After John wrote the abstract "对低碳热轧卷表面夹杂缺陷形貌、分布规律及相应成分进行分析.结果表明,结晶器保护渣卷入是引起低碳热轧卷表面夹杂缺陷的主要根源.在研究结晶器卷渣机理的基础上,通过调整保护渣成分,提高保护渣的黏度,并调整浸入式水口结构,优化结晶器流场,同时改进相关的工艺条件,使该类缺陷的发生率得到有效控制,由此引起的改判率也由4％降至0.2％以下,总体效果显著.", he wrote these keywords "表面夹杂, 卷渣, 黏度". Do you think his choice of keywords was correct? Answer yes or no.
yes