狠狠撸

spatial crowdsourcing mobile crowdsourcing crowdsourcing location privacy gis video mobile crowdsensing spatial matching framework geo-tagged spatial differential privacy privacy disaster response image cloud mobile video upload video benchmark data collection mediaq analysis metadata first usc infolab multimedia communication social media ubiquitious mobile spatial task assignment cloud computing spatial crowdsensing cloaking query optimization histogram cardinality estimation entropy entropy-based histograms estimation error selectivity estimation vgi task matching volunteer geographic information expertise matching crowdsensing complex task task assignment