e ects of the proposed cable cars system in the ... · pdf filetants are in the remaining 3.5%...

Contemporary Engineering Sciences, Vol. 11, 2018, no. 2, 81 - 91HIKARI Ltd, www.m-hikari.com

https://doi.org/10.12988/ces.2018.712207

Effects of the Proposed Cable Cars System

in the Accessibility of Pereira, Colombia

Luis Gonzalo Velasquez-Villada, Diego Alexander Escobar Garcıa1

Department of Civil EngineeringUniversidad Nacional de Colombia, Sede Manizales, Colombia

Carlos Alberto Moncada Aristizabal

Department of Civil and Agricultural EngineeringUniversidad Nacional de Colombia, Sede Bogota, Colombia

Copyright c© 2018 Luis Gonzalo Velasquez-Villada, Diego Alexander Escobar Garcıa,

and Carlos Alberto Moncada Aristizabal. This article is distributed under the Creative Com-

mons Attribution License, which permits unrestricted use, distribution, and reproduction in

any medium, provided the original work is properly cited.

Abstract

Accessibility studies allow us to see the easiness of connection be-tween the different geographical places in a region, either current orproposed in a new project. City planners propose new infrastructureplans that focus primarily on increasing mobility but they affect acces-sibility. This paper shows the influence that the new cable cars systemwill have in the global accessibility of Pereira (Colombia) and it high-lights the neighborhood Villa Santana. These results were obtainedthrough a geostatistical analysis of the travel time variable and showsthat Villa Santana inhabitants will experience a reduction between 4%and 24% in their travel times.

Keywords: Accessibility analysis, cable cars, geostatistics, fairness.

1 Introduction

Accessibility, defined as the potential for interaction between different geo-graphic locations [1] or ease of access to opportunities [2], implies how a group

1Corresponding author

82 Luis Velasquez, Diego Escobar and Carlos Moncada

of people, considering their own limitations, can be included in the differenturban activities, like jobs, education, recreation, medical services, or others.From the point of view of transport, accessibility becomes a cost distribution[3] represented by distances between areas of interest, or preferably, by traveltimes in the transport network [4]. Integral accessibility is the cost distributionfrom all nodes to a single one [5] and global accessibility is a representation ofall the integral accessibilities in the network within the same graph.

This measure of accessibility, based on the infrastructure and representedby the travel times between each node, does not comply with the theoreticalconcept of accessibility [6] [7], since it does not include the travel choice of eachperson, age, disability, race, among others variables [8] [9]. However, Miller[10] defines that accessibility is directly related to the benefits that transportinfrastructure offers to individuals, therefore these analyses become an easyand quick way to present information on the current or future behavior of thetransport network to city planners [6].

Global accessibility studies, have been presented as a tool in the planningof territory [11] [12]. These studies show the reachability of any node in aregion, given the conditions of the network and taking into account the modeof transport for the analysis [13]. These studies suggest a mitigation of socialexclusion as long as the financial and time cost in the transport network, arethe lowest possible [2].

Geographic information systems (GIS) are an easy-to-use tool that allowsaccessibility studies to be carried out on a transport network and the evaluationof the new infrastructure projects [14]. GIS enable a friendly visualization ofdistances or cost between given nodes [15] [10]. The results are presented withisochrone curves representing the travel times needed to reach an area in thecity.

Most Colombian cities have a mono-centric structure, a great quantity ofjobs and services are concentrated in the same area. The city of Pereira plansto construct a cable cars system (Fig. 1) that connects the city core, the busstation, the Universidad Tegnologica de Pereira (UTP), and the community ofVilla Santana (south east). It is expected that this project will generate moreparticipation of Villa Santana neighbors in the city jobs. Although, a greateraccessibility to the different centers of activity does not imply, in this case, thecreation of more jobs, it is necessary, in search of fairness, facilitate the accessto them [16] [6].

2 Methodology

The development of this article follows the methodology proposed by Miller[10], whose procedure is clearly shown in [17] and [12]; Figure 2 exhibit theprocess followed in this paper. The basis of these analyses is to present, with

Accessibility analysis 83

!

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2.400 0 2.4001.200 Meters

Figure 1: Network of Pereira, proposed cable cars system in green

the help of GIS tools, isochrone curves that symbolize the mean travel timeswith which every node is reached in a transport network from all nodes (globalaccessibility). The speed values assigned to each edge of the network are takenfrom real data, measured with GPS devices in the city of Pereira all alongthe month of February 2017 by the Universidad Tegnologica de Pereira for theCIDT (Centro de Innovacion y Desarrollo Tecnologico) project.

Initially, a GPS data processing was performed in order to calculate theoperational speed in all edges between 5:00 a.m. and 10:00 p.m. on Tuesdays,Wednesdays and Thursdays of February. Using the equation 1, where vai repre-sents the operational speed i of the edge a in km/h, la the edge length and t thetime when the start and end node of the edge is reached; the operational speedwas computed as the mean of the n speeds calculated, as shown in equation 2.

vai = 3.6 ∗ lat2 − t1

(1)

va =

∑ni=1 v

ai

n(2)


Start

Data CollectionNodes coordinates,edges speeds, inhab-itants information

data

com-

plete

and

verified

Calculation ofspeed and traveltime variables

Accessibility analisys

from one node to asingle one (Relative)

shortest pathscalculation

from all nodes to asingle one (Integral)

geostatistics (spa-tial correlation)

between allpairs (Global) Data validation

Results

end

No

Yes

1

Figure 2: Accessibility analysis flowchart

Once the travel times were obtained, based on the edges operational speedscomputed with equation 2 and the edge lengths, the structure of the roadnetwork was implemented in the GIS tool, the calculation of minimum travel


times from each node to every other nodes in the network was performed usinga Dijkstra algorithm [18] [19]. Also, a comparison was made against results ofa new network with some edges representing the cable cars system. The speedassigned to the new edges was 21 km/h 2.

With the purpose of performing a spatial interpolation of the travel timevector (TT) in the urban area of the city, with and without the cable cars sys-tem, the normality, stationarity, which states that the mean of the TT shouldbe constant with respect to the geographical location; and the finite varianceof the TT, was verified [20] [21]. The calculation of spatial interpolation wasperformed by the ordinary Kriging method, the results were corroborated bycross-validation (resemblance between the observed and computed TT) andplotted using a GIS tool.

3 Results

The mean travel times with which each of the nodes can be reached, from everyother, in the current network of the city of Pereira can be seen in (Fig. 3). Theisochrone curves exhibit a behavior that favors the central zone of the city byits own geographical location. The results demonstrate that the community ofVilla Santana, located in the south east of the city, is the zone with the greaterdifficulty of access with travel times between 37 and 50 minutes.

Figure 5(a) shows the relation between the coverage of the isochrone curves,population and area of the city 3. The results indicate that 96.5% of popula-tion (94.5% of urban area) reach their destinations with travel times equal orless than 37 minutes. This results demonstrate that the Villa Santana inhabi-tants are in the remaining 3.5% of the population that experience the greatestdifficulties in accessibility.

When the MEGACABLE (name assigned to the cable cars system) is in-cluded in the transport network of the city, a significant variation is obtainedfor the community of Villa Santana, their travel times change from 37 and 50minutes (without cable cars system) to 32 and 42 minutes (with cable cars sys-tem). These results show a reduction, from 6 to 10 minutes. Figure 4 exhibitthe isochrone curves of these times over the whole city.

2the speed of the cable cars is equal to reported by one of the bid-ders. URL = http://newsroom.doppelmayr.com/es/doppelmayr/prensa/8-seater-gondola-grasjoch-with-world-novelty-2-2-2/

3The distribution of population in the city area was provided by the metropolitan ad-ministration for the CIDT project


2.100 0 2.1001.050 Meters

Ü Value

20

22

25

27

30

32

35

37

40

42

45

47

50

Figure 3: Isochrone curves for the city network without cable cars system,values in minutes

Ü Value

20

22

24

26

28

30

32

34

36

38

40

42

44

2.100 0 2.1001.050 Meters

Figure 4: Isochrone curves for the city network with cable cars system, valuesin minutes


0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20 25 30 35 40 45 50Travel time (min)

Cum

ulat

ive

cove

rage

per

cent

age

Population

Area

(a) Actual situation (without cable cars).

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

20 25 30 35 40 45Travel time (min)

Cum

ulat

ive

cove

rage

per

cent

age

Population

Area

(b) Future situation (with cable cars).

0%

10%

20%

30%

40%

50%

60%

70%

0 2 4 6 8 10 12 14 16 18 20 22 24saving percentage (%)

Cum

ulat

ive

cove

rage

per

cent

age

Population

Area

(c) Travel times savings in percentage with the new cable cars system.

Figure 5: Relation between isochrone curve coverage, population and area.

Carrying out a similar analysis to the one showed in figure 5(a) with respectto the coverage of isochrone curves, the population and area of the city whenthe cable cars system is included in the city network (Fig.5(b)); we can seethat 96.6% of the population (94.8% of the urban area), will be covered bytravel times equal to or less than 36 minutes, so that we can infer a positiveimpact of the new cable cars system in the city.

A comparison between the figures obtained with (Fig. 4) and without thecable cars system (Fig. 3) shows that, in total, the cable cars project willrepresent a saving in travel times between 1 and 2 minutes for 44.7% of thepopulation (44.3% of urban area) and 6 to 10 minutes for 0.76% of the popu-lation (percentage corresponding to the community of Villa Santana). Figure5(c) and figure 6, shows that the cable cars project will produce savings of 2%in the actual travel times of 75% of the population and between 4% and 24%for the Villa Santana neighbors.


Ü

2.400 0 2.4001.200 Meters

Value

0

2

4

6

8

10

12

14

16

18

20

22

24

Figure 6: Isochrone curves of the travel time savings, values in percentage.

4 Conclusion

The cable cars project in the city of Pereira proposes an increase in the accessi-bility as it will reduce the travel times for an extensive part of the population,specially, for the inhabitants of Villa Santana who will benefit the most fromthis intervention. Although, the concept of accessibility here is based on easeof connection between places, a deeper analysis should be carried out assess-ing the individual connection needs, their preferences, and travel choices [22].This suggests moving from place-based to people-based accessibility [23] with-out reject the ability of integral and global accessibility analyses to facilitatethe research of the complex travel choice of inhabitants, considering their desireto reduce the time expended on each displacement; and the easiness to presentto city planners the changes in the accessibility of the city with a given project.The present research should be considered as a part of a deeper analysis inwhich it can be determined what will be the advantages of these inhabitantsto whom his travel time is been reduced.

Acknowledgements. We would like to thank the CIDT, UTP and SIR-IUS group, especially the engineer Orlando Sabogal Cardona, for providingthe data required in this research.


References

[1] W. G. Hansen, How accessibility shapes land use, Journal of the Amer-ican Institute of Planners, 25 (1959), no. 2, 73-76.https://doi.org/10.1080/01944365908978307

[2] J. Preston and F. Raje, Accessibility, mobility and transport-related socialexclusion, Journal of Transport Geography, 15 (2007), 151-160.https://doi.org/10.1016/j.jtrangeo.2006.05.002

[3] M. Batty, Accessibility: in search of a unified theory, Environment andPlanning B: Planning and Design, 36 (2009), 191-194.https://doi.org/10.1068/b3602ed

[4] J. Gutierrez Puebla, Redes, espacio y tiempo, Anales de Geografia de laUniversidad Complutense, 18 (1998), 65-86.

[5] D. R. Ingram, The concept of accessibility: A search for an operationalform, Regional Studies, 5 (1971), no. 2, 101-107.https://doi.org/10.1080/09595237100185131

[6] K. T. Geurs and B. Van Wee, Accessibility evaluation of land-use andtransport strategies: review and research directions, Journal of TransportGeography, 12 (2004), 127-140.https://doi.org/10.1016/j.jtrangeo.2003.10.005

[7] G. Boisjoly and A. M. El-Geneidy, How to get there? a critical assess-ment of accessibility objectives and indicators in metropolitan transporta-tion plans, Transport Policy, 55 (2017), 38-50.https://doi.org/10.1016/j.tranpol.2016.12.011

[8] K. Lucas, Transport and social exclusion: Where are we now?, Trans-port Policy, 20 (2012), 105-113.https://doi.org/10.1016/j.tranpol.2012.01.013

[9] J. M. Morris, P. L. Dumble and M. R. Wigan, Accessibility indicators fortransport planning, Transportation Research Part A: General, 13 (1979),no. 2, 91-109. https://doi.org/10.1016/0191-2607(79)90012-8

[10] H. J. Miller, Measuring space-time accessibility benefits within trans- por-tation networks: Basic theory and computational procedures, Geo- graph-ical Analysis, 31 (1999), no. 1, 1-26.https://doi.org/10.1111/j.1538-4632.1999.tb00408.x


[11] D. A. Escobar Garcıa, F. J. Garcıa Orozco and R. A. Tolosa C., Analisisde accesibilidad territorial a nivel regional, Manizales, Colombia: Uni-versidad Nacional de Colombia. Facultad de Ingenierıa y Arquitectura,Manizales, primera ed., 2013.

[12] D. A. Escobar Garcıa and C. F. Urazan Bonells, Accesibilidad territo-rial: instrumento de planificacion urbana y regional, Revista Tecnura, 18(2014), 231-239.https://doi.org/10.14483/udistrital.jour.tecnura.2014.se1.a18

[13] D. A. Escobar Garcıa and F. J. Garcıa Orozco, Diagnostico de la movilidadurbana de Manizales, Universidad Nacional de Colombia Sede Manizalesprimera ed., 2012.

[14] P. D’Amico, F. D. Martino and S. Sessa, A gis as a decision supportsystem for planning sustainable mobility in a case-study, ContemporaryEngineering Sciences, 5 (2012), no. 1, 9-32.

[15] L. Ramırez, La accesibilidad y la movilidad espacial. posible tratamientomediante sistemas de informacion geografica, Cuaderno de ideas No. 2,2006.

[16] N. Tilahun and Y. Fan, Transit and job accessibility: an empirical study ofaccess to competitive clusters and regional growth strategies for enhancingtransit accessibility, Transport Policy, 33 (2014), 17-25.https://doi.org/10.1016/j.tranpol.2014.02.002

[17] D. A. Escobar Garcıa, C. Cadena Gaitan and A. Salas Montoya, Cober-tura geoespacial de nodos de actividad primaria. analisis de los aportes ala sostenibilidad urbana mediante un estudio de accesibilidad territorial,Revista EIA, 12 (2015), 13-27.

[18] M. M. Masoumi, F. H. Lofti and A. M. Mobasseri, DEA and multi- objec-tive shortest path problem, Contemporary Engineering Sciences, 3 (2010),no. 2, 53-62.

[19] W. Nawaz, K. U. Khan, and Y.-K. Lee, Shortest path analysis for efficienttraversal queries in large networks, Contemporary Engineering Sciences,7 (2014), no. 16, 811-816. https://doi.org/10.12988/ces.2014.4696

[20] R. Giraldo Henao, Introduccion a la Geoestadistica, 1993.

[21] M. A. D. Viera and R. C. Gonzalez, Geoestadıstica Aplicada, 2002.


[22] M.-P. Kwan, Space-time and integral measures of individual accessibil-ity: A comparative analysis using a point-based framework, GeographicalAnalysis, 30 (1998), no. 3, 191-216.https://doi.org/10.1111/j.1538-4632.1998.tb00396.x

[23] H. J. Miller, Place-based versus people-based geographic information sci-ence, Geography Compass, 1 (2007), no. 3, 503-535.https://doi.org/10.1111/j.1749-8198.2007.00025.x

Received: January 11, 2018; Published: February 1, 2018

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