Question: Is the publication date not in 1981 for the industry whose operating system is Unix-like operating system?
Choices:
yes
no
unknown
unknown
unknown
unknown
unknown
unknown
unknown
unknown
Program:
function: Find
inputs: Unix-like operating system
function: Relate
dependencies: 0
inputs: operating system
backward
function: FilterConcept
dependencies: 1
inputs: industry
function: QueryAttr
dependencies: 2
inputs: publication date
function: VerifyYear
dependencies: 3
inputs: 1981
!=
SPARQL: ASK { ?e <pred:instance_of> ?c . ?c <pred:name> "industry" . ?e <operating_system> ?e_1 . ?e_1 <pred:name> "Unix-like operating system" .  ?e <publication_date> ?pv . ?pv <pred:year> ?v . FILTER ( ?v != 1981 ) .  }
Answer: yes