In 2021 in Sensors, what are the titles of the papers on Transportation classification?
What are the titles of the papers on Transportation classification that were published in Sensors in 2021?
SELECT DISTINCT ?answer WHERE { <https://dblp.org/rec/journals/sensors/FriedrichLH21> <https://dblp.org/rdf/schema#publishedIn> 'Sensors' . <https://dblp.org/rec/journals/sensors/FriedrichLH21> <https://dblp.org/rdf/schema#yearOfPublication> '2021' . <https://dblp.org/rec/journals/sensors/FriedrichLH21> <https://dblp.org/rdf/schema#title> ?answer }
<https://dblp.org/rec/journals/sensors/FriedrichLH21>