daylight changing meaning in Chinese

亮室换片
日光变化

But those were not enough - cause there are many factors that affect daylight , we cannot grasped the rule of daylight change . so most countries in the world , made the outdoor horizontal illuminance of overcast sky as the daylighting standard
为解决这些问题，各国的学者通过对本国光气候的长期观测得到了晴天天空、阴天天空和中间天空的天空亮度分布，并希望以此为依据，制定各个不同国家和地区的采光标准和天然采光的计算方法。