{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,12]],"date-time":"2025-12-12T13:36:00Z","timestamp":1765546560224},"reference-count":50,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2020,3,20]],"date-time":"2020-03-20T00:00:00Z","timestamp":1584662400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2020,3,20]],"date-time":"2020-03-20T00:00:00Z","timestamp":1584662400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["J Wireless Com Network"],"published-print":{"date-parts":[[2020,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Minimizing total harmonic distortion (THD) with less system complexity and computation time is a stringent constraint for many power systems. The multilevel inverter can have low THD when switching angles are selected at the fundamental frequency. For low-order harmonic minimization, selective harmonic elimination (SHE) is the most adopted and proficient technique but it involves the non-linear transcendental equations which are very difficult to solve analytically and numerically. This paper proposes a genetic algorithm (GA)-based optimization technique to minimize the THD of cascaded H-bridge multilevel inverter. The GA is the finest approach for solving such complex equations by obtaining optimized switching angles. The switching angles are calculated by the genetic algorithm by solving the nonlinear transcendental equations. This paper has modeled and simulated a five-level inverter in MATLAB Simulink. The THD comparison is carried out between step modulation method and optimization method. The results reveal that THD has been reduced from 17.88 to 16.74% while third and fifth harmonics have been reduced from 3.24%, 3.7% to 0.84% and 3.3%, respectively. The optimization method along with LC filter significantly improves the power quality providing a complete sinusoidal signal for varying load.<\/jats:p>","DOI":"10.1186\/s13638-020-01686-5","type":"journal-article","created":{"date-parts":[[2020,3,20]],"date-time":"2020-03-20T12:02:59Z","timestamp":1584705779000},"update-policy":"http:\/\/dx.doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Minimization of total harmonic distortions of cascaded H-bridge multilevel inverter by utilizing bio inspired AI algorithm"],"prefix":"10.1186","volume":"2020","author":[{"given":"Muhammad","family":"Salman","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Inzamam Ul","family":"Haq","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tanvir","family":"Ahmad","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haider","family":"Ali","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Affaq","family":"Qamar","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdul","family":"Basit","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Murad","family":"Khan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Javed","family":"Iqbal","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2020,3,20]]},"reference":[{"key":"1686_CR1","doi-asserted-by":"publisher","DOI":"10.1109\/IECON.1997.671773","volume-title":"Cascade multilevel inverters for utility applications","author":"F Peng","year":"1997","unstructured":"F. Peng, J. McKeever, D. Adams, Cascade multilevel inverters for utility applications (Oak Ridge National Lab, TN (United States), 1997)"},{"issue":"11","key":"1686_CR2","doi-asserted-by":"publisher","first-page":"2761","DOI":"10.1016\/j.enconman.2009.06.032","volume":"50","author":"E Babaei","year":"2009","unstructured":"E. Babaei, S.H. Hosseini, New cascaded multilevel inverter topology with minimum number of switches. Energy Conversion and Management50(11), 2761\u20132767 (2009)","journal-title":"Energy Conversion and Management"},{"issue":"2","key":"1686_CR3","doi-asserted-by":"publisher","first-page":"1114","DOI":"10.1016\/j.enconman.2010.09.006","volume":"52","author":"I Colak","year":"2011","unstructured":"I. Colak, E. Kabalci, R. Bayindir, Review of multilevel voltage source inverter topologies and control schemes. Energy conversion and management52(2), 1114\u20131128 (2011)","journal-title":"Energy conversion and management"},{"issue":"4","key":"1686_CR4","doi-asserted-by":"publisher","first-page":"724","DOI":"10.1109\/TIE.2002.801052","volume":"49","author":"J Rodriguez","year":"2002","unstructured":"J. Rodriguez, J.-S. Lai, F.Z. Peng, Multilevel inverters: a survey of topologies, controls, and applications. IEEE Transactions on industrial electronics49(4), 724\u2013738 (2002)","journal-title":"IEEE Transactions on industrial electronics"},{"key":"1686_CR5","doi-asserted-by":"crossref","unstructured":"G. Singh and V. K. Garg, THD analysis of cascaded H-bridge multi-level inverter, in 2017 4th International Conference on Signal Processing, Computing and Control (ISPCC), 2017: IEEE, pp. 229-234.","DOI":"10.1109\/ISPCC.2017.8269680"},{"key":"1686_CR6","unstructured":"J.-S. Lai and F. Z. Peng, Multilevel converters-a new breed of power converters, in IAS'95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting, 1995, vol. 3: IEEE, pp. 2348-2356."},{"key":"1686_CR7","unstructured":"J. Kumar, B. Das, and P. Agarwal, Selective harmonic elimination technique for a multilevel inverter, space, vol. 1, p. 3, 2008."},{"key":"1686_CR8","unstructured":"L. M. Tolbert, J. Chiasson, K. McKenzie, and Z. Du, Elimination of harmonics in a multilevel converter with nonequal DC sources, in Eighteenth Annual IEEE Applied Power Electronics Conference and Exposition, 2003. APEC'03., 2003, vol. 1: IEEE, pp. 589-595."},{"issue":"1","key":"1686_CR9","doi-asserted-by":"publisher","first-page":"122","DOI":"10.1109\/TSMC.1986.289288","volume":"16","author":"JJ Grefenstette","year":"1986","unstructured":"J.J. Grefenstette, Optimization of control parameters for genetic algorithms. IEEE Transactions on systems, man, and cybernetics16(1), 122\u2013128 (1986)","journal-title":"IEEE Transactions on systems, man, and cybernetics"},{"issue":"12","key":"1686_CR10","first-page":"69","volume":"6","author":"N Jalakanuru","year":"2017","unstructured":"N. Jalakanuru, M. Kiber, Switching angle calculation By EP HEP HH And FF Methods For Modified 11-Level Cascade H-Bridge Multilevel Inverter. International Journal of Engineering Science Invention (IJESI)6(12), 69\u201375 (2017)","journal-title":"International Journal of Engineering Science Invention (IJESI)"},{"key":"1686_CR11","unstructured":"B. Ozpineci, L. M. Tolbert, and J. N. Chiasson, Harmonic optimization of multilevel converters using genetic algorithms, in Power Electronics Specialists Conference, 2004. PESC 04. 2004 IEEE 35th Annual, 2004, vol. 5: IEEE, pp. 3911-3916."},{"issue":"2","key":"1686_CR12","doi-asserted-by":"publisher","first-page":"29","DOI":"10.18201\/ijisae.97681","volume":"4","author":"E Bektas","year":"2016","unstructured":"E. Bektas, H. Karaca, GA based selective harmonic elimination for five-level inverter using cascaded H-bridge modules. International Journal of Intelligent Systems and Applications in Engineering4(2), 29\u201332 (2016)","journal-title":"International Journal of Intelligent Systems and Applications in Engineering"},{"issue":"4","key":"1686_CR13","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1145\/2492248.2492271","volume":"38","author":"D Rai","year":"2013","unstructured":"D. Rai, K. Tyagi, Bio-inspired optimization techniques: a critical comparative study. ACM SIGSOFT Software Engineering Notes38(4), 1\u20137 (2013)","journal-title":"ACM SIGSOFT Software Engineering Notes"},{"key":"1686_CR14","doi-asserted-by":"crossref","unstructured":"S. Ramkumar, V. Kamaraj, and S. Thamizharasan, GA based optimization and critical evaluation SHE methods for three-level inverter, in 2011 1st International Conference on Electrical Energy Systems, 2011: IEEE, pp. 115-121.","DOI":"10.1109\/ICEES.2011.5725313"},{"key":"1686_CR15","unstructured":"Z. Du, L. M. Tolbert, J. N. Chiasson, and H. Li, Low switching frequency active harmonic elimination in multilevel converters with unequal DC voltages, in Fourtieth IAS Annual Meeting. Conference Record of the 2005 Industry Applications Conference, 2005., 2005, vol. 1: IEEE, pp. 92-98."},{"issue":"15","key":"1686_CR16","first-page":"3088","volume":"14","author":"M Nandhini Gayathri","year":"2008","unstructured":"M. Nandhini Gayathri et al., Active harmonic elimination for multilevel converters. Journal of Applied Sciences14(15), 3088\u20133099 (2008)","journal-title":"Journal of Applied Sciences"},{"key":"1686_CR17","doi-asserted-by":"crossref","unstructured":"T. Tang, J. Han, and X. Tan, Selective harmonic elimination for a cascade multilevel inverter, in 2006 IEEE International Symposium on Industrial Electronics, 2006, vol. 2: IEEE, pp. 977-981.","DOI":"10.1109\/ISIE.2006.295768"},{"issue":"11","key":"1686_CR18","doi-asserted-by":"publisher","first-page":"3678","DOI":"10.1109\/TIE.2010.2041736","volume":"57","author":"H Taghizadeh","year":"2010","unstructured":"H. Taghizadeh, M.T. Hagh, Harmonic elimination of cascade multilevel inverters with nonequal DC sources using particle swarm optimization. IEEE Transactions on Industrial Electronics57(11), 3678\u20133684 (2010)","journal-title":"IEEE Transactions on Industrial Electronics"},{"issue":"4","key":"1686_CR19","doi-asserted-by":"publisher","first-page":"1620","DOI":"10.1109\/TPEL.2008.925179","volume":"23","author":"MS Dahidah","year":"2008","unstructured":"M.S. Dahidah, V.G. Agelidis, Selective harmonic elimination PWM control for cascaded multilevel voltage source converters: a generalized formula. IEEE Transactions on power electronics23(4), 1620\u20131630 (2008)","journal-title":"IEEE Transactions on power electronics"},{"issue":"6","key":"1686_CR20","doi-asserted-by":"publisher","first-page":"1337","DOI":"10.1109\/TPEL.2005.857541","volume":"20","author":"JR Wells","year":"2005","unstructured":"J.R. Wells, B.M. Nee, P.L. Chapman, P.T. Krein, Selective harmonic control: a general problem formulation and selected solutions. IEEE Transactions on Power Electronics20(6), 1337\u20131345 (2005)","journal-title":"IEEE Transactions on Power Electronics"},{"issue":"5","key":"1686_CR21","doi-asserted-by":"publisher","first-page":"4212","DOI":"10.1109\/TIA.2015.2437351","volume":"51","author":"A Edpuganti","year":"2015","unstructured":"A. Edpuganti, A.K. Rathore, A survey of low switching frequency modulation techniques for medium-voltage multilevel converters. IEEE Transactions on Industry Applications51(5), 4212\u20134228 (2015)","journal-title":"IEEE Transactions on Industry Applications"},{"issue":"1","key":"1686_CR22","doi-asserted-by":"publisher","first-page":"160","DOI":"10.1109\/28.821811","volume":"36","author":"L Li","year":"2000","unstructured":"L. Li, D. Czarkowski, Y. Liu, P. Pillay, Multilevel selective harmonic elimination PWM technique in series-connected voltage inverters. IEEE Transactions on Industry Applications36(1), 160\u2013170 (2000)","journal-title":"IEEE Transactions on Industry Applications"},{"key":"1686_CR23","unstructured":"J. Sun and I. Grotstollen, Pulsewidth modulation based on real-time solution of algebraic harmonic elimination equations, in Proceedings of IECON'94-20th Annual Conference of IEEE Industrial Electronics, 1994, vol. 1: IEEE, pp. 79-84."},{"key":"1686_CR24","unstructured":"L. M. Tolbert and F. Z. Peng, Multilevel converters for large electric drives, in APEC'98 Thirteenth Annual Applied Power Electronics Conference and Exposition, 1998, vol. 2: IEEE, pp. 530-536."},{"issue":"1","key":"1686_CR25","doi-asserted-by":"publisher","first-page":"89","DOI":"10.1016\/j.enconman.2007.05.014","volume":"49","author":"K El-Naggar","year":"2008","unstructured":"K. El-Naggar, T.H. Abdelhamid, Selective harmonic elimination of new family of multilevel inverters using genetic algorithms. Energy Conversion and Management49(1), 89\u201395 (2008)","journal-title":"Energy Conversion and Management"},{"key":"1686_CR26","doi-asserted-by":"crossref","unstructured":"M. D. Patil and R. G. Ramteke, LC filter design implementation and comparative study with various PWM techniques for DCMLI, in 2015 International Conference on Energy Systems and Applications, 2015: IEEE, pp. 347-352.","DOI":"10.1109\/ICESA.2015.7503369"},{"issue":"2","key":"1686_CR27","first-page":"191","volume":"3","author":"O Bouhali","year":"2013","unstructured":"O. Bouhali, F. Bouaziz, N. Rizoug, A. Talha, Solving harmonic elimination equations in multi-levelinverters by using neural networks. International journal of information and electronics engineering3(2), 191 (2013)","journal-title":"International journal of information and electronics engineering"},{"key":"1686_CR28","unstructured":"D. Kumar, S. Pattnaik, and V. J. I. Singh, Genetic algorithm based approach for optimization of conducting angles in cascaded multilevel inverter, vol. 2, no. 3, pp. 2389-2395, 2012."},{"key":"1686_CR29","doi-asserted-by":"crossref","unstructured":"K. T. Eddine, R. Abdelhadi, B. Omar, and O. Hassan, A new multilevel inverter with genetic algorithm optimization for hybrid power station application, in 2018 4th International Conference on Optimization and Applications (ICOA), 2018: IEEE, pp. 1-6.","DOI":"10.1109\/ICOA.2018.8370499"},{"key":"1686_CR30","doi-asserted-by":"crossref","unstructured":"M. A. Hosseinzadeh, M. Sarbanzadeh, Y. Salgueiro, M. Rivera, and P. Wheeler, Selective harmonic elimination in cascaded H-bridge multilevel inverter using genetic algorithm approach, in 2019 IEEE International Conference on Industrial Technology, 2019, pp. 1527-1532.","DOI":"10.1109\/ICIT.2019.8755089"},{"key":"1686_CR31","doi-asserted-by":"crossref","unstructured":"F. Al-Turjman, M.H. Nawaz, U.D. Ulusar, Intelligence in the Internet of medical things era: a systematic review of current and future trends. Computer Communications (2019)","DOI":"10.1016\/j.comcom.2019.12.030"},{"key":"1686_CR32","doi-asserted-by":"crossref","unstructured":"F. Campioni, S. Choudhury, F. Al-Turjman, Scheduling RFID networks in the IoT and smart health era. Journal of Ambient Intelligence and Humanized Computing, 1\u201315 (2019)","DOI":"10.1109\/ICCW.2018.8403753"},{"key":"1686_CR33","doi-asserted-by":"publisher","first-page":"115749","DOI":"10.1109\/ACCESS.2019.2931637","volume":"7","author":"F Al-Turjman","year":"2019","unstructured":"F. Al-Turjman, H. Zahmatkesh, L. Mostarda, Quantifying uncertainty in internet of medical things and big-data services using intelligence and deep learning. IEEE Access7, 115749\u2013115759 (2019)","journal-title":"IEEE Access"},{"key":"1686_CR34","doi-asserted-by":"crossref","unstructured":"N. Karnik, D. Singla, and P. Sharma, Comparative analysis of harmonic reduction in multilevel inverter, in 2012 IEEE Fifth Power India Conference, 2012: IEEE, pp. 1-5.","DOI":"10.1109\/PowerI.2012.6479521"},{"key":"1686_CR35","doi-asserted-by":"crossref","unstructured":"Y. Fong and K. E. Cheng, An adaptive modulation scheme for fundamental frequency switched multilevel inverter with unbalanced and varying voltage sources, in 2015 6th International Conference on Power Electronics Systems and Applications (PESA), 2015: IEEE, pp. 1-6.","DOI":"10.1109\/PESA.2015.7398931"},{"key":"1686_CR36","doi-asserted-by":"crossref","unstructured":"K. S. Neralwar, P. Meshram, and V. Borghate, Genetic algorithm (GA) based SHE technique applied to seven-level Nested Neutral Point Clamped (NNPC) Converter, in 2016 IEEE 1st International Conference on Power Electronics, Intelligent Control and Energy Systems (ICPEICES), 2016: IEEE, pp. 1-6.","DOI":"10.1109\/ICPEICES.2016.7853181"},{"issue":"10","key":"1686_CR37","doi-asserted-by":"publisher","first-page":"2743","DOI":"10.1109\/TPEL.2011.2116042","volume":"26","author":"D Ahmadi","year":"2011","unstructured":"D. Ahmadi, K. Zou, C. Li, Y. Huang, J. Wang, A universal selective harmonic elimination method for high-power inverters. IEEE Transactions on power electronics26(10), 2743\u20132752 (2011)","journal-title":"IEEE Transactions on power electronics"},{"key":"1686_CR38","unstructured":"F. Peng and J. Lai, A static var generator using a staircase waveform multilevel voltage-source converter, in Proc. Rec. Power Quality Conf, 1994, pp. 58-66."},{"issue":"2","key":"1686_CR39","first-page":"138","volume":"24","author":"H Karaca","year":"2016","unstructured":"H. Karaca, E. Bektas, Selective harmonic elimination using genetic algorithm for multilevel inverter with reduced number of power switches. Engineering Letters24(2), 138\u2013143 (2016)","journal-title":"Engineering Letters"},{"issue":"4","key":"1686_CR40","doi-asserted-by":"publisher","first-page":"1753","DOI":"10.1016\/j.rser.2010.12.008","volume":"15","author":"R Banos","year":"2011","unstructured":"R. Banos, F. Manzano-Agugliaro, F. Montoya, C. Gil, A. Alcayde, J. G\u00f3mez, Optimization methods applied to renewable and sustainable energy: a review. Renewable and sustainable energy reviews15(4), 1753\u20131766 (2011)","journal-title":"Renewable and sustainable energy reviews"},{"key":"1686_CR41","volume-title":"Numerical methods for solving systems of nonlinear equations","author":"C Remani","year":"2013","unstructured":"C. Remani, Numerical methods for solving systems of nonlinear equations (Lakehead University Thunder Bay, Ontario, Canada, 2013)"},{"key":"1686_CR42","first-page":"121","volume":"3","author":"L Davis","year":"1988","unstructured":"L. Davis, Handbook of genetic algorithms (New York, Van Nostrand Reinhold, 1991). K AD long Machine Learning3, 121 (1988)","journal-title":"K AD long Machine Learning"},{"issue":"2","key":"1686_CR43","doi-asserted-by":"publisher","first-page":"95","DOI":"10.1023\/A:1022602019183","volume":"3","author":"DE Goldberg","year":"1988","unstructured":"D.E. Goldberg, J.H. Holland, Genetic algorithms and machine learning. Machine learning3(2), 95\u201399 (1988)","journal-title":"Machine learning"},{"key":"1686_CR44","doi-asserted-by":"crossref","unstructured":"J. H. Holland, Adaptation in natural and artificial systems: an introductory analysis with applications to biology, control, and artificial intelligence. MIT press, 1992.","DOI":"10.7551\/mitpress\/1090.001.0001"},{"key":"1686_CR45","unstructured":"Z. Michalewicz, Genetic algorithms+ data structures= evolution programs. Springer Science & Business Media, 2013."},{"issue":"5","key":"1686_CR46","doi-asserted-by":"publisher","first-page":"519","DOI":"10.1109\/41.538609","volume":"43","author":"K-F Man","year":"1996","unstructured":"K.-F. Man, K.-S. Tang, S. Kwong, Genetic algorithms: concepts and applications [in engineering design]. IEEE transactions on Industrial Electronics43(5), 519\u2013534 (1996)","journal-title":"IEEE transactions on Industrial Electronics"},{"key":"1686_CR47","unstructured":"J. T. Alander, On optimal population size of genetic algorithms, in CompEuro 1992 Proceedings computer systems and software engineering, 1992: IEEE, pp. 65-70."},{"issue":"1","key":"1686_CR48","doi-asserted-by":"publisher","first-page":"213","DOI":"10.1109\/MAP.2011.5773620","volume":"53","author":"MA Uslu","year":"2011","unstructured":"M.A. Uslu, L. Sevy, A MATLAB-based filter-design program: from lumped elements to microstrip lines. IEEE Antennas and Propagation Magazine53(1), 213\u2013224 (2011)","journal-title":"IEEE Antennas and Propagation Magazine"},{"issue":"6","key":"1686_CR49","doi-asserted-by":"publisher","first-page":"727","DOI":"10.1016\/j.solener.2004.09.008","volume":"78","author":"F-s Kang","year":"2005","unstructured":"F.-s. Kang, S.E. Cho, S.-J. Park, C.-U. Kim, T. Ise, A new control scheme of a cascaded transformer type multilevel PWM inverter for a residential photovoltaic power conditioning system. Solar Energy78(6), 727\u2013738 (2005)","journal-title":"Solar Energy"},{"issue":"2","key":"1686_CR50","doi-asserted-by":"publisher","first-page":"285","DOI":"10.1109\/TIE.2008.918461","volume":"56","author":"Y Liu","year":"2008","unstructured":"Y. Liu, H. Hong, A.Q. Huang, Real-time calculation of switching angles minimizing THD for multilevel inverters with step modulation. IEEE Transactions on Industrial Electronics56(2), 285\u2013293 (2008)","journal-title":"IEEE Transactions on Industrial Electronics"}],"container-title":["EURASIP Journal on Wireless Communications and Networking"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/link.springer.com\/content\/pdf\/10.1186\/s13638-020-01686-5.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"http:\/\/link.springer.com\/article\/10.1186\/s13638-020-01686-5\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"http:\/\/link.springer.com\/content\/pdf\/10.1186\/s13638-020-01686-5.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,3,20]],"date-time":"2021-03-20T00:39:10Z","timestamp":1616200750000},"score":1,"resource":{"primary":{"URL":"https:\/\/jwcn-eurasipjournals.springeropen.com\/articles\/10.1186\/s13638-020-01686-5"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,3,20]]},"references-count":50,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2020,12]]}},"alternative-id":["1686"],"URL":"https:\/\/doi.org\/10.1186\/s13638-020-01686-5","relation":{},"ISSN":["1687-1499"],"issn-type":[{"value":"1687-1499","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,3,20]]},"assertion":[{"value":"24 September 2019","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"6 March 2020","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"20 March 2020","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"The authors declare that they have no competing interests.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"66"}}