{"id":"https://openalex.org/W2295513779","doi":"https://doi.org/10.1109/isspa.2007.4555329","title":"Collage CAPTCHA","display_name":"Collage CAPTCHA","publication_year":2007,"publication_date":"2007-02-01","ids":{"openalex":"https://openalex.org/W2295513779","doi":"https://doi.org/10.1109/isspa.2007.4555329","mag":"2295513779"},"language":"en","primary_location":{"id":"doi:10.1109/isspa.2007.4555329","is_oa":false,"landing_page_url":"https://doi.org/10.1109/isspa.2007.4555329","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"2007 9th International Symposium on Signal Processing and Its Applications","raw_type":"proceedings-article"},"type":"conference-paper","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/A5109581803","display_name":"Mohammad Shirali-Shahreza","orcid":null},"institutions":[{"id":"https://openalex.org/I133529467","display_name":"Sharif University of Technology","ror":"https://ror.org/024c2fq17","country_code":"IR","type":"education","lineage":["https://openalex.org/I133529467"]}],"countries":["IR"],"is_corresponding":false,"raw_author_name":"Mohammad Shirali-Shahreza","raw_affiliation_strings":["Computer Science Department, Sharif University of Technology, Iran"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Computer Science Department, Sharif University of Technology, Iran","institution_ids":["https://openalex.org/I133529467"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5008842049","display_name":"Sajad Shirali-Shahreza","orcid":"https://orcid.org/0000-0001-5946-3243"},"institutions":[{"id":"https://openalex.org/I133529467","display_name":"Sharif University of Technology","ror":"https://ror.org/024c2fq17","country_code":"IR","type":"education","lineage":["https://openalex.org/I133529467"]}],"countries":["IR"],"is_corresponding":false,"raw_author_name":"Sajad Shirali-Shahreza","raw_affiliation_strings":["Computer Engineering Department, Sharif University of Technology, Iran"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Computer Engineering Department, Sharif University of Technology, Iran","institution_ids":["https://openalex.org/I133529467"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":1,"corresponding_author_ids":[],"corresponding_institution_ids":["https://openalex.org/I133529467"],"apc_list":null,"apc_paid":null,"fwci":5.0173,"has_fulltext":false,"cited_by_count":48,"citation_normalized_percentile":{"value":0.96494482,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":89,"max":97},"biblio":{"volume":null,"issue":null,"first_page":"1","last_page":"4"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11800","display_name":"User Authentication and Security Systems","score":1.0,"subfield":{"id":"https://openalex.org/subfields/1710","display_name":"Information Systems"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T11800","display_name":"User Authentication and Security Systems","score":1.0,"subfield":{"id":"https://openalex.org/subfields/1710","display_name":"Information Systems"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10828","display_name":"Biometric Identification and Security","score":0.991100013256073,"subfield":{"id":"https://openalex.org/subfields/1711","display_name":"Signal Processing"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10388","display_name":"Advanced Steganography and Watermarking Techniques","score":0.984000027179718,"subfield":{"id":"https://openalex.org/subfields/1707","display_name":"Computer Vision and Pattern Recognition"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/captcha","display_name":"CAPTCHA","score":0.9313386678695679},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.8447097539901733},{"id":"https://openalex.org/keywords/hacker","display_name":"Hacker","score":0.7126055359840393},{"id":"https://openalex.org/keywords/object","display_name":"Object (grammar)","score":0.5964239835739136},{"id":"https://openalex.org/keywords/turing-test","display_name":"Turing test","score":0.5918951034545898},{"id":"https://openalex.org/keywords/the-internet","display_name":"The Internet","score":0.5397947430610657},{"id":"https://openalex.org/keywords/simplicity","display_name":"Simplicity","score":0.5214033126831055},{"id":"https://openalex.org/keywords/software","display_name":"Software","score":0.49389487504959106},{"id":"https://openalex.org/keywords/ask-price","display_name":"Ask price","score":0.45664945244789124},{"id":"https://openalex.org/keywords/human\u2013computer-interaction","display_name":"Human\u2013computer interaction","score":0.42519378662109375},{"id":"https://openalex.org/keywords/world-wide-web","display_name":"World Wide Web","score":0.4077741503715515},{"id":"https://openalex.org/keywords/multimedia","display_name":"Multimedia","score":0.36829185485839844},{"id":"https://openalex.org/keywords/artificial-intelligence","display_name":"Artificial intelligence","score":0.3027037978172302},{"id":"https://openalex.org/keywords/computer-security","display_name":"Computer security","score":0.22049090266227722},{"id":"https://openalex.org/keywords/programming-language","display_name":"Programming language","score":0.19965949654579163}],"concepts":[{"id":"https://openalex.org/C163339463","wikidata":"https://www.wikidata.org/wiki/Q484598","display_name":"CAPTCHA","level":2,"score":0.9313386678695679},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.8447097539901733},{"id":"https://openalex.org/C86844869","wikidata":"https://www.wikidata.org/wiki/Q2798820","display_name":"Hacker","level":2,"score":0.7126055359840393},{"id":"https://openalex.org/C2781238097","wikidata":"https://www.wikidata.org/wiki/Q175026","display_name":"Object (grammar)","level":2,"score":0.5964239835739136},{"id":"https://openalex.org/C577917","wikidata":"https://www.wikidata.org/wiki/Q189223","display_name":"Turing test","level":2,"score":0.5918951034545898},{"id":"https://openalex.org/C110875604","wikidata":"https://www.wikidata.org/wiki/Q75","display_name":"The Internet","level":2,"score":0.5397947430610657},{"id":"https://openalex.org/C2776372474","wikidata":"https://www.wikidata.org/wiki/Q508291","display_name":"Simplicity","level":2,"score":0.5214033126831055},{"id":"https://openalex.org/C2777904410","wikidata":"https://www.wikidata.org/wiki/Q7397","display_name":"Software","level":2,"score":0.49389487504959106},{"id":"https://openalex.org/C90329073","wikidata":"https://www.wikidata.org/wiki/Q914232","display_name":"Ask price","level":2,"score":0.45664945244789124},{"id":"https://openalex.org/C107457646","wikidata":"https://www.wikidata.org/wiki/Q207434","display_name":"Human\u2013computer interaction","level":1,"score":0.42519378662109375},{"id":"https://openalex.org/C136764020","wikidata":"https://www.wikidata.org/wiki/Q466","display_name":"World Wide Web","level":1,"score":0.4077741503715515},{"id":"https://openalex.org/C49774154","wikidata":"https://www.wikidata.org/wiki/Q131765","display_name":"Multimedia","level":1,"score":0.36829185485839844},{"id":"https://openalex.org/C154945302","wikidata":"https://www.wikidata.org/wiki/Q11660","display_name":"Artificial intelligence","level":1,"score":0.3027037978172302},{"id":"https://openalex.org/C38652104","wikidata":"https://www.wikidata.org/wiki/Q3510521","display_name":"Computer security","level":1,"score":0.22049090266227722},{"id":"https://openalex.org/C199360897","wikidata":"https://www.wikidata.org/wiki/Q9143","display_name":"Programming language","level":1,"score":0.19965949654579163},{"id":"https://openalex.org/C111472728","wikidata":"https://www.wikidata.org/wiki/Q9471","display_name":"Epistemology","level":1,"score":0.0},{"id":"https://openalex.org/C162324750","wikidata":"https://www.wikidata.org/wiki/Q8134","display_name":"Economics","level":0,"score":0.0},{"id":"https://openalex.org/C136264566","wikidata":"https://www.wikidata.org/wiki/Q159810","display_name":"Economy","level":1,"score":0.0},{"id":"https://openalex.org/C138885662","wikidata":"https://www.wikidata.org/wiki/Q5891","display_name":"Philosophy","level":0,"score":0.0}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1109/isspa.2007.4555329","is_oa":false,"landing_page_url":"https://doi.org/10.1109/isspa.2007.4555329","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"2007 9th International Symposium on Signal Processing and Its Applications","raw_type":"proceedings-article"}],"best_oa_location":null,"sustainable_development_goals":[{"display_name":"Quality Education","id":"https://metadata.un.org/sdg/4","score":0.7900000214576721}],"awards":[],"funders":[],"has_content":{"grobid_xml":false,"pdf":false},"content_urls":null,"referenced_works_count":11,"referenced_works":["https://openalex.org/W1583950051","https://openalex.org/W1974008446","https://openalex.org/W2061777480","https://openalex.org/W2099256741","https://openalex.org/W2107612984","https://openalex.org/W2129824148","https://openalex.org/W2155915840","https://openalex.org/W2293311870","https://openalex.org/W4243164856","https://openalex.org/W4244463960","https://openalex.org/W6634830086"],"related_works":["https://openalex.org/W4312500010","https://openalex.org/W2313567600","https://openalex.org/W2086464669","https://openalex.org/W2965099444","https://openalex.org/W1999034556","https://openalex.org/W1998496804","https://openalex.org/W1991242267","https://openalex.org/W2910114670","https://openalex.org/W3144744384","https://openalex.org/W3015118614"],"abstract_inverted_index":{"Nowadays,":[0],"many":[1],"daily":[2],"human":[3,58,77,100,113,181],"activities":[4],"such":[5,19,144],"as":[6,20,66,145],"education,":[7],"commerce,":[8],"talks,":[9],"etc.":[10],"are":[11,81,97,136,150],"carried":[12],"out":[13],"through":[14],"the":[15,21,36,39,46,85,112,120,129,153,158,166,169,176,196,210],"Internet.":[16],"In":[17,102,131],"cases":[18],"registering":[22],"in":[23],"websites,":[24],"some":[25,134,142],"hackers":[26],"write":[27],"programs":[28,62],"to":[29,55,73,99,160,201],"make":[30],"automatic":[31],"false":[32],"enrolments":[33],"which":[34,63],"waste":[35],"resources":[37],"of":[38,88,122,124,148,189],"website":[40,48],"while":[41,94],"this":[42,103,132,190],"may":[43],"even":[44],"stop":[45],"entire":[47],"from":[49,60],"working.":[50],"Therefore,":[51],"it":[52],"is":[53,64,192],"necessary":[54],"tell":[56,74],"apart":[57,118],"users":[59,114],"computer":[61,116,184],"known":[65],"CAPTCHA":[67,79],"(completely":[68],"automated":[69],"p[ublic":[70],"turing":[71],"test":[72],"computers":[75],"and":[76,115,139],"apart).":[78],"methods":[80],"mainly":[82],"based":[83],"on":[84,119,128,152],"weak":[86],"points":[87],"OCR":[89],"(optical":[90],"character":[91],"recognition)":[92],"systems":[93],"using":[95],"them":[96,149],"undesirable":[98],"users.":[101],"paper":[104],"a":[105,162,180],"method":[106,133,191,205],"has":[107,178,206],"been":[108,179,207],"presented":[109],"for":[110],"telling":[111],"softwares":[117],"basis":[121],"choice":[123],"an":[125],"object":[126,171],"shown":[127,151],"screen.":[130,154],"pictures":[135],"chosen":[137],"randomly":[138],"after":[140],"effecting":[141],"changes":[143],"rotating,":[146],"all":[147],"Then":[155],"we":[156,172],"ask":[157],"user":[159,167,177,197],"choose":[161],"specific":[163],"object.":[164],"If":[165],"chooses":[168],"right":[170],"can":[173],"guess":[174],"that":[175],"being":[182],"not":[183,199],"software.":[185],"The":[186],"main":[187],"advantage":[188],"its":[193],"simplicity":[194],"because":[195],"does":[198],"have":[200],"type":[202],"anything.":[203],"This":[204],"implemented":[208],"by":[209],"Java":[211],"programming":[212],"language.":[213]},"counts_by_year":[{"year":2024,"cited_by_count":1},{"year":2022,"cited_by_count":1},{"year":2021,"cited_by_count":1},{"year":2020,"cited_by_count":3},{"year":2019,"cited_by_count":1},{"year":2017,"cited_by_count":3},{"year":2016,"cited_by_count":2},{"year":2015,"cited_by_count":1},{"year":2014,"cited_by_count":2},{"year":2013,"cited_by_count":3},{"year":2012,"cited_by_count":3}],"updated_date":"2026-07-29T14:22:42.915294","created_date":"2016-06-24T00:00:00"}
