{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T15:10:58Z","timestamp":1767625858821,"version":"build-2065373602"},"reference-count":55,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2015,6,18]],"date-time":"2015-06-18T00:00:00Z","timestamp":1434585600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In a city there are numerous items, many of them unnoticed but essential; this is the case of the signals. Signals are considered objects with reduced technological interest, but in this paper we prove that making them smart and integrating in the IoT (Internet of Things) could be a relevant contribution to the Smart City. This paper presents the concept of Smart Signal, as a device conscious of its context, with communication skills, able to offer the best message to the user, and as a ubiquitous element that contributes with information to the city. We present the design considerations and a real implementation and validation of the system in one of the most challenging environments that may exist in a city: a tunnel. The main advantages of the Smart Signal are the improvement of the actual functionality of the signal providing new interaction capabilities with users and a new sensory mechanism of the Smart City.<\/jats:p>","DOI":"10.3390\/s150614370","type":"journal-article","created":{"date-parts":[[2015,6,18]],"date-time":"2015-06-18T10:08:36Z","timestamp":1434622116000},"page":"14370-14396","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Managing Emergency Situations in the Smart City:  The Smart Signal"],"prefix":"10.3390","volume":"15","author":[{"given":"\u00c1ngel","family":"Asensio","sequence":"first","affiliation":[{"name":"Arag\u00f3n Institute of Engineering Research (I3A), Universidad Zaragoza, Edificio IDi,  Mariano Esquillor s\/n, Zaragoza 50018, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teresa","family":"Blanco","sequence":"additional","affiliation":[{"name":"Arag\u00f3n Institute of Engineering Research (I3A), Universidad Zaragoza, Edificio IDi,  Mariano Esquillor s\/n, Zaragoza 50018, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rub\u00e9n","family":"Blasco","sequence":"additional","affiliation":[{"name":"Arag\u00f3n Institute of Engineering Research (I3A), Universidad Zaragoza, Edificio IDi,  Mariano Esquillor s\/n, Zaragoza 50018, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7396-7840","authenticated-orcid":false,"given":"\u00c1lvaro","family":"Marco","sequence":"additional","affiliation":[{"name":"Arag\u00f3n Institute of Engineering Research (I3A), Universidad Zaragoza, Edificio IDi,  Mariano Esquillor s\/n, Zaragoza 50018, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roberto","family":"Casas","sequence":"additional","affiliation":[{"name":"Arag\u00f3n Institute of Engineering Research (I3A), Universidad Zaragoza, Edificio IDi,  Mariano Esquillor s\/n, Zaragoza 50018, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,6,18]]},"reference":[{"key":"ref_1","unstructured":"Su\u00e1rez, N. (2009). Se\u00f1alizaci\u00f3n de emergencia en t\u00faneles carreteros y ferroviarios. Obras Urbanas October, 76\u201379."},{"key":"ref_2","unstructured":"Ronchi, E., and Nilsson, D. (2013). Interim Report: Traffic Information Signs, Colour Scheme of Emergency Exit Portals and Acoustic Systems for Road Tunnel Emergency Evacuations, Department of Fire Safety Engineering."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1109\/TPWRD.2012.2212215","article-title":"Remote-Control System of High Efficiency and Intelligent Street Lighting Using a ZigBee Network of Devices and Sensors","volume":"28","author":"Leccese","year":"2013","journal-title":"IEEE Trans. Power Deliv."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"6492","DOI":"10.3390\/s130506492","article-title":"An Easy to Deploy Street Light Control System Based on Wireless Communication and LED Technology","volume":"13","author":"Elejoste","year":"2013","journal-title":"Sensors"},{"key":"ref_5","unstructured":"Minnesota, U. University of Minnesota-Smart Signal. [En l\u00ednea]. Available online: http:\/\/signal.umn.edu\/."},{"key":"ref_6","unstructured":"National Institute for Advanced Transportation Technology (2006). Smart Signals."},{"key":"ref_7","unstructured":"VAISALA VAISALA-Road Solutions. [En l\u00ednea]. Available online: http:\/\/www.vaisala.com\/en\/roads\/Pages\/default.aspx."},{"key":"ref_8","unstructured":"Martin, F.J.L. (2009). Panel Luminoso de Se\u00f1alizaci\u00f3n Vial. (U200901552), Spain Patente."},{"key":"ref_9","unstructured":"Garc\u00eda, M. (2002). Disposici\u00f3n de Emisores \u00d3pticos Y Ac\u00fasticos Aplicable Para la Informaci\u00f3n de Accesos y Salidas de T\u00faneles, Pasos a Nivel Y Similares. (U200200099), Spain Patente."},{"key":"ref_10","unstructured":"(1999). Sistema de Iluminaci\u00f3n Para Se\u00f1ales de Tr\u00e1fico. (P9601957), Patente."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"447","DOI":"10.1016\/j.trf.2007.03.003","article-title":"Effects of route guidance variable message signs (VMS) on driver behaviour","volume":"10","author":"Erke","year":"2007","journal-title":"Transp. Res. Part F: Traffic Psychol. Behav."},{"key":"ref_12","unstructured":"Streitz, N. Smart Future Initiative. [En l\u00ednea]. Available online: http:\/\/www.smart-future.net\/3.html."},{"key":"ref_13","unstructured":"IBM Wellcome to the Smarter City. IBM. [En l\u00ednea]. Available online: http:\/\/www-03.ibm.com\/innovation\/us\/thesmartercity\/index.shtml?cm_mmc=agus_brsmartcity-20090929-usbrb111-_-s-_-genhpmerch-_-sp."},{"key":"ref_14","unstructured":"International Electrotechnical Commission Orchestrating Infrastructure for Sustainable SmartCities. Published in Geneva, Switzerland. Available online: http:\/\/www.iec.ch\/whitepaper\/pdf\/iecWPsmartcities-LR-en.pdf."},{"key":"ref_15","unstructured":"ISO\/IEC Smart Cities: Preliminay Report. Available online: http:\/\/www.iso.org\/iso\/smart_cities_reportjtc1.pdf."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1666","DOI":"10.1109\/JSEN.2010.2045890","article-title":"A Mobile GPRS-Sensors Array for Air Pollution Monitoring","volume":"10","author":"Zualkernan","year":"2010","journal-title":"IEEE Sens. J."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Nasirudin, M.A., Za\u2019bah, U.N., and Sidek, O. (2011, January 25\u201328). Fresh water real-time monitoring system based on Wireless Sensor Network and GSM. Proceedings of the IEEE Conference on Open Systems (ICOS2011), Langkawi, Malaysia.","DOI":"10.1109\/ICOS.2011.6079290"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"9290","DOI":"10.3390\/s140509290","article-title":"A New Acquisition and Imaging System for Environmental Measurements: An Experience on the Italian Cultural Heritage","volume":"14","author":"Leccese","year":"2014","journal-title":"Sensors"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"24408","DOI":"10.3390\/s141224408","article-title":"A Smart City Application: A Fully Controlled Street Lighting Isle Based on Raspberry-Pi Card, a ZigBee Sensor Network and WiMAX","volume":"14","author":"Leccese","year":"2014","journal-title":"Sensors"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1109\/TSG.2012.2219887","article-title":"Smart Personal Sensor Network Control for Energy Saving in DC Grid Powered LED Lighting System","volume":"4","author":"Tan","year":"2013","journal-title":"IEEE Trans. Smart Grid"},{"key":"ref_21","unstructured":"Information Society Technologies Advisory Group (ISTAG) Orientations for EU ICT R&D & Innovation beyond 2013. Available online: http:\/\/cordis.europa.eu\/fp7\/ict\/istag\/documents\/istag_key_recommendations_beyond_2013_full.pdf."},{"key":"ref_22","first-page":"158252:1","article-title":"Protocol and Architecture to Bring Things into Internet of Things","volume":"2014","author":"Gimeno","year":"2014","journal-title":"Int. J. Distrib. Sens. Netw."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Nakashima, H., Aghajan, H., and Augusto, J.C. (2010). Handbook of Ambient Intelligence and Smart Environments, Springer.","DOI":"10.1007\/978-0-387-93808-0"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"B\u00f6hlen, M., and Frei, H. (2010). Ambient Intelligence in the City Overview and New Perspectives. Handb. Ambient Intell. Smart Environ., 911\u2013938.","DOI":"10.1007\/978-0-387-93808-0_34"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1109\/MPRV.2012.58","article-title":"A Smarter Smart Home: Case Studies of Ambient Intelligence","volume":"12","author":"Makonin","year":"2013","journal-title":"Pervasive Comput."},{"key":"ref_26","first-page":"853","article-title":"A New Remote and Automated Control System for the Vineyard Hail Protection Based on ZigBee Sensors, Raspberry-Pi Electronic Card and WiMAX","volume":"3","author":"Cagnetti","year":"2013","journal-title":"J. Agric. Sci. Technol. B"},{"key":"ref_27","unstructured":"Bhuvaneswari, N., Sujatha, S., and Yamuna, R. (2010, January 12). Vibrant Ambient Intelligent System for Traffic Congestion Control in Coimbatore City. Proceedings of the 12th International Conference on Networking, VLSI and Signal Processing (ICNVS'10), Stevens Point, WI, USA."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Cristophe, B. (2011, January 24\u201326). Semantic profiles to model the \u201cWeb of Things. Proceedings of the Seventh International Conference on Semantics, Knowledge and Grids, Beijing, China.","DOI":"10.1109\/SKG.2011.29"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1655","DOI":"10.1016\/j.comcom.2006.12.020","article-title":"Wireless sensor networks: A survey on the state of the art and the 802.15.4 and ZigBee standards","volume":"30","author":"Barontib","year":"2007","journal-title":"Comput. Commun."},{"key":"ref_30","unstructured":"Reite, G. Wireless connectivity for he Internet of Things: One size does not fill all. Available online: http:\/\/www.ti.com.cn\/cn\/lit\/wp\/swry010\/swry010.pdf."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1147\/JRD.2010.2092257","article-title":"Smart cities through standards-based wireless sensor networks","volume":"55","author":"Watteyne","year":"2011","journal-title":"IBM J. Res. Dev."},{"key":"ref_32","unstructured":"Chang, K.-H., and Mason, B. (2012, January 5\u20138). The IEEE 802.15.4g Standard for Smart Metering Utility Networks. Proceedings of the 2012 IEEE Third International Conference on Smart Grid Communications (SmartGridComm), Tainan, Taiwan."},{"key":"ref_33","first-page":"136745:1","article-title":"Hardware Architecture Design for WSN Runtime Extension","volume":"2013","author":"Asensio","year":"2013","journal-title":"Int. J. Distrib. Sens. Netw."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1109\/MCD.2006.1708372","article-title":"Ultra-Low-Power Design: The roadmap to desappearing electronics and ambient intelligence","volume":"22","author":"Rabaey","year":"2006","journal-title":"IEEE Circuits Devices Mag."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Piguet, C. (2004). Low-Power Electronics Desig, CRC Press.","DOI":"10.1201\/9781420036503.ch1"},{"key":"ref_36","unstructured":"Arabi, K. (2004). Low power Design Techniques in Mobile Processors, CRC Press."},{"key":"ref_37","unstructured":"Shearer, F. (2008). Power Management in Mobile Devices, CRC Press."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Ka\u017amierski, T.J., and Beeby, S. (2011). Energy Harvesting Systems: Principles, Modeling and Applications, Springer.","DOI":"10.1007\/978-1-4419-7566-9"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1109\/SURV.2011.060710.00094","article-title":"Energy Harvesting Sensor Nodes: Survey and Implications","volume":"13","author":"Sudevalayam","year":"2011","journal-title":"IEEE Commun. Surv. Tutor."},{"key":"ref_40","first-page":"274","article-title":"An Intelligent and High Efficiency Street Lighting System Isle Based on Raspberry-Pi Card, ZigBee Sensor Network and Photovoltaic Energy","volume":"3","author":"Leccese","year":"2014","journal-title":"Int. J. Eng. Sci. Innov. Technol. (IJESIT)"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Penella-L\u00f3pez, M.T., and Gasulla-Forner, M. (2011). Powering Autonomous Sensors. An Itegral Approach with Focus on Solar and RF Energy Harvesting, Springer.","DOI":"10.1007\/978-94-007-1573-8"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"4424","DOI":"10.1109\/TIE.2010.2102321","article-title":"Energy Harvesting From Hybrid Indoor Ambient Light and Thermal Energy Sources for Enhanced Performance of Wireless Sensor Nodes","volume":"58","author":"Tan","year":"2011","journal-title":"IEEE Trans. Ind. Electron."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Afsar, Y., Sarik, J., Gorlatova, M., and Zussman, G. (2012, January 3\u20138). Evaluating Photovoltaic Performance Indoors. Proceedings of the 38th IEEE Photovoltaic Specialists Conference (PVSC), Austin, TX, USA.","DOI":"10.1109\/PVSC.2012.6317977"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"1367","DOI":"10.1109\/TIM.2010.2101311","article-title":"Self-Autonomous WSN with wind energy harvesting for remote sensing of wind-driven wildfire spread","volume":"60","author":"Tan","year":"2011","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_45","first-page":"1838","article-title":"Self-powered wireless sensor for air temperature and velocity measurementes with energy harvesting capability","volume":"60","author":"Sardini","year":"2011","journal-title":"IEEE Trans. Ind. Electron."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1405","DOI":"10.1177\/1045389X13486707","article-title":"Large-Scale vibration energy harvesting","volume":"24","author":"Zuo","year":"2013","journal-title":"J. Intell. Mater. Syst. Struct."},{"key":"ref_47","unstructured":"V\u00e1zquez-Rodriguez, M., Jim\u00e9nez, F., and de Frutos, J. (2011). Mathematical Models and Methods in Modern Science, World Scientific and Engineering Academy and Society (WSEAS)."},{"key":"ref_48","unstructured":"(,  2011). Vettri y G. Kausthubh. Green Energy-EZOWATT. Proceedings of the 2011 2nd International Conference on Environmental Science and Technology IPCBEE, Singapore."},{"key":"ref_49","unstructured":"OSGI Alliance OSGI Alliance Web site. [En l\u00ednea]. Available online: http:\/\/www.osgi.org\/Main\/HomePage."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"451","DOI":"10.1007\/s10694-011-0217-x","article-title":"Fire evacuation in underground transportation systems: A review of accidents and empirical research","volume":"49","author":"Fridolf","year":"2013","journal-title":"Fire Technol."},{"key":"ref_51","unstructured":"Martens, M. (2008). Human Factors Aspects in Tunnels: Tunnel User Behaviour and Tunnel Operators, EU FP5 Contract G1RD-CT-2002-766."},{"key":"ref_52","unstructured":"AENOR, EN ISO 7010:2012. 2010."},{"key":"ref_53","unstructured":"Laborda, C.H., Laborda, V.H., Pardo, J.I.A., Lozano, J.P., Bascuas, T.B., Gimeno, \u00c1.A., Mar\u00edn, R.B., Nebra, R.J.C., and Marco, \u00c1.M. (2012). Se\u00f1al con retroiluminaci\u00f3n inteligente y aut\u00f3noma. (U201230980), Espa\u00f1a Patente."},{"key":"ref_54","unstructured":"Qiu, P., Zhao, Y., Heo, U., Zhang, D., and Choi, J. (2010, January 15\u201318). Gateway Architecture for Zigbee Sensor Network for Remote Control over IP Network. Proceedings of the 8th Asia-Pacific Symposium onInformation and Telecommunication Technologies (APSITT), Kuching, Malysia."},{"key":"ref_55","unstructured":"Aragon, D.d.A. Fomento adjudica por 97,2 millones el tramo Alto de Monrep\u00f3s-Caldearenas\u00bb. [En l\u00ednea]. Available online: http:\/\/www.diariodelaltoaragon.es."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/15\/6\/14370\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T20:48:04Z","timestamp":1760215684000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/15\/6\/14370"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,6,18]]},"references-count":55,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2015,6]]}},"alternative-id":["s150614370"],"URL":"https:\/\/doi.org\/10.3390\/s150614370","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2015,6,18]]}}}