{"id":"https://openalex.org/W1982378832","doi":"https://doi.org/10.3390/rs70404527","title":"A Comparison of Two Approaches for Estimating the Wheat Nitrogen Nutrition Index Using Remote Sensing","display_name":"A Comparison of Two Approaches for Estimating the Wheat Nitrogen Nutrition Index Using Remote Sensing","publication_year":2015,"publication_date":"2015-04-15","ids":{"openalex":"https://openalex.org/W1982378832","doi":"https://doi.org/10.3390/rs70404527","mag":"1982378832"},"language":"en","primary_location":{"id":"doi:10.3390/rs70404527","is_oa":true,"landing_page_url":"https://doi.org/10.3390/rs70404527","pdf_url":"https://www.mdpi.com/2072-4292/7/4/4527/pdf?version=1429088447","source":{"id":"https://openalex.org/S43295729","display_name":"Remote Sensing","issn_l":"2072-4292","issn":["2072-4292"],"is_oa":true,"is_in_doaj":true,"is_core":true,"host_organization":"https://openalex.org/P4310310987","host_organization_name":"Multidisciplinary Digital Publishing Institute","host_organization_lineage":["https://openalex.org/P4310310987"],"host_organization_lineage_names":["Multidisciplinary Digital Publishing Institute"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Remote Sensing","raw_type":"journal-article"},"type":"article","indexed_in":["crossref","doaj"],"open_access":{"is_oa":true,"oa_status":"gold","oa_url":"https://www.mdpi.com/2072-4292/7/4/4527/pdf?version=1429088447","any_repository_has_fulltext":true},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5100335047","display_name":"Pengfei Chen","orcid":"https://orcid.org/0000-0001-5530-7139"},"institutions":[{"id":"https://openalex.org/I19820366","display_name":"Chinese Academy of Sciences","ror":"https://ror.org/034t30j35","country_code":"CN","type":"government","lineage":["https://openalex.org/I19820366"]},{"id":"https://openalex.org/I4210141657","display_name":"Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application","ror":"https://ror.org/045yewh40","country_code":"CN","type":"facility","lineage":["https://openalex.org/I152031979","https://openalex.org/I4210141657"]},{"id":"https://openalex.org/I4210160793","display_name":"Institute of Geographic Sciences and Natural Resources Research","ror":"https://ror.org/04t1cdb72","country_code":"CN","type":"facility","lineage":["https://openalex.org/I19820366","https://openalex.org/I4210160793"]}],"countries":["CN"],"is_corresponding":true,"raw_author_name":"Pengfei Chen","raw_affiliation_strings":["Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China\u00a0","State Key Laboratory of Resources and Environment Information System, Institute of Geographical Science and Natural Resources Research, Chinese Academy of Sciences, Datun Road A11,  Chaoyang District, Beijing 100101, China","State Key Laboratory of Resources and Environment Information System, Institute of Geographical Science and Natural Resources Research, Chinese Academy of Sciences, Datun Road A11, Chaoyang District, Beijing 100101, China"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China\u00a0","institution_ids":["https://openalex.org/I4210141657"]},{"raw_affiliation_string":"State Key Laboratory of Resources and Environment Information System, Institute of Geographical Science and Natural Resources Research, Chinese Academy of Sciences, Datun Road A11,  Chaoyang District, Beijing 100101, China","institution_ids":["https://openalex.org/I4210160793"]},{"raw_affiliation_string":"State Key Laboratory of Resources and Environment Information System, Institute of Geographical Science and Natural Resources Research, Chinese Academy of Sciences, Datun Road A11, Chaoyang District, Beijing 100101, China","institution_ids":["https://openalex.org/I19820366","https://openalex.org/I4210160793"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":3,"corresponding_author_ids":["https://openalex.org/A5100335047"],"corresponding_institution_ids":["https://openalex.org/I19820366","https://openalex.org/I4210141657","https://openalex.org/I4210160793"],"apc_list":{"value":2500,"currency":"CHF","value_usd":2784},"apc_paid":{"value":2500,"currency":"CHF","value_usd":2784},"fwci":3.1405,"has_fulltext":true,"cited_by_count":64,"citation_normalized_percentile":{"value":0.9044831,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":90,"max":99},"biblio":{"volume":"7","issue":"4","first_page":"4527","last_page":"4548"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10111","display_name":"Remote Sensing in Agriculture","score":0.9998000264167786,"subfield":{"id":"https://openalex.org/subfields/2303","display_name":"Ecology"},"field":{"id":"https://openalex.org/fields/23","display_name":"Environmental Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T10111","display_name":"Remote Sensing in Agriculture","score":0.9998000264167786,"subfield":{"id":"https://openalex.org/subfields/2303","display_name":"Ecology"},"field":{"id":"https://openalex.org/fields/23","display_name":"Environmental Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11164","display_name":"Remote Sensing and LiDAR Applications","score":0.9962999820709229,"subfield":{"id":"https://openalex.org/subfields/2305","display_name":"Environmental Engineering"},"field":{"id":"https://openalex.org/fields/23","display_name":"Environmental Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10266","display_name":"Plant Water Relations and Carbon Dynamics","score":0.9908999800682068,"subfield":{"id":"https://openalex.org/subfields/2306","display_name":"Global and Planetary Change"},"field":{"id":"https://openalex.org/fields/23","display_name":"Environmental Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/mean-squared-error","display_name":"Mean squared error","score":0.5960111618041992},{"id":"https://openalex.org/keywords/calibration","display_name":"Calibration","score":0.5773704051971436},{"id":"https://openalex.org/keywords/phenology","display_name":"Phenology","score":0.490792840719223},{"id":"https://openalex.org/keywords/statistics","display_name":"Statistics","score":0.451842337846756},{"id":"https://openalex.org/keywords/nitrogen","display_name":"Nitrogen","score":0.41676488518714905},{"id":"https://openalex.org/keywords/environmental-science","display_name":"Environmental science","score":0.407698392868042},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.39386919140815735},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.37833505868911743},{"id":"https://openalex.org/keywords/remote-sensing","display_name":"Remote sensing","score":0.3593628406524658},{"id":"https://openalex.org/keywords/agronomy","display_name":"Agronomy","score":0.14100536704063416},{"id":"https://openalex.org/keywords/chemistry","display_name":"Chemistry","score":0.09490153193473816},{"id":"https://openalex.org/keywords/biology","display_name":"Biology","score":0.08210739493370056}],"concepts":[{"id":"https://openalex.org/C139945424","wikidata":"https://www.wikidata.org/wiki/Q1940696","display_name":"Mean squared error","level":2,"score":0.5960111618041992},{"id":"https://openalex.org/C165838908","wikidata":"https://www.wikidata.org/wiki/Q736777","display_name":"Calibration","level":2,"score":0.5773704051971436},{"id":"https://openalex.org/C51417038","wikidata":"https://www.wikidata.org/wiki/Q272737","display_name":"Phenology","level":2,"score":0.490792840719223},{"id":"https://openalex.org/C105795698","wikidata":"https://www.wikidata.org/wiki/Q12483","display_name":"Statistics","level":1,"score":0.451842337846756},{"id":"https://openalex.org/C537208039","wikidata":"https://www.wikidata.org/wiki/Q627","display_name":"Nitrogen","level":2,"score":0.41676488518714905},{"id":"https://openalex.org/C39432304","wikidata":"https://www.wikidata.org/wiki/Q188847","display_name":"Environmental science","level":0,"score":0.407698392868042},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.39386919140815735},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.37833505868911743},{"id":"https://openalex.org/C62649853","wikidata":"https://www.wikidata.org/wiki/Q199687","display_name":"Remote sensing","level":1,"score":0.3593628406524658},{"id":"https://openalex.org/C6557445","wikidata":"https://www.wikidata.org/wiki/Q173113","display_name":"Agronomy","level":1,"score":0.14100536704063416},{"id":"https://openalex.org/C185592680","wikidata":"https://www.wikidata.org/wiki/Q2329","display_name":"Chemistry","level":0,"score":0.09490153193473816},{"id":"https://openalex.org/C86803240","wikidata":"https://www.wikidata.org/wiki/Q420","display_name":"Biology","level":0,"score":0.08210739493370056},{"id":"https://openalex.org/C127313418","wikidata":"https://www.wikidata.org/wiki/Q1069","display_name":"Geology","level":0,"score":0.0},{"id":"https://openalex.org/C178790620","wikidata":"https://www.wikidata.org/wiki/Q11351","display_name":"Organic chemistry","level":1,"score":0.0}],"mesh":[],"locations_count":4,"locations":[{"id":"doi:10.3390/rs70404527","is_oa":true,"landing_page_url":"https://doi.org/10.3390/rs70404527","pdf_url":"https://www.mdpi.com/2072-4292/7/4/4527/pdf?version=1429088447","source":{"id":"https://openalex.org/S43295729","display_name":"Remote Sensing","issn_l":"2072-4292","issn":["2072-4292"],"is_oa":true,"is_in_doaj":true,"is_core":true,"host_organization":"https://openalex.org/P4310310987","host_organization_name":"Multidisciplinary Digital Publishing Institute","host_organization_lineage":["https://openalex.org/P4310310987"],"host_organization_lineage_names":["Multidisciplinary Digital Publishing Institute"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Remote Sensing","raw_type":"journal-article"},{"id":"pmh:oai:doaj.org/article:8717263bd32348a39cea6200c4f2150d","is_oa":true,"landing_page_url":"https://doaj.org/article/8717263bd32348a39cea6200c4f2150d","pdf_url":null,"source":{"id":"https://openalex.org/S4306401280","display_name":"DOAJ (DOAJ: Directory of Open Access Journals)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":null,"host_organization_name":null,"host_organization_lineage":[],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by-sa","license_id":"https://openalex.org/licenses/cc-by-sa","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"Remote Sensing, Vol 7, Iss 4, Pp 4527-4548 (2015)","raw_type":"article"},{"id":"pmh:oai:ir.igsnrr.ac.cn:311030/38561","is_oa":true,"landing_page_url":"http://ir.igsnrr.ac.cn/handle/311030/38561","pdf_url":null,"source":null,"license":"cc-by-nc-sa","license_id":"https://openalex.org/licenses/cc-by-nc-sa","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"SCI/SSCI\u8bba\u6587"},{"id":"pmh:oai:mdpi.com:/2072-4292/7/4/4527/","is_oa":true,"landing_page_url":"https://dx.doi.org/10.3390/rs70404527","pdf_url":null,"source":{"id":"https://openalex.org/S4306400947","display_name":"MDPI (MDPI AG)","issn_l":null,"issn":null,"is_oa":true,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I4210097602","host_organization_name":"Multidisciplinary Digital Publishing Institute (Switzerland)","host_organization_lineage":["https://openalex.org/I4210097602"],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"Remote Sensing; Volume 7; Issue 4; Pages: 4527-4548","raw_type":"Text"}],"best_oa_location":{"id":"doi:10.3390/rs70404527","is_oa":true,"landing_page_url":"https://doi.org/10.3390/rs70404527","pdf_url":"https://www.mdpi.com/2072-4292/7/4/4527/pdf?version=1429088447","source":{"id":"https://openalex.org/S43295729","display_name":"Remote Sensing","issn_l":"2072-4292","issn":["2072-4292"],"is_oa":true,"is_in_doaj":true,"is_core":true,"host_organization":"https://openalex.org/P4310310987","host_organization_name":"Multidisciplinary Digital Publishing Institute","host_organization_lineage":["https://openalex.org/P4310310987"],"host_organization_lineage_names":["Multidisciplinary Digital Publishing Institute"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Remote Sensing","raw_type":"journal-article"},"sustainable_development_goals":[{"score":0.7599999904632568,"id":"https://metadata.un.org/sdg/2","display_name":"Zero hunger"}],"awards":[{"id":"https://openalex.org/G898021387","display_name":null,"funder_award_id":"41301378","funder_id":"https://openalex.org/F4320321001","funder_display_name":"National Natural Science Foundation of China"}],"funders":[{"id":"https://openalex.org/F4320321001","display_name":"National Natural Science Foundation of China","ror":"https://ror.org/01h0zpd94"}],"has_content":{"pdf":true,"grobid_xml":true},"content_urls":{"pdf":"https://content.openalex.org/works/W1982378832.pdf","grobid_xml":"https://content.openalex.org/works/W1982378832.grobid-xml"},"referenced_works_count":57,"referenced_works":["https://openalex.org/W106931194","https://openalex.org/W156992518","https://openalex.org/W221019484","https://openalex.org/W1906130215","https://openalex.org/W1973680308","https://openalex.org/W1974416151","https://openalex.org/W1984606650","https://openalex.org/W1992051154","https://openalex.org/W1996347147","https://openalex.org/W1998997260","https://openalex.org/W2000102737","https://openalex.org/W2000613913","https://openalex.org/W2001385123","https://openalex.org/W2012686349","https://openalex.org/W2013328968","https://openalex.org/W2013602923","https://openalex.org/W2019349143","https://openalex.org/W2034085189","https://openalex.org/W2035832455","https://openalex.org/W2035945221","https://openalex.org/W2043767409","https://openalex.org/W2044079993","https://openalex.org/W2046404820","https://openalex.org/W2056352756","https://openalex.org/W2061063014","https://openalex.org/W2062295773","https://openalex.org/W2062567499","https://openalex.org/W2065398692","https://openalex.org/W2076532457","https://openalex.org/W2083955053","https://openalex.org/W2084236720","https://openalex.org/W2089464686","https://openalex.org/W2093303536","https://openalex.org/W2095939249","https://openalex.org/W2103184761","https://openalex.org/W2105442343","https://openalex.org/W2109006150","https://openalex.org/W2111947859","https://openalex.org/W2118703810","https://openalex.org/W2119752000","https://openalex.org/W2127203138","https://openalex.org/W2128438912","https://openalex.org/W2135811725","https://openalex.org/W2135916781","https://openalex.org/W2145669224","https://openalex.org/W2146786221","https://openalex.org/W2161815745","https://openalex.org/W2163410149","https://openalex.org/W2167415195","https://openalex.org/W2167869331","https://openalex.org/W2318479078","https://openalex.org/W2338335839","https://openalex.org/W2364516510","https://openalex.org/W4388401211","https://openalex.org/W6658928019","https://openalex.org/W6665421014","https://openalex.org/W6673721019"],"related_works":["https://openalex.org/W2373524250","https://openalex.org/W4206027277","https://openalex.org/W2388003193","https://openalex.org/W2367450255","https://openalex.org/W2243549226","https://openalex.org/W2184048517","https://openalex.org/W3128824461","https://openalex.org/W2156132268","https://openalex.org/W96071508","https://openalex.org/W2388278526"],"abstract_inverted_index":{"Remote":[0],"predictions":[1],"of":[2,64,107,133,144,210,224,236],"the":[3,16,26,62,70,88,128,131,134,142,147,155,215,225,234,242,253],"nitrogen":[4,12],"nutrition":[5],"index":[6],"(NNI)":[7],"are":[8,29],"useful":[9],"for":[10,24,68,79,239,251,265],"precise":[11,266],"(N)":[13],"management":[14,259],"in":[15,36,102],"field.":[17],"Several":[18],"studies":[19,41],"have":[20,42],"recommended":[21,246],"two":[22,51,66,135],"methods":[23,35,67,138,148],"estimating":[25,69,252],"NNI,":[27],"which":[28,74],"classified":[30],"as":[31,56,247],"mechanistic":[32,156,243],"and":[33,48,94,111,116,141,184,194,196,201],"semi-empirical":[34,216],"this":[37,59,208,229],"study.":[38],"However,":[39,214],"no":[40,205],"been":[43],"conducted":[44,85],"to":[45,72,86],"thoroughly":[46],"analyze":[47],"compare":[49],"these":[50,65],"methods.":[52],"Using":[53],"winter":[54],"wheat":[55,99],"an":[57],"example,":[58],"study":[60],"compared":[61],"performances":[63,132,223],"NNI":[71,136,211],"determine":[73,87],"method":[75,157,217,230,244,250],"is":[76,245],"more":[77],"suitable":[78],"practical":[80],"use.":[81],"Field":[82],"measurements":[83],"were":[84,109,139,149,231],"above":[89,129],"ground":[90],"biomass,":[91],"N":[92,258,267],"concentration":[93],"canopy":[95],"spectra":[96],"during":[97],"different":[98,114,159],"growth":[100,171],"stages":[101],"2012.":[103],"Nearly":[104],"120":[105],"samples":[106],"data":[108,120,237],"collected":[110],"divided":[112],"into":[113],"calibration":[115,160],"validation":[117,167,177],"datasets":[118,161,168],"(containing":[119],"from":[121],"single":[122,170],"or":[123,172],"multi-growth":[124,173],"stages).":[125],"Based":[126],"on":[127,146,207],"datasets,":[130],"estimation":[137,212],"compared,":[140],"influences":[143],"phenology":[145],"analyzed.":[150],"All":[151],"models":[152,226],"that":[153],"used":[154,238,264],"with":[158],"performed":[162],"well":[163],"when":[164],"validated":[165],"by":[166,220,233],"containing":[169],"stage":[174],"data.":[175],"The":[176,222],"results":[178],"had":[179,204],"R2":[180],"values":[181,191,198],"between":[182,192,199],"0.82":[183],"0.94,":[185],"root":[186],"mean":[187],"square":[188],"error":[189],"(RMSE)":[190],"0.05":[193],"0.17,":[195],"RMSE%":[197],"5.10%":[200],"14.41%.":[202],"Phenology":[203],"effect":[206],"type":[209,235],"method.":[213],"was":[218],"influenced":[219],"phenology.":[221],"established":[227],"using":[228],"determined":[232],"calibration.":[240],"Thus,":[241],"a":[248],"better":[249],"NNI.":[254],"By":[255],"combining":[256],"proper":[257],"strategies,":[260],"it":[261],"can":[262],"be":[263],"management.":[268]},"counts_by_year":[{"year":2026,"cited_by_count":1},{"year":2025,"cited_by_count":10},{"year":2024,"cited_by_count":5},{"year":2023,"cited_by_count":4},{"year":2022,"cited_by_count":9},{"year":2021,"cited_by_count":8},{"year":2020,"cited_by_count":7},{"year":2019,"cited_by_count":9},{"year":2018,"cited_by_count":8},{"year":2017,"cited_by_count":1},{"year":2016,"cited_by_count":2}],"updated_date":"2026-07-22T07:51:19.307946","created_date":"2025-10-10T00:00:00"}
