{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T19:23:38Z","timestamp":1777058618136,"version":"3.51.4"},"reference-count":52,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2017,8,2]],"date-time":"2017-08-02T00:00:00Z","timestamp":1501632000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Universit\u00e0 Politecnica delle Marche - DII","award":["RSA2016 Progetto PIMRA"],"award-info":[{"award-number":["RSA2016 Progetto PIMRA"]}]},{"name":"COST Action IC1303","award":["STSM 2016"],"award-info":[{"award-number":["STSM 2016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Contactless detection is one of the new frontiers of technological innovation in the field of healthcare, enabling unobtrusive measurements of biomedical parameters. Compared to conventional methods for Heart Rate (HR) detection that employ expensive and\/or uncomfortable devices, such as the Electrocardiograph (ECG) or pulse oximeter, contactless HR detection offers fast and continuous monitoring of heart activities and provides support for clinical analysis without the need for the user to wear a device. This paper presents a validation study for a contactless HR estimation method exploiting RGB (Red, Green, Blue) data from a Microsoft Kinect v2 device. This method, based on Eulerian Video Magnification (EVM), Photoplethysmography (PPG) and Videoplethysmography (VPG), can achieve performance comparable to classical approaches exploiting wearable systems, under specific test conditions. The output given by a Holter, which represents the gold-standard device used in the test for ECG extraction, is considered as the ground-truth, while a comparison with a commercial smartwatch is also included. The validation process is conducted with two modalities that differ for the availability of a priori knowledge about the subjects\u2019 normal HR. The two test modalities provide different results. In particular, the HR estimation differs from the ground-truth by 2% when the knowledge about the subject\u2019s lifestyle and his\/her HR is considered and by 3.4% if no information about the person is taken into account.<\/jats:p>","DOI":"10.3390\/s17081776","type":"journal-article","created":{"date-parts":[[2017,8,2]],"date-time":"2017-08-02T10:05:25Z","timestamp":1501668325000},"page":"1776","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":48,"title":["Heart Rate Detection Using Microsoft Kinect: Validation and Comparison to Wearable Devices"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6852-8483","authenticated-orcid":false,"given":"Ennio","family":"Gambi","sequence":"first","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angela","family":"Agostinelli","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6142-0987","authenticated-orcid":false,"given":"Alberto","family":"Belli","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9474-7046","authenticated-orcid":false,"given":"Laura","family":"Burattini","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Enea","family":"Cippitelli","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sandro","family":"Fioretti","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1436-8864","authenticated-orcid":false,"given":"Paola","family":"Pierleoni","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4870-0914","authenticated-orcid":false,"given":"Manola","family":"Ricciuti","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9152-7216","authenticated-orcid":false,"given":"Agnese","family":"Sbrollini","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7323-4030","authenticated-orcid":false,"given":"Susanna","family":"Spinsante","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 Politecnica delle Marche via Brecce Bianche 12, Ancona 60131, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,8,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1097\/01823246-201122020-00002","article-title":"Blood pressure measurement guidelines for physical therapists","volume":"22","author":"Frese","year":"2011","journal-title":"Cardiopulm. Phys. Ther. J."},{"key":"ref_2","unstructured":"Ward, S., and Hisley, S. (2015). Maternal-Child Nursing Care Optimizing Outcomes for Mothers, Children, & Families, FA Davis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"396","DOI":"10.1136\/hrt.52.4.396","article-title":"New method for assessing cardiac parasympathetic activity using 24 h electrocardiograms","volume":"52","author":"Ewing","year":"1984","journal-title":"Br. Heart J."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"687","DOI":"10.1016\/0735-1097(91)90791-7","article-title":"Risk stratification for arrhythmic events in postinfarction patients based on heart rate variability, ambulatory electrocardiographic variables and the signal-averaged electrocardiogram","volume":"18","author":"Farrell","year":"1991","journal-title":"J. Am. Coll. Cardiol."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Cho, M.C., Kim, J.Y., and Cho, S. (2009, January 24\u201327). A bio-impedance measurement system for portable monitoring of heart rate and pulse wave velocity using small body area. Proceedings of the 2009 IEEE International Symposium on Circuits and Systems, Taipei, Taiwan.","DOI":"10.1109\/ISCAS.2009.5118460"},{"key":"ref_6","unstructured":"Kwon, S., Kim, H., and Park, K.S. (September, January 28). Validation of heart rate extraction using video imaging on a built-in camera system of a smartphone. Proceedings of the 2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, San Diego, CA, USA."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1153","DOI":"10.1109\/JBHI.2013.2291900","article-title":"A Machine Learning Approach to Improve Contactless Heart Rate Monitoring Using a Webcam","volume":"18","author":"Monkaresi","year":"2014","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"23004","DOI":"10.3390\/s150923004","article-title":"New Fast Fall Detection Method Based on Spatio-Temporal Context Tracking of Head by Using Depth Images","volume":"15","author":"Yang","year":"2015","journal-title":"Sensors"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1369","DOI":"10.1007\/s00371-015-1164-1","article-title":"Real-time stress assessment using thermal imaging","volume":"32","author":"Hong","year":"2016","journal-title":"Vis. Comput."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1016\/j.dsp.2015.05.011","article-title":"Bayesian classification and analysis of gait disorders using image and depth sensors of Microsoft Kinect","volume":"47","year":"2015","journal-title":"Digit. Signal Process."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Proch\u00e1zka, A., Sch\u00e4tz, M., Vy\u0161ata, O., and Vali\u0161, M. (2016). Microsoft Kinect Visual and Depth Sensors for Breathing and Heart Rate Analysis. Sensors, 16.","DOI":"10.3390\/s16070996"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Al-Naji, A., Gibson, K., Lee, S.H., and Chahl, J. (2017). Real Time Apnoea Monitoring of Children Using the Microsoft Kinect Sensor: A Pilot Study. Sensors, 17.","DOI":"10.3390\/s17020286"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"21434","DOI":"10.1364\/OE.16.021434","article-title":"Remote plethysmographic imaging using ambient light","volume":"16","author":"Verkruysse","year":"2008","journal-title":"Opt. Express"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1109\/TBME.2010.2086456","article-title":"Advancements in Noncontact, Multiparameter Physiological Measurements Using a Webcam","volume":"58","author":"Poh","year":"2011","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1692","DOI":"10.1109\/TMTT.2017.2650911","article-title":"A Review on Recent Progress of Portable Short-Range Noncontact Microwave Radar Systems","volume":"65","author":"Li","year":"2017","journal-title":"IEEE Trans. Microw. Theory Tech."},{"key":"ref_16","first-page":"1","article-title":"Comparison Study of Noncontact Vital Signs Detection Using a Doppler Stepped-Frequency Continuous-Wave Radar and Camera-Based Imaging Photoplethysmography","volume":"99","author":"Ren","year":"2017","journal-title":"IEEE Trans. Microw. Theory Tech."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1145\/2185520.2185561","article-title":"Eulerian Video Magnification for Revealing Subtle Changes in the World","volume":"31","author":"Wu","year":"2012","journal-title":"ACM Trans. Graph."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Fletcher, R.R., Chamberlain, D., Paggi, N., and Deng, X. (2015, January 25\u201329). Implementation of smart phone video plethysmography and dependence on lighting parameters. Proceedings of the 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), Milan, Italy.","DOI":"10.1109\/EMBC.2015.7319208"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"13070","DOI":"10.3390\/rs71013070","article-title":"Assessment and Calibration of a RGB-D Camera (Kinect v2 Sensor) Towards a Potential Use for Close-Range 3D Modeling","volume":"7","author":"Lachat","year":"2015","journal-title":"Remote Sens."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Dal Mutto, C., Zanuttigh, P., and Cortelazzo, G.M. (2012). Time-of-Flight Cameras and Microsoft Kinect\u2122, Springer Publishing Company, Incorporated.","DOI":"10.1007\/978-1-4614-3807-6"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Zhang, Z. (2012). Microsoft Kinect Sensor and Its Effect, IEEE. 12694803.","DOI":"10.1109\/MMUL.2012.24"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1417","DOI":"10.3390\/s150101417","article-title":"Kinect as a Tool for Gait Analysis: Validation of a Real-Time Joint Extraction Algorithm Working in Side View","volume":"15","author":"Cippitelli","year":"2015","journal-title":"Sensors"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"24297","DOI":"10.3390\/s150924297","article-title":"Leveraging Two Kinect Sensors for Accurate Full-Body Motion Capture","volume":"15","author":"Gao","year":"2015","journal-title":"Sensors"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"4351435","DOI":"10.1155\/2016\/4351435","article-title":"A Human Activity Recognition System Using Skeleton Data from RGBD Sensors","volume":"2016","author":"Cippitelli","year":"2016","journal-title":"Comput. Intell. Neurosci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1023\/B:VISI.0000013087.49260.fb","article-title":"Robust Real-Time Face Detection","volume":"57","author":"Viola","year":"2004","journal-title":"Int. J. Comput. Vis."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"304","DOI":"10.1002\/jor.1100070219","article-title":"Frequency spectrum analysis of wrist motion for activities of daily living","volume":"7","author":"Mann","year":"1989","journal-title":"J. Orthop. Res."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Natarajan, V., and Vyas, A. (2016, January 12\u201314). Power efficient compressive sensing for continuous monitoring of ECG and PPG in a wearable system. Proceedings of the 2016 IEEE 3rd World Forum on Internet of Things (WF-IoT), Reston, VA, USA.","DOI":"10.1109\/WF-IoT.2016.7845493"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Pan, H., Temel, D., and AlRegib, G. (2016, January 25\u201327). HeartBEAT: Heart beat estimation through adaptive tracking. Proceedings of the 2016 IEEE-EMBS International Conference on Biomedical and Health Informatics (BHI), Las Vegas, NV, USA.","DOI":"10.1109\/BHI.2016.7455966"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Mestha, L.K., Kyal, S., Xu, B., Lewis, L.E., and Kumar, V. (2014, January 26\u201330). Towards continuous monitoring of pulse rate in neonatal intensive care unit with a webcam. Proceedings of the 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Chicago, IL, USA.","DOI":"10.1109\/EMBC.2014.6944455"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Secerbegovic, A., Bergsland, J., Halvorsen, P.S., Suljanovic, N., Mujcic, A., and Balasingham, I. (2016, January 13\u201316). Blood pressure estimation using video plethysmography. Proceedings of the 2016 IEEE 13th International Symposium on Biomedical Imaging (ISBI), Prague, Czech Republic.","DOI":"10.1109\/ISBI.2016.7493307"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"More, S.V., and Chaudhari, P.C. (2016, January 23\u201325). Development of non-invasive diagnostic tool for diseases using Photo Plethysmography. Proceedings of the 2016 International Conference on Wireless Communications, Signal Processing and Networking (WiSPNET), Chennai, India.","DOI":"10.1109\/WiSPNET.2016.7566387"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"R1-39","DOI":"10.1088\/0967-3334\/28\/3\/R01","article-title":"Photoplethysmography and its application in clinical physiological measurement","volume":"28","author":"Allen","year":"2007","journal-title":"Physiol. Meas."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Joseph, G., Joseph, A., Titus, G., Thomas, R.M., and Jose, D. (2014, January 24\u201326). Photoplethysmogram (PPG) signal analysis and wavelet de-noising. Proceedings of the 2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA\/iCMMD), Kottayam, India.","DOI":"10.1109\/AICERA.2014.6908199"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"282","DOI":"10.3390\/electronics3020282","article-title":"Wearable photoplethysmographic sensors\u2014Past and present","volume":"3","author":"Tamura","year":"2014","journal-title":"Electronics"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1016\/j.bspc.2014.03.004","article-title":"Non-contact heart rate and heart rate variability measurements: A review","volume":"13","author":"Kranjec","year":"2014","journal-title":"Biomed. Signal Process. Control"},{"key":"ref_36","unstructured":"Zhang, Y.T. (2013, January 7\u20139). Comparison of Heart Rate Variability from PPG with That from ECG. Proceedings of the International Conference on Health Informatics: ICHI 2013, Vilamoura, Portugal."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1006\/jcss.1997.1504","article-title":"A Decision-Theoretic Generalization of On-Line Learning and an Application to Boosting","volume":"55","author":"Freund","year":"1997","journal-title":"J. Comput. Syst. Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1016\/0165-1684(94)90029-9","article-title":"Independent component analysis, A new concept?","volume":"36","author":"Comon","year":"1994","journal-title":"Signal Process."},{"key":"ref_39","unstructured":"Rahman, H., Uddin Ahmed, M., Begum, S., and Funk, P. (2016, January 2\u20133). Real Time Heart Rate Monitoring From Facial RGB Color Video Using Webcam. Proceedings of the 29th Annual Workshop of the Swedish Artificial Intelligence Society (SAIS), Malm\u00f6, Sweden."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1002\/aic.690370209","article-title":"Nonlinear principal component analysis using autoassociative neural networks","volume":"37","author":"Kramer","year":"1991","journal-title":"AIChE J."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Bernacchia, N., Scalise, L., Casacanditella, L., Ercoli, I., Marchionni, P., and Tomasini, E.P. (2014, January 11\u201312). Non contact measurement of heart and respiration rates based on Kinect. Proceedings of the 2014 IEEE International Symposium on Medical Measurements and Applications (MeMeA), Lisboa, Portugal.","DOI":"10.1109\/MeMeA.2014.6860065"},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Iozzia, L., Cerina, L., and Mainardi, L.T. (2016, January 16\u201320). Assessment of beat-to-beat heart rate detection method using a camera as contactless sensor. Proceedings of the 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), Orlando, FL, USA.","DOI":"10.1109\/EMBC.2016.7590754"},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Yu, Y.P., Kwan, B.H., Lim, C.L., Wong, S.L., and Raveendran, P. (2013, January 12\u201315). Video-based heart rate measurement using short-time Fourier transform. Proceedings of the 2013 International Symposium on Intelligent Signal Processing and Communication Systems, Naha-shi, Japan.","DOI":"10.1109\/ISPACS.2013.6704640"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"4711","DOI":"10.1109\/ACCESS.2017.2678521","article-title":"Heart Rate Variability Extraction From Videos Signals: ICA vs. EVM Comparison","volume":"5","author":"Alghoul","year":"2017","journal-title":"IEEE Access"},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Smilkstein, T., Buenrostro, M., Kenyon, A., Lienemann, M., and Larson, G. (2014, January 8\u201310). Heart rate monitoring using Kinect and color amplification. Proceedings of the 2014 IEEE Healthcare Innovation Conference (HIC), Seattle, WA, USA.","DOI":"10.1109\/HIC.2014.7038874"},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Tulyakov, S., Alameda-Pineda, X., Ricci, E., Yin, L., Cohn, J.F., and Sebe, N. (2016, January 27\u201330). Self-Adaptive Matrix Completion for Heart Rate Estimation From Face Videos Under Realistic Conditions. Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition (CVPR), Seattle, WA, USA.","DOI":"10.1109\/CVPR.2016.263"},{"key":"ref_47","first-page":"674","article-title":"An Iterative Image Registration Technique with an Application to Stereo Vision","volume":"Volume 2","author":"Lucas","year":"1981","journal-title":"Proceedings of the 7th International Joint Conference on Artificial Intelligence (IJCAI\u201981)"},{"key":"ref_48","unstructured":"Tomasi, C., and Kanade, T. (1991). Detection and Tracking of Point Features, Carnegie Mellon University. Technical Report CMU-CS-91-132."},{"key":"ref_49","unstructured":"Shi, J., and Tomasi, C. (1994, January 21\u201323). Good features to track. Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, Seattle, WA, USA."},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"(1967). Recommendations for Standardization of Instruments in Electrocardiography and Vectorcardiography. IEEE Trans. Biomed. Eng., BME-14, 60\u201368.","DOI":"10.1109\/TBME.1967.4502467"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"230","DOI":"10.1109\/TBME.1985.325532","article-title":"A Real-Time QRS Detection Algorithm","volume":"BME-32","author":"Pan","year":"1985","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1016\/S0140-6736(86)90837-8","article-title":"Statistical methods for assessing agreement between two methods of clinical measurement","volume":"327","author":"Bland","year":"1986","journal-title":"Lancet"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/8\/1776\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:44:57Z","timestamp":1760208297000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/8\/1776"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,8,2]]},"references-count":52,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2017,8]]}},"alternative-id":["s17081776"],"URL":"https:\/\/doi.org\/10.3390\/s17081776","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,8,2]]}}}