{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:58:43Z","timestamp":1760144323641,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2024,4,10]],"date-time":"2024-04-10T00:00:00Z","timestamp":1712707200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund (ERDF) within the Regional Operational Program \u201cAttica\u201d under the call \u201cResearch and Innovation Synergies in the Region of Attica\u201d","award":["Project code: ATTP4-0353772"],"award-info":[{"award-number":["Project code: ATTP4-0353772"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper introduces a new routing and touring service both for outdoor and indoor places of touristic and cultural interest designed to be used in the wider area of Attica, Greece. This service is the result of the work performed in OPTORER (OPTORER: OPtimal rouTing and explOration of touRistic and cultural arEas of interest within Attica given personalized adaptive preferences, promoted underlying purpose, and interactive experience), project, and it aspires to offer a range of innovative and thematic routes to several specified points of interest in the selected area of Attica, encouraging the combination of indoor and outdoor routes in a single tour. The aim is to optimize the user experience while promoting specific, user-centric features, with safety and social welfare being a priority for every designed tour, resulting in enhancing the touristic experience in the area. Using a common smartphone device, as well as common wearable devices (i.e., smartwatches), the OPTORER service will provide an end-to-end solution by developing the algorithms and end-user applications, together with an orchestration platform responsible for managing, operating, and executing the service that produces and presents to the end user results derived from solving dynamically complex optimization problems.<\/jats:p>","DOI":"10.3390\/s24082431","type":"journal-article","created":{"date-parts":[[2024,4,10]],"date-time":"2024-04-10T10:55:28Z","timestamp":1712746528000},"page":"2431","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["OPTORER: A Dynamic Routing and Touring Service for Indoors and Outdoor Tours"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6669-4648","authenticated-orcid":false,"given":"Constantinos","family":"Vassilakis","sequence":"first","affiliation":[{"name":"Department of Electrical and Electronics Engineering, Campus of Ancient Olive Grove, University of West Attica, 122 41 Egaleo, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2007-4782","authenticated-orcid":false,"given":"Maria","family":"Polychronaki","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronics Engineering, Campus of Ancient Olive Grove, University of West Attica, 122 41 Egaleo, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dimosthenis","family":"Margaritis","sequence":"additional","affiliation":[{"name":"Department of Industrial Design and Production Engineering, Campus of Ancient Olive Grove, University of West Attica, 122 41 Egaleo, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8985-6136","authenticated-orcid":false,"given":"Dimitrios G.","family":"Kogias","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronics Engineering, Campus of Ancient Olive Grove, University of West Attica, 122 41 Egaleo, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1489-1495","authenticated-orcid":false,"given":"Helen C.","family":"Leligou","sequence":"additional","affiliation":[{"name":"Department of Industrial Design and Production Engineering, Campus of Ancient Olive Grove, University of West Attica, 122 41 Egaleo, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,10]]},"reference":[{"key":"ref_1","unstructured":"(2024, February 04). 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