{"id":"https://openalex.org/W2131926118","doi":"https://doi.org/10.1109/tie.2011.2112317","title":"Maximizing Air Gap and Efficiency of Magnetic Resonant Coupling for Wireless Power Transfer Using Equivalent Circuit and Neumann Formula","display_name":"Maximizing Air Gap and Efficiency of Magnetic Resonant Coupling for Wireless Power Transfer Using Equivalent Circuit and Neumann Formula","publication_year":2011,"publication_date":"2011-02-03","ids":{"openalex":"https://openalex.org/W2131926118","doi":"https://doi.org/10.1109/tie.2011.2112317","mag":"2131926118"},"language":"en","primary_location":{"id":"doi:10.1109/tie.2011.2112317","is_oa":false,"landing_page_url":"https://doi.org/10.1109/tie.2011.2112317","pdf_url":null,"source":{"id":"https://openalex.org/S58031724","display_name":"IEEE Transactions on Industrial Electronics","issn_l":"0278-0046","issn":["0278-0046","1557-9948"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310319808","host_organization_name":"Institute of Electrical and Electronics Engineers","host_organization_lineage":["https://openalex.org/P4310319808"],"host_organization_lineage_names":["Institute of Electrical and Electronics Engineers"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"IEEE Transactions on Industrial Electronics","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5063826622","display_name":"Takehiro Imura","orcid":"https://orcid.org/0000-0003-4174-2185"},"institutions":[{"id":"https://openalex.org/I74801974","display_name":"The University of Tokyo","ror":"https://ror.org/057zh3y96","country_code":"JP","type":"education","lineage":["https://openalex.org/I74801974"]}],"countries":["JP"],"is_corresponding":false,"raw_author_name":"Takehiro Imura","raw_affiliation_strings":["Department of Advanced Energy, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan","[Department of Advanced Energy, University of Tokyo, Kashiwa, Japan]"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Advanced Energy, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan","institution_ids":["https://openalex.org/I74801974"]},{"raw_affiliation_string":"[Department of Advanced Energy, University of Tokyo, Kashiwa, Japan]","institution_ids":["https://openalex.org/I74801974"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5108536663","display_name":"Yoichi Hori","orcid":null},"institutions":[{"id":"https://openalex.org/I74801974","display_name":"The University of Tokyo","ror":"https://ror.org/057zh3y96","country_code":"JP","type":"education","lineage":["https://openalex.org/I74801974"]}],"countries":["JP"],"is_corresponding":false,"raw_author_name":"Yoichi Hori","raw_affiliation_strings":["Department of Advanced Energy, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan","[Department of Advanced Energy, University of Tokyo, Kashiwa, Japan]"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Advanced Energy, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan","institution_ids":["https://openalex.org/I74801974"]},{"raw_affiliation_string":"[Department of Advanced Energy, University of Tokyo, Kashiwa, Japan]","institution_ids":["https://openalex.org/I74801974"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":2,"corresponding_author_ids":[],"corresponding_institution_ids":[],"apc_list":null,"apc_paid":null,"fwci":31.355,"has_fulltext":false,"cited_by_count":582,"citation_normalized_percentile":{"value":0.99804567,"is_in_top_1_percent":true,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":99,"max":100},"biblio":{"volume":"58","issue":"10","first_page":"4746","last_page":"4752"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11249","display_name":"Wireless Power Transfer Systems","score":1.0,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T11249","display_name":"Wireless Power Transfer Systems","score":1.0,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11392","display_name":"Energy Harvesting in Wireless Networks","score":0.9998999834060669,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10986","display_name":"RFID technology advancements","score":0.9929999709129333,"subfield":{"id":"https://openalex.org/subfields/2214","display_name":"Media Technology"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/wireless-power-transfer","display_name":"Wireless power transfer","score":0.8349310755729675},{"id":"https://openalex.org/keywords/maximum-power-transfer-theorem","display_name":"Maximum power transfer theorem","score":0.6392176151275635},{"id":"https://openalex.org/keywords/air-gap","display_name":"Air gap (plumbing)","score":0.5881408452987671},{"id":"https://openalex.org/keywords/electrical-engineering","display_name":"Electrical engineering","score":0.5561397075653076},{"id":"https://openalex.org/keywords/wireless","display_name":"Wireless","score":0.5537869334220886},{"id":"https://openalex.org/keywords/inductance","display_name":"Inductance","score":0.5515246391296387},{"id":"https://openalex.org/keywords/electronic-circuit","display_name":"Electronic circuit","score":0.5354983806610107},{"id":"https://openalex.org/keywords/electronic-engineering","display_name":"Electronic engineering","score":0.49258118867874146},{"id":"https://openalex.org/keywords/power","display_name":"Power (physics)","score":0.4910924434661865},{"id":"https://openalex.org/keywords/equivalent-circuit","display_name":"Equivalent circuit","score":0.4595796465873718},{"id":"https://openalex.org/keywords/engineering","display_name":"Engineering","score":0.4583960473537445},{"id":"https://openalex.org/keywords/electromagnetic-field","display_name":"Electromagnetic field","score":0.42247718572616577},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.33390018343925476},{"id":"https://openalex.org/keywords/telecommunications","display_name":"Telecommunications","score":0.2578889727592468},{"id":"https://openalex.org/keywords/physics","display_name":"Physics","score":0.2078254222869873},{"id":"https://openalex.org/keywords/voltage","display_name":"Voltage","score":0.2020832896232605},{"id":"https://openalex.org/keywords/materials-science","display_name":"Materials science","score":0.10456192493438721}],"concepts":[{"id":"https://openalex.org/C2779423816","wikidata":"https://www.wikidata.org/wiki/Q6856398","display_name":"Wireless power transfer","level":3,"score":0.8349310755729675},{"id":"https://openalex.org/C67186554","wikidata":"https://www.wikidata.org/wiki/Q17103352","display_name":"Maximum power transfer theorem","level":3,"score":0.6392176151275635},{"id":"https://openalex.org/C50587689","wikidata":"https://www.wikidata.org/wiki/Q4698328","display_name":"Air gap (plumbing)","level":2,"score":0.5881408452987671},{"id":"https://openalex.org/C119599485","wikidata":"https://www.wikidata.org/wiki/Q43035","display_name":"Electrical engineering","level":1,"score":0.5561397075653076},{"id":"https://openalex.org/C555944384","wikidata":"https://www.wikidata.org/wiki/Q249","display_name":"Wireless","level":2,"score":0.5537869334220886},{"id":"https://openalex.org/C29210110","wikidata":"https://www.wikidata.org/wiki/Q177897","display_name":"Inductance","level":3,"score":0.5515246391296387},{"id":"https://openalex.org/C134146338","wikidata":"https://www.wikidata.org/wiki/Q1815901","display_name":"Electronic circuit","level":2,"score":0.5354983806610107},{"id":"https://openalex.org/C24326235","wikidata":"https://www.wikidata.org/wiki/Q126095","display_name":"Electronic engineering","level":1,"score":0.49258118867874146},{"id":"https://openalex.org/C163258240","wikidata":"https://www.wikidata.org/wiki/Q25342","display_name":"Power (physics)","level":2,"score":0.4910924434661865},{"id":"https://openalex.org/C23572009","wikidata":"https://www.wikidata.org/wiki/Q964981","display_name":"Equivalent circuit","level":3,"score":0.4595796465873718},{"id":"https://openalex.org/C127413603","wikidata":"https://www.wikidata.org/wiki/Q11023","display_name":"Engineering","level":0,"score":0.4583960473537445},{"id":"https://openalex.org/C28843909","wikidata":"https://www.wikidata.org/wiki/Q177625","display_name":"Electromagnetic field","level":2,"score":0.42247718572616577},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.33390018343925476},{"id":"https://openalex.org/C76155785","wikidata":"https://www.wikidata.org/wiki/Q418","display_name":"Telecommunications","level":1,"score":0.2578889727592468},{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.2078254222869873},{"id":"https://openalex.org/C165801399","wikidata":"https://www.wikidata.org/wiki/Q25428","display_name":"Voltage","level":2,"score":0.2020832896232605},{"id":"https://openalex.org/C192562407","wikidata":"https://www.wikidata.org/wiki/Q228736","display_name":"Materials science","level":0,"score":0.10456192493438721},{"id":"https://openalex.org/C62520636","wikidata":"https://www.wikidata.org/wiki/Q944","display_name":"Quantum mechanics","level":1,"score":0.0},{"id":"https://openalex.org/C159985019","wikidata":"https://www.wikidata.org/wiki/Q181790","display_name":"Composite material","level":1,"score":0.0}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1109/tie.2011.2112317","is_oa":false,"landing_page_url":"https://doi.org/10.1109/tie.2011.2112317","pdf_url":null,"source":{"id":"https://openalex.org/S58031724","display_name":"IEEE Transactions on Industrial Electronics","issn_l":"0278-0046","issn":["0278-0046","1557-9948"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310319808","host_organization_name":"Institute of Electrical and Electronics Engineers","host_organization_lineage":["https://openalex.org/P4310319808"],"host_organization_lineage_names":["Institute of Electrical and Electronics Engineers"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"IEEE Transactions on Industrial Electronics","raw_type":"journal-article"}],"best_oa_location":null,"sustainable_development_goals":[{"score":0.8799999952316284,"id":"https://metadata.un.org/sdg/7","display_name":"Affordable and clean energy"}],"awards":[],"funders":[],"has_content":{"grobid_xml":false,"pdf":false},"content_urls":null,"referenced_works_count":29,"referenced_works":["https://openalex.org/W1971234442","https://openalex.org/W1985705155","https://openalex.org/W1998024244","https://openalex.org/W2018287241","https://openalex.org/W2035632402","https://openalex.org/W2037726546","https://openalex.org/W2060113616","https://openalex.org/W2066033083","https://openalex.org/W2079865842","https://openalex.org/W2081198853","https://openalex.org/W2087657930","https://openalex.org/W2107367628","https://openalex.org/W2113688027","https://openalex.org/W2113769146","https://openalex.org/W2126015357","https://openalex.org/W2128737020","https://openalex.org/W2135819865","https://openalex.org/W2139125750","https://openalex.org/W2145520800","https://openalex.org/W2148069046","https://openalex.org/W2162117114","https://openalex.org/W2163108953","https://openalex.org/W2200612226","https://openalex.org/W2387715584","https://openalex.org/W2605671811","https://openalex.org/W2945601770","https://openalex.org/W6646742103","https://openalex.org/W6687766236","https://openalex.org/W6736920973"],"related_works":["https://openalex.org/W2905502739","https://openalex.org/W2910860274","https://openalex.org/W2909929675","https://openalex.org/W2554870471","https://openalex.org/W4205317126","https://openalex.org/W2236924022","https://openalex.org/W2763444231","https://openalex.org/W2740114034","https://openalex.org/W2776674530","https://openalex.org/W3162533627"],"abstract_inverted_index":{"The":[0,64,172],"progress":[1],"in":[2,9,70,74,110],"the":[3,10,133,142,153,160,180],"field":[4,184],"of":[5,174,182],"wireless":[6,38,59],"power":[7,20,39,60,82],"transfer":[8,40,61],"last":[11],"few":[12],"years":[13],"is":[14,62,93,124],"remarkable.":[15],"With":[16],"recent":[17],"research,":[18],"transferring":[19],"across":[21],"large":[22,31,50,85],"air":[23,86,147,170],"gaps":[24,87],"has":[25,100],"been":[26,35,101],"achieved.":[27],"Both":[28],"small":[29,42],"and":[30,46,48,72,77,99,105,118,152,156,186],"electric":[32,78],"equipment":[33,43,51],"have":[34,114],"proposed,":[36],"e.g.,":[37],"for":[41,49,108,129,159,167],"(mobile":[44],"phones":[45],"laptops)":[47],"(electric":[52],"vehicles).":[53],"Furthermore,":[54],"replacing":[55],"every":[56],"cord":[57],"with":[58,88,179],"proposed.":[63],"coupled":[65,134],"mode":[66,135],"theory":[67],"was":[68],"proposed":[69,157],"2006":[71],"proven":[73],"2007.":[75],"Magnetic":[76],"resonant":[79],"couplings":[80],"allow":[81],"to":[83,96,103,163],"traverse":[84],"high":[89],"efficiency.":[90],"This":[91],"technology":[92],"closely":[94],"related":[95],"electromagnetic":[97,183],"induction":[98],"applied":[102],"antennas":[104],"resonators":[106],"used":[107],"filters":[109],"communication":[111],"technology.":[112],"We":[113],"studied":[115],"these":[116,175],"phenomena":[117],"technologies":[119],"using":[120,149],"equivalent":[121,150],"circuits,":[122],"which":[123],"a":[125,168],"more":[126],"familiar":[127],"format":[128],"electrical":[130],"engineers":[131],"than":[132],"theory.":[136],"In":[137],"this":[138],"paper,":[139],"we":[140],"analyzed":[141],"relationship":[143],"between":[144],"maximum":[145,165],"efficiency":[146,166],"gap":[148],"circuits":[151],"Neumann":[154],"formula":[155],"equations":[158,176],"conditions":[161],"required":[162],"achieve":[164],"given":[169],"gap.":[171],"results":[173,181],"match":[177],"well":[178],"analysis":[185],"experiments.":[187]},"counts_by_year":[{"year":2026,"cited_by_count":5},{"year":2025,"cited_by_count":17},{"year":2024,"cited_by_count":9},{"year":2023,"cited_by_count":32},{"year":2022,"cited_by_count":32},{"year":2021,"cited_by_count":34},{"year":2020,"cited_by_count":36},{"year":2019,"cited_by_count":44},{"year":2018,"cited_by_count":58},{"year":2017,"cited_by_count":67},{"year":2016,"cited_by_count":68},{"year":2015,"cited_by_count":64},{"year":2014,"cited_by_count":44},{"year":2013,"cited_by_count":41},{"year":2012,"cited_by_count":28}],"updated_date":"2026-06-11T09:08:48.828518","created_date":"2025-10-10T00:00:00"}