of validity of a clock movement find intersections of rides one and the same line always in the same places instead. ( In the initial screen of Euskirchen station for each line involved is such a place. ) For the purpose of formal descriptions are candidates for such sites ( arbitrarily chosen ) reference points.

Example

Daily valid statement. The 11 December 2005. Without guarantee. The Intercity Express Line 12 of the DB runs every two hours, of which at Bezugslaufweg Frankfurt (Main) < > Karlsruhe with nine pairs of trains daily, and visitors will meet yourself in the (imaginary) reference point south of Frankfurt to the odd full hours 07 09 11 13 15 17 19 21 23 clock.

The extension runs in Bezugslaufweg Berlin Berlin < > Karlsruhe with seven pairs of trains daily, and visitors will meet yourself in the (imaginary) reference point south of Göttingen to the odd full hours 09 11 13 15 17 19 21 clock.

Reinforcements from other lines and not daily trips and other sequels this line Basel / Interlaken play no role for this statement; Main thing is that trains arrive on time in a Bezugslaufweg.

Another example is the ICE line 11, whose trains run every two hours between Göttingen and Berlin, with seven pairs of trains daily. The trains meet in Braunschweig Hauptbahnhof each for 58 minutes Example: 12:58 ICE 692 München Hbf to Berlin from Ostbf. <> 12:58 ICE 599 from Berlin Ostbf. to Munich Hbf

Time -distance diagram

A ( this, sufficiently coarse ) time -distance diagram ( jargon: Image timetable ) shows the operation of the line over the entire day is ( the lines are fictitious and Zurich and Chur hours node, Sargans is a half-hour knots):

Demarcation

The Bezugslaufweg must be a part of the path of the line; for example, every second ride or otherwise single journeys on the usual turnarounds addition can be made. The equality of Bezugslaufweg and path is the most common special case.

The reference point for the purpose of illustrative description should be on the Bezugslaufweg whose endpoints included. If it is on an endpoint, so this describes the local twist ( special case of the intersection, and the tacking drive encounters " themselves"). If the reference point between the endpoints, it is assigned to a road junction taking place. This can be done at a bus stop or on the open road. In the latter case one uses to describe a sufficiently close station with designated schedule times. This leads to expressions such as " close to ", " shortly after " or simply " against" that are accurate enough for the purpose of spontaneous access.

With multiple points of intersection of the line, a candidate should be selected so that so can describe the largest possible part of the clock schedule. When the clock traffic, in both directions of the same number rides, then there are ( as in the example ) is exactly optimal availability statement. In many cases, in contrast, can not be detected at the same time all the rides, so excerpts have to serve.

Also reference points can be specified out of focus, for example, if day or week time-dependent travel speeds are different, so that the "points" movable and strictly speaking sections are ( blur in computer science ).

Definition

A reference point is a point on the ( undirected ) Bezugslaufweg an existing clock traffic in both directions of a line of public transport. With a suitable choice describes the tuple (line, Bezugslaufweg, reference point, traffic days, cycle length, interval) in a compact manner the validity period of the clock roadmap and thus fairly reliable indicator of the availability of transport.

The above examples as a 6- tuple read then

Significant Roadmap extract

Essential components of simplification, since the avoidance of the appearance of amplifier drives and the expulsion of the only ( eg, daily valid) basic clock. In Switzerland, the data refer to the period from Monday to Friday 8-20 clock on a schedule box or a clock node. Due to the shorter walking distances than in Germany (less Travelled - crossings) and the distribution of walking distances in timetable fields no such complex explanation is required. The statements in advertisements are always related to the main node, and the compression trains, which are not offered continuously during this time are omitted.

Waiver of a clock schedule

The French State Railways ( SNCF) directs its schedule in the long-distance transport of mainly due to the load directions and passenger flows. So Friday night run many trains from Paris to the regions, on Sunday evenings reversed many trains to Paris. In return, some double track lines are operated in the way working, so that simultaneously operate on both tracks, the trains in the same direction to increase the train density in this direction. This channeling (French canaliser, steer in a certain direction ') has the disadvantage that no trains in the opposite direction are possible; However, in the suburban area of Paris, this operational disadvantage are more easily resolved due to the third and fourth tracks. But France is gradually on the path to a network-wide clock schedule: Alone the timetable change on 11 December 2011, the proportion of the clock paths in the national rail network of RFF was doubled from a total of 8 % to 16 %. Here, however, it should be noted that these trains usually with different final destinations. For the SNCF tried long-distance transport daily umsteigsfreie - ie offer a direct connection between the various regional centers.

In the Italian State Railways ( FS) there is on most routes during the day a so-called maintenance window; during this time may no trains over a certain section, to allow time for maintenance. However, some long-distance and regional lines are already harmonized with, particularly in the suburban railway traffic of large cities, and generally in northern Italy.

History

Integral clock schedules were initially developed for the railway. The idea for a clock schedule was first demonstrated in 1909 A new high-speed rail system from the Publisher August Scherl in his book. With a close-knit rail network with rail and bus connections he wanted to establish a transport network with short transition times. Periodic sequence of moves with equidistant nodes, simultaneous arrival of the trains on the main secondary and tertiary routes should ensure with short transition times, a high overall travel speed. Electrified commuter trains with 200 km / h should take as a monorail with gyro stabilization on the main routes. Scherl separated the passenger and goods traffic.

Outside of urban railways, the clock schedule first came from 1939 on the railway network of the Netherlands for use.

Early as 1940 drew John Frederick Pownall a basic interval timetable for the South of England: He divided the secondary road network in 80 km long sections with edge times of fast trains of 50 minutes ( without stops ) and regional trains, each 1 hour 45 minutes; emanating from London main routes had been deliberately taken the proposal. Pownall also provided for the establishment of new lines short, if this was necessary to achieve these generally defined edges hours between two clock nodes. In the main railway stations the platforms should be arranged so that the express trains stop behind the other on either side of a wide central platform for 10 minutes and end the regional trains on the tongue platforms in the midst of fast trains or start.

1949 August Roesener hit for the network of the German Railways a rigid timetable for the long-distance transport before. In the final state, a four -hour intervals for Eilzugläufe should occur in the network, which should be with the lowest possible interchanges linked to many nodes.

Once on a Swiss route in 1968 the half hour was introduced as a rigid timetable with success, made ​​further developments in the Netherlands. Here the Nederlandse Spoorwegen 1970/71 led under the name " Spoorslag '70 " a node a timetable. In the Federal Republic of Germany the intercity network was in 1979 for the first time on a large scale a clock schedule basis, which offered a hourly long-distance transport. In Switzerland, an area-wide integral interval timetable according to the idea of the project group " Spinner Club" was introduced to Samuel Stähli in May 1982, the - came to be applied to all rail lines and also postal routes ( intercity buses ) - up to a few excursion railways and branch lines. The basic clock was a train per hour. "We're going with clock - Your SBB " was once the slogan of the SBB. To a large timetable change a phonogram published with songs and instrumental melodies for clock schedule. Then were heard, inter alia Nöggi, Edi Bear and Beny Rehmann. This system has been improved every two years. The development ended with the 1985 for the time being presented and decided in late 1987 Rail 2000 program of the Swiss Federal Railways ( SBB), which provided a link of all the centers of the Swiss plateau in the express trains every hour.

"Every hour, every class " was the slogan of the 1979 introduction of the IC -79- system of the DB. This was accompanied by the introduction of a synchronized timetable in the German long-distance railway. Most German states have introduced integrals clock schedules for the rail transport with a two- hour or hourly intervals since the mid- 1990s.

In Germany the first initiatives for the introduction of a basic interval timetable of the states of Bavaria, Baden- Württemberg and Rhineland -Palatinate went out. The early 1990s, Germany's Federal Ministry of Transport, the German Transport Forum and the German Federal Railroad together studies on the feasibility of an ITF in southwest Germany. Due to the size of the regional transport network of former Federal Railway, and the associated scope of planning, the concept should be introduced first in a subspace. Conurbations should thereby be excluded because of the transport had previously been modernized and rationalized there. The Southwest was selected after the affected states of Bavaria, Baden- Württemberg and Rhineland -Palatinate had the planning is significantly supported and co-financed.

The pilot project was referred to as integral timetable south-west. In addition, was reorganized with the introduction of ICE traffic to and from Hamburg in 1991, the regional rail passenger transport in Schleswig -Holstein to the clock node Husum and Lübeck around. As a first integral timetable in Germany Allgäu - Schwaben- clock was introduced in 1993.

In 1993, the Land of Thuringia a study on the nationwide introduction of an ITF in order. In 1995, Thuringia, a precursor of an ITF, 1995 and 1997 was followed by ITF precursors in the area of the Rhine -Main Transport Association, 1996 Mecklenburg -Vorpommern and Saxony -Anhalt and North Rhine- Westphalia in 1998. Most of the other states followed with precursors and conceptual planning until 2001.

At the regional level clock schedules with a base clock of 20 or 30 minutes are available in transport associations often, which is compressed by line overlay on 10 or 5 or 15 or 7.5 minutes. In some areas, this includes also the inclusion of the regional bus services (see, for example, clock in Regio NRW and some areas of Lower Saxony ).

June 2, 2002, a clock schedule was introduced also in the Finnish long-distance railway.

Criticism

• Malfunctions can build up in a highly vertakteten schedule. This can be counteracted by suitable provision as the provision of MRP trains.
• In a rigid clock schedule a connection is either regularly or not offered, with a lag, there is no alternative to unfavorable Connecting.
• For older or mobility-impaired passengers, the terminal times are measured in part to short, a miss of transport leads to long waiting times.
• Short transfer times of just a few minutes at a necessary platform changes require a high orientation ability. This can result in occasional public transport -using passengers stress and uncertainty mean.
• After the nationwide power failure of 22 June 2005 the question was raised in Switzerland, whether driven by the standard local precision clock schedule does not lead to periodic modulations of electricity consumption and production ( by braking or downhill running trains ), which can no longer compensate for stochastic and therefore require increased power reserves. This theory was disproved later.