The XPS board was produced by Harbin Xin Hai Trading Co., Ltd. Its thickness is 10cm in the NSTIL, which was decided by the relevant research results [28]
此句中，Its thickness is 10cm in the NSTIL中的is，和which was decided by中的was是不冲突？是否要将is改成was才适合？
The XPS board was produced by Harbin Xin Hai Trading Co., Ltd. Its thickness is 10cm in the NSTIL, which was decided by the relevant research results.
【翻译】XPS板（一种板材名字，由木材或者钢材制作的）由哈尔滨鑫海贸易公司生产的。其厚度在NSTIL中为10厘米，这是由有关研究结果确定的。
was produced ：被动语态。指这种板材在过去生产的。
is 10cm ：指目前的尺寸。
was decided ：被动语态。“确定”这个动作在过去发生。
总体看，这个句子出现了两种时态。被动语态用过去时，指发生在过去的动作，一般目前时指客观存在的尺寸，不受时态限制。其实，is 10cm 改为 was10cm，也可以。都根据过去时间范畴理解即可。
