1 About the Delft web
Delft is a metropolis located in the Netherlands, holding a population of 96168. It is spread over an country of 24 sq.km. ( Wikipedia 2009a ) . The Delft University of Technology is the largest proficient university in the Netherlands, with over 15,000 pupils ( Wikipedia 2009b ) . Due to the important pupil population, cycling is an of import manner of conveyance.
Delft is bound by expresswaies on all sides, except the southern, which is delimited by a main road. The hierarchy of roads in Delft is expresswaies, main roads, chief roads, and local roads. The railroad line cuts across the metropolis, running in the north-south way from the Centre of the metropolis. A chief route and a main road are the chief linkages between the two expresswaies on the either side of the railroad line.
2 Transport Problem in Delft
The railroad line go throughing through Delft is a constituent of one of the chief railroad connexions in the Netherlands, linking Rotterdam and The Hague. The bing 2-track railroad line is deficient, and it has been planned to be upgraded to a 4-track line. However, due to miss of infinite to construct another viaduct, and environmental jobs caused by the railroad line, it has been proposed to reconstruct the railroad line in a tunnel. 2020 is envisaged to be a typical twelvemonth while the building is in operation. Therefore, Links 10486, 9873, and 9827 will be blocked for all traffic. Due to the roundabout way which would ensue due to the out of use links, bicyclers and autos would hold to cover with increased travel times. It is anticipated that Mercuriusweg/Abtwoudse Pad or the Ruys de Berenbrouckstraat links would be used in stead of the out of use links ( Chen 2009 ) .
3 Description of Current scenario and Alternate Scenarios
3.1 Description of the Current Situation 2003
Zones 1-7 are the external zones, whereas the remainder of the zones are considered as the internal zones. The internal zones are the primary countries of concern. It has besides been given that in 2003, zones 23, 24, and 25 are still under development and there is no travel demand from and to these zones ( Chen 2009 ) .
3.2 Description of the Zero-Alternative Situation 2020
By 2020, zones 24 and 25 will hold been wholly developed. However, Zone 23 would still non hold been developed. Infrastructure has been upgraded consequently to link zones 24 and 25 with the remainder of the metropolis. Zone 12 remains the highest trip generating and trip pulling internal zone, as does Zone 1 amongst the external zones.
3.3 Description of Future Situation during Construction 2020
Sing the hereafter scenario for the metropolis of Delft in 2020 during the enlargement of the rail line from 2-track to 4-track, it shall be assumed that this undertaking will be in advancement and 2020 will be a typical twelvemonth. It has been given that during the enlargement, Links 10486, 9873, and 9827 will be blocked ( Chen 2009 ) . The trip coevals remains the same as for the zero-alternate scenario for 2020.
4 Modeling for Current Situation 2003
4.1 Trip Coevals
For executing the trip coevals patterning map, the Zonal-based Multiple Regression theoretical account has been employed. It takes into history the additive relationships of the socio-economic features of the families in the zones, which affects the trips produced and attracted for each zone ( Ortuzar and Willumsen 1999 ) .
The undermentioned maps have been used for the trip bring forthing theoretical account in the instance of internal zones:
Pi = 0.3RESIDENTSi + 0.06JOBSi + 0.03RESEARCHi + 0.03EDUCATIONi
Ai = 0.05RESIDENTSi + 0.75JOBSi + 0.3RESEARCHi + 0.3EDUCATIONi
Pi = production of zone I,
Ai = attractive force of zone I,
RESIDENTSi = figure of occupants in zone I,
JOBSi = figure of occupations in zone I,
RESEARCHi = research installation infinite in zone I,
EDUCATIONi = sum of educational services offered in zone I.
Beginning: Chen 2009
For the instance of external zones, the Numberss of trips generated and attracted have been assessed based on the traffic volume counts. These are as indicated in Appendix 1.
For the internal zones, it can be seen that the variable of the figure of occupants populating in each zone is the most dominant one impacting the figure of trips produced. The variables which are most dominant for trip attractive force are figure of occupations, and the research installation infinite in that peculiar zone severally.
Appendix 2 indicates the trip coevals for 2003, including both the internal every bit good as the external zones.
2003 histogram.JPGFigure 4-1: Productions and Attractions for the Current Scenario 2003
It can be seen from the Appendix 2 and figure 4-1, Zone 12 is the largest trip generator and pulling external zone. Zone 1 is the highest trip generating and pulling internal zone.
4.2 Trip Distribution and Modal Split
The Gravity Model has been employed to bring forth the trip distribution theoretical account. This theoretical account is a type of Man-made Model as “it estimates trips for each cell in the matrix without straight utilizing the ascertained trip pattern” ( Ortuzar and Willumsen 1999 p.159 ) . There are three discrepancies for the Gravity Model map, viz. :
- Exponential Function: degree Fahrenheit ( cij ) = exp ( -?cij )
- Power Function: degree Fahrenheit ( cij ) = cij-n
- Combined Function: cnij exp ( -?cij )
Singly constrained versions, in this instance destination-constrained, can be produced by doing Ai equal to 1, i.e.
Ai = 1 and Bj= 1/ ? iDif ( cij )
The Combined Function fluctuation of the Gravity Model is the most superior one, as it is the best tantrum with the existent ascertained values for trip length distributions of autos ( Ortuzar and Willumsen 1999 ) . OmniTRANS performs coincident modal split, for which the gravitation theoretical account can be extended to the “simultaneous gravitation model” which is given by:
Tijv=p.Qi.Xj.Fv ( zijv )
Tijv= Number of trips from zone I to j via manner V
p= Scaling factor
Xj= Column Balancing Factor
Fv ( zijv ) = Distribution map taking into history the willingness to go by manner V given electric resistance omega
Appendix 4 indicates the traffic distribution of autos in Delft. 44566 autos have been distributed. As can be seen in Appendix 5, 8635 bicyclers have been distributed the full web of Delft.
The average split indicates that 83.77 per centum of the traffic is constituted by autos and 16.23 per centum by bikes.
The trip length distribution map for autos can be seen in figure 4-2. This indicates the willingness to go to a certain distance without any imminence, such as congestion. Hence, in this instance the upper limit uncongested distance travelled is 10 kilometer. Similarly, figure 4-3 indicates the trip length distribution for bikes, which experiences its extremum at 3 kilometer.
The trip clip distributions for autos and bikes have been indicated in Figure 4-4 and Figure 4-5 severally. These maps, excessively, follow a similar form as that of the Trip Length Distribution. In the instance of autos and bikes, both, the extremum is of 12 proceedingss.
The average trip distance for bikes is 3.14 kilometer and the average trip clip is 14.22 proceedingss. Similarly, for autos, the average distance is 7.59 kilometer and clip is 11.12 proceedingss.
Intra-zonal auto trips constitute merely approximately 0.57 per centum of the entire figure of trips made by autos, and those made by bikes constitute about 16.55 per centum of the entire figure of bike trips.
4.3 Traffic Assignment
18.104.22.168 Assignment for Cars
The General Equilibrium technique of traffic assignment has been used for autos. The status as given by Wardrop is that “Under equilibrium conditions, traffic arranges itself in congested webs in such a manner that no single trip shaper can cut down his way costs by exchanging routes” ( Ortuzar and Willumsen 1999 p.303 ) . Under this traffic assignment theoretical account, costs are all perceived in the same manner by the trip shapers, and therefore Stochastic effects are non considered.
The following links have the largest traffic flow ( for a individual way ) of about 7064 autos assigned: 10972, 10973, 11289, 11427, 11428, and 11477. Figure 4-6 represents the traffic assignment for autos in 2003. The colors of the sets, in the graph, indicate the V/C Ratio and the breadth indicates the traffic burden. It reflects that the chief route, the E and west expresswaies traversing the railroad are enduring from V/C ratios greater than 1, which requires attending.
22.214.171.124 Assignment for Bicycles
The Stochastic Method has been employed for the traffic assignment theoretical account for bikes. This method is superior to the All-Or-Nothing Method, as it takes into history the diverseness in the route users ‘ perceptual experiences of distance, travel clip, generalized costs ; and therefore considers alternate paths to the best-route pick, given by the All-Or-Nothing technique. This is a suited theoretical account for the traffic assignment of bikes as this technique does non take into history the congestion effects, which is non calculable since capacities for bikes are non specified.
Link 10850 has been assigned the maximal figure of bike trips for a individual way, which is 941 trips. Figure 4-7 represents the assignment of bikes in 2003. Most of the trips are confined to the internal zones.
5 Modeling for Future Situation 2020
The modeling phases for the future scenarios of 2020 will stay the same till the Traffic Assignment Stage, which would differ based on the out of use links for the future building scenario of 2020.
5.1 Trip Coevals
The Zonal-based Multiple Regression theoretical account has been employed. The maps are the same as those for 2003. However, prognosiss for the figure of occupants, occupations, and the research installation infinite and instruction edifice infinite in 2020 are different from the current twelvemonth. Besides, it has been given that the productions and attractive forces generated by the external zones is to be assumed to turn by 15 per centum from 2020 to 2003 ( Chen 2009 ) .
The above figure 5-1 illustrates that Zone 1 still remains the highest trip production and attractive force external zone ; and Zone 12 continues to stay the highest trip bring forthing and pulling internal zone. The same is reflected through Appendix 3.
5.2 Trip Distribution and Modal Split
The Gravity Model has been employed for the trip distribution. A sum of about 54380 autos have been distributed, and about 10413 bikes. The average split for 2020 demonstrates that about 83.5 per centum of the trips would be by autos, and the staying 16.5 per centum by bikes. For autos, the intra-zonal trips constitute about 0.54 per centum, whereas for the bikes, intra-zonal trips constitute about 15.71 per centum of the trips.
Trip length distribution map ( indicated in Figure 5-2 and 5-3 ) and the trip clip distribution maps ( indicated in Figure 5-4 and 5-5 ) have been generated. The maximal uncongested distance remains the same for both autos and bikes, as in 2003, as besides the upper limit uncongested clip in the instance for autos. For bikes, the maximal clip has reduced to 8 proceedingss.
The average trip distance for bikes is 3.26 kilometer and the average clip is 14.75 proceedingss. Similarly, for autos, the average distance is 7.56 kilometer and clip is 11 proceedingss.
5.3 Traffic Assignment for Zero-Alternative Situation
5.3.1 Traffic Assignment for Cars
The General Equilibrium theoretical account has been employed. The following links have the maximal Numberss of autos assigned, i.e. about 8346 autos, to them for one way: Links 10972, 10973, 11289, 11427, 11428, 11477, and 11478. Figure 5-6 represents the assignment for autos. The colors of the sets, in the graph, indicate the V/C Ratio and the breadth indicates the burden of traffic. The expresswaies continue to hold high V/C ratios, every bit good as the chief roads traversing the railroad.
5.3.2 Traffic Assignment for Bicycles
For the traffic assignment patterning for bikes, the Stochastic Method has been used once more. Associate 10850 has been assigned the maximal figure of bike trips ( 114 trips ) . Figure 5-7 represents the bike assignment.
5.4 Traffic Assignment for Future Construction Situation
In the future state of affairs during building, the determination to upgrade the railroads from two paths to four paths has been made. This would ensue in the shutting of Links 9827, 9873, and 10486.
5.4.1 Traffic Assignment for Cars
It has been calculated that links 11283, 11407, 11463, and 11464 have the maximal burden, of 10723 autos in one way. Figure 5-8 represents the auto assignment sing future building. The cross-railway nexus South of zone 17 experiences a greater burden, whereby there is a decrease in the northern cross-link.
5.4.2 Traffic Assignment for Bicycles
The Stochastic theoretical account employed for delegating the bike traffic that Link 10452 the maximal burden, in one way, of 1446.54 bikes. Figure 5-9 represents the assignment for bikes.
6.1 Trip Coevals
Amongst the internal zones, which are of primary concern, Zone 12 is the zone which remains the highest trip bring forthing and pulling zone. This is supported by the fact that Zone 12 has the highest figure of occupants populating in it, and the maximal figure of occupations bing in this zone. This zone is located at the bosom of the metropolis, next to the railroad line and the chief route linking the two expresswaies. All the internal zones have experienced a growing rate for the figure of trips generated and produced by about 11 per centum.
Zone 1 besides remains the highest trip bring forthing and pulling external zone. This may be accounted by the fact that Zone 1 is straight connected to Delft by the railroad line, and therefore could possibly be an of import junction or location.
6.2 Trip Distribution and Modal Split
The trip distribution can be reflected through the survey of the matrices given in Appendix 4 to 7. For 2003, the maximal figure of auto trips has been of the nature Internal-to-External, with the most dominant one being from Zone 15 to Zone 1. This has non changed for 2020. For 2003 and 2020, the most dominant character of bike trips is Internal-to-Internal, with maximal trips being made within Zone 12. This is every bit should be expected, since long distance travel by bikes is non likely to be made except in rare fortunes. The maximal figure of bike trips may besides be attributed to the fact that Zone 12 is the Delft City Centre. The maximal growing ( 4.8 times ) for auto trips has been seen for the brace Zone 7-Zone 1, and the upper limit for bikes ( 0.15 times ) has been for the brace Zone 5-Zone 12.
On analyzing the zone-to-zone mean travel distance and clip, it can be seen from Appendix 8 and 9 that the maximal addition for trip distance has been from zone 7 to 15 ( 46.86 per centum ) and maximal addition in clip has been for the brace zone 18 to 22 ( 48.67 per centum ) . The maximal addition ( 48.78 per centum ) in cost has been experienced for zone 11 to 22.
The average split indicates a fringy alteration from 2003 to 2005, whereby there is a lessening from about 83.77 to 83.5 per centum for autos. Intra-zonal trips made in 2020 have experienced a autumn from 2003. This may bespeak greater travel distances and clip, and therefore greater generalised costs in the hereafter.
6.3 Traffic Assignment
On comparing the figures bespeaking the traffic assignments for the three scenarios, it can be seen that the maximal auto trips burden remains on the expresswaies specifying Delft on the eastern and western sides. The chief difference can be seen between the zero-alternative and building state of affairs for 2020.
Due to the out of use links, auto traffic has been assigned to the links 1164, 11645, and Westvest-Hooikade peculiarly have experienced a important addition, whereas the Westlandseweg links have experienced a lessening in the burden of trips. Besides, as was expected, there was an increased usage of the Ruys-de-Berenbrouckstraat, and Abtwoudse links. However, the Mercuriusweg saw a lessening in the traffic burden as compared to the zero-alternative scenario, which goes against as was anticipated. In the instance of assigned bike trips, due to the out of use links, the Hof-van-Delftlaan nexus has seen a significant addition in the traffic burden.
The portion of the railroad traversing traffic has been seen to alter for all the three scenarios. This has been indicated in figure 6-1. There is a lessening in the portion from 2003 to the Zero-Alternative scenario. However, comparing the future building scenario with the Zero-Alternative, there has been an addition in the portion, for both autos and bikes.
Zones 1 and 12 being of premier importance, besides supported by their connectivity will go on to rule as the zones pulling and bring forthing the maximal traffic. Since maximal bike traffic burden is concentrated in Zone 12, steps may be taken to curtail the entry of autos in this country so as to guarantee a more safe environment, which would even profit the families, as the maximal per centum are located in this zone. Increased generalized costs must be taken into history, based on the above analysis. Links which are sing greater traffic tonss due to building plants have been identified, and alleviation steps for these should be planned, peculiarly for the expresswaies on the eastern and western side of the metropolis.
8 Strengths and Failings of OmniTRANS
The strength of OmniTRANS is that it helps in the rapid and accurate conveyance mold processs. Besides, the informations can be really easy examined on the conveyance web map, instead than merely being confined to tabular arraies and Numberss, which makes analysis boring. Besides, a figure of variables can be studied, which can be farther sorted out based on the way for any peculiar nexus.
The failings could be cited as merely being able to use the usage of the Simultaneous Gravity Model being available for trip distribution phase. Besides, merely limited types of traffic assignment theoretical accounts can be performed ( such as Stochastic, All-or-Nothing, and Equilibrium ) . Public conveyance modeling is besides non performed by the package ( OmniTRANS 2009 ) .
CHEN, H. 2009. Handout: Coursework Description, talk notes distributed in TRAN5020 Principles of Transport Modelling. University of Leeds, 3 November 2009.
OMNITRANS. 2009. What ‘s New in OT5 [ online ] . [ Accessed on 1st December 2009 ] . Available from hypertext transfer protocol: //www.omnitrans-international.com/resources/brochures/what ‘s % 20new % 202008.pdf.
ORTUZAR, J. & A ; WILLUMSEN, L.G. 1999. Modeling Transport. West Sussex: Wiley.
WIKIPEDIA. 2009a. Delft [ online ] . [ Accessed on 10 November 2009 ] . Available from: hypertext transfer protocol: //en.wikipedia.org/wiki/Delft.
WIKIPEDIA. 2009b. Delft University of Technology [ online ] . [ Accessed on 10 November 2009 ] . Available from: hypertext transfer protocol: //en.wikipedia.org/wiki/Delft_University_of_Technology.