System and method for providing semantic captchas for online advertisingVanja Josifovski,David M Pennock, Shanmugasundaram Ravikumar,Benjamin Clay Reed,Andrew Tomkinsmag(2008)引用 53|浏览40暂无评分AI 理解论文溯源树样例生成溯源树,研究论文发展脉络Chat Paper正在生成论文摘要