Virtual tourism is a novel trend that enhances the experience the users perceive from touristic places, such as archaeological sites. Drones are equipped with 360o video cameras and used for video capturing of the heritage sites. The video material is streamed to the users in real time, enriched with additional 3D, Augmented Reality (AR) or Mixed Reality (MR) material. Furthermore, the selection of the appropriate flying route for each drone should be performed, in order to provide a satisfactory tour experience to the user, considering his preferences about specific monuments. To address this issue, this paper describes a heritage route selection scheme for supporting real-time virtual tours in sites with cultural interest using drones. The proposed scheme applies a Fuzzy Multiple Attribute Decision Making (FMADM) algorithm, the Trapezoidal Fuzzy Topsis for Heritage Route Selection (TFT-HRS), to accomplish the ranking of the candidate heritage routes. The algorithm uses Interval-Valued Trapezoidal Fuzzy Numbers (IVTFN) for the representation of heritage routes evaluation values. Performance evaluation shows that the suggested method produces better results compared to the Fuzzy Topsis (FTOPSIS) by selecting the most appropriate flying route for the drone.

1. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
A Route Selection Scheme for supporting Virtual
Tours in Sites with Cultural Interest using Drones
Emmanouil Skondras1, Konstantina Siountri1,2,
Angelos Michalas3, Dimitrios D. Vergados1
1Department of Informatics, University of Piraeus, Piraeus, Greece,
Email: {skondras, ksiountri, vergados}@unipi.gr
2Department of Department of Cultural Technology and Communication, University of
Aegean, Mytilene, Lesvos, Greece, Email: ksiountri@aegean.gr
3Department of Informatics Engineering, Technological Educational Institute of Western
Macedonia, Kastoria, Greece, Email: amichalas@kastoria.teiwm.gr
1

2. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Outline
• Introduction.
• Virtual Tours using Drones.
• Multi Attribute Decision Making.
• The Proposed Heritage Route Selection Scheme.
• Simulation Setup.
• Evaluation of the Proposed Scheme.
• Conclusions.
2

3. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Introduction
• Virtual tourism.
– A novel paradigm.
– Reduces time or spatial limitations of real tourism.
– Provides touristic experience to users.
• Modern services construct a totally virtual world for the user.
– 360o video streaming.
– 3D animation.
– Augmented Reality (AR).
– Mixed Reality (MR).
• For example, drones equipped with 360o cameras are used for
the video capture of sites with cultural interest.
– The video material is enriched with 3D, AR or MR material
and streamed to users in real time.
3

4. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Virtual Tours using Drones
• Drones can provide us with real time images.
– With a totally new perspective, the “bird’s eye view”.
• The drone interacts with a Fifth Generation (5G) mobile
architecture.
– Obtains access to plenty of networking, computational and storage resources.
• The 5G architecture could support heterogeneous network access
technologies:
– 3GPP Long Term Evolution Advanced (LTE-A).
– IEEE 802.11p Wireless Access for Vehicular Environment (WAVE).
– IEEE 802.16 WiMAX.
• Thus, enriched 360o video could be streamed to the user.
– Through 5G Mobile Edge Computing (MEC) or Fog infrastructure.
• Assures the satisfaction of its constraints in Quality of Service (QoS) related factors.
– Throughput, delay, jitter and packet loss.
4

5. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Virtual Tours using Drones
• The drone could be remotely controlled or
autonomous navigated.
– A critical task is the selection of the most appropriate
flying route for the drone.
• Specifically, in heritage sites where multiple
monument-types exist:
The user preference for each type should be
considered.
• To select the most appropriate flying route for the drone.
5

6. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Virtual Tours using Drones
• Virtual tours with drones can be used in numerous cases.
– Dealing with protection, preservation and enhancement of tangible heritage.
– Servicing special groups of people.
• E.g. elderly, children, or persons with disabilities that can not reach the
inaccessible monuments.
• Potential uses:
– Emergency.
• Short-time check of the potentially harmed monuments.
– Typical Control.
• Regular control of the heritage sites.
– Shared Experience.
• Real time experience for groups of visitors either by accessing a monument or not.
– Selective Visit.
• Due to time limitations.
– Educational Purpose.
• Holistic experience of the sites including inaccessible spots or monuments.
6

7. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Multi Attribute Decision Making
• Multi Attribute Decision Making (MADM).
– Evaluate different alternatives, sometimes even contradictory, using
multi-criteria analysis.
• Widely used methods include:
– The Simple Additive Weighting (SAW). [lahby2012]
– The Multiplicative Exponent Weighting (MEW). [lahby2012]
– The Gray Relational Analysis (GRA). [lahby2012]
– The Distance to Ideal Alternative (DIA). [lahby2012]
– The Weighted Product Method (WPM). [fitriasari2017]
– The Technique for Order Preference by Similarity to Ideal Solution
(TOPSIS). [kaur2016]
7
[lahby2012] M. Lahby, C. Leghris, and A. Adib, “New multi access selection method based on mahalanobis distance,”
Applied Mathematical Sciences, vol. 6, no. 53-56, pp. 2745–2760, 2012.
[fitriasari2017] N. S. Fitriasari, S. A. Fitriani, and R. A. Sukamto, “Comparison of weighted product method and technique
for order preference by similarity to ideal solution method: Complexity and accuracy,” IEEE International Conference on
Science in Information Technology (ICSITech), pp. 453–458, 2017.
[kaur2016] S. Kaur, S. K. Sehra, and S. S. Sehra, “A framework for software quality model selection using topsis,”, IEEE
International Conference on Recent Trends in Electronics, Information & Communication Technology (RTEICT), 2016.

8. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Multi Attribute Decision Making
• Weighting methods provide suitable criteria weights for each alternative.
– The Analytic Hierarchy Process (AHP) [lahby2012].
– The Analytic Network Process (ANP) [martinez2015].
• There is a rate of uncertainty in evaluating the monuments in each heritage route.
• Fuzzy MADM (FMADM) methods.
– FMADM methods are proposed utilizing linguistic variables, triangular fuzzy numbers,
trapezoidal fuzzy numbers etc.
• To evaluate heritage routes.
• Such methods include the Fuzzy SAW (FSAW) [mohammedfuzzy], the Fuzzy TOPSIS (FTOPSIS)
[devec2017], the Fuzzy MEW (FMEW) [goyal2017] and the the Fuzzy AHP - ELECTRE (FAE) [cha2009].
8
[lahby2012] M. Lahby, C. Leghris, and A. Adib, “New multi access selection method based on mahalanobis distance,” Applied Mathematical
Sciences, vol. 6, no. 53-56, pp. 2745–2760, 2012.
[martinez2015] I. Martinez and V. Ramos, “Netanpi: A network selection mechanism for lte traffic offloading based on the analytic network
process,” 36th IEEE Sarnoff Symposium, pp. 117–122, 2015.
[mohammedfuzzy] D. A. Maroua Drissi, Mohammed Oumsis, “A fuzzy ahp approach to network selection improvement in heterogeneous
wireless networks,” Networked Systems, pp. 169–182.
[devec2017] M. Deveci, N. C¸ . Demirel, and E. Ahmeto˘glu, “Airline new route selection based on interval type-2 fuzzy mcdm: A case study
of new route between turkey-north american region destinations,” Journal of Air Transport Management, vol. 59, pp. 83–99, 2017.
[goyal2017] R. K. Goyal, S. Kaushal, and A. K. Sangaiah, “The utility based nonlinear fuzzy ahp optimization model for network selection in
heterogeneous wireless networks,” Applied Soft Computing, 2017.
[cha2009] D. E. Charilas, O. I. Markaki, J. Psarras, and P. Constantinou, “Application of fuzzy ahp and electre to network selection,” in Mobile
Lightweight Wireless Systems. Springer, 2009, pp. 63–73.

9. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
The Proposed Scheme
9

10. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Simulation Setup
10
• 5G architecture.
– Simulated using the NS3 simulator.
– Includes a Cloud and a Fog
infrastructure.
– A Software Defined Network (SDN)
controller provides centralized control of
the entire architecture.
• Cloud infrastructure
– Includes a set of Virtual Machines
(VMs).
– Each VM hosts a set of 3D, AR and MR
models about monuments.
• Fog infrastructure
– Includes LTE and WiMAX Macrocells
and Femtocells, as well as WAVE RSUs.

11. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Simulation Setup
11
• Monuments inside the area of the Fog:
– Ancient.
• Prehistoric antiquities, monuments of Classical,
Roman and Hellenistic Era and all of their
subcategories.
– Byzantine.
• Antiquities between 330 AD and 1830 AD,
including the subcategories Early Byzantine,
Middle Byzantine and Post Byzantine monuments
(in Western Europe, the term Byzantine could be
replaced by the term Medieval).
– Modern.
• Artifacts after 1830 AD, i.e. exceptional buildings
constructed according to Neoclassic, Art Nouveau
and Bauhaus style, well preserved traditional
complexes, industrial buildings, statues etc.
– Natural Beauty.
• Landscapes with special features, remarkable and
sensitive ecosystems, i.e. rivers, lakes, forests,
canyons, etc.
 The case where 5 users need to perform a
virtual tour using a drone is considered.

12. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
The Proposed Heritage Route Selection
Scheme
• Heritage route selection scheme.
– For supporting real-time virtual tours in sites with
cultural interest using drones.
• Two algorithms:
– Analytic Network Process (ANP).
• Models the user preferences about monument types.
– Trapezoidal Fuzzy Topsis for Heritage Route Selection
(TFT-HRS).
• FMADM algorithm.
Accomplishes the ranking of the candidate flying routes.
12

13. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Model of the User Preferences using
the ANP method2. ANP pairwise comparisons:
13
3. The weights that concern the users'
preferences for each monument
type are estimated.
1. Nine-point importance scale:

14. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
The Trapezoidal Fuzzy Topsis for
Heritage Route Selection (TFT-HRS)
• TFT-HRS adjusts the TFT [skondras2016] algorithm to
accomplish the ranking of candidate heritage routes.
• TFT-HRS concept:
– The best alternative heritage route should have the shortest distance
from the positive ideal solution and the longest distance from the
negative ideal solution.
• The evaluation values of monuments per heritage route are
represented by interval-valued trapezoidal fuzzy numbers.
14
[skondras2016] E. Skondras, A. Sgora, A. Michalas, and D. D. Vergados, “An analytic network process and
trapezoidal interval-valued fuzzy technique for order preference by similarity to ideal solution network access
selection method,” International Journal of Communication Systems, vol. 29, no. 2, pp. 307–329, 2016.

15. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
The Trapezoidal Fuzzy Topsis for
Heritage Route Selection (TFT-HRS)
• The set of possible heritage routes (alternatives):
– AL = {AL1, AL2,…, ALn}
• The set of Monument Types (MT):
– MT = {MT1, MT2,…, MTn}
• The weights (user preferences) for each Monument Type:
– w1, w2, …, wm
• The decision matrix:
 If multiple monuments belong to a specific MT, the decision matrix
includes the average of their gij evaluation values. 15

16. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
The Trapezoidal Fuzzy Topsis for
Heritage Route Selection (TFT-HRS)
• The steps of the method are as follows:
1. Construction of the decision matrix.
2. Construction of the weighted decision matrix.
• Considering the user preferences.
3. Determination of the positive and negative ideal solution.
4. Measurement of the distance of each alternative from the
ideal solutions.
5. Alternatives (heritage routes) ranking.
16

17. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
The evaluation values that each
monument obtains in each route
• The linguistic terms and the corresponding interval-valued trapezoidal fuzzy numbers
used for the definition of the evaluation values of each monument in each flying route.
• Accordingly, the corresponding value that each monument obtains in each route.
– Namely, the Decision Matrix.
17

18. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
The entire process
18

19. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Evaluation of the Proposed Scheme
• The TFT-HRS scheme is compared with the FTOPSIS algorithm.
• A weakness of the FTOPSIS.
– It does not support the existence of multiple monuments of the same
monument type.
– It considers only the first monument of each type, namely the Prehistoric
Monument 1, the Ancient Monument 1, the Byzantine Monument 1 and the
Modern Monument 1, for the Prehistoric, Ancient, Byzantine and Modern
monument types, respectively.
19

20. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Evaluation of the Proposed Scheme
• The TFT-HRS scheme is compared with the FTOPSIS algorithm.
• A weakness of the FTOPSIS.
– It does not support the existence of multiple monuments of the same
monument type.
– It considers only the first monument of each type.
• Namely the Prehistoric Monument 1, the Ancient Monument 1, the Byzantine
Monument 1 and the Modern Monument 1, for the Prehistoric, Ancient, Byzantine
and Modern monument types, respectively.
20

21. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Evaluation of the Proposed Scheme
• The following table compares the results of the proposed scheme with the
ones obtained using the FTOPSIS algorithm.
• TFT-HRS outperforms the FTOPSIS.
– By selecting more appropriate heritage routes considering the evaluation
values for multiple monuments of the same type that exist in each route.
21

22. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Evaluation of the Proposed Scheme
• The following table compares the results of the proposed scheme with the
ones obtained using the FTOPSIS algorithm.
• TFT-HRS outperforms the FTOPSIS.
22

23. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Evaluation of the Proposed Scheme
• The following table compares the results of the proposed scheme with the
ones obtained using the FTOPSIS algorithm.
• TFT-HRS outperforms the FTOPSIS.
23

24. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Evaluation of the Proposed Scheme
• The following table compares the results of the proposed scheme with the
ones obtained using the FTOPSIS algorithm.
• TFT-HRS outperforms the FTOPSIS.
24

25. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
Conclusions
• TFT-HRS.
– Selection of flying routes to support virtual tours in sites with cultural interest
using drones.
• The scheme selects the most appropriate route for the drone.
– In order the user preferences about specific monument types to be satisfied.
• The drone:
– Flights along the selected route.
– Captures video about the corresponding monuments.
• The video is transmitted to the user in real time.
– Enriched with 3D, AR and MR material.
• The scheme applied to a 5G architecture.
• Performance evaluation showed that the proposed scheme outperforms
the FTOPSIS algorithm.
– Since it selects the most appropriate flying route for the drone considering the
user’s preferences about each monument type.
25

26. The 9th International Conference on Information, Intelligence, Systems and Applications (IISA 2018)
26