timedata <- c("2007-04-14 17:41:00 CST","2007-11-18 12:47:00 CST","2007-04-14 15:41:00 CST")

# 轉成POSIXct格式
timedata <- as.POSIXct(timedata, format="%Y-%m-%d %H:%M:%S")

write.csv(timedata, "test1.csv")
write.xlsx2(timedata, "test2.xlsx")