The authors have made a mistake in description of Eq. (2) in ISIJ Int., 59 (2019), No. 3, pp. 398–403. The authors are extremely regretful for the carelessness, and we would like to correct the equation as follows: (Formula Presented). The same mistake was made in Eq. (4) in ISIJ Int., 57 (2017), No. 12, pp. 2097–2106 as well. (Formula Presented). However, the authors have confirmed that calculation was made correctly, and thus there are no changes in the calculated results in each case. The authors apologize for any inconvenience caused by this mistake.
ASJC Scopus subject areas